Assessing the Association between Thermotolerant Coliforms in Drinking Water and Diarrhea: An Analysis of Individual-Level Data from Multiple Studies.

PubMed

Hodge, James; Chang, Howard H; Boisson, Sophie; Collin, Simon M; Peletz, Rachel; Clasen, Thomas

2016-10-01

Fecally contaminated drinking water is believed to be a major contributor to the global burden of diarrheal disease and a leading cause of mortality among young children. However, recent systematic reviews and results from blinded studies of water quality interventions have raised questions about the risk associated with fecally contaminated water, particularly as measured by thermotolerant coliform (TTC) bacteria, a WHO-approved indicator of drinking water quality. We investigated the association between TTC in drinking water and diarrhea using data from seven previous studies. We obtained individual-level data from available field studies that measured TTC levels in household-drinking water and reported prevalence of diarrhea among household members during the days prior to the visit. The combined data set included diarrhea prevalence for 26,518 individuals and 8,000 water samples from 4,017 households, yielding 45,052 observations. The odds of diarrhea increased for each log10 increase in TTC/100 mL by 18% (95% CI: 11, 26%) for children < 5 years old and 12% (95% CI: 8, 18%) for all ages. For all ages, the odds of diarrhea increased by 21%, 35% and 49% for those whose household water samples were from 11-100, 101-1,000, and > 1,000 TTC/100 mL, respectively compared to < 1 TTC/100 mL. We found no evidence of increased odds of diarrhea with contamination levels below 11 TTC/100 mL, either in adults or children. Our analysis of individual-level data shows increased risk of diarrhea with increasing levels of TTC in drinking water. These results suggest an association between fecally contaminated water and diarrheal disease and provides support for health-based targets for levels of TTC in drinking water and for interventions to improve drinking water quality to prevent diarrhea. Hodge J, Chang HH, Boisson S, Collin SM, Peletz R, Clasen T. 2016. Assessing the association between thermotolerant coliforms in drinking water and diarrhea: an analysis of individual level data from multiple studies. Environ Health Perspect 124:1560-1567; http://dx.doi.org/10.1289/EHP156.

Assessing the Association between Thermotolerant Coliforms in Drinking Water and Diarrhea: An Analysis of Individual–Level Data from Multiple Studies

PubMed Central

Hodge, James; Chang, Howard H.; Boisson, Sophie; Collin, Simon M.; Peletz, Rachel; Clasen, Thomas

2016-01-01

Background: Fecally contaminated drinking water is believed to be a major contributor to the global burden of diarrheal disease and a leading cause of mortality among young children. However, recent systematic reviews and results from blinded studies of water quality interventions have raised questions about the risk associated with fecally contaminated water, particularly as measured by thermotolerant coliform (TTC) bacteria, a WHO-approved indicator of drinking water quality. Objectives: We investigated the association between TTC in drinking water and diarrhea using data from seven previous studies. Methods: We obtained individual-level data from available field studies that measured TTC levels in household-drinking water and reported prevalence of diarrhea among household members during the days prior to the visit. Results: The combined data set included diarrhea prevalence for 26,518 individuals and 8,000 water samples from 4,017 households, yielding 45,052 observations. The odds of diarrhea increased for each log10 increase in TTC/100 mL by 18% (95% CI: 11, 26%) for children < 5 years old and 12% (95% CI: 8, 18%) for all ages. For all ages, the odds of diarrhea increased by 21%, 35% and 49% for those whose household water samples were from 11–100, 101–1,000, and > 1,000 TTC/100 mL, respectively compared to < 1 TTC/100 mL. We found no evidence of increased odds of diarrhea with contamination levels below 11 TTC/100 mL, either in adults or children. Conclusions: Our analysis of individual-level data shows increased risk of diarrhea with increasing levels of TTC in drinking water. These results suggest an association between fecally contaminated water and diarrheal disease and provides support for health-based targets for levels of TTC in drinking water and for interventions to improve drinking water quality to prevent diarrhea. Citation: Hodge J, Chang HH, Boisson S, Collin SM, Peletz R, Clasen T. 2016. Assessing the association between thermotolerant coliforms in drinking water and diarrhea: an analysis of individual level data from multiple studies. Environ Health Perspect 124:1560–1567; http://dx.doi.org/10.1289/EHP156 PMID:27164618

Effects of Withdrawals on Ground-Water Levels in Southern Maryland and the Adjacent Eastern Shore, 1980-2005

USGS Publications Warehouse

Soeder, Daniel J.; Raffensperger, Jeff P.; Nardi, Mark R.

2007-01-01

Ground water is the primary source of water supply in most areas of Maryland?s Atlantic Coastal Plain, including Southern Maryland. The counties in this area are experiencing some of the most rapid growth and development in the State, resulting in an increased demand for ground-water production. The cooperative, basic water-data program of the U.S. Geological Survey and the Maryland Geological Survey has collected long-term observations of ground-water levels in Southern Maryland and parts of the Eastern Shore for many decades. Additional water-level observations were made by both agencies beginning in the 1970s, under the Power Plant Research Program of the Maryland Department of Natural Resources. These long-term water levels commonly show significant declines over several decades, which are attributed to ground-water withdrawals. Ground-water-level trends since 1980 in major Coastal Plain aquifers such as the Piney Point-Nanjemoy, Aquia, Magothy, upper Patapsco, lower Patapsco, and Patuxent were compared to water use and withdrawal data. Potentiometric surface maps show that most of the declines in ground-water levels can be directly related to effects from major pumping centers. There is also evidence that deep drawdowns in some pumped aquifers may be causing declines in adjacent, unpumped aquifers. Water-level hydrographs of many wells in Southern Maryland show linear declines in levels year after year, instead of the gradual leveling-off that would be expected as the aquifers equilibrate with pumping. A continual increase in the volumes of water being withdrawn from the aquifers is one explanation for why they are not reaching equilibrium. Although reported ground-water production in Southern Maryland has increased somewhat over the past several decades, the reported increases are often not large enough to account for the observed water-level declines. Numerical modeling simulations indicate that a steady, annual increase in the number of small wells could account for the observed aquifer behavior. Such wells, being pumped at rates below the minimum legal reporting threshold of 10,000 gallons per day, might be the source of the additional withdrawals. More detailed water-use data, especially from domestic wells, central-pivot irrigation wells, and other small users not currently reporting withdrawals to the State, may help to determine the cause of the aquifer declines.

Ground-Water Availability in the Wailuku Area, Maui, Hawai'i

USGS Publications Warehouse

Gingerich, Stephen B.

2008-01-01

Most of the public water supply in Maui, Hawai'i, is from a freshwater lens in the Wailuku area of the island. Because of population growth, ground-water withdrawals from wells in this area increased from less than 10 Mgal/d during 1970 to about 23 Mgal/d during 2006. In response to increased withdrawals from the freshwater lens in the Wailuku area, water levels declined, the transition zone between freshwater and saltwater became shallower, and the chloride concentrations of water pumped from wells increased. These responses led to concern over the long-term sustainability of withdrawals from existing and proposed wells. A three-dimensional numerical ground-water flow and transport model was developed to simulate the effects of selected withdrawal and recharge scenarios on water levels, on the transition zone between freshwater and saltwater, and on surface-water/ground-water interactions. The model was constructed using time-varying recharge, withdrawals, and ocean levels. Hydraulic characteristics used to construct the model were initially based on published estimates but ultimately were varied to obtain better agreement between simulated and measured water levels and salinity profiles in the modeled area during the period 1926-2006. Scenarios included ground-water withdrawal at 2006 and 1996 rates and locations with average recharge (based on 2000-04 land use and 1926-2004 rainfall) and withdrawal at redistributed rates and locations with several different recharge scenarios. Simulation results indicate that continuing 1996 and 2006 withdrawal distributions into the future results in decreased water levels, a thinner freshwater lens, increased salinity from pumped wells, and higher salinity at several current withdrawal sites. A redistributed withdrawal condition in which ground-water withdrawal was redistributed to maximize withdrawal and minimize salinities in the withdrawn water was determined. The redistributed withdrawal simulates 27.1 Mgal/d of withdrawal from 14 wells or well fields in the Wailuku area. Simulation results from the five scenarios that include redistributed withdrawal conditions indicate the following for the Wailuku Aquifer Sector: (1) withdrawal during times of average recharge rates cause average water levels to decrease 2-3 ft and the transition zone to become more than 200 ft shallower after 150 years; (2) a 5-yr drought condition similar to the 1998-2002 drought results in additional salinity increases after 30 years (12.5 years of normal recharge after drought conditions) but only one well has salinity increases of concern; (3) additional recharge from restored streamflow significantly increases water levels, thickens the freshwater body, and decreases salinity at withdrawal sites in the Waihe'e and 'Iao Aquifer Systems; and (4) a complete removal of irrigation recharge decreases water levels and increases salinity in the central isthmus where irrigation is reduced, but recharge through restored streams still significantly increases water levels, thickens the freshwater body, and decreases salinity at withdrawal sites in the Waihe'e and 'Iao Aquifer Systems.

Determining the optimal fluoride concentration in drinking water for fluoride endemic regions in South India.

PubMed

Viswanathan, Gopalan; Jaswanth, A; Gopalakrishnan, S; Siva Ilango, S; Aditya, G

2009-10-01

Fluoride ion in drinking water is known for both beneficial and detrimental effects on health. The prevalence of fluorosis is mainly due to the intake of large quantities of fluoride through drinking water owing to more than 90% bioavailability. The objective of this study is to predict optimal fluoride level in drinking water for fluoride endemic regions by comprising the levels of fluoride and other water quality parameters in drinking water, prevalence of fluorosis, fluoride intake through water, food and beverages such as tea and coffee and also considering the progressive accumulation of fluoride in animal bones, by comparing with non fluoride endemic areas comprise of the same geological features with the aid of regression analysis. Result of this study shows that increase of fluoride level above 1.33 mg/l in drinking water increases the community fluorosis index (CFI) value more than 0.6, an optimum index value above which fluorosis is considered to be a public health problem. Regression plot between water fluoride and bone fluoride levels indicates that, every increase of 0.5mg/l unit of water fluoride level increases the bone fluoride level of 52 mg/kg unit within 2 to 3 years. Furthermore, the consumption of drinking water containing more than 0.65 mg/l of fluoride can raise the total fluoride intake per day more than 4 mg, which is the optimum fluoride dose level recommended for adults by the Agency for Toxic Substances and Disease Registry. From the result, the people in fluoride endemic areas in South India are advised to consume drinking water with fluoride level within the limit of 0.5 to 0.65 mg/l to avoid further fluorosis risk.

Oxygenated drinking water enhances immune activity in pigs and increases immune responses of pigs during Salmonella typhimurium infection.

PubMed

Jung, Bock-Gie; Lee, Jin-A; Lee, Bong-Joo

2012-12-01

It has been considered that drinking oxygenated water improves oxygen availability, which may increase vitality and improve immune functions. The present study evaluated the effects of oxygenated drinking water on immune function in pigs. Continuous drinking of oxygenated water markedly increased peripheral blood mononuclear cell proliferation, interleukin-1β expression level and the CD4(+):CD8(+) cell ratio in pigs. During Salmonella Typhimurium infection, total leukocytes and relative cytokines expression levels were significantly increased in pigs consuming oxygenated water compared with pigs consuming tap water. These findings suggest that oxygenated drinking water enhances immune activity in pigs and increases immune responses of pigs during S. Typhimurium Infection.

Aquatic treadmill water level influence on pelvic limb kinematics in cranial cruciate ligament-deficient dogs with surgically stabilised stifles.

PubMed

Bertocci, G; Smalley, C; Brown, N; Bialczak, K; Carroll, D

2018-02-01

To compare pelvic limb joint kinematics and temporal gait characteristics during land-based and aquatic-based treadmill walking in dogs that have undergone surgical stabilisation for cranial cruciate ligament deficiency. Client-owned dogs with surgically stabilised stifles following cranial cruciate ligament deficiency performed three walking trials consisting of three consecutive gait cycles on an aquatic treadmill under four water levels. Hip, stifle and hock range of motion; peak extension; and peak flexion were assessed for the affected limb at each water level. Gait cycle time and stance phase percentage were also determined. Ten client-owned dogs of varying breeds were evaluated at a mean of 55·2 days postoperatively. Aquatic treadmill water level influenced pelvic limb kinematics and temporal gait outcomes. Increased stifle joint flexion was observed as treadmill water level increased, peaking when the water level was at the hip. Similarly, hip flexion increased at the hip water level. Stifle range of motion was greatest at stifle and hip water levels. Stance phase percentage was significantly decreased when water level was at the hip. Aquatic treadmill walking has become a common rehabilitation modality following surgical stabilisation of cranial cruciate ligament deficiency. However, evidence-based best practice guidelines to enhance stifle kinematics do not exist. Our findings suggest that rehabilitation utilising a water level at or above the stifle will achieve the best stifle kinematics following surgical stifle stabilisation. © 2017 British Small Animal Veterinary Association.

Correlation between lead levels in drinking water and mothers' breast milk: Dakahlia, Egypt.

PubMed

Mandour, Raafat A; Ghanem, Abdel-Aziz; El-Azab, Somaia M

2013-04-01

This study was performed on fifty-two drinking tap water samples (surface and groundwater) collected from different districts of Dakahlia Governorate and fifty-two breast milk samples from lactating mothers hosted in Dakahlia Governorate hospitals. All these samples were subjected to lead analysis. Lead level in drinking groundwater showed higher levels than in drinking surface water. Also, an elevation of lead levels in breast milk of mothers drinking groundwater was noticed when compared with that of mothers drinking surface water. The comparison between mean lead levels in drinking water and mothers' breast milk samples showed positive relationship. Lead concentrations in breast milk of the studied samples were elevated by exposure to smoking. We conclude that prolonged contact with lead plumbing can increase the lead content in tap water with subsequent increase in lead burden in infant fed formula and infant blood. Also, we recommend that chemical analyses must be carried out periodically for the surface and groundwater to ensure the water suitability for drinking purposes. Passive exposure to smoking during lactation should be avoided. Capsule: Prolonged contact with lead plumbing can increase the lead content in tap water with subsequent increase in lead burden in infant fed formula and infant blood.

Modeling Caspian Sea water level oscillations under different scenarios of increasing atmospheric carbon dioxide concentrations.

PubMed

Roshan, Gholamreza; Moghbel, Masumeh; Grab, Stefan

2012-12-12

The rapid rise of Caspian Sea water level (about 2.25 meters since 1978) has caused much concern to all five surrounding countries, primarily because flooding has destroyed or damaged buildings and other engineering structures, roads, beaches and farm lands in the coastal zone. Given that climate, and more specifically climate change, is a primary factor influencing oscillations in Caspian Sea water levels, the effect of different climate change scenarios on future Caspian Sea levels was simulated. Variations in environmental parameters such as temperature, precipitation, evaporation, atmospheric carbon dioxide and water level oscillations of the Caspian sea and surrounding regions, are considered for both past (1951-2006) and future (2025-2100) time frames. The output of the UKHADGEM general circulation model and five alternative scenarios including A1CAI, BIASF, BIMES WRE450 and WRE750 were extracted using the MAGICC SCENGEN Model software (version 5.3). The results suggest that the mean temperature of the Caspian Sea region (Bandar-E-Anzali monitoring site) has increased by ca. 0.17°C per decade under the impacts of atmospheric carbon dioxide changes (r=0.21). The Caspian Sea water level has increased by ca. +36cm per decade (r=0.82) between the years 1951-2006. Mean results from all modeled scenarios indicate that the temperature will increase by ca. 3.64°C and precipitation will decrease by ca. 10% (182 mm) over the Caspian Sea, whilst in the Volga river basin, temperatures are projected to increase by ca. 4.78°C and precipitation increase by ca. 12% (58 mm) by the year 2100. Finally, statistical modeling of the Caspian Sea water levels project future water level increases of between 86 cm and 163 cm by the years 2075 and 2100, respectively.

Modeling Caspian Sea water level oscillations under different scenarios of increasing atmospheric carbon dioxide concentrations

PubMed Central

2012-01-01

The rapid rise of Caspian Sea water level (about 2.25 meters since 1978) has caused much concern to all five surrounding countries, primarily because flooding has destroyed or damaged buildings and other engineering structures, roads, beaches and farm lands in the coastal zone. Given that climate, and more specifically climate change, is a primary factor influencing oscillations in Caspian Sea water levels, the effect of different climate change scenarios on future Caspian Sea levels was simulated. Variations in environmental parameters such as temperature, precipitation, evaporation, atmospheric carbon dioxide and water level oscillations of the Caspian sea and surrounding regions, are considered for both past (1951-2006) and future (2025-2100) time frames. The output of the UKHADGEM general circulation model and five alternative scenarios including A1CAI, BIASF, BIMES WRE450 and WRE750 were extracted using the MAGICC SCENGEN Model software (version 5.3). The results suggest that the mean temperature of the Caspian Sea region (Bandar-E-Anzali monitoring site) has increased by ca. 0.17°C per decade under the impacts of atmospheric carbon dioxide changes (r=0.21). The Caspian Sea water level has increased by ca. +36cm per decade (r=0.82) between the years 1951-2006. Mean results from all modeled scenarios indicate that the temperature will increase by ca. 3.64°C and precipitation will decrease by ca. 10% (182 mm) over the Caspian Sea, whilst in the Volga river basin, temperatures are projected to increase by ca. 4.78°C and precipitation increase by ca. 12% (58 mm) by the year 2100. Finally, statistical modeling of the Caspian Sea water levels project future water level increases of between 86 cm and 163 cm by the years 2075 and 2100, respectively. PMID:23369617

Diffuse radiation increases global ecosystem-level water-use efficiency

NASA Astrophysics Data System (ADS)

Moffat, A. M.; Reichstein, M.; Cescatti, A.; Knohl, A.; Zaehle, S.

2012-12-01

Current environmental changes lead not only to rising atmospheric CO2 levels and air temperature but also to changes in air pollution and thus the light quality of the solar radiation reaching the land-surface. While rising CO2 levels are thought to enhance photosynthesis and closure of stomata, thus leading to relative water savings, the effect of diffuse radiation on transpiration by plants is less clear. It has been speculated that the stimulation of photosynthesis by increased levels of diffuse light may be counteracted by higher transpiration and consequently water depletion and drought stress. Ultimately, in water co-limited systems, the overall effect of diffuse radiation will depend on the sensitivity of canopy transpiration versus photosynthesis to diffuse light, i.e. whether water-use efficiency changes with relative levels of diffuse light. Our study shows that water-use efficiency increases significantly with higher fractions of diffuse light. It uses the ecosystem-atmosphere gas-exchange observations obtained with the eddy covariance method at 29 flux tower sites. In contrast to previous global studies, the analysis is based directly on measurements of diffuse radiation. Its effect on water-use efficiency was derived by analyzing the multivariate response of carbon and water fluxes to radiation and air humidity using a purely empirical approach based on artificial neural networks. We infer that per unit change of diffuse fraction the water-use efficiency increases up to 40% depending on diffuse fraction levels and ecosystem type. Hence, in regions with increasing diffuse radiation positive effects on primary production are expected even under conditions where water is co-limiting productivity.

Rate of antioxidant degradation and color variations in dehydrated apples as related to water activity.

PubMed

Lavelli, Vera; Vantaggi, Claudia

2009-06-10

Dehydrated apples were studied to evaluate the effects of water activity on the stability of their antioxidants and color. Apples were freeze-dried, ground, then equilibrated, and stored at eight water activity levels, ranging from 0.058 to 0.747, at 40 degrees C. Their contents of hydroxycinnamic acids, dihydrochalcones, catechin, epicatechin, polymeric flavan-3-ols, and hydroxymethylfurfural, their antioxidant activity values, and their Hunter colorimetric parameters were analyzed at different storage times. Antioxidant degradation followed pseudo-first-order kinetics and was accelerated by increasing the water activity. The order of antioxidant stability in the products at water activity levels below 0.316 was catechin, epicatechin, and ascorbic acid < total procyanidins < dihydrochalcones and p-coumaric acid < chlorogenic acid; however, in the products at water activity levels above 0.316, the degradation of all antioxidants was very fast. The hydroxymethylfurfural formation rate increased exponentially during storage, especially at high water activity levels. The antioxidant activity of the dehydrated apples decreased during storage, consistent with antioxidant loss. The variations of the colorimetric parameters, namely, lightness (L*), redness (a*), and yellowness (b*), followed pseudo-zero-order kinetics and were accelerated by increasing water activity. All analytical indices indicated that the dehydrated apples were stable at water activity levels below 0.316, with the degradation rate accelerating upon exposure to higher relative humidities. Above 0.316, a small increase in water activity of the product would sharply increase the degradation rate constants for both antioxidant and color variations.

Water levels shape fishing participation in flood-control reservoirs

USGS Publications Warehouse

Miranda, Leandro E.; Meals, K. O.

2013-01-01

We examined the relationship between fishing effort (hours fished) and average March–May water level in 3 flood control reservoirs in Mississippi. Fishing effort increased as water level rose, peaked at intermediate water levels, and decreased at high water levels. We suggest that the observed arched-shaped relationship is driven by the shifting influence of fishability (adequacy of the fishing circumstances from an angler's perspective) and catch rate along a water level continuum. Fishability reduces fishing effort during low water, despite the potential for higher catch rates. Conversely, reduced catch rates and fishability at high water also curtail effort. Thus, both high and low water levels seem to discourage fishing effort, whereas anglers seem to favor intermediate water levels. Our results have implications for water level management in reservoirs with large water level fluctuations.

Carboxyhaemoglobin levels in water-pipe and cigarette smokers.

PubMed

Theron, Ansa; Schultz, Cedric; Ker, James A; Falzone, Nadia

2010-01-29

Water-pipe smoking is growing in popularity, especially among young people, because of the social nature of the smoking session and the assumption that the effects are less harmful than those of cigarette smoking. It has however been shown that a single water-pipe smoking session produces a 24-hour urinary cotinine level equivalent to smoking 10 cigarettes per day. We aimed to measure carboxyhaemoglogin (COHb) blood levels before and after water-pipe and cigarette smoking sessions. Self-confessed smokers older than 18 years (N=30) volunteered to smoke a water-pipe or a cigarette and have their blood COHb levels measured under controlled conditions. Mean baseline COHb levels were 2.9% for the 15 cigarette smokers and 1.0% for the 15 water-pipe smokers. Levels increased by a mean of 481.7% in water-pipe smokers as opposed to 39.9% in cigarette smokers. The study demonstrated that water-pipe smokers had significantly higher increases in blood COHb levels than cigarette smokers during a single smoking session.

Analysis of ground-water data for selected wells near Holloman Air Force Base, New Mexico, 1950-95

USGS Publications Warehouse

Huff, G.F.

1996-01-01

Ground-water-level, ground-water-withdrawal, and ground- water-quality data were evaluated for trends. Holloman Air Force Base is located in the west-central part of Otero County, New Mexico. Ground-water-data analyses include assembly and inspection of U.S. Geological Survey and Holloman Air Force Base data, including ground-water-level data for public-supply and observation wells and withdrawal and water-quality data for public-supply wells in the area. Well Douglas 4 shows a statistically significant decreasing trend in water levels for 1972-86 and a statistically significant increasing trend in water levels for 1986-90. Water levels in wells San Andres 5 and San Andres 6 show statistically significant decreasing trends for 1972-93 and 1981-89, respectively. A mixture of statistically significant increasing trends, statistically significant decreasing trends, and lack of statistically significant trends over periods ranging from the early 1970's to the early 1990's are indicated for the Boles wells and wells near the Boles wells. Well Boles 5 shows a statistically significant increasing trend in water levels for 1981-90. Well Boles 5 and well 17S.09E.25.343 show no statistically significant trends in water levels for 1990-93 and 1988-93, respectively. For 1986-93, well Frenchy 1 shows a statistically significant decreasing trend in water levels. Ground-water withdrawal from the San Andres and Douglas wells regularly exceeded estimated ground-water recharge from San Andres Canyon for 1963-87. For 1951-57 and 1960-86, ground-water withdrawal from the Boles wells regularly exceeded total estimated ground-water recharge from Mule, Arrow, and Lead Canyons. Ground-water withdrawal from the San Andres and Douglas wells and from the Boles wells nearly equaled estimated ground- water recharge for 1989-93 and 1986-93, respectively. For 1987- 93, ground-water withdrawal from the Escondido well regularly exceeded estimated ground-water recharge from Escondido Canyon, and ground-water withdrawal from the Frenchy wells regularly exceeded total estimated ground-water recharge from Dog and Deadman Canyons. Water-quality samples were collected from selected Douglas, San Andres, and Boles public-supply wells from December 1994 to February 1995. Concentrations of dissolved nitrate show the most consistent increases between current and historical data. Current concentrations of dissolved nitrate are greater than historical concentrations in 7 of 10 wells.

Is consolidation drainage an indirect mechanism for increased abundance of cattail in northern prairie wetlands?

USGS Publications Warehouse

Wiltermuth, Mark T.; Anteau, Michael J.

2016-01-01

In the Prairie Pothole Region of North America, disturbances to wetlands that disrupt water-level fluctuations in response to wet–dry climatic conditions have the potential to alter natural vegetative communities in favor of species that proliferate in stable environments, such as cattail (Typha spp.). We evaluated the effect of water-level dynamics during a recent fluctuation in wet–dry conditions on cattail coverage within semipermanently and permanently ponded wetlands situated in watersheds with different land use and amounts of wetland drainage. We found that ponded water depth increase was significantly greater in wetlands where water levels were not near the spill point of the topographic basin, where banks were steeper, and in larger wetlands where past dry conditions had less influence on change in pond area. Proportion of the wetland covered by cattail was negatively correlated with increased water depth, bank slope and pond area. Our observations provide evidence that cattail coverage in prairie wetlands is regulated by water-level fluctuations and that land use surrounding the wetland might have an indirect effect on cattail coverage by altering water-level response to wet–dry climate conditions. For example, drainage of smaller wetlands into larger wetlands that are characterized by more permanent hydroperiods, leads to stabilized water levels near their spill point and is therefore a potential mechanism for increased cattail abundance in the northern prairie region.

Ground-water flow and quality in the Atlantic City 800-foot sand, New Jersey

USGS Publications Warehouse

McAuley, Steven D.; Barringer, Julia L.; Paulachok, Gary N.; Clark, Jeffrey S.; Zapecza, Otto S.

2001-01-01

The regional, confined Atlantic City 800-foot sand is the principal source of water supply for coastal communities of southern New Jersey. In response to extensive use of the aquifer--nearly 21 million gallons per day in 1986--water levels have declined to about 100 feet below sea level near Atlantic City and remain below sea level throughout the coastal areas of southern New Jersey, raising concerns about the potential for saltwater intrusion into well fields. Water levels in the Atlantic City 800-foot sand have declined in response to pumping from the aquifer since the 1890's. Water levels in the first wells drilled into the Atlantic City 800-foot sand were above land surface, and water flowed continuously from the wells. By 1986, water levels were below sea level throughout most of the coastal areas. Under current conditions, wells near the coast derive most of their supply from lateral flow contributed from the unconfined part of the aquifer northwest of the updip limit of the confining unit that overlies the Atlantic City 800- foot sand. Ground water also flows laterally from offshore areas and leaks vertically through the overlying and underlying confining units into the Atlantic City 800-foot sand. The decline in water levels upsets the historical equilibrium between freshwater and ancient saltwater in offshore parts of the aquifer and permits the lateral movement of saltwater toward pumping centers. The rate of movement is accelerated as the decline in water levels increases. The chloride concentration of aquifer water 5.3 miles offshore of Atlantic City was measured as 77 mg/L (milligrams per liter) in 1985 at a U.S. Geological Survey observation well. Salty water has also moved toward wells in Cape May County. The confined, regional nature of the Atlantic City 800-foot sand permits water levels in Cape May County to decline in response to pumping in Atlantic County and vice versa. Historically, chloride concentrations as great as 1 ,510 mg/L have been reported for water in a former supply well in southern Cape May County. These data indicate that salty water has moved inland in Cape May County. Analysis of the chloride-concentration data indicates that ground water with a chloride concentration of 250 mg/L is within 4 miles of supply wells in Stone Harbor, Cape May County, and is about 10 miles offshore of supply wells near Atlantic City. Results of numerical simulations of ground-water flow were analyzed to determine the effects of four water-supply alternatives on water levels, the flow budget, and potential saltwater movement toward pumping centers during 1986-2040. In the supply alternatives, pumpage is (1) held constant at 1986 rates of pumpage; (2) increased by 35 percent at 1986 locations; (3) increased by 35 percent, but with relocation of some supply wells further inland; and (4) increased by 35 percent but with some of the increase derived from inland wells tapping the Kirkwood-Cohansey aquifer system rather than the Atlantic City 800-foot sand. Inland relocation of supply wells closer to the updip limit of the overlying confining unit results in the smallest decline in water levels and the smallest rate of ground-water flow between the offshore location of salty water and coastal supply wells. Increased pumpage from coastal supply wells results in the greatest water-level declines and the greatest increase in the rate of ground-water flow from offshore to coastal wells. Flow of undesirable salty ground water from offshore locations remains nearly the same as for current (1986) conditions when pumping rates do not change, and the flow-rate increase is smallest for the relocated pumpage (fourth) alternative. In comparing the two conditions of a 35-percent increase in pumpage, the flow from undesirable salty water positions is lessened and flow from the unconfined aquifer is increased when some of the pumping centers are relocated farther inland. Ground water from the 250-mg/L isochlor position does not reach supply wells during any simulated conditions predicted for 1986-2040. The analysis of the simulation, however, includes only advective freshwater flow from an estimated 250-mg/L isochlor position and does not include density effects. A chloride concentration data-collection network could be designed to monitor for saltwater intrusion and serve as an early warning system for the communities of southern Cape May County and the coastal communities near Atlantic City. Data from existing offshore wells could continue to serve as an early warning system for the Atlantic City area; however, observation wells south of Stone Harbor, in the Wildwood area, would be useful as an early warning system for southern Cape May County.

Assessing water quality of the Chesapeake Bay by the impact of sea level rise and warming

NASA Astrophysics Data System (ADS)

Wang, P.; Linker, L.; Wang, H.; Bhatt, G.; Yactayo, G.; Hinson, K.; Tian, R.

2017-08-01

The influence of sea level rise and warming on circulation and water quality of the Chesapeake Bay under projected climate conditions in 2050 were estimated by computer simulation. Four estuarine circulation scenarios in the estuary were run using the same watershed load in 1991-2000 period. They are, 1) the Base Scenario, which represents the current climate condition, 2) a Sea Level Rise Scenario, 3) a Warming Scenario, and 4) a combined Sea Level Rise and Warming Scenario. With a 1.6-1.9°C increase in monthly air temperatures in the Warming Scenario, water temperature in the Bay is estimated to increase by 0.8-1°C. Summer average anoxic volume is estimated to increase 1.4 percent compared to the Base Scenario, because of an increase in algal blooms in the spring and summer, promotion of oxygen consumptive processes, and an increase of stratification. However, a 0.5-meter Sea Level Rise Scenario results in a 12 percent reduction of anoxic volume. This is mainly due to increased estuarine circulation that promotes oxygen-rich sea water intrusion in lower layers. The combined Sea Level Rise and Warming Scenario results in a 10.8 percent reduction of anoxic volume. Global warming increases precipitation and consequently increases nutrient loads from the watershed by approximately 5-7 percent. A scenario that used a 10 percent increase in watershed loads and current estuarine circulation patterns yielded a 19 percent increase in summer anoxic volume, while a scenario that used a 10 percent increase in watershed loads and modified estuarine circulation patterns by the aforementioned sea level rise and warming yielded a 6 percent increase in summer anoxic volume. Impacts on phytoplankton, sediments, and water clarity were also analysed.

Tidal-Fluvial and Estuarine Processes in the Lower Columbia River: I. Along-channel Water Level Variations, Pacific Ocean to Bonneville Dam

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jay, D. A.; Leffler, K.; Diefenderfer, Heida L.

This two-part paper provides comprehensive time and frequency domain analyses and models of along-channel water level variations in the 234km-long Lower Columbia River and Estuary (LCRE) and documents the response of floodplain wetlands thereto. In Part I, power spectra, continuous wavelet transforms, and harmonic analyses are used to understand the influences of tides, river flow, upwelling and downwelling, and hydropower operations ("power-peaking") on the water level regime. Estuarine water levels are influenced primarily by astronomical tides and coastal processes, and secondarily by river flow. The importance of coastal and tidal influences decreases in the landward direction, and water levels aremore » increasingly controlled by river flow variations at periods from ≤1 day to years. Water level records are only slightly non-stationary near the ocean, but become increasingly irregular upriver. Although astronomically forced tidal constituents decrease above the estuary, tidal fortnightly and overtide variations increase for 80-200km landward, both relative to major tidal constituents and in absolute terms.« less

Identifying the Source of High-Nitrate Ground Water Related to Artificial Recharge in a Desert Basin

NASA Astrophysics Data System (ADS)

Densmore, J. N.; Nishikawa, T.; Bohlke, J. K.; Martin, P.

2002-12-01

Ground water has been the sole source of water supply for the community of Yucca Valley in the Mojave Desert, California. Domestic wastewater from the community is treated using septic tanks. An imbalance between ground-water recharge and pumpage caused ground-water levels in the ground-water basin to decline by as much as 300 feet from the late 1940s through 1994. In response to this decline, the local water district, Hi-Desert Water District, began an artificial recharge program in February 1995 to replenish the ground water in the basin using imported surface water. The artificial recharge program resulted in water-level recovery of about 250 feet between February 1995 and December 2001; however, nitrate concentrations in some wells also increased from a background concentration of 10 mg/L as NO3 to more than the U.S. Environmental Protection Agency maximum contaminant level of 45 mg/L as NO3, limiting water use for some wells. The largest increase in nitrate concentrations occurred adjacent to the artificial recharge sites where the largest increase in water levels occurred even though the recharge water had low nitrate concentrations. The source of high nitrate concentrations observed in ground water during aquifer recovery was identified by compiling historical water-quality data; monitoring changes in water quality since artificial recharge began; and analyzing selected samples for major-ion chemistry, stable isotopes of H,O, and N, caffeine, and pharmaceuticals. The major-ions and H and O stable-isotope data indicate that ground-water samples that had the highest nitrate concentrations were mixtures of imported water and native ground water. Nitrate-to-chloride ratios, N isotopes and caffeine and pharmaceutical data indicate septic-tank seepage (septage) is the primary source of increases in nitrate concentration. The rapid rise in water levels entrained the large volume of high-nitrate septage stored in the unsaturated zone, resulting in the rapid increase in nitrate concentrations. Results of this study indicate that the potential for ground-water contamination should be evaluated before beginning an artificial recharge program in an area that uses septic tanks.

Analysis of water level variation of lakes and reservoirs in Xinjiang, China using ICESat laser altimetry data (2003–2009)

PubMed Central

Liu, Hongxing; Chen, Yaning; Shu, Song; Wu, Qiusheng; Wang, Shujie

2017-01-01

This study utilizes ICESat Release 33 GLA14 data to analyse water level variation of Xinjiang’s lakes and reservoirs from 2003 to 2009. By using Landsat images, lakes and reservoirs with area larger than 1 km2 are numerically delineated with a software tool. Based on ICESat observations, we analyse the characteristics of water level variation in different geographic environments, as well as investigate the reasons for the variation. Results indicate that climatic warming contributes to rising water levels in lakes in mountainous areas, especially for lakes that are recharged by snow and glacial melting. For lakes in oases, the water levels are affected jointly by human activity and climate change, while the water levels of reservoirs are mainly affected by human activity. Comparing the annual average rates of water levels, those of lakes are higher than those of reservoirs in oasis areas. The main reasons for the decreasing water levels in desert regions are the reduction of recharged runoff and high evaporation. By analysing the variation of water levels and water volume in different geologic environments, it is found that water level and volume increased in mountainous regions, and decreased in oasis regions and desert regions. Finding also demonstrate that decreasing volume is greater than increasing volume, which results in decreasing total volume of Xinjiang lakes and reservoirs. PMID:28873094

Simulation of the ground-water-flow system in the Kalamazoo County area, Michigan

USGS Publications Warehouse

Luukkonen, Carol L.; Blumer, Stephen P.; Weaver, T.L.; Jean, Julie

2004-01-01

A ground-water-flow model was developed to investigate the ground-water resources of Kalamazoo County. Ground water is widely used as a source of water for drinking and industry in Kalamazoo County and the surrounding area. Additionally, lakes and streams are valued for their recreational and aesthetic uses. Stresses on the ground-water system, both natural and human-induced, have raised concerns about the long-term availability of ground water for people to use and for replenishment of lakes and streams. Potential changes in these stresses, including withdrawals and recharge, were simulated using a ground-water-flow model. Simulations included steady-state conditions (in which stresses remained constant and changes in storage were not included) and transient conditions (in which stresses changed in seasonal and monthly time scales and storage within the system was included). Steady-state simulations were used to investigate the long-term effects on water levels and streamflow of a reduction in recharge or an increase in pumping to projected 2010 withdrawal rates, withdrawal and application of water for irrigation, and a reduction in recharge in urban areas caused by impervious surfaces. Transient simulations were used to investigate changes in withdrawals to match seasonal and monthly patterns under various recharge conditions, and the potential effects of the use of water for irrigation over the summer months. With a reduction in recharge, simulated water levels declined over most of the model area in Kalamazoo County; with an increase in pumping, water levels declined primarily near pumping centers. Because withdrawals by wells intercept water that would have discharged possibly to a stream or lake, model simulations indicated that streamflow was reduced with increased withdrawals. With withdrawal and consumption of water for irrigation, simulated water levels declined. Assuming a reduction in recharge due to urbanization, water levels declined and flow to streams was reduced based on steady-state simulation results. Transient results indicated a reduction of water levels with the simulated use of water for irrigation over the summer months. Generally the transient simulation with recharge only in the winter provided the best fit to observed water levels collected during synoptic water-level measurements in some wells and to the trends observed in water levels for other wells. Analysis of the regional hydrologic budgets provides an increased understanding of water movement within the ground-water-flow system in Kalamazoo County. Budgets for the steady-state simulations indicated that with reduced recharge, less water was available for streamflow and less water left the model area through the model boundaries. Similarly, with an increase in pumping rates, less water was available to enter streams and become streamflow. When recharge was assumed to remain constant and when it was allowed to vary throughout the year, the amount of water that entered storage was greater than that which left storage. However, when recharge was distributed through October?May only or when recharge rates were reduced from October to May, the amount of water that entered storage was less than that which left storage. Thus, on the basis of model simulations, with reduced recharge or increased withdrawals, water must come from storage, rivers, or from ground-flow-system boundaries to meet withdrawal demands.

Effect of Climate Change on Water Temperature and ...

EPA Pesticide Factsheets

There is increasing evidence that our planet is warming and this warming is also resulting in rising sea levels. Estuaries which are located at the interface between land and ocean are impacted by these changes. We used CE-QUAL-W2 water quality model to predict changes in water temperature as a function of increasing air temperatures and rising sea level for the Yaquina Estuary, Oregon (USA). Annual average air temperature in the Yaquina watershed is expected to increase about 0.3 deg C per decade by 2040-2069. An air temperature increase of 3 deg C in the Yaquina watershed is likely to result in estuarine water temperature increasing by 0.7 to 1.6 deg C. Largest water temperature increases are expected in the upper portion of the estuary, while sea level rise may ameliorate some of the warming in the lower portion of the estuary. Smallest changes in water temperature are predicted to occur in the summer, and maximum changes during the winter and spring. Increases in air temperature may result in an increase in the number of days per year that the 7-day maximum average temperature exceeds 18 deg C (criterion for protection of rearing and migration of salmonids and trout) as well as other water quality concerns. In the upstream portion of the estuary, a 4 deg C increase in air temperature is predicted to cause an increase of 40 days not meeting the temperature criterion, while in the lower estuary the increase will depend upon rate of sea level rise (rang

Status of Ground-Water Levels and Storage Volume in the Equus Beds Aquifer Near Wichita, Kansas, January 2003-January 2006

USGS Publications Warehouse

Hansen, Cristi V.

2007-01-01

The Equus Beds aquifer northwest of Wichita, Kansas, was developed to supply water to Wichita residents and for irrigation in south-central Kansas. Ground-water pumping for city and agricultural use from the aquifer caused water levels to decline in a large part of the aquifer northwest of Wichita. Irrigation pumpage in the area increased substantially during the 1970s and 1980s and accelerated water-level declines. A period of water-level rises associated with greater-than-average precipitation and decreased city pumpage from the area began in 1993. An important factor in the decreased city pumpage was increased use of Cheney Reservoir as a water-supply source by the city of Wichita; as a result, city pumpage from the Equus Beds aquifer during 1993-2005 decreased to quantities similar to those pumped in the 1940s and went from being about 60 percent to about 40 percent of Wichita's water usage. Since 1995, the city also has been investigating the use of artificial recharge in the study area to meet future water-supply needs and to protect the aquifer from the intrusion of saltwater from sources to the west. During January 2006, the direction of ground-water flow in the Equus Beds aquifer in the area was generally from west to east, similar to the direction prior to development of the aquifer. Water-level changes since 1940 for the period January 2003-January 2006 ranged from a decline of more than 36 feet to a rise of more than 2 feet. Almost all wells in the area had small cumulative water-level rises from January 2003 to January 2006 and larger rises from October 1992 (period of maximum storage loss) to January 2006. The water-level rises from October 1992 to January 2006 probably are due principally to decreases in city pumpage, with increases in recharge due to increased precipitation during the period also a contributing factor. Irrigation pumpage increased during the period, so irrigation did not contribute to the rises in water levels between the beginning and end of the period. The storage volume change from October 1992 to January 2006 represents a recovery of about 55 percent of the storage volume previously lost between August 1940 and October 1992.

Increased salt consumption induces body water conservation and decreases fluid intake.

PubMed

Rakova, Natalia; Kitada, Kento; Lerchl, Kathrin; Dahlmann, Anke; Birukov, Anna; Daub, Steffen; Kopp, Christoph; Pedchenko, Tetyana; Zhang, Yahua; Beck, Luis; Johannes, Bernd; Marton, Adriana; Müller, Dominik N; Rauh, Manfred; Luft, Friedrich C; Titze, Jens

2017-05-01

The idea that increasing salt intake increases drinking and urine volume is widely accepted. We tested the hypothesis that an increase in salt intake of 6 g/d would change fluid balance in men living under ultra-long-term controlled conditions. Over the course of 2 separate space flight simulation studies of 105 and 205 days' duration, we exposed 10 healthy men to 3 salt intake levels (12, 9, or 6 g/d). All other nutrients were maintained constant. We studied the effect of salt-driven changes in mineralocorticoid and glucocorticoid urinary excretion on day-to-day osmolyte and water balance. A 6-g/d increase in salt intake increased urine osmolyte excretion, but reduced free-water clearance, indicating endogenous free water accrual by urine concentration. The resulting endogenous water surplus reduced fluid intake at the 12-g/d salt intake level. Across all 3 levels of salt intake, half-weekly and weekly rhythmical mineralocorticoid release promoted free water reabsorption via the renal concentration mechanism. Mineralocorticoid-coupled increases in free water reabsorption were counterbalanced by rhythmical glucocorticoid release, with excretion of endogenous osmolyte and water surplus by relative urine dilution. A 6-g/d increase in salt intake decreased the level of rhythmical mineralocorticoid release and elevated rhythmical glucocorticoid release. The projected effect of salt-driven hormone rhythm modulation corresponded well with the measured decrease in water intake and an increase in urine volume with surplus osmolyte excretion. Humans regulate osmolyte and water balance by rhythmical mineralocorticoid and glucocorticoid release, endogenous accrual of surplus body water, and precise surplus excretion. Federal Ministry for Economics and Technology/DLR; the Interdisciplinary Centre for Clinical Research; the NIH; the American Heart Association (AHA); the Renal Research Institute; and the TOYOBO Biotechnology Foundation. Food products were donated by APETITO, Coppenrath und Wiese, ENERVIT, HIPP, Katadyn, Kellogg, Molda, and Unilever.

Increased salt consumption induces body water conservation and decreases fluid intake

PubMed Central

Rakova, Natalia; Kitada, Kento; Lerchl, Kathrin; Dahlmann, Anke; Birukov, Anna; Daub, Steffen; Kopp, Christoph; Pedchenko, Tetyana; Zhang, Yahua; Beck, Luis; Marton, Adriana; Müller, Dominik N.; Rauh, Manfred; Luft, Friedrich C.

2017-01-01

BACKGROUND. The idea that increasing salt intake increases drinking and urine volume is widely accepted. We tested the hypothesis that an increase in salt intake of 6 g/d would change fluid balance in men living under ultra-long-term controlled conditions. METHODS. Over the course of 2 separate space flight simulation studies of 105 and 205 days’ duration, we exposed 10 healthy men to 3 salt intake levels (12, 9, or 6 g/d). All other nutrients were maintained constant. We studied the effect of salt-driven changes in mineralocorticoid and glucocorticoid urinary excretion on day-to-day osmolyte and water balance. RESULTS. A 6-g/d increase in salt intake increased urine osmolyte excretion, but reduced free-water clearance, indicating endogenous free water accrual by urine concentration. The resulting endogenous water surplus reduced fluid intake at the 12-g/d salt intake level. Across all 3 levels of salt intake, half-weekly and weekly rhythmical mineralocorticoid release promoted free water reabsorption via the renal concentration mechanism. Mineralocorticoid-coupled increases in free water reabsorption were counterbalanced by rhythmical glucocorticoid release, with excretion of endogenous osmolyte and water surplus by relative urine dilution. A 6-g/d increase in salt intake decreased the level of rhythmical mineralocorticoid release and elevated rhythmical glucocorticoid release. The projected effect of salt-driven hormone rhythm modulation corresponded well with the measured decrease in water intake and an increase in urine volume with surplus osmolyte excretion. CONCLUSION. Humans regulate osmolyte and water balance by rhythmical mineralocorticoid and glucocorticoid release, endogenous accrual of surplus body water, and precise surplus excretion. FUNDING. Federal Ministry for Economics and Technology/DLR; the Interdisciplinary Centre for Clinical Research; the NIH; the American Heart Association (AHA); the Renal Research Institute; and the TOYOBO Biotechnology Foundation. Food products were donated by APETITO, Coppenrath und Wiese, ENERVIT, HIPP, Katadyn, Kellogg, Molda, and Unilever. PMID:28414302

Trends in Water Level and Flooding in Dhaka, Bangladesh and Their Impact on Mortality

PubMed Central

Thiele-Eich, Insa; Burkart, Katrin; Simmer, Clemens

2015-01-01

Climate change is expected to impact flooding in many highly populated coastal regions, including Dhaka (Bangladesh), which is currently among the fastest growing cities in the world. In the past, high mortality counts have been associated with extreme flood events. We first analyzed daily water levels of the past 100 years in order to detect potential shifts in extremes. A distributed lag non-linear model was then used to examine the connection between water levels and mortality. Results indicate that for the period of 2003–2007, which entails two major flood events in 2004 and 2007, high water levels do not lead to a significant increase in relative mortality, which indicates a good level of adaptation and capacity to cope with flooding. However, following low water levels, an increase in mortality could be found. As our trend analysis of past water levels shows that minimum water levels have decreased during the past 100 years, action should be taken to ensure that the exposed population is also well-adapted to drought. PMID:25648177

Potential effects of sea-level rise on the depth to saturated sediments of the Sagamore and Monomoy flow lenses on Cape Cod, Massachusetts

USGS Publications Warehouse

Walter, Donald A.; McCobb, Timothy D.; Masterson, John P.; Fienen, Michael N.

2016-05-25

In 2014, the U.S. Geological Survey, in cooperation with the Association to Preserve Cape Cod, the Cape Cod Commission, and the Massachusetts Environmental Trust, began an evaluation of the potential effects of sea-level rise on water table altitudes and depths to water on central and western Cape Cod, Massachusetts. Increases in atmospheric and oceanic temperatures arising, in part, from the release of greenhouse gases likely will result in higher sea levels globally. Increasing water table altitudes in shallow, unconfined coastal aquifer systems could adversely affect infrastructure—roads, utilities, basements, and septic systems—particularly in low-lying urbanized areas. The Sagamore and Monomoy flow lenses on Cape Cod are the largest and most populous of the six flow lenses that comprise the region’s aquifer system, the Cape Cod glacial aquifer. The potential effects of sea-level rise on water table altitude and depths to water were evaluated by use of numerical models of the region. The Sagamore and Monomoy flow lenses have a number of large surface water drainages that receive a substantial amount of groundwater discharge, 47 and 29 percent of the total, respectively. The median increase in the simulated water table altitude following a 6-foot sea-level rise across both flow lenses was 2.11 feet, or 35 percent when expressed as a percentage of the total sea-level rise. The response is nearly the same as the sea-level rise (6 feet) in some coastal areas and less than 0.1 foot near some large inland streams. Median water table responses differ substantially between the Sagamore and Monomoy flow lenses—at 29 and 49 percent, respectively—because larger surface water discharge on the Sagamore flow lens results in increased dampening of the water table response than in the Monomoy flow lens. Surface waters dampen water table altitude increases because streams are fixed-altitude boundaries that cause hydraulic gradients and streamflow to increase as sea-level rises, partially fixing the local water table altitude.The region has a generally thick vadose zone with a mean of about 38 feet; areas with depths to water of 5 feet or less, as estimated from light detection and ranging (lidar) data from 2011 and simulated water table altitudes, currently [2011] occur over about 24.9 square miles, or about 8.4 percent of the total land area of the Sagamore and Monomoy flow lenses, generally in low-lying coastal areas and inland near ponds and streams. Excluding potentially submerged areas, an additional 4.5, 9.8, and 15.9 square miles would have shallow depths to water (5 feet or less) for projected sea-level rises of 2, 4, and 6 feet above levels in 2011. The additional areas with shallow depths to water generally occur in the same areas as the areas with current [2011] depths to water of 5 feet or less: low-lying coastal areas and near inland surface water features. Additional areas with shallow depths to water for the largest sea-level rise prediction (6 feet) account for about 5.7 percent of the total land area, excluding areas likely to be inundated by seawater. The numerous surface water drainages will dampen the response of the water table to sea-level rise. This dampening, combined with the region’s thick vadose zone, likely will mitigate the potential for groundwater inundation in most areas. The potential does exist for groundwater inundation in some areas, but the effects of sea-level rise on depths to water and infrastructure likely will not be substantial on a regional level.

Impact analysis of government investment on water projects in the arid Gansu Province of China

NASA Astrophysics Data System (ADS)

Wang, Zhan; Deng, Xiangzheng; Li, Xiubin; Zhou, Qing; Yan, Haiming

In this paper, we introduced three-nested Constant Elasticity of Substitution (CES) production function into a static Computable General Equilibrium (CGE) Model. Through four levels of factor productivity, we constructed three nested production function of land use productivity in the conceptual modeling frameworks. The first level of factor productivity is generated by the basic value-added land. On the second level, factor productivity in each sector is generated by human activities that presents human intervention to the first level of factor productivity. On the third level of factor productivity, water allocation reshapes the non-linear structure of transaction among first and second levels. From the perspective of resource utilization, we examined the economic efficiency of water allocation. The scenario-based empirical analysis results show that the three-nested CES production function within CGE model is well-behaved to present the economy system of the case study area. Firstly, water scarcity harmed economic production. Government investment on water projects in Gansu thereby had impacts on economic outcomes. Secondly, huge governmental financing on water projects bring depreciation of present value of social welfare. Moreover, water use for environment adaptation pressures on water supply. The theoretical water price can be sharply increased due to the increasing costs of factor inputs. Thirdly, water use efficiency can be improved by water projects, typically can be benefited from the expansion of water-saving irrigation areas even in those expanding dry area in Gansu. Therefore, increasing governmental financing on water projects can depreciate present value of social welfare but benefit economic efficiency for future generation.

Selected hydrologic data for the upper Rio Hondo basin, Lincoln County, New Mexico, 1945-2003

USGS Publications Warehouse

Donohoe, Lisa C.

2004-01-01

Demands for ground and surface water have increased in the upper Rio Hondo Basin due to increases in development and population. Local governments are responsible for land-use and development decisions and, therefore, the governments need information about water resources in their areas. Hydrologic data were compiled for the upper Rio Hondo Basin and water-level data were collected during two synoptic measurements in March and July 2003. Water-level data from March 2003 were contoured and compared with contours constructed in 1963. The 5,600-, 5,700-, and 5,800-foot March 2003 contours indicate that water levels rose. The 5,500-foot contour for March 2003 indicates a decline in water level. The 5,400-foot contour of March 2003 and the 1963 contour mostly coincide, indicating a static water level. The 5,300- and 5,200-foot contours for March 2003 cross the 1963 contours, indicating a decline in water levels near the Rio Ruidoso but a rise in water levels near the Rio Bonito. In eight hydrographs, 2003 water levels are shown to be higher than water levels from the mid- to late 1950's in five of the eight wells. For the same period of record, water levels in the three remaining wells were lower. Rising and declining water levels were highest in the northern part of the study area; the median rise was 4.01 feet and the median decline was 3.51 feet. In the southern part of the study area, the median water-level rise was 2.21 feet and the median decline was 1.56 feet.

Economic impacts of urban flooding in South Florida: Potential consequences of managing groundwater to prevent salt water intrusion.

PubMed

Czajkowski, Jeffrey; Engel, Vic; Martinez, Chris; Mirchi, Ali; Watkins, David; Sukop, Michael C; Hughes, Joseph D

2018-04-15

High-value urban zones in coastal South Florida are considered particularly vulnerable to salt water intrusion into the groundwater-based, public water supplies caused by sea level rise (SLR) in combination with the low topography, existing high water table, and permeable karst substrate. Managers in the region closely regulate water depths in the extensive South Florida canal network to control closely coupled groundwater levels and thereby reduce the risk of saltwater intrusion into the karst aquifer. Potential SLR adaptation strategies developed by local managers suggest canal and groundwater levels may have to be increased over time to prevent the increased salt water intrusion risk to groundwater resources. However, higher canal and groundwater levels cause the loss of unsaturated zone storage and lead to an increased risk of inland flooding when the recharge from rainfall exceeds the capacity of the unsaturated zone to absorb it and the water table reaches the surface. Consequently, higher canal and groundwater levels are also associated with increased risk of economic losses, especially during the annual wet seasons. To help water managers and urban planners in this region better understand this trade-off, this study models the relationships between flood insurance claims and groundwater levels in Miami-Dade County. Via regression analyses, we relate the incurred number of monthly flood claims in 16 Miami-Dade County watersheds to monthly groundwater levels over the period from 1996 to 2010. We utilize these estimated statistical relationships to further illustrate various monthly flood loss scenarios that could plausibly result, thereby providing an economic quantification of a "too much water" trade-off. Importantly, this understanding is the first of its kind in South Florida and is exceedingly useful for regional-scale hydro-economic optimization models analyzing trade-offs associated with high water levels. Copyright © 2017 Elsevier B.V. All rights reserved.

Sustained water-level changes caused by damage and compaction induced by teleseismic earthquakes

NASA Astrophysics Data System (ADS)

Shalev, Eyal; Kurzon, Ittai; Doan, Mai-Linh; Lyakhovsky, Vladimir

2016-07-01

Sustained water-level increase and decrease induced by distant earthquakes were observed in two wells, Gomè 1 and Meizar 1 in Israel. The Gomè 1 well is located within a damage zone of a major fault zone, and Meizar 1 is relatively far from a fault. The monitored pressure change in both wells shows significant water-level oscillations and sustained water-level changes in response to the passage of the seismic waves. The sustained water-level changes include short-term (minutes) undrained behavior and longer-period (hours and days) drained behavior associated with groundwater flow. We model the short-term undrained response of water pressure oscillations and sustained change to the distant 2013 Mw 7.7 Balochistan earthquake by nonlinear elastic behavior of damaged rocks, accounting for small wave-induced compaction and damage accumulation. We suggest that the rocks are close to failure in both locations and strain oscillations produced by the passing seismic waves periodically push the rock above the yield cap, creating compaction when volumetric strain increases and damage when shear strain increases. Compaction increases pore pressure, whereas damage accumulation decreases pore pressure by fracture dilation. The dominant process depends on the properties of the rock. For highly damaged rocks, dilatancy is dominant and a sustained pressure decrease is expected. For low-damage rocks, compaction is the dominant process creating sustained water-level increase. We calculate damage and porosity changes associated to the Balochistan earthquake in both wells and quantify damage accumulation and compaction during the passage of the seismic waves.

Projections of extreme water level events for atolls in the western Tropical Pacific

NASA Astrophysics Data System (ADS)

Merrifield, M. A.; Becker, J. M.; Ford, M.; Yao, Y.

2014-12-01

Conditions that lead to extreme water levels and coastal flooding are examined for atolls in the Republic of the Marshall Islands based on a recent field study of wave transformations over fringing reefs, tide gauge observations, and wave model hindcasts. Wave-driven water level extremes pose the largest threat to atoll shorelines, with coastal levels scaling as approximately one-third of the incident breaking wave height. The wave-driven coastal water level is partitioned into a mean setup, low frequency oscillations associated with cross-reef quasi-standing modes, and wind waves that reach the shore after undergoing high dissipation due to breaking and bottom friction. All three components depend on the water level over the reef; however, the sum of the components is independent of water level due to cancelling effects. Wave hindcasts suggest that wave-driven water level extremes capable of coastal flooding are infrequent events that require a peak wave event to coincide with mid- to high-tide conditions. Interannual and decadal variations in sea level do not change the frequency of these events appreciably. Future sea-level rise scenarios significantly increase the flooding threat associated with wave events, with a nearly exponential increase in flooding days per year as sea level exceeds 0.3 to 1.0 m above current levels.

Arsenic levels in cutaneous appendicular organs are correlated with digitally evaluated hyperpigmented skin of the forehead but not the sole in Bangladesh residents.

PubMed

Yajima, Ichiro; Ahsan, Nazmul; Akhand, Anwarul Azim; Al Hossain, Mm Aeorangajeb; Yoshinaga, Masafumi; Ohgami, Nobutaka; Iida, Machiko; Oshino, Reina; Naito, Mariko; Wakai, Kenji; Kato, Masashi

2018-01-01

There has been no report showing the effect of arsenic level on digitized skin pigmentation level, a typical diagnostic marker for arsenicosis. Correlations among history of drinking well water, arsenic levels in hair and toenails, and digitalized skin pigmentation levels (L*-value) in sunlight-exposed (forehead) and unexposed (sole) skin areas digitally evaluated by using a reflectance spectrophotometer were examined in 150 residents of Bangladesh. Univariate analysis showed that arsenic levels in hair and toenails of subjects with a history of drinking well water were 10.6-fold and 7.1-fold higher, respectively, than those in subjects without a history of drinking well water. The mean L*-value of foreheads, but not that of soles, in subjects with a history of drinking well water was 1.15-fold lower (more pigmented) than that in subjects without a history of drinking well water. Significant correlations were found between duration of drinking well water and arsenic concentrations in hair (r=0.63; P<0.01) and toenails (r=0.60; P<0.01). Multivariate analysis showed that the arsenic levels in hair and toenails and the duration of drinking well water were strongly correlated with the digitized pigmented level of the forehead but not that of the sole. An increase in the duration of drinking well water may increase hyperpigmentation in the forehead, but not that in the sole, through an increased arsenic level in the human body as shown in cutaneous appendicular organs (hair and toenails).

Beneficial effects of coconut water feeding on lipid metabolism in cholesterol-fed rats.

PubMed

Sandhya, V G; Rajamohan, T

2006-01-01

The purpose of this study was to determine the effect of coconut water feeding in cholesterol-fed rats. Male albino rats were fed tender coconut water and mature coconut water at a dose level of 4 mL/100 g of body weight. Cholesterol feeding caused a marked increase in total cholesterol, very low-density lipoprotein (VLDL) + low-density lipoprotein (LDL) cholesterol, and triglycerides in serum. Administration of coconut water counteracts the increase in total cholesterol, VLDL + LDL cholesterol, and triglycerides, while high-density lipoprotein cholesterol was higher. Lipid levels in the tissues viz. liver, heart, kidney, and aorta were markedly decreased in cholesterol-fed rats supplemented with coconut water. Feeding coconut water resulted in increased activities of 3-hydroxy-3-methylglutaryl-CoA reductase in liver, lipoprotein lipase in heart and adipose tissue, and plasma lecithin:cholesterol acyl transferase, while lipogenic enzymes showed decreased activities. An increased rate of cholesterol conversion to bile acid and an increased excretion of bile acids and neutral sterols were observed in rats fed coconut water. Histopathological studies of liver and aorta revealed much less fatty accumulation in these tissues in cholesterol-fed rats supplemented with coconut water. Feeding coconut water resulted in increased plasma L-arginine content, urinary nitrite level, and nitric oxide synthase activity. These results indicate that both tender and mature coconut water has beneficial effects on serum and tissue lipid parameters in rats fed cholesterol-containing diet.

Simulation of projected water demand and ground-water levels in the Coffee Sand and Eutaw-McShan aquifers in Union County, Mississippi, 2010 through 2050

USGS Publications Warehouse

Hutson, Susan S.; Strom, E.W.; Burt, D.E.; Mallory, M.J.

2000-01-01

Ground water from the Eutaw-McShan and the Coffee Sand aquifers is the major source of supply for residential, commercial, and industrial purposes in Union County, Mississippi. Unbiased, scientifically sound data and assessments are needed to assist agencies in better understanding and managing available water resources as continuing development and growth places more stress on available resources. The U.S. Geological Survey, in cooperation with the Tennessee Valley Authority, conducted an investigation using water-demand and ground-water models to evaluate the effect of future water demand on groundwater levels. Data collected for the 12 public-supply facilities and the self-supplied commercial and industrial facilities in Union County were used to construct water-demand models. The estimates of water demand to year 2050 were then input to a ground-water model based on the U.S. Geological Survey finite-difference computer code, MODFLOW. Total ground-water withdrawals for Union County in 1998 were estimated as 2.85 million gallons per day (Mgal/d). Of that amount, municipal withdrawals were 2.55 Mgal/d with about 1.50 Mgal/d (59 percent) delivered to residential users. Nonmunicipal withdrawals were 0.296 Mgal/d. About 80 percent (2.27 Mgal/d) of the total ground-water withdrawal is produced from the Eutaw-McShan aquifer and about 13 percent (0.371 Mgal/d) from the Coffee Sand aquifer. Between normal- and high-growth conditions, total water demand could increase from 72 to 131 percent (2.9 Mgal/d in 1998 to 6.7 Mgal/d in year 2050) with municipal demand increasing from 77 to 146 percent (2.6 to 6.4 Mgal/d). Increased pumping to meet the demand for water was simulated to determine the effect on water levels in the Coffee Sand and Eutaw- McShan aquifers. Under baseline-growth conditions, increased water use by year 2050 could result in an additional 65 feet of drawdown in the New Albany area below year 2000 water levels in the Coffee Sand aquifer and about 120 feet of maximum drawdown in the Eutaw-McShan aquifer. Under normal-growth conditions, increased water use could result in an additional 65 feet of drawdown in the New Albany area below year 2000 water levels in the Coffee Sand aquifer and about 135 feet of maximum drawdown in the Eutaw-McShan aquifer. Under high-growth conditions, increased water use could result in 75 feet of drawdown in the New Albany area below year 2000 water levels in the Coffee Sand aquifer and about 190 feet of maximum drawdown in the Eutaw-McShan aquifer. The resulting highgrowth projected water level for the year 2050 at the center of the drawdown cone in the New Albany area is between 450 and 500 feet above the top of the Eutaw-McShan aquifer.

Interactive effects of dietary palm oil concentration and water temperature on lipid digestibility in rainbow trout, Oncorhynchus mykiss.

PubMed

Ng, Wing-Keong; Campbell, Patrick J; Dick, James R; Bell, J Gordon

2003-10-01

An experiment was conducted to evaluate the interactive effects of dietary crude palm oil (CPO) concentration and water temperature on lipid and FA digestibility in rainbow trout. Four isolipidic diets with 0, 5, 10, or 20% (w/w) CPO, at the expense of fish oil, were formulated and fed to groups of trout maintained at water temperatures of 7, 10, or 15 degrees C. The apparent digestibility (AD) of the FA, measured using yttrium oxide as an inert marker, decreased with increasing chain length and increased with increasing unsaturation within each temperature regimen irrespective of CPO level fed to the fish. PUFA of the n-3 series were preferentially absorbed compared to n-6 PUFA in all diet and temperature treatments. Except for a few minor FA, a significant (P < 0.05) interaction between diet and temperature effects on FA digestibility was found. Increasing dietary levels of CPO lead to significant reductions in the AD of saturates and, to a lesser extent, also of the other FA. Lowering water temperature reduced total saturated FA digestibility in trout regardless of CPO level. Based on the lipid class composition of trout feces, this reduction in AD of saturates was due in part to the increasing resistance of dietary TAG to digestion. Increasing CPO level and decreasing water temperature significantly increased TAG content in trout fecal lipids, with saturates constituting more than 60% of the FA composition. Total monoene and PUFA digestibilities were not significantly affected by water temperature in fish fed up to 10% CPO in their diet. The potential impact of reduced lipid and FA digestibility in cold-water fish fed diets supplemented with high levels of CPO on fish growth performance requires further research.

Changes in Water Levels and Storage in the High Plains Aquifer, Predevelopment to 2005

USGS Publications Warehouse

McGuire, V.L.

2007-01-01

The High Plains aquifer underlies 111.4 million acres (174,000 square miles) in parts of eight States-Colorado, Kansas, Nebraska, New Mexico, Oklahoma, South Dakota, Texas, and Wyoming. The area overlying the High Plains aquifer is one of the major agricultural regions in the world. Water-level declines began in parts of the High Plains aquifer soon after the beginning of extensive ground-water irrigation. By 1980, water levels in the High Plains aquifer in parts of Texas, Oklahoma, and southwestern Kansas had declined more than 100 feet (Luckey and others, 1981). In response to these water-level declines, the U.S. Geological Survey (USGS), in cooperation with numerous Federal, State, and local water-resources agencies, began monitoring more than 7,000 wells in 1988 to assess annual water-level change in the aquifer. A report by the USGS, 'Water-Level Changes in the High Plains Aquifer, Predevelopment to 2005 and 2003 to 2005' (McGuire, 2007), shows the areas of substantial water-level changes in the aquifer from the time prior to substantial ground-water irrigation development (predevelopment or about 1950) to 2005 (fig. 1). In parts of the area, farmers began using ground water for irrigation extensively in the 1930s and 1940s. Estimated irrigated acreage in the area overlying the High Plains aquifer increased rapidly from 1940 to 1980 and changed slightly from 1980 to 2002: 1949-2.1 million acres, 1980-13.7 million acres, 1997-13.9 million acres, 2002-12.7 million acres. Irrigated acres in 2002 were 12 percent of the aquifer area, not including the areas with little or no saturated thickness (McGuire, 2007). Ground-water withdrawals for irrigation and other uses are compiled and reported by the USGS and agencies in each State about every 5 years. Ground-water withdrawals from the High Plains aquifer for irrigation increased from 4 to 19 million acre-feet from 1949 to 1974. Ground-water withdrawals for irrigation in 1980, 1985, 1990, and 1995 were from 4 to 18 percent less than withdrawals for irrigation in 1974. Ground-water withdrawals from the aquifer for irrigation in 2000 were 21 million acre-feet (McGuire, 2007). Water-level changes in the aquifer result from an imbalance between discharge and recharge. Discharge is primarily ground-water withdrawals for irrigation. Discharge also includes evapotranspiration, where the water table is near the land surface, and seepage to streams and springs, where the water table intersects with the land surface. Recharge is primarily from precipitation. Other sources of recharge are irrigation return flow and seepage from streams, canals, and reservoirs. Water-level declines may result in increased costs for ground-water withdrawals because of increased pumping lift and decreased well yields (Taylor and Alley, 2001). Water-level declines also can affect ground-water availability, surface-water flow, and near-stream (riparian) habitat areas (Alley and others, 1999).

Ground-water resources in the lower Milliken--Sarco--Tulucay Creeks area, southeastern Napa County, California, 2000-2002

USGS Publications Warehouse

Farrar, Christopher D.; Metzger, Loren F.

2003-01-01

Ground water obtained from individual private wells is the sole source of water for about 4,800 residents living in the lower Milliken-Sarco-Tulucay Creeks area of southeastern Napa County. Increases in population and in irrigated vineyards during the past few decades have increased water demand. Estimated ground-water pumpage in 2000 was 5,350 acre-feet per year, an increase of about 80 percent since 1975. Water for agricultural irrigation is the dominant use, accounting for about 45 percent of the total. This increase in ground-water extraction has resulted in the general decline of ground-water levels. The purpose of this report is to present selected hydrologic data collected from 1975 to 2002 and to quantify changes in the ground-water system during the past 25 years. The study area lies in one of several prominent northwest-trending structural valleys in the North Coast Ranges. The area is underlain by alluvial deposits and volcanic rocks that exceed 1,000 feet in thickness in some places. Alluvial deposits and tuff beds in the volcanic sequence are the principal source of water to wells. The ground-water system is recharged by precipitation that infiltrates, in minor amounts, directly on the valley floor but mostly by infiltration in the Howell Mountains. Ground water moves laterally from the Howell Mountains into the study area. Although the area receives abundant winter precipitation in most years, nearly half of the precipitation is lost as surface runoff to the Napa River. Evapotranspiration also is high, accounting for nearly one-half of the total precipitation received. Because of the uncertainties in the estimates of precipitation, runoff, and evapotranspiration, a precise estimate of potential ground-water recharge cannot be made. Large changes in ground-water levels occurred between 1975 and 2001. In much of the western part of the area, water levels increased; but in the central and eastern parts, water levels declined by 25 to 125 feet. Ground-water extraction produced three large pumping depressions in the northern and east-central parts of the area. The general decline in ground-water levels is a result of increases in ground-water pumpage and possibly changes in infiltration capacity caused by changes in land use. Ground-water-level declines during 1960-2002 are evident in the records for 9 of 10 key monitoring wells. In five of these wells, water levels dropped by greater than 20 feet since the 1980s. The largest water-level declines have occurred since the mid 1970s, corresponding with a period of accelerated well construction and ground-water extraction. Analysis of samples from 15 wells indicates that the chemical quality of ground water in the study generally is acceptable. However, arsenic concentrations in samples from five wells exceed the U.S. Environmental Protection Agency primary drinking-water standard of 10 micrograms per liter, and iron concentrations in samples from five wells exceed the U.S. Environmental Protection Agency and the California Department of Health Services secondary drinking-water standard of 300 micrograms per liter. Water from 12 of 15 wells sampled contained concentrations of manganese that exceed the U.S. Environmental Protection Agency and the California Department of Health Services secondary drinking-water standard of 50 micrograms per liter. Two wells produced water that had boron in excess of the California Department of Health Services action level of 1 milligram per liter. Stable isotope, chlorofluorocarbon, and tritium data indicate that ground water in the area is a mixture of waters that recharged the aquifer system at different times. The presence of chlorofluorocarbons and tritium in water from the study area is evidence that modern recharge (post 1950) does take place. Water-temperature logs indicate that ground-water temperatures throughout the study area exceed 30?C at depths in excess of 600 feet. Further, water at

Ground-water hydrology of the upper Sevier River Basin, south-central Utah, and simulation of ground-water flow in the valley-fill in Panguitch Valley.

USGS Publications Warehouse

Thiros, Susan A.; Brothers, William C.

1993-01-01

The ground-water hydrology of the upper Sevier River basin, primarily of the unconsolidated valley-fill aquifers, was studied from 1988 to 1989. Recharge to the valley-fill aquifers is mostly by seepage from surface-water sources. Changes in soil-moisture content am water levels were measured in Panguitch Valley both at a flood-irrigated and at a sprinkler-irrigated alfalfa field to quantify seepage from unconsumed irrigation water. Lag time between irrigation and water-level response decreased from 6 to 2 days in the flood-irrigated field as the soil-moisture content increased. Water levels measured in the sprinkler-irrigated field did not respond to irrigation. Discharge from the valley-fill aquifer to the Sevier River in Panguitch Valley is about 53,570 acre-feet per year.Water levels measured in wells from 1951 to 1989 tend to fluctuate with the quantity of precipitation falling at higher elevations. Ground-water discharge to the Sevier River in Panguitch Valley causes a general increase in the specific conductance of the river in a downstream direction.A three-layered ground-water-flow model was used to simulate the effects of changes in irrigation practices am increased ground-water withdrawals in Panguitch Valley. The establishment of initial conditions consisted of comparing simulated water levels and simulated gains and losses from the Sevier River and selected canals with values measured during the 1988 irrigation season. The model was calibrated by comparing water-level changes measured from 1961 to 1963 to simulated changes. A simulated change from flood to sprinkler irrigation resulted in a maximum decline in water level of 0.9 feet after the first year of change. Simulating additional discharge from wells resulted in drawdowns of about 20 feet after the first year of pumping.

Evaluation of the Source and Transport of High Nitrate Concentrations in Ground Water, Warren Subbasin, California

USGS Publications Warehouse

Nishikawa, Tracy; Densmore, Jill N.; Martin, Peter; Matti, Jonathan

2003-01-01

Ground water historically has been the sole source of water supply for the Town of Yucca Valley in the Warren subbasin of the Morongo ground-water basin, California. An imbalance between ground-water recharge and pumpage caused ground-water levels in the subbasin to decline by as much as 300 feet from the late 1940s through 1994. In response, the local water district, Hi-Desert Water District, instituted an artificial recharge program in February 1995 using imported surface water to replenish the ground water. The artificial recharge program resulted in water-level recoveries of as much as 250 feet in the vicinity of the recharge ponds between February 1995 and December 2001; however, nitrate concentrations in some wells also increased from a background concentration of 10 milligrams per liter to more than the U.S. Environmental Protection Agency (USEPA) maximum contaminant level (MCL) of 44 milligrams per liter (10 milligrams per liter as nitrogen). The objectives of this study were to: (1) evaluate the sources of the high-nitrate concentrations that occurred after the start of the artificial-recharge program, (2) develop a ground-water flow and solute-transport model to better understand the source and transport of nitrates in the aquifer system, and (3) utilize the calibrated models to evaluate the possible effect of a proposed conjunctive-use project. These objectives were accomplished by collecting water-level and water-quality data for the subbasin and assessing changes that have occurred since artificial recharge began. Collected data were used to calibrate the ground-water flow and solute-transport models. Data collected for this study indicate that the areal extent of the water-bearing deposits is much smaller (about 5.5 square miles versus 19 square miles) than that of the subbasin. These water-bearing deposits are referred to in this report as the Warren ground-water basin. Faults separate the ground-water basin into five hydrogeologic units: the west, the midwest, the mideast, the east and the northeast hydrogeologic units. Water-quality analyses indicate that septage from septic tanks is the primary source of the high-nitrate concentrations measured in the Warren ground-water basin. Water-quality and stable-isotope data, collected after the start of the artificial recharge program, indicate that mixing occurs between imported water and native ground water, with the highest recorded nitrate concentrations in the midwest and the mideast hydrogeologic units. In general, the timing of the increase in measured nitrate concentrations in the midwest hydrogeologic unit is directly related to the distance of the monitoring well from a recharge site, indicating that the increase in nitrate concentrations is related to the artificial recharge program. Nitrate-to-chloride and nitrogen-isotope data indicate that septage is the source of the measured increase in nitrate concentrations in the midwest and the mideast hydrogeologic units. Samples from four wells in the Warren ground-water basin were analyzed for caffeine and selected human pharmaceutical products; these analyses suggest that septage is reaching the water table. There are two possible conceptual models that explain how high-nitrate septage reaches the water table: (1) the continued downward migration of septage through the unsaturated zone to the water table and (2) rising water levels, a result of the artificial recharge program, entraining septage in the unsaturated zone. The observations that nitrate concentrations increase in ground-water samples from wells soon after the start of the artificial recharge program in 1995 and that the largest increase in nitrate concentrations occur in the midwest and mideast hydrogeologic units where the largest increase in water levels occur indicate the validity of the second conceptual model (rising water levels). The potential nitrate concentration resulting from a water-level rise in the midwest and

Doubling of coastal flooding frequency within decades due to sea-level rise

USGS Publications Warehouse

Vitousek, Sean; Barnard, Patrick L.; Fletcher, Charles H.; Frazer, Neil; Erikson, Li; Storlazzi, Curt D.

2017-01-01

Global climate change drives sea-level rise, increasing the frequency of coastal flooding. In most coastal regions, the amount of sea-level rise occurring over years to decades is significantly smaller than normal ocean-level fluctuations caused by tides, waves, and storm surge. However, even gradual sea-level rise can rapidly increase the frequency and severity of coastal flooding. So far, global-scale estimates of increased coastal flooding due to sea-level rise have not considered elevated water levels due to waves, and thus underestimate the potential impact. Here we use extreme value theory to combine sea-level projections with wave, tide, and storm surge models to estimate increases in coastal flooding on a continuous global scale. We find that regions with limited water-level variability, i.e., short-tailed flood-level distributions, located mainly in the Tropics, will experience the largest increases in flooding frequency. The 10 to 20 cm of sea-level rise expected no later than 2050 will more than double the frequency of extreme water-level events in the Tropics, impairing the developing economies of equatorial coastal cities and the habitability of low-lying Pacific island nations.

Cyclic fluctuations of water level as a basis for determining aquifer transmissibility

USGS Publications Warehouse

Ferris, John G.

1952-01-01

In coastal areas, wells near bodies of tidal water frequently exhibit sinusoidal fluctuations of water level, in response to periodic changes of tidewater stage.  Inland, the regulation of a surface reservoir often produces correlative changes of ground-water stage in wells adjacent either to the reservoir or to its attendant stream.  As the stage of the surface water rises, the head upon the subaqueous outcrop of the aquifer increases and thereby either increases the rate of inflow to the aquifer or reduces the rate of outflow therefrom.  The increase in recharge or reduction in discharge results in a general recovery of water level in the aquifer. On the subsequent falling stage this pattern is reversed.  When the stage of the surface body fluctuates as a simple harmonic motion a train of sinusoidal waves is propagated shoreward through the sub-outcrop of the aquifer.  With increasing distance from the sub-outcrop, the amplitude of the transmitted wave decreases and the time lag of a given maximum or minimum increases.

Water-Level Data for the Albuquerque Basin and Adjacent Areas, Central New Mexico, Period of Record Through 2004

USGS Publications Warehouse

DeWees, R.K.

2006-01-01

The Albuquerque Basin, located in central New Mexico, is about 100 miles long and 25 to 40 miles wide. The basin is defined as the extent of consolidated and unconsolidated deposits of Tertiary and Quaternary age that encompass the structural Rio Grande Rift within the basin. Drinking-water supplies throughout the Albuquerque Basin are obtained solely from ground-water resources. An increase of approximately 20 percent in the population from 1991 to present also resulted in an increased demand for water. From April 1982 through September 1983, a network of wells was established to monitor changes in ground-water levels throughout the Albuquerque Basin. This network consisted of 6 wells with analog-to-digital recorders and 27 wells where water levels were measured monthly. Currently (2004), the network consists of 234 wells and piezometers. This report presents water-level data collected by U.S. Geological Survey personnel at 155 sites through 2004. Water-level and other data for 71 sites are collected by other agencies. Water-level data for 8 sites of the 155 sites measured by the U.S. Geological Survey were not available for this report.

Simulated response of the Sparta Aquifer to outcrop area recharge augmentation, southeastern Arkansas

USGS Publications Warehouse

Hays, Phillip D.

2001-01-01

Recharge augmentation by construction of infiltration impoundments is a potential means of increasing aquifer water levels and aquifer yield that is under consideration for the Sparta aquifer in southeastern Arkansas. The aquifer is a major water resource for municipal, industrial, and agricultural uses, and approximately 287 million gallons per day was pumped from the aquifer in Arkansas in 1995; this is double the amount pumped in 1975. Historically, the Sparta aquifer has provided abundant water of high quality. In recent years, however, the demand for water in some areas has resulted in withdrawals from the Sparta that significantly exceed recharge to the aquifer, and considerable declines have occurred in the potentiometric surface. To better manage the Sparta aquifer, water users in Arkansas are evaluating and implementing a variety of management practices and assessing alternative, surface-water sources to reduce stress upon the Sparta aquifer. One approach to managing and maximizing use of the Sparta aquifer is augmenting recharge to the aquifer by construction of infiltration lakes or canals within the recharge area. The basic concept of augmented recharge is simply to increase the amount of water being introduced into the aquifer so that more water will be available for use. Ground-water flow model simulations were conducted to assess the effectiveness of constructing lakes or canals to augment recharge. Results show that construction of five new lakes in the Sparta recharge area upgradient from major pumping centers or construction of a series of canals along the length of the recharge area yield notable benefit to aquifer conditions when compared with simulations entailing no augmentation of recharge. Augmentation of recharge in the Sparta aquifer with emplacement of lakes provides slight increase to aquifer water levels. The presence of the lakes increased simulated aquifer water levels 0.5 foot or more across a broad area comprising all or a substantial part of 19 counties after the 30-year simulation period. Substantial increases of 5 feet or greater are limited to a smaller area proximal to the lakes. Increases of 5 feet or more are seen in El Dorado, Pine Bluff, and Stuttgart. The positive effect of the lakes on aquifer water levels is rapidly realized after emplacement of the lakes. For example, in the El Dorado area more than 3 feet of a total of 8 feet of water-level increase is seen in the first 5 years of the simulation; in the Pine Bluff area 9 feet of a total of 16 feet of increase occurs within 5 years. Sustainable yield from the aquifer could be expected to be increased within the zone of influence of the lakes. Augmentation of recharge in the Sparta aquifer with emplacement of canals provides considerable increase of aquifer water levels. The zone of influence in the aquifer with canal-augmented recharge extends from the recharge area eastward to the Mississippi River. Aquifer water levels exhibit an increase of 5 feet or more across a broad area comprising all or a substantial part of 15 counties. Increases of 20 feet or more are seen in El Dorado, Pine Bluff, and Stuttgart. The amount of water moving into the aquifer is substantially increased under this scenario, and the amount of water removed from storage is decreased, thereby, increasing aquifer conditions considerably. Sustainable yield from the aquifer could be expected to be greater within the zone of influence of the canals as compared to either the scenario without recharge augmentation or recharge augmentation with lakes. The effect of the canal on aquifer water levels is rapidly realized after emplacement of the canals. For example, in the El Dorado area, 22 feet of a total of 30 feet of increase is seen in the first 5 years of the simulation; in the Pine Bluff area, 15 feet of a total of 24 feet of increase occurs within 5 years. As constructed, the model simulations imply that any lakes or canals constructed would maintain exce

Reducing production of taste and odor by deep-living cyanobacteria in drinking water reservoirs by regulation of water level.

PubMed

Su, Ming; Jia, Dongmin; Yu, Jianwei; Vogt, Rolf D; Wang, Jingshi; An, Wei; Yang, Min

2017-01-01

Abatement and control of algae, producing toxins and creating taste & odor (T&O) in drinking water sources, is a major challenge for water supply. In this study we proposed a strategy based on water level regulation for the control of odor-producing cyanobacteria in source water. Miyun Reservoir, the main surface water source for Beijing, has been suffering from 2-methylisoborneol (2-MIB) induced T&O problems caused by deep-living Planktothrix sp. since 2002. The biomass of deep-living Planktothrix in Miyun Reservoir was found to be mainly governed by the water depth above its sediment habitat. An algorithm for water level regulation aiming to minimize the risk for T&O in different types of reservoirs is proposed. The study demonstrates that risk for T&O can be minimized by increasing the water level in Miyun Reservoir. The high-risk area can be reduced by about 2.91% (0.61% to 5.76%) of surface area for each meter increase in the water level, when the water level is lower than 145m. More specifically, the water level needs to be raised to higher than 147.7ma.s.l. from 131.0m in order to obtain an acceptable risk level (ARL) of 10%. This management strategy to abate T&O problems is simpler and cheaper to implement compared to traditional physical, chemical and biological techniques. Moreover, it has no apparent negative impact on water quality and aquatic organisms. Copyright © 2016. Published by Elsevier B.V.

Compounding Impacts of Climate Change and Increased Human Water Withdrawal on Urmia Lake Water Availability

NASA Astrophysics Data System (ADS)

Alborzi, A.; Moftakhari, H.; Azaranfar, A.; Mallakpour, I.; Ashraf, B.; AghaKouchak, A.

2017-12-01

In recent decades, climate change and increase in human water withdrawal, combined, have caused ecological degradation in several terminal lakes worldwide. Among them, the shallow and hyper-saline Urmia Lake in Iran has experienced about 6 meters drawdown in lake level and 80% reduction in surface area. Here, we assess the imposed stress on Urmia Basin's water availability and Lake's ecological condition in response to coupled climate change and human-induced water withdrawal. A generalized river basin decision support system model consisting network flow is developed to simulate the basin-lake interactions under a wide range of scenarios. This model explicitly includes water management infrastructure, reservoirs, and irrigation and municipal water use. Studied scenarios represent a wide range of historic climate and water use scenarios including a historical baseline, future increase in water demand, and also improved water efficiency. In this presentation, we show the lake's water level, as a measure of lake's ecological health, under the compounding effects of the climate condition (top-down) and water use (bottom-up) scenarios. This method illustrates what combinations lead to failure in meeting the lake's ecological level.

Influence of freezing and thawing on the hydration characteristics, quality, and consumer acceptance of whole muscle beef injected with solutions of salt and phosphate.

PubMed

Pietrasik, Z; Janz, J A M

2009-03-01

Effects of salt/phosphate injection level (112% or 125% pump), salt level (0.5% or 1.5% salt), and freezing/thawing on hydration characteristics, quality, and consumer acceptance of beef semitendinosus were investigated. All enhancement treatments decreased shear force by 25-35%, but negatively affected colour. Increased salt concentration yielded lower purge and cooking losses, and higher water holding capacity. The higher injection level reduced water binding properties, however, the loss in functionality with higher water addition was overcome with increased salt content. Freezing and subsequent thawing was generally detrimental to colour and water binding properties and tended to increase shear force. Freezing and subsequent thawing did not affect fluid release in steaks held for 1 day before analysis, but resulted in decreased water retention in samples held for 7 days. Holding vacuum packaged steaks for 7 days generally increased package purge and negatively affected colour parameters, although water binding characteristics were improved. Consumer panel results demonstrated a negative effect on juiciness and tenderness where meat subject to low salt/high injection was frozen then thawed - the low salt level was insufficient to maintain any positive effect of injection treatment. In general, salt/phosphate injection improved product acceptability and increased willingness to purchase.

Statistical summaries of ground-water level data collected in the Suwannee River Water Management District, 1948 to 1994

USGS Publications Warehouse

Collins, J.J.; Freeman, L.D.

1996-01-01

Since 1948, ground-water level data have beensystematically collected from selected wells in theSuwannee River Water Management District (SRWMD) by the U.S. Geological Survey (USGS),the SRWMD, and other agencies. Records of waterlevels in the SRWMD (fig. 1), collected by the USGS and SRWMD through 1990, and by the SRWMD from 1990 to 1994, have been published for many years in the USGS annual report series "Water Resources Data for Florida." However, no systematic statistical summaries of water levels in the SRWMD have been previously published. The need for such statistical summary data forevaluations of drought severity, ground-water supplyavailability, and minimum water levels for regulatory purposes increases daily as demands for ground-water usage increase. Also, much of the base flow of the Suwannee River is dependent upon ground water. As the population and demand for ground water for drinking water and irrigation purposes increase, the ability to quickly and easily predict trends in ground-water availability will become paramount. In response to this need, the USGS, in cooperation with the SRWMD, compiled this report. Ground-water sta tistics for 136 sites are presented as well as figures showing water levels that were measured in wells from 1948 through September 1994. In 1994, the SRWMD and the USGS began a long- term program of cooperative studies designed tobetter understand minimum and maximum streamflows and ground-water levels in the SRWMD. Minimum and maximum flows and levels are needed by the district to manage the surface- and ground-water resources of the SRWMD and to maintain or improve the various ecosystems. Data evaluation was a necessary first step in the long- term SRWMD ground-water investigations program, because basic statistics for ground-water levels are not included in the USGS annual data reports such as "Water Resources Data for Florida, Water Year 1994" (Fran klin and others, 1995). Statistics included in this report were generated using the USGS computer pro gram ADAPS (Automatic Data Processing System) to characterize normal ground-water levels and depar tures from normal. The report has been organized so that the statisti cal analyses of water levels in the wells are presentedfollowing this introductory material, a description ofthe hydrogeology in the study area, and a description of the statistics used to present the water-level data. Specifically, the report presents statistical analyses for each well, as appropriate, in the following manner: Description of the well.Hydrographs of ground-water levels for the period of record, for the last 10 years of record, and for the last 5 years of record. Graphs of maximum, minimum, and mean of monthly mean ground-water levels for wells with 5 or more years of record.Frequency hydrographs (25, 50, and 75 percent) of monthly mean ground-water levels for wells with 5 or more years of record. Water-level data and statistical plots are grouped by county and sorted within the county by ascendingsite identification number. Well locations are plottedon county maps preceding the well descriptions andhydrographs.

Potentiometric Surface of the Aquia Aquifer in Southern Maryland, September 2007

USGS Publications Warehouse

Curtin, Stephen E.; Andreasen, David C.; Staley, Andrew W.

2009-01-01

This report presents a map showing the potentiometric surface of the Aquia aquifer in the Aquia Formation of Paleocene age in Southern Maryland during September 2007. The map is based on water-level measurements in 85 wells. The highest measured water level was 50 feet above sea level near the northern boundary and outcrop area of the aquifer in the central part of Anne Arundel County, and was below sea level just south of this area and in the remainder of the study area. The hydraulic gradient increased southeastward toward an extensive cone of depression around well fields at Lexington Park and Solomons Island. A water level measured west of the Cheasapeake Beach area has declined to 57 feet below sea level due to increased withdrawals. The lowest water level measured was 162 feet below sea level at the center of a cone of depression at Lexington Park.

Assessing water scarcity in agricultural production system based on the generalized water resources and water footprint framework.

PubMed

Xinchun, Cao; Mengyang, Wu; Xiangping, Guo; Yalian, Zheng; Yan, Gong; Nan, Wu; Weiguang, Wang

2017-12-31

An indicator, agricultural water stress index (AWSI), was established based blue-green water resources and water footprint framework for regional water scarcity in agricultural production industry evaluation. AWSI is defined as the ratio of the total agricultural water footprint (AWF) to water resources availability (AWR) in a single year. Then, the temporal and spatial patterns of AWSI in China during 1999-2014 were analyzed based on the provincial AWR and AWF quantification. The results show that the annual AWR in China has been maintained at approximately 2540Gm 3 , of which blue water accounted for >70%. The national annual AWF was approximately 1040Gm 3 during the study period and comprised 65.6% green, 12.7% blue and 21.7% grey WFs The space difference in both the AWF for per unit arable land (AWFI) and its composition was significant. National AWSI was calculated as 0.413 and showed an increasing trend in the observed period. This index increased from 0.320 (mid-water stress level) in 2000 to 0.490 (high water stress level) in the present due to the expansion of the agricultural production scale. The Northern provinces, autonomous regions and municipalities (PAMs) have been facing high water stress, particularly the Huang-Huai-Hai Plain, which was at a very high water stress level (AWSI>0.800). Humid South China faces increasingly severe water scarcity, and most of the PAMs in the region have converted from low water stress level (AWSI=0.100-0.200) to mid water stress level (AWSI=0.200-0.400). The AWSI is more appropriate for reflecting the regional water scarcity than the existing water stress index (WSI) or the blue water scarcity (BWS) indicator, particularly for the arid agricultural production regions due to the revealed environmental impacts of agricultural production. China should guarantee the sustainable use of agricultural water resources by reducing its crop water footprint. Copyright © 2017 Elsevier B.V. All rights reserved.

Tidal fluctuations influence E. coli concentrations in urban estuaries.

PubMed

Jovanovic, Dusan; Coleman, Rhys; Deletic, Ana; McCarthy, David T

2017-06-15

This study investigated the influence of water level and velocity on Escherichia coli levels over multiple tidal cycles in an urban microtidal estuary in Melbourne, Australia. Over 3,500 E. coli samples and high resolution water level and velocity measurements from two locations within the estuary were used for the analysis. E. coli negatively correlated with water level in the upper estuary which was proposed to be linked to increased resuspension of estuarine sediments during low tide. No relationship was found in the lower estuary, likely due to wet weather inputs dwarfing subtler tidal-related processes. Removal of wet weather data enabled significant relationships to emerge in the lower estuary: 1) positive with water level (when a 9-h shift applied corresponding to the phase shift between water levels and velocities) and; 2) positive with velocity (no shift applied). This supports a link between increased E. coli levels and tidal-related resuspension. Copyright © 2017 Elsevier Ltd. All rights reserved.

The unintended energy impacts of increased nitrate contamination from biofuels production.

PubMed

Twomey, Kelly M; Stillwell, Ashlynn S; Webber, Michael E

2010-01-01

Increases in corn cultivation for biofuels production, due to the Energy Independence and Security Act of 2007, are likely to lead to increases in nitrate concentrations in both surface and groundwater resources in the United States. These increases might trigger the requirement for additional energy consumption for water treatment to remove the nitrates. While these increasing concentrations of nitrate might pose a human health concern, most water resources were found to be within current maximum contaminant level (MCL) limits of 10 mg L(-1) NO(3)-N. When water resources exceed this MCL, energy-intensive drinking water treatment is required to reduce nitrate levels below 10 mg L(-1). Based on prior estimates of water supplies currently exceeding the nitrate MCL, we calculate that advanced drinking water treatment might require an additional 2360 million kWh annually (for nitrate affected areas only)--a 2100% increase in energy requirements for water treatment in those same areas--to mitigate nitrate contamination and meet the MCL requirement. We predict that projected increases in nitrate contamination in water may impact the energy consumed in the water treatment sector, because of the convergence of several related trends: (1) increasing cornstarch-based ethanol production, (2) increasing nutrient loading in surface water and groundwater resources as a consequence of increased corn-based ethanol production, (3) additional drinking water sources that exceed the MCL for nitrate, and (4) potentially more stringent drinking water standards for nitrate.

Geographical distribution of drinking-water with high iodine level and association between high iodine level in drinking-water and goitre: a Chinese national investigation.

PubMed

Shen, Hongmei; Liu, Shoujun; Sun, Dianjun; Zhang, Shubin; Su, Xiaohui; Shen, Yanfeng; Han, Hepeng

2011-07-01

Excessive iodine intake can cause thyroid function disorders as can be caused by iodine deficiency. There are many people residing in areas with high iodine levels in drinking-water in China. The main aim of the present study was to map the geographical distribution of drinking-water with high iodine level in China and to determine the relationship between high iodine level in drinking-water and goitre prevalence. Iodine in drinking-water was measured in 1978 towns of eleven provinces in China, with a total of 28,857 water samples. We randomly selected children of 8-10 years old, examined the presence of goitre and measured their urinary iodine in 299 towns of nine provinces. Of the 1978 towns studied, 488 had iodine levels between 150 and 300 μg/l in drinking-water, and in 246 towns, the iodine level was >300 μg/l. These towns are mainly distributed along the original Yellow River flood areas, the second largest river in China. Of the 56 751 children examined, goitre prevalence was 6.3 % in the areas with drinking-water iodine levels of 150-300 μg/l and 11.0 % in the areas with drinking-water iodine >300 μg/l. Goitre prevalence increased with water and urinary iodine levels. For children with urinary iodine >1500 μg/l, goitre prevalence was 3.69 times higher than that for those with urinary iodine levels of 100-199 μg/l. The present study suggests that drinking-water with high iodine levels is distributed in eleven provinces of China. Goitre becomes more prevalent with the increase in iodine level in drinking-water. Therefore, it becomes important to prevent goitre through stopping the provision of iodised salt and providing normal drinking-water iodine through pipelines in these areas in China.

Climate change and prairie pothole wetlands: mitigating water-level and hydroperiod effects through upland management

USGS Publications Warehouse

Renton, David A.; Mushet, David M.; DeKeyser, Edward S.

2015-01-01

Prairie pothole wetlands offer crucial habitat for North America’s waterfowl populations. The wetlands also support an abundance of other species and provide ecological services valued by society. The hydrology of prairie pothole wetlands is dependent on atmospheric interactions. Therefore, changes to the region’s climate can have profound effects on wetland hydrology. The relevant literature related to climate change and upland management effects on prairie pothole wetland water levels and hydroperiods was reviewed. Climate change is widely expected to affect water levels and hydroperiods of prairie pothole wetlands, as well as the biota and ecological services that the wetlands support. In general, hydrologic model projections that incorporate future climate change scenarios forecast lower water levels in prairie pothole wetlands and longer periods spent in a dry condition, despite potential increases in precipitation. However, the extreme natural variability in climate and hydrology of prairie pothole wetlands necessitates caution when interpreting model results. Recent changes in weather patterns throughout much of the Prairie Pothole Region have been in increased precipitation that results in increased water inputs to wetlands above losses associated with warmer temperatures. However, observed precipitation increases are within the range of natural climate variability and therefore, may not persist. Identifying management techniques with the potential to affect water inputs to prairie pothole wetlands would provide increased options for managers when dealing with the uncertainties associated with a changing climate. Several grassland management techniques (for example, grazing and burning) have the potential to affect water levels and hydroperiods of prairie pothole by affecting infiltration, evapotranspiration, and snow deposition.

Water-level fluctuations influence sediment porewater ...

EPA Pesticide Factsheets

Reservoirs typically have elevated fish mercury (Hg) levels compared to natural lakes and rivers. A unique feature of reservoirs is water-level management which can result in sediment exposure to the air. The objective of this study is to identify how reservoir water-level fluctuations impact Hg cycling, particularly the formation of the more toxic and bioaccumulative methylmercury (MeHg). Total-Hg (THg), MeHg, stable isotope methylation rates and several ancillary parameters were measured in reservoir sediments (including some in porewater and overlying water) that are seasonally and permanently inundated. The results showed that sediment and porewater MeHg concentrations were over 3-times higher in areas experiencing water-level fluctuations compared to permanently inundated sediments. Analysis of the data suggest that the enhanced breakdown of organic matter in sediments experiencing water-level fluctuations has a two-fold effect on stimulating Hg methylation: 1) it increases the partitioning of inorganic Hg from the solid phase into the porewater phase (lower log Kd values) where it is more bioavailable for methylation; and 2) it increases dissolved organic carbon (DOC) in the porewater which can stimulate the microbial community that can methylate Hg. Sulfate concentrations and cycling were enhanced in the seasonally inundated sediments and may have also contributed to increased MeHg production. Overall, our results suggest that reservoir management a

High temporal resolution modeling of the impact of rain, tides, and sea level rise on water table flooding in the Arch Creek basin, Miami-Dade County Florida USA.

PubMed

Sukop, Michael C; Rogers, Martina; Guannel, Greg; Infanti, Johnna M; Hagemann, Katherine

2018-03-01

Modeling of groundwater levels in a portion of the low-lying coastal Arch Creek basin in northern Miami-Dade County in Southeast Florida USA, which is subject to repetitive flooding, reveals that rain-induced short-term water table rises can be viewed as a primary driver of flooding events under current conditions. Areas below 0.9m North American Vertical Datum (NAVD) elevation are particularly vulnerable and areas below 1.5m NAVD are vulnerable to exceptionally large rainfall events. Long-term water table rise is evident in the groundwater data, and the rate appears to be consistent with local rates of sea level rise. Linear extrapolation of long-term observed groundwater levels to 2060 suggest roughly a doubling of the number of days when groundwater levels exceed 0.9m NAVD and a threefold increase in the number of days when levels exceed 1.5m NAVD. Projected sea level rise of 0.61m by 2060 together with increased rainfall lead to a model prediction of frequent groundwater-related flooding in areas<0.9m NAVD. However, current simulations do not consider the range of rainfall events that have led to water table elevations>1.5m NAVD and widespread flooding of the area in the past. Tidal fluctuations in the water table are predicted to be more pronounced within 600m of a tidally influenced water control structure that is hydrodynamically connected to Biscayne Bay. The inland influence of tidal fluctuations appears to increase with increased sea level, but the principal driver of high groundwater levels under the 2060 scenario conditions remains groundwater recharge due to rainfall events. Copyright © 2017 Elsevier B.V. All rights reserved.

Assessing the influence of water level on schistosomiasis in Dongting Lake region before and after the construction of Three Gorges Dam.

PubMed

Li, Zhongwu; Nie, Xiaodong; Zhang, Yan; Huang, Jinquan; Huang, Bin; Zeng, Guangming

2016-01-01

Schistosomiasis is a severe public health problem in the Dongting Lake region, and its distribution, prevalence, and intensity of infection are particularly sensitive to environmental changes. In this study, the human and bovine schistosomiasis variations in the Dongting Lake region were studied from 1996 to 2010, and the relationships between schistosomiasis and water level were examined. Furthermore, based on these results, the potential effects of the Three Gorges Dam (TGD) on schistosomiasis were investigated. Results showed an increase in human schistosomiasis and in the scope of seriously affected regions, along with a decrease in bovine schistosomiasis. Human schistosomiasis was negatively correlated with water level during wet season (from May to October), particularly the average water level in October. This finding indicated that the decreasing water level may be highly related to the increasing of human schistosomiasis in the Dongting Lake region. Based on this result and the variation of schistosomiasis before and after the construction and operation of TGD, the impoundment of the Three Gorges reservoir is believed to decrease the water level and increase the contact between people and schistosomiasis. Therefore, the TGD, which is operated by regulating water and scheduling water operations, is not good for the control of human schistosomiasis in the Dongting Lake region. Although the extent of the influence of the TGD on schistosomiasis remains unclear, the influence of the TGD on preventing and controlling schistosomiasis should not be ignored.

Hydrologic conditions, groundwater quality, and analysis of sink hole formation in the Albany area of Dougherty County, Georgia, 2009

USGS Publications Warehouse

Gordon, Debbie W.; Painter, Jaime A.; McCranie, John M.

2012-01-01

The U.S. Geological Survey, in cooperation with the Albany Water, Gas, and Light Commission has conducted water resources investigations and monitored groundwater conditions and availability in the Albany, Georgia, area since 1977. This report presents an overview of hydrologic conditions, water quality, and groundwater studies in the Albany area of Dougherty County, Georgia, during 2009. Historical data also are presented for comparison with 2009 data. During 2009, groundwater-level data were collected in 29 wells in the Albany area to monitor water-level trends in the surficial, Upper Floridan, Claiborne, Clayton, and Providence aquifers. Groundwater-level data from 21 of the 29 wells indicated an increasing trend during 2008–09. Five wells show no trend due to lack of data and three wells have decreasing trends. Period-of-record water levels (period of record ranged between 1957–2009 and 2003–2009) declined slightly in 10 wells and increased slightly in 4 wells tapping the Upper Floridan aquifer; declined in 1 well and increased in 2 wells tapping the Claiborne aquifer; declined in 4 wells and increased in 2 wells tapping the Clayton aquifer; and increased in 1 well tapping the Providence aquifer. Analyses of groundwater samples collected during 2009 from 12 wells in the Upper Floridan aquifer in the vicinity of a well field located southwest of Albany indicate that overall concentrations of nitrate plus nitrite as nitrogen increased slightly from 2008 in 8 wells. A maximum concentration of 12.9 milligrams per liter was found in a groundwater sample from a well located upgradient from the well field. The distinct difference in chemical constituents of water samples collected from the Flint River and samples collected from wells located in the well-field area southwest of Albany indicates that little water exchange occurs between the Upper Floridan aquifer and Flint River where the river flows adjacent to, but downgradient of, the well field. Water-quality data collected during 2008 from two municipal wells located in northern Albany and downgradient from a hazardous waste site indicate low-level concentrations of pesticides in one of the wells; however, no pesticides were detected in samples collected during 2009. Detailed geologic cross sections were used to create a three-dimensional, hydrogeologic diagram of the well field southwest of Albany in order to examine the occurrence of subsurface features conducive to sinkhole formation. Monitored groundwater-level data were used to assess the possible relations between sinkhole formation, precipitation, and water levels in the Upper Floridan aquifer. Although the water levels in well 12L382 oscillated above and below the top of the aquifer on a regular basis between 2007 and 2009, sinkhole development did not appear to correlate directly with either well-field pumping or water levels in the Upper Floridan aquifer. Specifically, two sinkholes formed in each of the years 2003 and 2005 when water levels were almost 20 feet above the top of the aquifer during most of the year. Water-level and sinkhole-formation data continue to be collected to allow further study and analysis.

Simulation of effects of ground-water development on water-levels in glacial-drift aquifers in the Brooten-Belgrade area, west-central Minnesota

USGS Publications Warehouse

Delin, G.N.

1991-01-01

The model was used to simulate the steady-state effects of below-normal precipitation (drought) and hypothetical increases in ground-water development. Model results indicate that reduced recharge and increased pumping during a hypothetical 3-year extended drought would lower regional water levels from 2 to 5 feet in each aquifer and as much as 20 feet in the lowermost aquifer zone; ground-water discharge to the East Branch Chippewa and North Fork Crow Rivers would be reduced by 38 percent. The addition of 10 to 20 hypothetical wells in confined aquifers, pumping 123 to 246 million gallons per year, would result in regional water-level declines of 0.1 to 0.5 feet. Simulated water-level declines in wells completed in the lower part of the system would be as much as 5.0 feet as a result of pumping 246 million gallons per year from 20 hypothetical wells. Water-level declines in overlying and underlying aquifers would range from 0.4 to 2.8 feet. Ground-water discharge to the East Branch Chippewa and North Fork Crow Rivers would be unaffected by the pumpage.

How do land use intensity, experimentally increased temperature and water level affect methane and nitrous oxide emissions from a drained fen peatland?

NASA Astrophysics Data System (ADS)

Heinichen, Jan; Eickenscheidt, Tim; Drösler, Matthias

2014-05-01

Rewetting and extensification of peatlands is widely discussed and practiced to reduce losses of CO2 and N2O from drained peat soils. But rewetting is known to carry the risk of increased CH4 emissions. Up to now it is not completely clear how the predicted temperature increase in the face of climate change will alter the N2O and CH4 exchange of grasslands on drained peatland soils in the temperate zone. Therefore we investigated the effects of land use intensity, increased groundwater level, increased temperature and the combination of warming and increased groundwater level on CH4 and N2O exchange of two grassland sites (intensive and extensive grassland) in a drained fen peatland in southern Germany. We set up a factorial design on both land use types, on each three treatments, warming, increased water table level and the combination of warming and increased water table level as well as a control site were established. Temperature was manipulated with open-top chambers (OTCs) and water level manipulation was performed using a pumping system and sheet pile walls. The intensive grassland was cut three times in the year, the extensive grassland once in autumn 2011. Cattle slurry and mineral fertilizer (CAN) were deployed on the intensive grassland. Fluxes of CH4 and N2O were measured biweekly from December 2010 to January 2012 using opaque static closed chambers. The annual mean groundwater level (GWL) of the sites without water level manipulation was -41.5 cm b. g. and -30 cm b. g. at the water level manipulated sites on the intensive grassland. On the extensive grassland the GWL of the sites without water level manipulation was -32 cm b. g. and -21.5 cm b. g. at the water level manipulated sites. Air temperature in 0.2 m was increased in 2011 by 0.7 ° C at the treatments with OTCs on the intensive grassland and by 1.0 ° C at the treatments with OTCs on the extensive grassland respectively. The annual cumulative CH4 exchange ranged from 8.1 ± 3.8 kg C ha-1 yr-1 to 36.3 ± 8.6 kg C ha-1 yr-1on the extensive grassland and from -0.1 ± 0.3 kg C ha-1 yr-1 to 15.0 ± 1.9 kg C ha-1 yr-1 on the intensive grassland. The CH4 emissions of the treatments with increased water level on the intensive grassland were significantly higher compared to the control and warming sites. No significant differences could be observed between CH4 emissions of the treatments on the extensive grassland. However, we found a general significant relationship between CH4 fluxes, groundwater level and temperature. All sites on the intensive grassland show higher annual emissions of N2O compared to the sites on the extensive grassland. The annual cumulative N2O exchange ranged from 3.1 ± 0.5 kg N ha-1 yr-1 to 6.1 ± 0.4 kg N ha-1 yr-1on the intensive grassland and from 0.7 ± 0.1 kg N ha-1 yr-1 to 1.3 ± 0.2 kg N ha-1 yr-1 on the extensive grassland. Significant treatment effects could not be observed for N2O exchange on both land use types.

Correlation analysis of Standardized Precipitation Index (SPI) for the water debit and level of the Cisadane River during El Niño and La Niña years

NASA Astrophysics Data System (ADS)

Khoir, A. N.; Rohmah, M.; Nuryadi

2018-03-01

Hydrometeorological factor causes most disaster in Indonesia, and two of them are drought and flood. This study aims to correlate Standardized Precipitation Index (SPI) 3-monthly to water debit and water level in the Cisadane River. The monthly rainfall data from Serpong and Pasar Baru rain station from 2009 to 2011 when moderate El Niño and moderate La Niña happened. The correlation analysis between debit and water level to SPI 3-monthly used rain post of Serpong to represent the condition of the upstream area and rain post of Pasar Baru to represent the condition of the downstream area. The results showed that during La Niña year, the rainfall on the upstream area of the Cisadane River influenced the increase and the decrease in water debit and water level. Meanwhile, the rainfall on the downstream area of the river has an opposite effect on the increase and the decrease of debit and water level of the Pasar Baru. On the upstream area, the correlation between rainfall and water debit is 0.8, and the correlation between rainfall and water level is also 0.8. During El Niño year, the correlation was less than 0.5.

Running-induced patellofemoral pain fluctuates with changes in patella water content.

PubMed

Ho, Kai-Yu; Hu, Houchun H; Colletti, Patrick M; Powers, Christopher M

2014-01-01

Although increased bone water content resulting from repetitive patellofemoral joint loading has been suggested to be a possible mechanism underlying patellofemoral pain (PFP), there is little data to support this mechanism. The purpose of the current study was to determine whether running results in increases in patella water content and pain and whether 48 hours of rest reduces patella water content and pain to pre-running levels. Ten female runners with a diagnosis of PFP (mean age 25.1 years) participated. Patella water content was quantified using a chemical-shift-encoded water-fat magnetic resonance imaging (MRI) protocol. The visual analog scale (VAS) was used to quantify subjects' pain levels. MRI and pain data were obtained prior to running, immediately following a 40-minute running session, and 48 hours post-running. Pain and patella water content were compared among the 3 time points using one-way ANOVA's with repeated measures. Immediately post-running, persons with PFP reported significant increases in pain and exhibited elevated patella water content. Pain and patella water content decreased to pre-running levels following 48 hours of rest. Our findings suggest that transient changes in patella water content associated with running may, in part, contribute to patellofemoral symptoms.

Nitrate in drinking water and colorectal cancer risk: A nationwide population-based cohort study.

PubMed

Schullehner, Jörg; Hansen, Birgitte; Thygesen, Malene; Pedersen, Carsten B; Sigsgaard, Torben

2018-07-01

Nitrate in drinking water may increase risk of colorectal cancer due to endogenous transformation into carcinogenic N-nitroso compounds. Epidemiological studies are few and often challenged by their limited ability of estimating long-term exposure on a detailed individual level. We exploited population-based health register data, linked in time and space with longitudinal drinking water quality data, on an individual level to study the association between long-term drinking water nitrate exposure and colorectal cancer (CRC) risk. Individual nitrate exposure was calculated for 2.7 million adults based on drinking water quality analyses at public waterworks and private wells between 1978 and 2011. For the main analyses, 1.7 million individuals with highest exposure assessment quality were included. Follow-up started at age 35. We identified 5,944 incident CRC cases during 23 million person-years at risk. We used Cox proportional hazards models to estimate hazard ratios (HRs) of nitrate exposure on the risk of CRC, colon and rectal cancer. Persons exposed to the highest level of drinking water nitrate had an HR of 1.16 (95% CI: 1.08-1.25) for CRC compared with persons exposed to the lowest level. We found statistically significant increased risks at drinking water levels above 3.87 mg/L, well below the current drinking water standard of 50 mg/L. Our results add to the existing evidence suggesting increased CRC risk at drinking water nitrate concentrations below the current drinking water standard. A discussion on the adequacy of the drinking water standard in regards to chronic effects is warranted. © 2018 UICC.

Changes in Blood Lead Levels Associated with Use of Chloramines in Water Treatment Systems

PubMed Central

Miranda, Marie Lynn; Kim, Dohyeong; Hull, Andrew P.; Paul, Christopher J.; Galeano, M. Alicia Overstreet

2007-01-01

Background More municipal water treatment plants are using chloramines as a disinfectant in order to reduce carcinogenic by-products. In some instances, this has coincided with an increase in lead levels in drinking water in those systems. Lead in drinking water can be a significant health risk. Objectives We sought to test the potential effect of switching to chloramines for disinfection in water treatment systems on childhood blood lead levels using data from Wayne County, located in the central Coastal Plain of North Carolina. Methods We constructed a unified geographic information system (GIS) that links blood lead screening data with age of housing, drinking water source, and census data for 7,270 records. The data were analyzed using both exploratory methods and more formal multivariate techniques. Results The analysis indicates that the change to chloramine disinfection may lead to an increase in blood lead levels, the impact of which is progressively mitigated in newer housing. Conclusions Introducing chloramines to reduce carcinogenic by-products may increase exposure to lead in drinking water. Our research provides guidance on adjustments in the local childhood lead poisoning prevention program that should accompany changes in water treatment. As similar research is conducted in other areas, and the underlying environmental chemistry is clarified, water treatment strategies can be optimized across the multiple objectives that municipalities face in providing high quality drinking water to local residents. PMID:17384768

Conceptualization and analysis of ground-water flow system in the Coastal Plain of Virginia and adjacent parts of Maryland and North Carolina

USGS Publications Warehouse

Harsh, John F.; Laczniak, Randell J.

1990-01-01

The ground-water flow system in the Coastal Plain of Virginia and adjacent parts of Maryland and North Carolina consists of a water table aquifer and an underlying sequence of confined aquifers and intervening confining units composed of unconsolidated sand and clay. A digital flow model was developed to enhance knowledge of the behavior of the ground-water flow system in response to its development. Ten pumping periods covering 90 yr of withdrawal simulated the history of ground-water development. Simulated potentiometric-surface maps for 1980 show lowered water levels and the development of coalescing cones of depression around the cities of Franklin, Suffolk, and Williamsburg and the town of West Point, all in Virginia. The largest simulated decline in water level, about 210 ft was near Franklin. Water budgets indicate that over the period of simulation (1891-1980): (1) pumpage from the model area increased by about 105 Mgal/d; (2) lateral boundary outflow increased by about 5 Mgal/d; (3) ground-water flow to streams and coastal water decreased by about 107.5 Mgal/d; (4) lateral boundary inflow increased by about 0.7 Mgal/d, and (5) water released from aquifer storage increased by about 1.6 Mgal/d. Simulated rates of recharge into the confined aquifer system at the end of the final pumping period (1980) varied up to 3.8 in/yr. and simulated rates of discharge out of the confined system varied up to 2.2 in/yr. Results of simulations show an increase of about 110 Mgal/d into the confined system from the unconfined system over the period of simulation. This increase in flow into the confined system affected local discharge of ground water to streams and regional discharge to coastal water. Lowering the storage coefficient of the aquifer had a minimal effect simulated water levels, whereas increasing the storage coefficient had a much more significant effect.

What happens to near-shore habitat when lake and reservoir water levels decline?

EPA Science Inventory

Water management and drought can lead to increased fluctuation and declines in lake and reservoir water levels. These changes can affect near-shore physical habitat and the biotic assemblages that depend upon it. Structural complexity at the land-water interface of lakes promote...

Hydrogeology, water quality, and simulated effects of ground-water withdrawals from the Floridan aquifer system, Seminole County and vicinity, Florida

USGS Publications Warehouse

Spechler, Rick M.; Halford, Keith J.

2001-01-01

The hydrogeology and ground-water quality of Seminole County in east-central Florida was evaluated. A ground-water flow model was developed to simulate the effects of both present day (September 1996 through August 1997) and projected 2020 ground-water withdrawals on the water levels in the surficial aquifer system and the potentiometric surface of the Upper and Lower Floridan aquifers in Seminole County and vicinity. The Floridan aquifer system is the major source of ground water in the study area. In 1965, ground-water withdrawals from the Floridan aquifer system in Seminole County were about 11 million gallons per day. In 1995, withdrawals totaled about 69 million gallons per day. Of the total ground water used in 1995, 74 percent was for public supply, 12 percent for domestic self-supplied, 10 percent for agriculture self-supplied, and 4 percent for recreational irrigation. The principal water-bearing units in Seminole County are the surficial aquifer system and the Floridan aquifer system. The two aquifer systems are separated by the intermediate confining unit, which contains beds of lower permeability sediments that confine the water in the Floridan aquifer system. The Floridan aquifer system has two major water-bearing zones (the Upper Floridan aquifer and the Lower Floridan aquifer), which are separated by a less-permeable semiconfining unit. Upper Floridan aquifer water levels and spring flows have been affected by ground-water development. Long-term hydrographs of four wells tapping the Upper Floridan aquifer show a general downward trend from the early 1950's until 1990. The declines in water levels are caused predominantly by increased pumpage and below average annual rainfall. From 1991 to 1998, water levels rose slightly, a trend that can be explained by an increase in average annual rainfall. Long-term declines in the potentiometric surface varied throughout the area, ranging from about 3 to 12 feet. Decreases in spring discharge also have been observed in a few springs with long-term record. Chloride concentrations in water from the Upper Floridan aquifer in Seminole County range areally from 6.2 to 5,300 milligrams per liter. Chloride concentrations are lowest in the recharge areas of the Floridan aquifer system in the western part of Seminole County and near Geneva. The most highly mineralized water occurs adjacent to the Wekiva River in northwestern Seminole County, around the eastern part of Lake Jesup, and along the St. Johns River in eastern Seminole County. Analysis of limited long-term water-quality data indicates that the chloride concentrations in water for most wells in the Floridan aquifer system in Seminole County have not changed significantly in the 20-year period from 1976 to 1996, and probably not since the mid 1950's. Analysis of water samples collected from some Upper Floridan aquifer springs, however, indicates that the water has become more mineralized during recent years. Increases in specific conductance and concentrations of major cations and anions were observed at several of the springs within the study area where long-term water-quality data were available. Associated with these increases in the mineralization of spring water has been an increase in total nitrate-plus- nitrite as nitrogen concentration. A three-dimensional model was developed to simulate ground-water flow in the surficial and Floridan aquifer systems. The steady-state ground-water flow model was calibrated to water-level data that was averaged over a 1-year period from September 1996 through August 1997. The calibrated flow model generally produced simulated water levels in reasonably close agreement with measured water levels. As a result, the calibrated model was used to simulate the effects of expected increases in ground-water withdrawals on the water levels in the surficial aquifer system and on the potentiometric surface of the Upper and Lower Floridan aquifers in Seminole County. The ca

Nuclear magnetic resonance relaxation characterisation of water status of developing grains of maize (Zea mays L.) grown at different nitrogen levels.

PubMed

Krishnan, Prameela; Chopra, Usha Kiran; Verma, Ajay Pal Singh; Joshi, Devendra Kumar; Chand, Ishwar

2014-04-01

Changes in water status of developing grains of maize (Zea mays L.) grown under different nitrogen levels were characterized by nuclear magnetic resonance (NMR) spectroscopy. There were distinct changes in water status of grains due to the application of different levels of nitrogen (0, 120 and 180 kg N ha(-1)). A comparison of the grain developmental characteristics, composition and physical properties indicated that, not only the developmental characteristics like grain weight, grain number/ear, and rate of grain filling increased, but also bound water characterized by the T2 component of NMR relaxation increased with nitrogen application (50-70%) and developmental stages leading to maturation (10-60%). The consistency in the patterns of responses to free water and intermediate water to increasing levels of nitrogen application and grain maturity suggested that nitrogen application resulted in more proportion of water to both bound- and intermediate states and less in free state. These changes are further corroborated by the concomitant increases in protein and starch contents in grains from higher nitrogen treatments as macromolecules like protein and starch retain more amount of water in the bound state. The results of the changes in T2 showed that water status during grain development was not only affected by developmental processes but also by nitrogen supply to plants. This study strongly indicated a clear nutrient and developmental stage dependence of grain tissue water status in maize. Copyright © 2013 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Water Quality and Hydrology of Silver Lake, Barron County, Wisconsin, With Special Emphasis on Responses of a Terminal Lake to Changes in Phosphorus Loading and Water Level

USGS Publications Warehouse

Robertson, Dale M.; Rose, William J.; Fitzpatrick, Faith A.

2009-01-01

Silver Lake is typically an oligotrophic-to-mesotrophic, soft-water, terminal lake in northwestern Wisconsin. A terminal lake is a closed-basin lake with surface-water inflows but no surface-water outflows to other water bodies. After several years with above-normal precipitation, very high water levels caused flooding of several buildings near the lake and erosion of soil around much of the shoreline, which has been associated with a degradation in water quality (increased phosphorus and chlorophyll a concentrations and decreased water clarity). To gain a better understanding of what caused the very high water levels and degradation in water quality and collect information to better understand the lake and protect it from future degradation, the U.S. Geological Survey did a detailed study from 2004 to 2008. This report describes results of the study; specifically, lake-water quality, historical changes in water level, water and phosphorus budgets for the two years monitored in the study, results of model simulations that demonstrate how changes in phosphorus inputs affect lake-water quality, and the relative importance of changes in hydrology and changes in the watershed to the water quality of the lake. From 1987 to about 1996, water quality in Silver Lake was relatively stable. Since 1996, however, summer average total phosphorus concentrations increased from about 0.008 milligrams per liter (mg/L) to 0.018 mg/L in 2003, before decreasing to 0.011 mg/L in 2008. From 1996 to 2003, Secchi depths decreased from about 14 to 7.4 feet, before increasing to about 19 feet in 2008. Therefore, Silver Lake is typically classified as oligotrophic to mesotrophic; however, during 2002-4, the lake was classified as mesotrophic to eutrophic. Because productivity in Silver Lake is limited by phosphorus, phosphorus budgets for the lake were constructed for monitoring years 2005 and 2006. The average annual input of phosphorus was 216 pounds: 78 percent from tributary and nearshore runoff and 22 percent from atmospheric deposition. Because Silver Lake is hydraulically mounded above the local groundwater system, little or no input of phosphorus to the lake is from groundwater and septic systems. Silver Lake had previously been incorrectly described as a groundwater flowthrough lake. Phosphorus budgets were constructed for a series of dry years (low water levels) and a series of wet years (high water levels). About 6 times more phosphorus was input to the lake during wet years with high water levels than during the dry years. Phosphorus from erosion represented 13-20 percent of the phosphorus input during years with very high water levels. Results from the Canfield and Bachman eutrophication model and Carlson trophic state index equations demonstrated that water quality in Silver Lake directly responds to changes in external phosphorus input, with the percent change in chlorophyll a being about 80 percent of the percent change in total phosphorus input and the change in Secchi depth and total phosphorus concentrations being about 40 and 50 percent of the percent change in input, respectively. Therefore, changes in phosphorus input should impact water quality. Specific scenarios were simulated with the models to describe the effects of natural (climate-driven) and anthropogenic (human-induced) changes. Results of these scenarios demonstrated that several years of above-normal precipitation cause sustained high water levels and a degradation in water quality, part of which is due to erosion of the shoreline. Results also demonstrated that 1) changes in tributary and nearshore runoff have a dramatic effect on lake-water quality, 2) diverting water into the lake to increase the water level is expected to degrade the water quality, and 3) removal of water to decrease the water level of the lake is expected to have little effect on water quality. Fluctuations in water levels since 1967, when records began for the lake, are representative

Exposure to high-fluoride drinking water and risk of dental caries and dental fluorosis in Haryana, India.

PubMed

Marya, Charu Mohan; Ashokkumar, B R; Dhingra, Sonal; Dahiya, Vandana; Gupta, Anil

2014-05-01

The present study aimed to determine the prevalence of and relationship between dental caries and dental fluorosis at varying levels of fluoride in drinking water. The study was conducted among 3007 school children in the age group of 12 to 16 years in 2 districts of Haryana having varying fluoride levels in drinking water. Type III examination for dental caries according to the WHO index and dental fluorosis estimation according to Dean's index was done. The prevalence of dental caries decreased from 48.02% to 28.07% as fluoride levels increased from 0.5 to 1.13 ppm, but as the fluoride level increased further to 1.51 ppm, there was no further reduction in caries prevalence, but there was a substantial increase in fluorosis prevalence. The optimum level of fluoride in drinking water was found to be 1.13 ppm, at which there was maximum caries reduction with minimum amount of esthetically objectionable fluorosis. © 2012 APJPH.

Water-Level Data for the Albuquerque Basin and Adjacent Areas, Central New Mexico, Period of Record Through September 30, 2006

USGS Publications Warehouse

Beman, Joseph E.

2007-01-01

The Albuquerque Basin, located in central New Mexico, is about 100 miles long and 25 to 40 miles wide. The basin is defined as the extent of consolidated and unconsolidated deposits of Tertiary and Quaternary age that encompass the structural Rio Grande Rift within the basin. Drinking-water supplies throughout the basin are currently (2007) obtained solely from ground-water resources. An increase of about 20 percent in the population from 1990 to 2000 also resulted in an increased demand for water. From April 1982 through September 1983, a network of wells was established to monitor changes in ground-water levels throughout the basin. This network consisted of 6 wells with analog-to-digital recorders and 27 wells where water levels were measured monthly. Currently (2007), the network consists of 133 wells and piezometers. This report presents water-level data collected by U.S. Geological Survey personnel at 133 sites through 2007.

Organ-coordinated response of early post-germination mahogany seedlings to drought.

PubMed

Horta, Lívia P; Braga, Márcia R; Lemos-Filho, José P; Modolo, Luzia V

2014-04-01

Water deficit tolerance during post-germination stages is critical for seedling recruitment. In this work, we studied the effect of water deficit on morphological and biochemical responses in different organs of newly germinated mahogany (Swietenia macrophylla King) seedlings, a woody species that occurs in the Amazon rainforest. The root : shoot ratio increased under water deficit. The leaf number and water potential were not altered, although reductions in leaf area and stomatal conductance were observed. Osmotic potential became more negative in leaves of seedlings under severe stress. Water deficit increased fructose, glucose, sucrose and myo-inositol levels in leaves. Stems accumulated fructose, glucose and l-proline. Nitric oxide (NO) levels increased in the vascular cylinder of roots under severe stress while superoxide anion levels decreased due to augmented superoxide dismutase activity in this organ. Water deficit induced glutathione reductase activity in both roots and stems. Upon moderate or severe stress, catalase activity decreased in leaves and remained unaffected in the other seedling organs, allowing for an increase of hydrogen peroxide (H2O2) levels in leaves. Overall, the increase of signaling molecules in distinct organs-NO in roots, l-proline in stems and H2O2 and myo-inositol in leaves-contributed to the response of mahogany seedlings to water deficit by triggering biochemical processes that resulted in the attenuation of oxidative stress and the establishment of osmotic adjustment. Therefore, this body of evidence reveals that the development of newly germinated mahogany seedlings may occur in both natural habitats and crop fields even when water availability is greatly limited.

Barrier island response to an elevated sea-level anomaly: Onslow Beach, North Carolina, USA

NASA Astrophysics Data System (ADS)

Theuerkauf, E. J.; Rodriguez, A. B.; Fegley, S. R.; Luettich, R.

2012-12-01

Variations in sea level over time scales ranging from hours to millennia influence coastal processes and evolution. At annual time scales, elevated sea-level anomalies produce coastal flooding and promote beach erosion. This study examines the coastal response of Onslow Beach, North Carolina to the summer 2009 East Coast sea-level anomaly. Onslow Beach is a 12-km-long wave-dominated barrier island with highly variable along-barrier morphology. The transgressive southern portion of the island is characterized by a narrow beach, low dunes, and multiple washover fans, while the regressive northern portion is characterized by a wide beach and continuous tall dunes. Hourly tide gauge data from adjacent NOAA stations (Beaufort and Wrightsville Beach) are used to determine the timing and extent of elevated water levels. The seasonal and longer term trends (relative sea level rise) are removed from both of the water level series and the sea-level anomaly is represented by a large residual between the observed and predicted water levels. Beach response is quantified using terrestrial laser scanning for morphology and from geoprobe cores to determine the maximum depth of erosion (MDOE). The mean high water (MHW) shoreline and dune toe are digitized from digital elevation models derived from the laser scans and analyzed using the Digital Shoreline Analysis System (DSAS). Landward (negative) movement of these contacts indicates erosion. Wave data collected from an Acoustic Wave and Current Meter (AWAC) located offshore of the southern end of Onslow Beach is used to characterize the wave regime throughout the study. Water level is elevated in the tide gauge data from June 2009 to March 2010. This sea-level anomaly corresponds with an increase in the maximum depth of erosion between 2009 and 2010. Landward movement of the MHW shoreline and the dunetoe increased during the period between September 2009 and May 2010 indicating an increase in beach erosion during the sea-level anomaly. No significant increase in wave height was observed during this period, suggesting that the increase in beach erosion resulted from the sea-level anomaly. The sites that were strongly impacted by the sea-level anomaly did not fully recover from the beach erosion and consequently experienced large amounts of erosion in response to Hurricane Irene in 2011. These results suggest that long duration (weeks to months) high water levels cause changes to the beach similar to those generally thought to occur only during large storms. Dune erosion from higher sea levels weakens a beaches defense to storms, leading to increased beach erosion and overwash if a storm occurs before the beach can recover. It is likely that similar high water events will increase in duration and magnitude with future climate change, leading to increased "fair-weather" beach erosion and priming the system for devastating hurricane impacts.

Assessment of salinity intrusion in the James and Chickahominy Rivers as a result of simulated sea-level rise in Chesapeake Bay, East Coast, USA.

PubMed

Rice, Karen C; Hong, Bo; Shen, Jian

2012-11-30

Global sea level is rising, and the relative rate in the Chesapeake Bay region of the East Coast of the United States is greater than the worldwide rate. Sea-level rise can cause saline water to migrate upstream in estuaries and rivers, threatening freshwater habitat and drinking-water supplies. The effects of future sea-level rise on two tributaries of Chesapeake Bay, the James and Chickahominy (CHK) Rivers, were evaluated in order to quantify the salinity change with respect to the magnitude of sea-level rise. Such changes are critical to: 1) local floral and faunal habitats that have limited tolerance ranges to salinity; and 2) a drinking-water supply for the City of Newport News, Virginia. By using the three-dimensional Hydrodynamic-Eutrophication Model (HEM-3D), sea-level rise scenarios of 30, 50, and 100 cm, based on the U.S. Climate Change Science Program for the mid-Atlantic region for the 21st century, were evaluated. The model results indicate that salinity increases in the entire river as sea level rises and that the salinity increase in a dry year is greater than that in a typical year. In the James River, the salinity increase in the middle-to-upper river (from 25 to 50 km upstream of the mouth) is larger than that in the lower and upper parts of the river. The maximum mean salinity increase would be 2 and 4 ppt for a sea-level rise of 50 and 100 cm, respectively. The upstream movement of the 10 ppt isohaline is much larger than the 5 and 20 ppt isohalines. The volume of water with salinity between 10 and 20 ppt would increase greatly if sea level rises 100 cm. In the CHK River, with a sea-level rise of 100 cm, the mean salinity at the drinking-water intake 34 km upstream of the mouth would be about 3 ppt in a typical year and greater than 5 ppt in a dry year, both far in excess of the U.S. Environmental Protection Agency's secondary standard for total dissolved solids for drinking water. At the drinking-water intake, the number of days of salinity greater than 0.1 ppt increases with increasing sea-level rise; during a dry year, 0.1 ppt would be exceeded for more than 100 days with as small a rise as 30 cm. Copyright © 2012 Elsevier Ltd. All rights reserved.

Assessment of salinity intrusion in the James and Chickahominy Rivers as a result of simulated sea-level rise in Chesapeake Bay, East Coast, USA

USGS Publications Warehouse

Rice, Karen; Bo Hong,; Jian Shen,

2012-01-01

Global sea level is rising, and the relative rate in the Chesapeake Bay region of the East Coast of the United States is greater than the worldwide rate. Sea-level rise can cause saline water to migrate upstream in estuaries and rivers, threatening freshwater habitat and drinking-water supplies. The effects of future sea-level rise on two tributaries of Chesapeake Bay, the James and Chickahominy (CHK) Rivers, were evaluated in order to quantify the salinity change with respect to the magnitude of sea-level rise. Such changes are critical to: 1) local floral and faunal habitats that have limited tolerance ranges to salinity; and 2) a drinking-water supply for the City of Newport News, Virginia. By using the three-dimensional Hydrodynamic-Eutrophication Model (HEM-3D), sea-level rise scenarios of 30, 50, and 100 cm, based on the U.S. Climate Change Science Program for the mid-Atlantic region for the 21st century, were evaluated. The model results indicate that salinity increases in the entire river as sea level rises and that the salinity increase in a dry year is greater than that in a typical year. In the James River, the salinity increase in the middle-to-upper river (from 25 to 50 km upstream of the mouth) is larger than that in the lower and upper parts of the river. The maximum mean salinity increase would be 2 and 4 ppt for a sea-level rise of 50 and 100 cm, respectively. The upstream movement of the 10 ppt isohaline is much larger than the 5 and 20 ppt isohalines. The volume of water with salinity between 10 and 20 ppt would increase greatly if sea level rises 100 cm. In the CHK River, with a sea-level rise of 100 cm, the mean salinity at the drinking-water intake 34 km upstream of the mouth would be about 3 ppt in a typical year and greater than 5 ppt in a dry year, both far in excess of the U.S. Environmental Protection Agency's secondary standard for total dissolved solids for drinking water. At the drinking-water intake, the number of days of salinity greater than 0.1 ppt increases with increasing sea-level rise; during a dry year, 0.1 ppt would be exceeded for more than 100 days with as small a rise as 30 cm.

Rising ground-water level in downtown Louisville, Kentucky, 1972-1977

USGS Publications Warehouse

Kernodle, J.M.; Whitesides, D.V.

1977-01-01

Ground-water levels in the alluvial aquifer in Louisville, Jefferson County, Kentucky, are rising at a rate which could cause wet basements and possible structural damage tc buildings in the downtown area by 1982. The predicted water level for 1982 is based on the nearly linear increase which has been observed from 1972 to 1977, during which period a rise of as much as 32 feet was recorded in water-level observation wells. Foremost among the possible causes of the rise is a decrease in withdrawal of ground water.

Water-level fluctuation in wetlands as a function of landscape condition in the prairie pothole region

USGS Publications Warehouse

Euliss, Ned H.; Mushet, David M.

1996-01-01

We evaluated water-level fluctuation (maximum water depth - minimum water depth/catchment size) in 12 temporary, 12 seasonal, and 12 semipermanent wetlands equally distributed among landscapes dominated by tilled agricultural lands and landscapes dominated by grassland. Water levels fluctuated an average of 14.14 cm in wetlands within tilled agricultural landscapes, while water levels in wetlands within grassland landscapes fluctuated an average of only 4.27 cm. Tillage reduces the natural capacity of catch meets to mitigate surface flow into wetland basins during precipitation events, resulting in greater water-level fluctuations in wetlands with tilled catchments. In addition, water levels in temporary and seasonal wetlands fluctuated an average of 13.74 cm and 11.82 cm, respectively, while water levels in semipermanent wetlands fluctuated only 2.77 cm. Semipermanent wetlands receive a larger proportion of their water as input from ground water than do either temporary or seasonal wetlands. This input of water from the ground has a stabilizing effect on water-levels of semipermanent wetlands. Increases in water-level fluctuation due to tillage or due to alteration of ground-water hydrology may ultimately affect the composition of a wetland's flora and fauna. In this paper, we also describe an inexpensive device for determining absolute maximum and minimum water levels in wetlands.

Numerical modeling of the impact of sea-level rise on fringing coral reef hydrodynamics and sediment transport

USGS Publications Warehouse

Storlazzi, C.D.; Elias, E.; Field, M.E.; Presto, M.K.

2011-01-01

Most climate projections suggest that sea level may rise on the order of 0.5-1.0 m by 2100; it is not clear, however, how fluid flow and sediment dynamics on exposed fringing reefs might change in response to this rapid sea-level rise. Coupled hydrodynamic and sediment-transport numerical modeling is consistent with recent published results that suggest that an increase in water depth on the order of 0.5-1.0 m on a 1-2 m deep exposed fringing reef flat would result in larger significant wave heights and setup, further elevating water depths on the reef flat. Larger waves would generate higher near-bed shear stresses, which, in turn, would result in an increase in both the size and the quantity of sediment that can be resuspended from the seabed or eroded from adjacent coastal plain deposits. Greater wave- and wind-driven currents would develop with increasing water depth, increasing the alongshore and offshore flux of water and sediment from the inner reef flat to the outer reef flat and fore reef where coral growth is typically greatest. Sediment residence time on the fringing reef flat was modeled to decrease exponentially with increasing sea-level rise as the magnitude of sea-level rise approached the mean water depth over the reef flat. The model results presented here suggest that a 0.5-1.0 m rise in sea level will likely increase coastal erosion, mixing and circulation, the amount of sediment resuspended, and the duration of high turbidity on exposed reef flats, resulting in decreased light availability for photosynthesis, increased sediment-induced stress on the reef ecosystem, and potentially affecting a number of other ecological processes.

[Interactive impact of water and nitrogen on yield, quality of watermelon and use of water and nitrogen in gravel-mulched field].

PubMed

Du, Shao-ping; Ma, Zhong-ming; Xue, Liang

2015-12-01

In order to develop the optimal coupling model of water and nitrogen of watermelon under limited irrigation in gravel-mulched field, a field experiment with split-plot design was conducted to study the effects of supplementary irrigation volume, nitrogen fertilization, and their interactions on the growth, yield, quality and water and nitrogen use efficiency of watermelon with 4 supplementary irrigation levels (W: 0, 35, 70, and 105 m³ · hm⁻²) in main plots and 3 nitrogen fertilization levels (N: 0, 120, and 200 kg N · hm⁻²) in sub-plots. The results showed that the photosynthetic rate, yield, and water and nitrogen use efficiency of watermelon increased with the increasing supplementary irrigation, but the nitrogen partial productivity and nitrogen use efficiency decreased with increasing nitrogen fertilization level. The photosynthetic rate and quality indicators increased with increasing nitrogen fertilization level as the nitrogen rate changed from 0 to 120 kg N · hm⁻², but no further significant increase as the nitrogen rate exceeded 120 kg · hm⁻². The interactive effects between water and nitrogen was significant for yield and water and nitrogen use efficiency of watermelon, supplementary irrigation volume was a key factor for the increase yield compared with the nitrogen fertilizer, and the yield reached the highest for the W₇₀N₂₀₀ and W₁₀₅ N₁₂₀ treatments, for which the yield increased by 42.4% and 40.4% compared to CK. Water use efficiency (WUE) was improved by supplementary irrigation and nitrogen rate, the WUE of all nitrogen fertilizer treatments were more than 26 kg · m⁻³ under supplemental irrigation levels 70 m³ · hm⁻² and 105 m³ · hm⁻². The nitrogen partial productivity and nitrogen use efficiency reached the highest in the treatment of W₁₀₅N₁₂₀. It was considered that under the experimental condition, 105 m³ · hm⁻² of supplementary irrigation plus 120 kg · hm⁻² of nitrogen fertilization was the optimal combination of obtaining the high yield and high efficiency.

Hydrological Changes Induced by Distant Earthquakes at the Lujiang Well in Anhui, China

NASA Astrophysics Data System (ADS)

Ma, Yuchuan; Wang, Guangcai; Tao, Yuechao

2017-10-01

The Lujiang well, a 63 °C artesian well, recorded sustained hydrological changes following the 1999 Chi-Chi M w 7.6, the 2008 Wenchuan M w 7.9, and the 2011 Tohoku M w 9.0 earthquakes, including rises in the water radon concentration, water pressure, discharge and water level, and drops in the water temperature. These hydrological changes are synchronous and have similar amplitudes. The permeability inferred through the tidal response of water level showed insignificant change after the three earthquakes. We attribute the observed hydrological changes to the increase in the vertical recharge on the basis that the water radon concentration of the Lujiang well increased following the increase of recharge to the well; significant vertical flow exists in the well-aquifer system; the well has a lower water radon concentration and a higher water temperature than its adjacent wells with different aquifers.

Prevalence of dental fluorosis in relation with different fluoride levels in drinking water among school going children in Sarada tehsil of Udaipur district, Rajasthan.

PubMed

Sarvaiya, B U; Bhayya, D; Arora, R; Mehta, D N

2012-01-01

To estimate the prevalence of dental fluorosis in relation with different fluoride levels in drinking water among school going children of 6-12 years age group. Dental fluorosis was recorded using Dean's index in school children of selected villages. The drinking water samples of all the selected villages were collected in polyethylene bottles and the fluoride content of these samples was determined by fluoride ion selective method using Orion microprocessor analyser. The overall prevalence of dental fluorosis was found to be 69.84%. An increase in the community fluorosis index (CFI) with corresponding increase in water fluoride content was found. There was an increase in prevalence of dental fluorosis with a corresponding increase in water fluoride content from 0.8 ppm to 4.1 ppm. A significantly strong positive correlation was found between CFI and fluoride concentration in drinking water.

Analysis of ground-water flow in the Catahoula aquifer system in the vicinity of Laurel and Hattiesburg, Mississippi

USGS Publications Warehouse

Halford, K.J.; Barber, N.L.

1995-01-01

The upper, middle, and lower Catahoula aquifers in the vicinity of the cites of Laurel and Hattiesburg in southern Mississippi are made up of irregular, discontinuous sand zones in the Catahoula Formation of Miocene age. In places thee three aquifers may be hydraulically well connected, and are referred to as the Catahoula aquifer system. Withdrawal from the Catahoula aquifers increased from 28 million gallons per day (Mgal/d) to 41 Mgal/d during 1970 to 1985, and decreased to 38 Mgal/d during 1990. Most withdrawal in the Laurel area is from the lower and middle Catahoula, and most withdrawal in the Hattiesburg area is from the middle and upper Catahoula aquifers. In the Laurel area, water levels in selected wells in the lower Catahoula aquifer declined at rates ranging from about 1 to 3.6 feet/ year until the late 1980's in response to the increase in pumping. A three-dimensional model was developed to represent ground-water flow in the Catahoula aquifers. Simulated water levels in the lower Catahoula aquifer, the layer most affected by pumping, were lowered from predevelopment levels as much as 130 feet in the Laurel area and 100 feet in the Hattiesburg area, according to the model analysis of 1992 conditions. Three scenarios of increased pumpage, for the period 1992-2020, were simulated. Under the low-growth scenario, water- level declines would be 20 feet or less below 1992 water levels in the middle and upper Catahoula aquifer in the Hattiesburg area, and about 60 feet in the lower Catahoula aquifer in the Laurel area. Under the moderate-growth scenario, water-level declines would be 40 feet or less below 1992 water levels in the middle Catahoula aquifer in the Hattiesburg area. Water-level declines would be about 110 feet in the lower Catahoula aquifer in the Laurel area, and water levels would approach the top of the aquifer. Under the high-growth scenario, water-level declines would be 40 feet or less in the upper Catahoula aquifer and about 80 feet in the middle Catahoula, with the largest declines occurring in the Hattiesburg area. Water levels would decline about 130 feet and would be drawn down below the top of the lower Catahoula aquifer in the Laurel area under the high-growth scenario.

Analysis of Compound Water Hazard in Coastal Urbanized Areas under the Future Climate

NASA Astrophysics Data System (ADS)

Shibuo, Y.; Taniguchi, K.; Sanuki, H.; Yoshimura, K.; Lee, S.; Tajima, Y.; Koike, T.; Furumai, H.; Sato, S.

2017-12-01

Several studies indicate the increased frequency and magnitude of heavy rainfalls as well as the sea level rise under the future climate, which implies that coastal low-lying urbanized areas may experience increased risk against flooding. In such areas, where river discharge, tidal fluctuation, and city drainage networks altogether influence urban inundation, it is necessary to consider their potential interference to understand the effect of compound water hazard. For instance, pump stations cannot pump out storm water when the river water level is high, and in the meantime the river water level shall increase when it receives pumped water from cities. At the further downstream, as the tidal fluctuation regulates the water levels in the river, it will also affect the functionality of pump stations and possible inundation from rivers. In this study, we estimate compound water hazard in the coastal low-lying urbanized areas of the Tsurumi river basin under the future climate. We developed the seamlessly integrated river, sewerage, and coastal hydraulic model that can simulate river water levels, water flow in sewerage network, and inundation from the rivers and/or the coast to address the potential interference issue. As a forcing, the pseudo global warming method, which applies the changes in GCM anomaly to re-analysis data, is employed to produce ensemble typhoons to drive the seamlessly integrated model. The results show that heavy rainfalls caused by the observed typhoon generally become stronger under the pseudo global climate condition. It also suggests that the coastal low-lying areas become extensively inundated if the onset of river flooding and storm surge coincides.

Apelin-13 increased food intake with serum ghrelin and leptin levels in male rats.

PubMed

Saral, S; Alkanat, M; Sumer, A; Canpolat, S

2018-01-01

In this study, we aimed to explain the role of apelin-13 on body weight, food and water intake with serum leptin, ghrelin, neuropeptid Y (NPY) and peptid YY (PYY) levels in male rat. Thirty-two Sprague-Dawley male rats were used for the study. The rats were injected SP (0.9 %) intraperitoneally (i.p) in the control group and 30 (AP30), 100 (AP100) and 300 (AP300) µg/kg apelin-13 in the study groups, respectively, 10 min before the transition to dark period, for 10 days. During the experimental period, with light and dark periods of food and water intake, body weights were recorded in rats. Rats were euthanized and serum samples were obtained. In serum samples leptin, ghrelin, NPY and PYY levels were measured with specific ELISA kit. Apelin-13 was increased body weights in all three (AP30, AP100 and AP300) groups compared with the control group. AP100 and AP300 groups had increased food intake in the dark and the cumulative period, but in the light period food intake values were not significantly increased (p > 0.05). As for the value of water intake, compared with the control group, all dose of apelin-13 increased water intake during the dark and the cumulative period. There was no significant change in water intake in the light period. On the other hand, compared with the control group, serum leptin levels were found to increase in the groups administered 100 and 300 µg/kg of apelin-13 (p < 0.05). Ghrelin levels were found high in all groups treated with apelin-13. Serum levels of NPY decreased only in the 300 µg/kg apelin-13 treated group (p 0.05). Apelin-13 increases body weight in rats as well as food and water intake (dark and cumulative period). Additionally, ghrelin can mediate the orexigenic effect of apelin-13 in the regulation of food intake (Fig. 4, Ref. 37).

The impact of dietary protein levels on nutrient digestibility and water and nitrogen balances in eventing horses.

PubMed

Oliveira, C A A; Azevedo, J F; Martins, J A; Barreto, M P; Silva, V P; Julliand, V; Almeida, F Q

2015-01-01

This study was performed to evaluate the impact of dietary protein levels on nutrient digestibility and water and nitrogen balances in conditioning eventing horses. Twenty-four Brazilian Sport Horses, male and female (8.0 to 15.0 yr; 488 ± 32 kg BW), were used in a randomized design with 4 levels of CP diets: 7.5%, 9.0%, 11.0%, and 13.0%. A digestion assay was performed with partial feces collection over 4 d, followed by 1 d of total urine collection. Data were submitted to regression analysis and adjusted to linear and quadratic models (P < 0.05). No differences were observed in the intake of DM, OM, EE, ADF, and NDF as a function of dietary protein levels. Dry matter intake average was 1.7% of BW. CP and N intake showed a linear increase as a function of increasing protein level in diets. A quadratic response (P < 0.05) was observed on the CP and NDF digestibility coefficients, with the maximum estimated level of digestibility at 11.6% and 11.4% CP in the diet, respectively. There was a linear effect on ADF digestibility coefficients, digestible DM and protein intake, and CP/DE ratio according to dietary protein levels. There was no impact of dietary protein levels on daily water intake, total water intake, or fecal water excretion. Urinary excretion values showed a linear increase in response to increased dietary protein levels, but no impact was observed on water balance, with an average of 8.4 L/d. Nitrogen intake (NI), N absorption (NA), and urinary N increased linearly as a function of increasing dietary protein levels. There was no impact of dietary protein levels on N retention (NR), with an average of 7.5 g N/d. Nitrogen retention as a percentage of NI or NA showed no significant changes in the function of dietary protein levels. There was an impact of dietary protein levels on the digestibility coefficient of CP, NDF, ADF, and digestible protein intake on conditioning eventing horses. The 11.6% CP level in the diet provided an intake of 2.25 g CP/kg BW and 0.37 g N/kg BW, and this intake was the most appropriate for the conditioning of intensely exercised horses, considering the responses related to NI, NA, and the estimated NR to NA ratio. The NDF and ADF responses indicated that dietary fiber was more digested with an increased amount of N in the digestive tract.

Remote sensing based crop type mapping and evapotranspiration estimates at the farm level in arid regions of the globe

NASA Astrophysics Data System (ADS)

Ozdogan, M.; Serrat-Capdevila, A.; Anderson, M. C.

2017-12-01

Despite increasing scarcity of freshwater resources, there is dearth of spatially explicit information on irrigation water consumption through evapotranspiration, particularly in semi-arid and arid geographies. Remote sensing, either alone or in combination with ground surveys, is increasingly being used for irrigation water management by quantifying evaporative losses at the farm level. Increased availability of observations, sophisticated algorithms, and access to cloud-based computing is also helping this effort. This presentation will focus on crop-specific evapotranspiration estimates at the farm level derived from remote sensing in a number of water-scarce regions of the world. The work is part of a larger effort to quantify irrigation water use and improve use efficiencies associated with several World Bank projects. Examples will be drawn from India, where groundwater based irrigation withdrawals are monitored with the help of crop type mapping and evapotranspiration estimates from remote sensing. Another example will be provided from a northern irrigation district in Mexico, where remote sensing is used for detailed water accounting at the farm level. These locations exemplify the success stories in irrigation water management with the help of remote sensing with the hope that spatially disaggregated information on evapotranspiration can be used as inputs for various water management decisions as well as for better water allocation strategies in many other water scarce regions.

Predicting Trihalomethanes (THMs) in the New York City Water Supply

NASA Astrophysics Data System (ADS)

Mukundan, R.; Van Dreason, R.

2013-12-01

Chlorine, a commonly used disinfectant in most water supply systems, can combine with organic carbon to form disinfectant byproducts including carcinogenic trihalomethanes (THMs). We used water quality data from 24 monitoring sites within the New York City (NYC) water supply distribution system, measured between January 2009 and April 2012, to develop site-specific empirical models for predicting total trihalomethane (TTHM) levels. Terms in the model included various combinations of the following water quality parameters: total organic carbon, pH, specific conductivity, and water temperature. Reasonable estimates of TTHM levels were achieved with overall R2 of about 0.87 and predicted values within 5 μg/L of measured values. The relative importance of factors affecting TTHM formation was estimated by ranking the model regression coefficients. Site-specific models showed improved model performance statistics compared to a single model for the entire system most likely because the single model did not consider locational differences in the water treatment process. Although never out of compliance in 2011, the TTHM levels in the water supply increased following tropical storms Irene and Lee with 45% of the samples exceeding the 80 μg/L Maximum Contaminant Level (MCL) in October and November. This increase was explained by changes in water quality parameters, particularly by the increase in total organic carbon concentration and pH during this period.

Water-level data for the Albuquerque Basin and adjacent areas, central New Mexico, period of record through September 30, 2010

USGS Publications Warehouse

Beman, Joseph E.

2011-01-01

The Albuquerque Basin, located in central New Mexico, is about 100 miles long and 25-40 miles wide. The basin is defined as the extent of consolidated and unconsolidated deposits of Tertiary and Quaternary age that encompasses the structural Rio Grande Rift within the basin. Drinking-water supplies throughout the basin were obtained solely from groundwater resources until December 2008, when surface water from the Rio Grande began being treated and integrated into the system. An increase of about 20 percent in the basin human population from 1990 to 2000 and about a 22 percent increase from 2000 to 2010 also resulted in an increased demand for water. A network of wells was established by the U.S. Geological Survey in cooperation with the City of Albuquerque to monitor changes in groundwater levels throughout the basin from April 1982 through September 1983. This network consisted of 6 wells with analog-to-digital recorders and 27 wells where water levels were measured monthly in 1983. Currently (2010), the network consists of 124 wells and piezometers (a piezometer is a small-diameter subwell usually nested within a larger well). To better help the Albuquerque Bernalillo County Water Utility Authority manage water use, this report presents water-level data collected by U.S. Geological Survey personnel at those 124 sites through water year 2010.

Estimating Potential Increased Bladder Cancer Risk Due to Increased Bromide Concentrations in Sources of Disinfected Drinking Waters

EPA Science Inventory

Public water systems are increasingly facing higher bromide levels in their source waters from anthropogenic contamination through coal-fired power plants, conventional oil and gas extraction, and hydraulic fracturing. Climate change is likely to exacerbate this in coming years. ...

Estimating Potential Increased Bladder Cancer Risk Due to Increased Bromide Concentrations in Sources of Disinfected Drinking Waters - slides

EPA Science Inventory

Public water systems are increasingly facing higher bromide levels in their source waters from anthropogenic contamination through coal-fired powerplants, conventional oil and gas extraction, and hydraulic fracturing. Climate change is likely to exacerbate this in coming years. W...

Calcium in drinking water: effect on iron stores in Danish blood donors-results from the Danish Blood Donor Study.

PubMed

Rigas, Andreas S; Ejsing, Benedikte H; Sørensen, Erik; Pedersen, Ole B; Hjalgrim, Henrik; Erikstrup, Christian; Ullum, Henrik

2018-06-01

Studies confirm that calcium inhibits iron absorption. Danish tap water comes from groundwater, which contains varying amounts of calcium depending on the subsoil. We investigated the association of calcium in drinking water with iron levels in Danish blood donors. We used data on Danish blood donors including dietary and lifestyle habits, blood donation history, and physiologic characteristics including measures of ferritin levels along with information on area of residence from The Danish Blood Donor Study. Data on calcium levels in groundwater ("water hardness") were obtained through the Geological Survey of Denmark and Greenland. We performed multiple linear and logistic regression analyses to evaluate the effect of water hardness on ferritin levels and risk of having iron deficiency (defined as ferritin levels <15 ng/mL), stratified by sex. There was a significant negative association between water hardness and ferritin levels in both men and women. Risk of iron deficiency was correspondingly increased in both men (odds ratio [OR], 1.55; 95% confidence interval [CI], 1.14-2.12) and women (OR, 1.20; 95% CI, 1.03-1.40) with increasing water hardness. In analyses restricted to individuals who received supplemental iron tablets no significant association between groundwater hardness and ferritin levels was observed. As measured by ferritin levels, residential drinking water calcium content is associated with blood donors- iron levels and risk of iron deficiency. However, effect sizes are small. © 2018 AABB.

Interpretation of changes in water level accompanying fault creep and implications for earthquake prediction.

USGS Publications Warehouse

Wesson, R.L.

1981-01-01

Quantitative calculations for the effect of a fault creep event on observations of changes in water level in wells provide an approach to the tectonic interpretation of these phenomena. For the pore pressure field associated with an idealized creep event having an exponential displacement versus time curve, an analytic expression has been obtained in terms of exponential-integral functions. The pore pressure versus time curves for observation points near the fault are pulselike; a sharp pressure increase (or decrease, depending on the direction of propagation) is followed by more gradual decay to the normal level after the creep event. The time function of the water level change may be obtained by applying the filter - derived by A.G.Johnson and others to determine the influence of atmospheric pressure on water level - to the analytic pore pressure versus time curves. The resulting water level curves show a fairly rapid increase (or decrease) and then a very gradual return to normal. The results of this analytic model do not reproduce the steplike changes in water level observed by Johnson and others. If the procedure used to obtain the water level from the pore pressure is correct, these results suggest that steplike changes in water level are not produced by smoothly propagating creep events but by creep events that propagate discontinuously, by changes in the bulk properties of the region around the well, or by some other mechanism.-Author

Uptake of different species of iodine by water spinach and its effect to growth.

PubMed

Weng, Huan-Xin; Yan, Ai-Lan; Hong, Chun-Lai; Xie, Lin-Li; Qin, Ya-Chao; Cheng, Charles Q

2008-08-01

A hydroponic experiment has been carried out to study the influence of iodine species [iodide (I(-)), iodate (IO(-)(3)), and iodoacetic acid (CH(2)ICOO(-))] and concentrations on iodine uptake by water spinach. Results show that low levels of iodine in the nutrient solution can effectively stimulate the growth of biomass of water spinach. When iodine levels in the nutrient solution are from 0 to 1.0 mg/l, increases in iodine levels can linearly augment iodine uptake rate by the leafy vegetables from all three species of iodine, and the uptake effects are in the following order: CH(2)ICOO(-) >I(-)>IO(-)(3). In addition, linear correlation was observed between iodine content in the roots and shoots of water spinach, and their proportion is 1:1. By uptake of I(-), vitamin C (Vit C) content in water spinach increased, whereas uptake of IO(-)(3) and CH(2)ICOO(-) decreased water spinach Vit C content. Furthermore, through uptake of I(-) and IO(-)(3). The nitrate content in water spinach was increased by different degrees.

Effect of natural gas exsolution on specific storage in a confined aquifer undergoing water level decline.

PubMed

Yager, R M; Fountain, J C

2001-01-01

The specific storage of a porous medium, a function of the compressibility of the aquifer material and the fluid within it, is essentially constant under normal hydrologic conditions. Gases dissolved in ground water can increase the effective specific storage of a confined aquifer, however, during water level declines. This causes a reduction in pore pressure that lowers the gas solubility and results in exsolution. The exsolved gas then displaces water from storage, and the specific storage increases because gas compressibility is typically much greater than that of water or aquifer material. This work describes the effective specific storage of a confined aquifer exsolving dissolved gas as a function of hydraulic head and the dimensionless Henry's law constant for the gas. This relation is applied in a transient simulation of ground water discharge from a confined aquifer system to a collapsed salt mine in the Genesee Valley in western New York. Results indicate that exsolution of gas significantly increased the effective specific storage in the aquifer system, thereby decreasing the water level drawdown.

Effect of natural gas exsolution on specific storage in a confined aquifer undergoing water level decline

USGS Publications Warehouse

Yager, R.M.; Fountain, J.C.

2001-01-01

The specific storage of a porous medium, a function of the compressibility of the aquifer material and the fluid within it, is essentially constant under normal hydrologic conditions. Gases dissolved in ground water can increase the effective specific storage of a confined aquifer, however, during water level declines. This causes a reduction in pore pressure that lowers the gas solubility and results in exsolution. The exsolved gas then displaces water from storage, and the specific storage increases because gas compressibility is typically much greater than that of water or aquifer material. This work describes the effective specific storage of a confined aquifer exsolving dissolved gas as a function of hydraulic head and the dimensionless Henry's law constant for the gas. This relation is applied in a transient simulation of ground water discharge from a confined aquifer system to a collapsed salt mine in the Genesee Valley in western New York. Results indicate that exsolution of gas significantly increased the effective specific storage in the aquifer system, thereby decreasing the water level drawdown.

β-Aminobutyric acid increases abscisic acid accumulation and desiccation tolerance and decreases water use but fails to improve grain yield in two spring wheat cultivars under soil drying.

PubMed

Du, Yan-Lei; Wang, Zhen-Yu; Fan, Jing-Wei; Turner, Neil C; Wang, Tao; Li, Feng-Min

2012-08-01

A pot experiment was conducted to investigate the effect of the non-protein amino acid, β-aminobutyric acid (BABA), on the homeostasis between reactive oxygen species (ROS) and antioxidant defence during progressive soil drying, and its relationship with the accumulation of abscisic acid (ABA), water use, grain yield, and desiccation tolerance in two spring wheat (Triticum aestivum L.) cultivars released in different decades and with different yields under drought. Drenching the soil with 100 µM BABA increased drought-induced ABA production, leading to a decrease in the lethal leaf water potential (Ψ) used to measure desiccation tolerance, decreased water use, and increased water use efficiency for grain (WUEG) under moderate water stress. In addition, at severe water stress levels, drenching the soil with BABA reduced ROS production, increased antioxidant enzyme activity, and reduced the oxidative damage to lipid membranes. The data suggest that the addition of BABA triggers ABA accumulation that acts as a non-hydraulic root signal, thereby closing stomata, and reducing water use at moderate stress levels, and also reduces the production of ROS and increases the antioxidant defence enzymes at severe stress levels, thus increasing the desiccation tolerance. However, BABA treatment had no effect on grain yield of wheat when water availability was limited. The results suggest that there are ways of effectively priming the pre-existing defence pathways, in addition to genetic means, to improve the desiccation tolerance and WUEG of wheat.

How Do River Meanders Change with Sea Level Rise and Fall?

NASA Astrophysics Data System (ADS)

Scamardo, J. E.; Kim, W.

2016-12-01

River meander patterns are controlled by numerous factors, including variations in water discharge, sediment input, and base level. However, the effect of sea level rise and fall on meandering rivers has not been thoroughly quantified. This study examines geomorphic changes to meandering rivers as a result of sea level rise and fall. Twenty experimental runs using coarse-grained walnut shell sediment (D50= 500 microns) in a flume tank (2.4m x 0.6m x 0.1m) tested the optimal initial conditions for creating meandering rivers in a laboratory setting as well as variations in base level rise and fall rates. Geomorphic changes were recorded by camera images every 20 seconds for a duration of 4 hours per experiment. Seventeen experiments tested the effects of changes in initial base levels, water discharge between 200 and 400 mL/min, and sediment to water input ratios between 1:1000 and 1:250 while measuring sinuosity, channel geometry, and the timescale of the channel to reach a stable form. Sinuosity and channel activity increased with increasing water discharge, initial base level, and the sediment to water ratio to a point after which the activity decreased with increasing sediment input. Base-level change experiments used initial conditions of 400 mL/min, a 1:750 sediment to water input ratio, and a 6 cm initial base-level to induce river meanders for the initial 2 hours before base-level change occurred. Three separate experiments investigated the effects of increasing rates of sea level change: 0.07 cm/min, 0.1 cm/min, and 0.2 cm/min. Experimental sea level was decreased constantly from a high-stand of 6 cm to a low-stand of 2 cm back to the high-stand base-level in each experiment. The rates of change in the experiments scale roughly from central to glacial cycles. In all three experiments, sea level fall induced meander cut-off while sea level rise prompted greater rates of meander bend erosion and meander growth. Sinuosity increased by 12%, 13.5%, and 24%, respectively in the three experiments, with most sinuosity changes occurring in the downstream reach of the channel. These experiments could provide insight into long term effects of sea level change on modern meandering fluvial systems as well as provide a key to interpreting past fluvial changes in the stratigraphic record.

Elevated tissue Cr levels, increased plasma oxidative markers, and global hypomethylation of blood DNA in male Sprague-Dawley rats exposed to potassium dichromate in drinking water.

PubMed

Wang, Yu; Wu, Wei; Yao, Chunji; Lou, Jianlin; Chen, Riping; Jin, Lingzhi; Wu, Nanxiang; Gao, Ming; Song, Peng; Tan, Yufeng; Liu, Kecheng

2016-09-01

Hexavalent chromium [Cr (VI)] is prevalent in ground water in some areas, but evidence on the toxic effects of Cr (VI) via ingestion through drinking water remains insufficient. The aims of our study were to investigate the toxic effects of Cr (VI) through oral water ingestion on oxidative stress and DNA methylation. Thirty-two Sprague-Dawley rats were randomly divided into four groups, and exposed to porassium dichromate (K2 Cr2 O7 ; 0, 30, 100, and 300 mg/L) in drinking water for 4 weeks. Mean body weight gain, mean water consumption, clinical chemistry determinations, and oxidative stress levels in plasma were measured. Global DNA methylation changes and DNA methylation status at the promoter of p16 gene were also detected. After 4 weeks, mild anemic effects and increased plasma malondialdehyde (MDA) levels occurred in rats exposed to 100 mg/L or 300 mg/L of Cr (VI). Plasma glutathione peroxidase (GSH-Px) activity decreased in all exposed groups. Global DNA methylation levels were reduced in 100 mg/L and 300 mg/L exposure groups. However, DNA methylation status at the promoter of P16 gene remained unchanged in all K2 Cr2 O7- treated groups. The correlation analysis indicated that increased MDA levels were closely correlated to global DNA hypomethylation. Our results indicated that oral ingestion of Cr (VI) through drinking water caused not only oxidative stress in plasma, but also global DNA hypomethylation in blood cells from male rats, and a good correlation was found between increased MDA levels and reduced global DNA methylation. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1080-1090, 2016. © 2015 Wiley Periodicals, Inc.

Rising water levels and the future of southeastern Louisiana swamp forests

USGS Publications Warehouse

Conner, W.H.; Brody, M.

1989-01-01

An important factor contributing to the deterioration of wetland forests in Louisiana is increasing water levels resulting from eustatic sea-level rise and subsidence. Analyses of long-term water level records from the Barataria and Verret watersheds in southeastern Louisiana indicate an apparent sea level rise of about 1-m per century, mainly the result of subsidence. Permanent study plots were established in cypress-tupelo stands in these two watersheds. The tree, water level, and subsidence data collected in these plots were entered into the U.S. Fish and Wildlife Servicea??s FORFLO bottomland hardwood succession model to determine the long-term effects of rising water levels on forest structure. Analyses were made of 50a??100 years for a cypress-tupelo swamp site in each basin and a bottomland hardwood ridge in the Verret watershed. As flooding increased, less flood tolerant species were replaced by cypress-tupelo within 50 years. As flooding continued, the sites start to become nonforested. From the test analyses, the FORFLO model seems to be an excellent tool for predicting long-term changes in the swamp habitat of south Louisiana.

76 FR 30206 - Southern Nuclear Operating Company, Inc., Vogtle Electric Generating Plant, Unit 1 and 2; Notice...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-24

... High-High, Nominal Trip Setpoint (NTSP) and Allowable Value. The Steam Generator Water Level High-High... previously evaluated is not increased. The Steam Generator Water Level High-High function revised values..., Steam Generator Water Level High-High, Nominal Trip Setpoint (NTSP) and Allowable Value. Function 5c...

Precursory changes in well water level prior to the March, 2000 eruption of Usu Volcano, Japan

NASA Astrophysics Data System (ADS)

Shibata, Tomo; Akita, Fujio

The height of water levels in two wells located near Usu volcano, Japan, changed in a systematic fashion for several months prior to the eruption of Usu volcano on 31 March 2000. In one well, water-level decrease relative to normal levels was first observed at the beginning of October 1999. The decreasing water-level is postulated to result from groundwater flow into cracks widened by intruding magma during dike formation. From the beginning of January 2000, the rate of decrease became higher. During this time, the water level of the second well increased by 0.05 m and then gradually decreased. The water-level changes are consistent with volumetric expansion of magma inside the magma chamber, followed by intrusion of magma into the fracture system associated with widening of cracks. We conclude that water-level observations can provide information that may potentially be used to predict further volcanic eruptions.

Measurement of ground-water storage change and specific yield using the temporal-gravity method near Rillito Creek, Tucson, Arizona

USGS Publications Warehouse

Pool, Donald R.; Schmidt, Werner

1997-01-01

The temporal-gravity method was used to estimate ground-water storage change and specific -yield values at wells near Rillito Creek, Tucson, Arizona, between early December 1992 and early January 1994. The method applies Newton's Law of Gravitation to measure changes in the local gravitational field of the Earth that are caused by changes in the mass and volume of ground water. Gravity at 50 stations in a 6-square-mile area was measured repeatedly relative to gravity at two bedrock stations. Ephemeral recharge through streamflow infiltration during the winter of 1992-93 resulted in water-level rises and gravity increases near Rillito Creek as the volume of ground water in storage increased. Water levels in wells rose as much as 30 feet, and gravity increased as much as 90 microgals. Water levels declined and gravity decreased near the stream after the last major winter flow but continued to rise and increase, respectively, in downgradient areas. Water levels and gravity relative to bedrock were measured at 10 wells. Good linear correlations between water levels and gravity values at five wells nearest the stream allowed for the estimation of specific-yield values for corresponding stratigraphic units assuming the mass change occurred in an infinite horizonal slab of uniform thickness. Specific-yield values for the stream-channel deposits at three wells ranged from 0.15 to 0.34, and correlation coefficients ranged from 0.81 to 0.99. Specific-yield values for the Fort Lowell Formation at three wells ranged from 0.07 to 0.18, and correlation coefficients ranged from 0.82 to 0.93. Specific-yield values were not calculated for the five wells farthest from the stream because of insufficient water-level and gravity change or poor correlations between water level and gravity. Poor correlations between water levels and gravity resulted from ground-water storage change in perched aquifers and in the unsaturated zone near ephemeral streams. Seasonal distributions of ground-water storage change since early December 1992 were evaluated from gravity change at all stations using Gauss's Law. Changes in the distribution of gravity are caused by the flow of water into or out of ground-water storage. Gravity along two profiles was measured frequently to evaluate spatial and temporal distributions of gravity change. Gravity variations indicated preferential ground-water flow to the south in the western part of the study area where the saturate thickness of the aquifer is greatest. Storage changes from December 1992 through early March 1993, mid-May 1993, late August 1993, and early January 1994 were calculated as increases of 7,900, 8,000, 6,300, and 3,700 acre-feet, respectively. Seasonal variations in storage were caused by ground-water withdrawlas, ground-water flow across the boundaries of the gravity-station network, and streamflow infiltration from December 1992 through late April 1993. Most of the estimated recharge of 10,900 acre-feet occurred before mid-May 1993.

Passive Avoidance Training and Recall are Associated With Increased Glutamate Levels in the Intermediate Medial Hyperstriatum Ventrale of the Day-Old Chick

PubMed Central

Daisley, Jonathan N.; Gruss, Michael; Rose, Steven P. R.; Braun, Katharina

1998-01-01

In the young chick, the intermediate medial hyperstriatum ventrale is involved in learning paradigms, including imprinting and passive avoidance learning. Biochemical changes in the intermediate medial hyperstriatum ventrale following learning include an up-regulation of amino-acid transmitter levels and receptor activity. To follow the changes of extracellular amino acid levels during passive avoidance training, we used an in vivo microdialysis technique. Probes were implanted in chicks before training the animals, either on a methyl- anthranylate-or water-coated bead. One hour later, recall was tested in both groups by presenting a similar bead. An increase of extra-cellular glutamate levels accompanied training and testing in both groups; during training, glutamate release was higher in methylanthranylate- trained than in water-trained chicks. When compared with the methylanthranylate-trained chicks during testing, the water-trained chicks showed enhanced extra-cellular glutamate levels. No other amino acid examined showed significant changes. After testing, the chicks were anesthetized and release- stimulated with an infusion of 50 mM potassium. Extra-cellular glutamate and taurine levels were significantly increased in both methylanthranylate-and water-trained chicks. The presentation of methylanthranylate as an. olfactory stimulus significantly enhanced glutamate levels, especially in methylanthranylate-trained chicks. The results suggest that such changes in extra-cellular glutamate levels in the intermediate medial hyperstriatum ventrale accompany pecking at either the water- or the methylanthranylate-bead. The taste of the aversant may be responsible for the greater increases found in methylanthranylate-trained birds. PMID:9920682

Status of ground-water levels and storage volume in the Equus Beds aquifer near Wichita, Kansas, January 2000-January 2003

USGS Publications Warehouse

Hansen, Cristi V.; Aucott, Walter R.

2004-01-01

The Equus Beds aquifer northwest of Wichita, Kansas, was developed to supply water to Wichita residents and for irrigation in south-central Kansas beginning on September 1, 1940. Ground-water pumping for city and agricultural use from the aquifer caused water levels to decline in a large part of the area. Irrigation pumpage in the area increased substantially during the 1970s and 1980s and accelerated water-level declines. A period of water-level rises associated with greater-than-average precipitation and decreased city pumpage from the study area began in 1993. An important factor in the decreased city pumpage was increased use of Cheney Reservoir as a water-supply source by the city of Wichita; as a result, city pumpage from the Equus Beds aquifer during 1993-2002 went from being greater than one-half to slightly less than one-third of Wichita's water usage. Since 1995, the city also has been investigating the use of artificial recharge in the study area to meet future water-supply needs and to protect the aquifer from the intrusion of saltwater from natural and human-related sources to the west. During January 2003, the direction of ground-water flow in the Equus Beds aquifer in the area was generally from west to east similar to predevelopment of the aquifer. The maximum water-level decline since 1940 for the period January 2000 to January 2003 was 29.54 feet in July 2002 at well 3 in the northern part of the area. Cumulative water-level changes from January 2000 to January 2003 typically were less than 4 feet with rises of less than 4 feet common in the central part of the area; however, declines of more than 4 feet occurred in the northwestern and southern parts of the area. The recovery of water levels and aquifer storage volumes from record low levels in October 1992 generally continued to April 2000. The recovery of about 182,000 acre-feet of storage volume in the area from October 1992 to April 2000 represents about a 64-percent recovery of the storage depletion that occurred from August 1940 to October 1992. About 47 percent of this recovery was lost from April 2000 to October 2002 when storage volume in the area decreased by about 86,000 acre-feet. Major contributors to the decreases in water levels and storage volumes were reduced recharge associated with precipitation that was less than in the preceding 5 years and increased irrigation pumpage. The loss of storage probably would have been larger if the continued decrease in city pumpage, which is closely associated with the water-level rises in the central part of the study area, and increased city use of water from Cheney Reservoir had not occurred. The effect of artificial recharge on water levels and storage volume probably was masked by the generally larger decreases in city pumpage in the area.

Links between type E botulism outbreaks, lake levels, and surface water temperatures in Lake Michigan, 1963-2008

USGS Publications Warehouse

Lafrancois, Brenda Moraska; Riley, Stephen C.; Blehert, David S.; Ballmann, Anne E.

2011-01-01

Relationships between large-scale environmental factors and the incidence of type E avian botulism outbreaks in Lake Michigan were examined from 1963 to 2008. Avian botulism outbreaks most frequently occurred in years with low mean annual water levels, and lake levels were significantly lower in outbreak years than in non-outbreak years. Mean surface water temperatures in northern Lake Michigan during the period when type E outbreaks tend to occur (July through September) were significantly higher in outbreak years than in non-outbreak years. Trends in fish populations did not strongly correlate with botulism outbreaks, although botulism outbreaks in the 1960s coincided with high alewife abundance, and recent botulism outbreaks coincided with rapidly increasing round goby abundance. Botulism outbreaks occurred cyclically, and the frequency of outbreaks did not increase over the period of record. Climate change scenarios for the Great Lakes predict lower water levels and warmer water temperatures. As a consequence, the frequency and magnitude of type E botulism outbreaks in the Great Lakes may increase.

Water stress, CO2 and photoperiod influence hormone levels in wheat

NASA Technical Reports Server (NTRS)

Nan, Rubin; Carman, John G.; Salisbury, Frank B.; Campbell, W. F. (Principal Investigator)

2002-01-01

'Super Dwarf' wheat (Triticum aestivum L.) plants have been grown from seed to maturity in the Mir space station where they were periodically exposed, because of microgravity and other constraints, to water deficit, waterlogging, high CO2 levels, and low light intensities. The plants produced many tillers, but none of them produced viable seed. Studies have been initiated to determine why the plants responded in these ways. In the present study, effects of the listed stresses on abscisic acid (ABA), indole-3-acetic acid (IAA) and isopentenyl adenosine ([9R]iP) levels in roots and leaves of plants grown under otherwise near optimal conditions on earth were measured. Hormones were extracted, purified by HPLC, and quantified by noncompetitive indirect ELISA. In response to water deficit, ABA levels increased in roots and leaves, IAA levels decreased in roots and leaves, and [9R]iP levels increased in leaves but decreased in roots. In response to waterlogging, ABA, IAA and [9R]iP levels briefly increased in roots and leaves and then decreased. When portions of the root system were exposed to waterlogging and/or water deficit, ABA levels in leaves increased while [9R]iP and IAA levels decreased. These responses were correlated with the percentage of the root system stressed. At a low photosynthetic photon flux (100 micromoles m-2 s-1), plants grown in continuous light had higher leaf ABA levels than plants grown using an 18 or 21 h photoperiod.

Backwater development by woody debris

NASA Astrophysics Data System (ADS)

Geertsema, Tjitske; Torfs, Paul; Teuling, Ryan; Hoitink, Ton

2017-04-01

Placement of woody debris is a common method for increasing ecological values in river and stream restoration, and is thus widely used in natural environments. Water managers, however, are afraid to introduce wood in channels draining agricultural and urban areas. Upstream, it may create backwater, depending on hydrodynamic characteristics including the obstruction ratio, the Froude number and the surface level gradient. Patches of wood may trigger or counter morphological activity, both laterally, through bank erosion and protection, and vertically, with pool and riffle formation. Also, a permeable construction composed of wood will weather over time. Both morphodynamic activity and weathering cause backwater effects to change in time. The purpose of this study is to quantify the time development of backwater effects caused by woody debris. Hourly water levels gauged upstream and downstream of patches and discharge are collected for five streams in the Netherlands. The water level drop over the woody debris patch relates to discharge in the streams. This relation is characterized by an increasing water level difference for an increasing discharge, up to a maximum. If the discharge increases beyond this level, the water level difference reduces to the value that may represent the situation without woody debris. This reduction depends primarily on the obstruction ratio of the woody debris in the channel cross-section. Morphologic adjustments in the stream and reorientation of the woody material reduce the water level drop over the patches in time. Our results demonstrate that backwater effects can be reduced by optimizing the location where woody debris is placed and manipulating the obstruction ratio. Current efforts are focussed on representing woody debris in a one-dimensional numerical model, aiming to obtain a generic tool to achieve a stream design with woody debris that minimizes backwater.

Water-level data for the Albuquerque Basin and adjacent areas, central New Mexico, period of record through September 30, 2013

USGS Publications Warehouse

Beman, Joseph E.

2014-01-01

The Albuquerque Basin, located in central New Mexico, is about 100 miles long and 25–40 miles wide. The basin is defined as the extent of consolidated and unconsolidated deposits of Tertiary and Quaternary age that encompasses the structural Rio Grande Rift within the basin. Drinking-water supplies throughout the basin were obtained solely from groundwater resources until December 2008, when treatment and distribution of surface water from the Rio Grande began. A population increase of about 20 percent in the basin from 1990 to 2000 and a 22-percent increase from 2000 to 2010 resulted in an increased demand for water. An initial network of wells was established by the U.S. Geological Survey (USGS) in cooperation with the City of Albuquerque from April 1982 through September 1983 to monitor changes in groundwater levels throughout the basin. This network consisted of 6 wells with analog-to-digital recorders and 27 wells where water levels were measured monthly in 1983. Currently (2013), the network consists of 123 wells and piezometers. (A piezometer is a specialized well open to a specific depth in the aquifer, often of small diameter and nested with other piezometers open to different depths.) The USGS, in cooperation with the Albuquerque Bernalillo County Water Utility Authority, currently (2013) measures and reports water levels from the 123 wells and piezometers in the network; this report presents water-level data collected by USGS personnel at those 123 sites through water year 2013.

Water-level data for the Albuquerque Basin and adjacent areas, central New Mexico, period of record through September 30, 2012

USGS Publications Warehouse

Beman, Joseph E.

2013-01-01

The Albuquerque Basin, located in central New Mexico, is about 100 miles long and 25-40 miles wide. The basin is defined as the extent of consolidated and unconsolidated deposits of Tertiary and Quaternary age that encompasses the structural Rio Grande Rift within the basin. Drinking-water supplies throughout the basin were obtained solely from groundwater resources until December 2008, when surface water from the Rio Grande began being treated and integrated into the system. A population increase of about 20 percent in the basin from 1990 to 2000 and a 22 percent increase from 2000 to 2010 resulted in an increased demand for water. An initial network of wells was established by the U.S. Geological Survey (USGS) in cooperation with the City of Albuquerque from April 1982 through September 1983 to monitor changes in groundwater levels throughout the basin. This network consisted of 6 wells with analog-to-digital recorders and 27 wells where water levels were measured monthly in 1983. Currently (2012), the network consists of 126 wells and piezometers. (A piezometer is a specialized well open to a specific depth in the aquifer, often of small diameter and nested with other piezometers open to different depths.) The USGS, in cooperation with the Albuquerque Bernalillo County Water Utility Authority (ABCWUA), currently (2012) measures and reports water levels from the 126 wells and piezometers in the network; this report presents water-level data collected by USGS personnel at those 126 sites through water year 2012.

Investigating sea level rise due to global warming in the teaching laboratory using Archimedes’ principle

NASA Astrophysics Data System (ADS)

Hughes, Stephen; Pearce, Darren

2015-11-01

A teaching laboratory experiment is described that uses Archimedes’ principle to precisely investigate the effect of global warming on the oceans. A large component of sea level rise is due to the increase in the volume of water due to the decrease in water density with increasing temperature. Water close to 0 °C is placed in a beaker and a glass marble hung from an electronic balance immersed in the water. As the water warms, the weight of the marble increases as the water is less buoyant due to the decrease in density. In the experiment performed in this paper a balance with a precision of 0.1 mg was used with a marble 40.0 cm3 and mass of 99.3 g, yielding water density measurements with an average error of -0.008 ± 0.011%.

Long-term (1930-2010) trends in groundwater levels in Texas: influences of soils, landcover and water use.

PubMed

Chaudhuri, Sriroop; Ale, Srinivasulu

2014-08-15

Rapid groundwater depletion has raised grave concerns about sustainable development in many parts of Texas, as well as in other parts of the world. Previous hydrologic investigations on groundwater levels in Texas were conducted mostly on aquifer-specific basis, and hence lacked state-wide panoramic view. The aim of this study was to present a qualitative overview of long-term (1930-2010) trends in groundwater levels in Texas and identify spatial patterns by applying different statistical (boxplots, correlation-regression, hierarchical cluster analysis) and geospatial techniques (Moran's I, Local Indicators of Spatial Association) on 136,930 groundwater level observations from Texas Water Development Board's database. State-wide decadal median water-levels declined from about 14 m from land surface in the 1930s to about 36 m in the 2000s. Number of counties with deeper median water-levels (water-level depth>100 m) increased from 2 to 13 between 1930s and 2000s, accompanied by a decrease in number of counties having shallower median water-levels (water-level depth<25 m) from 134 to 113. Water-level declines across Texas, however, mostly followed logarithmic trends marked by leveling-off phenomena in recent times. Assessment of water-levels by Groundwater Management Areas (GMA), management units created to address groundwater depletion issues, indicated hotspots of deep water-levels in Texas Panhandle and GMA 8 since the 1960s. Contrasting patterns in water use, landcover, geology and soil properties distinguished Texas Panhandle from GMA 8. Irrigated agriculture is the major cause of depletion in the Texas Panhandle as compared to increasing urbanization in GMA 8. Overall our study indicated that use of robust spatial and statistical methods can reveal important details about the trends in water-level changes and shed lights on the associated factors. Due to very generic nature, techniques used in this study can also be applied to other areas with similar eco-hydrologic issues to identify regions that warrant future management actions. Copyright © 2014 Elsevier B.V. All rights reserved.

Simulation of Sub-Drains Performance Using Visual MODFLOW for Slope Water Seepage Problem

NASA Astrophysics Data System (ADS)

Baharuddin, M. F. T.; Tajudin, S. A. A.; Abidin, M. H. Z.; Yusoff, N. A.

2016-07-01

Numerical simulation technique was used for investigating water seepage problem at the Botanic Park Kuala Lumpur. A proposed sub-drains installation in problematic site location was simulated using Modular Three-Dimensional Finite Difference Groundwater Flow (MODFLOW) software. The results of simulation heads during transient condition showed that heads in between 43 m (water seepage occurred at level 2) until 45 m (water seepage occurred at level 4) which heads measurement are referred to mean sea level. However, elevations measurements for level 2 showed the values between 41 to 42 m from mean sea level and elevations for level 4 between 42 to 45 m from mean sea level. These results indicated an increase in heads for level 2 and level 4 between 1 to 2 m when compared to elevations slope at the level 2 and level 4. The head increases surpass the elevation level of the slope area that causing water seepage at level 2 and level 4. In order to overcome this problems, the heads level need to be decrease to 1 until 2 m by using two options of sub-drain dimension size. Sub-drain with the dimension of 0.0750 m (diameter), 0.10 m (length) and using 4.90 m spacing was the best method to use as it was able to decrease the heads to the required levels of 1 to 2 m.

Ground-water monitoring at Santa Barbara, California; Phase 2, Effects of pumping on water levels and on water quality in the Santa Barbara ground-water basin

USGS Publications Warehouse

Martin, Peter

1984-01-01

From July 1978 to January 1980, water levels in the southern part of the Santa Barbara ground-water basin declined more than 100 feet. These water-level declines resulted from increases in municipal pumping since July 1978. The increase in municipal pumping was part of a basin-testing program designed to determine the usable quantity of ground water in storage. The pumping, centered in the city less than 1 mile from the coast, has caused water-level declines to altitudes below sea level in the main water-bearing zones. As a result, the ground-water basin would be subject to saltwater intrusion if the study-period pumpage were maintained or increased. Data indicate that saltwater intrusion has degraded the quality of the water yielded from six coastal wells. During the study period, the six coastal wells all yielded water with chloride concentrations in excess of 250 milligrams per liter, and four of the wells yielded water with chloride concentrations in excess of 1,000 milligrams per liter. Previous investigators believed that saltwater intrusion was limited to the shallow part of the aquifer, directly adjacent to the coast. The possibility of saltwater intrusion into the deeper water-bearing deposits in the aquifer was thought to be remote because an offshore fault truncates these deeper deposits so that they lie against consolidated rocks on the seaward side of the fault. Results of this study indicate, however, that ocean water has intruded the deeper water-bearing deposits, and to a much greater extent than in the shallow part of the aquifer. Apparently the offshore fault is not an effective barrier to saltwater intrusion. No physical barriers are known to exist between the coast and the municipal well field. Therefore, if the pumping rate maintained during the basin-testing program were continued, the degraded water along the coast could move inland and contaminate the municipal supply wells. The time required for the degraded water to move from the coast to the nearest supply well is estimated, using Darcy's equation, to be about 20 years. Management alternatives for controlling saltwater intrusion in the Santa Barbara area include (1) decreasing municipal pumping, (2) increasing the quantity of water available for recharge by releasing surplus water from surface reservoirs to Mission Creek, (3) artificially recharging the basin using injection wells, and (4) locating municipal supply wells farther from the coast and spacing them farther apart in order to minimize drawdown. Continued monitoring of water levels and water quality would enable assessment of the effectiveness of the control measures employed.

Prolonged whole body immersion in cold water: hormonal and metabolic changes.

PubMed

Smith, D J; Deuster, P A; Ryan, C J; Doubt, T J

1990-03-01

To characterize metabolic and hormonal responses during prolonged whole body immersion, 16 divers wearing dry suits completed four immersions in 5 degrees C water during each of two 5-day air saturation dives at 6.1 meters of sea water. One immersion began in the AM (1000 h) and one began in the PM (2200 h) to evaluate diurnal variations. Venous blood samples were obtained before and after completion of each immersion. Cortisol and ACTH levels demonstrated diurnal variation, with larger increases occurring after PM immersions. A greater than three-fold postimmersion increase occurred in norepinephrine (NE). There were significant increases in triiodothyronine (T3) uptake and epinephrine, but no change in T3, thyroxine, thyrotrophic hormone, and dopamine. Postimmersion free fatty acid levels increased 409% from preimmersion levels; glucose levels declined, and lactate increased significantly. Only changes in NE correlated significantly with changes in rectal temperature. In summary, when subjects are immersed in cold water for prolonged periods, with a slow rate of body cooling afforded by thermal protection and intermittent exercise, hormonal and metabolic changes occur that are similar in direction and magnitude to short-duration unprotected exposures. Except for cortisol and ACTH, none of the other measured variables exhibited diurnal alterations.

Do shrubs reduce the adverse effects of grazing on soil properties?

USGS Publications Warehouse

Eldridge, David J.; Beecham, Genevieve; Grace, James B.

2015-01-01

Increases in the density of woody plants are a global phenomenon in drylands, and large aggregations of shrubs, in particular, are regarded as being indicative of dysfunctional ecosystems. There is increasing evidence that overgrazing by livestock reduces ecosystem functions in shrublands, but that shrubs may buffer the negative effects of increasing grazing. We examined changes in water infiltration and nutrient concentrations in soils under shrubs and in their interspaces in shrublands in eastern Australia that varied in the intensity of livestock grazing. We used structural equation modelling to test whether shrubs might reduce the negative effects of overgrazing on infiltration and soil carbon and nitrogen (henceforth ‘soil nutrients’). Soils under shrubs and subject to low levels of grazing were more stable and had greater levels of soil nutrients. Shrubs had a direct positive effect on soil nutrients; but, grazing negatively affected nutrients by increasing soil bulk density. Structural equation modelling showed that shrubs had a direct positive effect on water flow under ponded conditions but also enhanced water flow, indirectly, through increased litter cover. Any positive effects of shrubs on water flow under low levels of grazing waned at high levels of grazing. Our results indicate that shrubs may reduce the adverse effects of grazing on soil properties. Specifically, shrubs could restrict access to livestock and therefore protect soils and plants beneath their canopies. Low levels of grazing are likely to ensure the retention of soil water and soil carbon and nitrogen in shrubland soils.

A population-based case-control study of drinking-water nitrate and congenital anomalies using Geographic Information Systems (GIS) to develop individual-level exposure estimates.

PubMed

Holtby, Caitlin E; Guernsey, Judith R; Allen, Alexander C; Vanleeuwen, John A; Allen, Victoria M; Gordon, Robert J

2014-02-05

Animal studies and epidemiological evidence suggest an association between prenatal exposure to drinking water with elevated nitrate (NO3-N) concentrations and incidence of congenital anomalies. This study used Geographic Information Systems (GIS) to derive individual-level prenatal drinking-water nitrate exposure estimates from measured nitrate concentrations from 140 temporally monitored private wells and 6 municipal water supplies. Cases of major congenital anomalies in Kings County, Nova Scotia, Canada, between 1988 and 2006 were selected from province-wide population-based perinatal surveillance databases and matched to controls from the same databases. Unconditional multivariable logistic regression was performed to test for an association between drinking-water nitrate exposure and congenital anomalies after adjusting for clinically relevant risk factors. Employing all nitrate data there was a trend toward increased risk of congenital anomalies for increased nitrate exposure levels though this was not statistically significant. After stratification of the data by conception before or after folic acid supplementation, an increased risk of congenital anomalies for nitrate exposure of 1.5-5.56 mg/L (2.44; 1.05-5.66) and a trend toward increased risk for >5.56 mg/L (2.25; 0.92-5.52) was found. Though the study is likely underpowered, these results suggest that drinking-water nitrate exposure may contribute to increased risk of congenital anomalies at levels below the current Canadian maximum allowable concentration.

A Population-Based Case-Control Study of Drinking-Water Nitrate and Congenital Anomalies Using Geographic Information Systems (GIS) to Develop Individual-Level Exposure Estimates

PubMed Central

Holtby, Caitlin E.; Guernsey, Judith R.; Allen, Alexander C.; VanLeeuwen, John A.; Allen, Victoria M.; Gordon, Robert J.

2014-01-01

Animal studies and epidemiological evidence suggest an association between prenatal exposure to drinking water with elevated nitrate (NO3-N) concentrations and incidence of congenital anomalies. This study used Geographic Information Systems (GIS) to derive individual-level prenatal drinking-water nitrate exposure estimates from measured nitrate concentrations from 140 temporally monitored private wells and 6 municipal water supplies. Cases of major congenital anomalies in Kings County, Nova Scotia, Canada, between 1988 and 2006 were selected from province-wide population-based perinatal surveillance databases and matched to controls from the same databases. Unconditional multivariable logistic regression was performed to test for an association between drinking-water nitrate exposure and congenital anomalies after adjusting for clinically relevant risk factors. Employing all nitrate data there was a trend toward increased risk of congenital anomalies for increased nitrate exposure levels though this was not statistically significant. After stratification of the data by conception before or after folic acid supplementation, an increased risk of congenital anomalies for nitrate exposure of 1.5–5.56 mg/L (2.44; 1.05–5.66) and a trend toward increased risk for >5.56 mg/L (2.25; 0.92–5.52) was found. Though the study is likely underpowered, these results suggest that drinking-water nitrate exposure may contribute to increased risk of congenital anomalies at levels below the current Canadian maximum allowable concentration. PMID:24503976

Progress report on the ground-water, surface-water, and quality-of-water monitoring program, Black Mesa Area, northeastern Arizona; 1988-89

USGS Publications Warehouse

Hart, R.J.; Sottilare, J.P.

1989-01-01

The Black Mesa monitoring program in Arizona is designed to determine long-term effects on the water resources of the area resulting from withdrawals of groundwater from the N aquifer by the strip-mining operation of Peabody Coal Company. Withdrawals by Peabody Coal Company increased from 95 acre-ft in 1968 to 4 ,090 acre-ft in 1988. The N aquifer is an important source of water in the 5,400-sq-mi Black Mesa area on the Navajo and Hopi Indian Reservations. Water levels in the confined area of the aquifer declined as much as 19.7 ft near Low Mountain from 1988 to 1989. Part of the decline in the measured municipal wells may be due to local pumping. During 1965-88, water levels in wells that tap the unconfined area of the aquifer have not declined significantly and have risen in many areas. Chemical analysis indicate no significant changes in the quality of water from wells that tap the N aquifer or from springs that discharge from several stratigraphic units, including the N aquifer, since pumping began at the mine. The groundwater flow model developed for the study area in 1988 was updated using pumpage data for 1985-88. The model simulated a steady decline in water levels in observations wells developed in areas of unconfined groundwater. Measured water levels in these wells did not show this trend but indicated that water levels remained the same or increased. The model accurately simulated water levels in most observation wells developed in areas of confined groundwater. (USGS)

Exposure to low level of arsenic and lead in drinking water from Antofagasta city induces gender differences in glucose homeostasis in rats.

PubMed

Palacios, Javier; Roman, Domingo; Cifuentes, Fredi

2012-08-01

Populations chronically exposed to arsenic in drinking water often have increased prevalence of diabetes mellitus. The purpose of this study was to compare the glucose homeostasis of male and female rats exposed to low levels of heavy metals in drinking water. Treated groups were Sprague-Dawley male and female rats exposed to drinking water from Antofagasta city, with total arsenic of 30 ppb and lead of 53 ppb for 3 months; control groups were exposed to purified water by reverse osmosis. The two treated groups in both males and females showed arsenic and lead in the hair of rats. The δ-aminolevulinic acid dehydratase was used as a sensitive biomarker of arsenic toxicity and lead. The activity of δ-aminolevulinic acid dehydratase was reduced only in treated male rats, compared to the control group. Treated males showed a significantly sustained increase in blood glucose and plasma insulin levels during oral glucose tolerance test compared to control group. The oral glucose tolerance test and the homeostasis model assessment of insulin resistance demonstrated that male rats were insulin resistant, and females remained sensitive to insulin after treatment. The total cholesterol and LDL cholesterol increased in treated male rats vs. the control, and triglyceride increased in treated female rats vs. the control. The activity of intestinal Na+/glucose cotransporter in male rats increased compared to female rats, suggesting a significant increase in intestinal glucose absorption. The findings indicate that exposure to low levels of arsenic and lead in drinking water could cause gender differences in insulin resistance.

Influence of chilling and drought on water relations and abscisic acid accumulation in bean

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vernieri, P.; Pardossi, A.; Tognoni, F.

Intact bean seedlings were subjected to either chilling (4{degree}C) or drought stress. Leaf water relations and abscisic acid (ABA) content were monitored throughout a stress-recovery cycle. Chilling at low relative humidity (RH) and drought caused similar water deficits, as indicated by the decline in relative water content and water potentials, but they had different effects on ABA accumulation. There was a rapid increase in ABA levels in the leaves of water-deprived plants while only slight ABA accumulation was observed after 48 h of chilling (4{degree}C). After 24 h cold treatment there were large changes in turgor but no change inmore » ABA content. Plants chilled for 24 h accumulated ABA only when transferred to recovery conditions (20{degree}C, 90-95% RH, in the dark) to an extent that was related to the rate of leaf rehydration. When the chilling treatment was performed in a water-saturated atmosphere, plants did not suffer any water stress and ABA levels did not increase over a period of 48 h. However, when the chilling treatment lasted for a longer period (72 h), a significant increase in ABA levels was found also in the absence of water deficit. Experiments performed with leaf discs incubated in a mannitol solution (osmotic potential {minus}1{center dot}6 MPa) at different temperatures indicated that low temperature markedly inhibits ABA synthesis and that water stress induces increases in ABA content only at non-limiting warm temperatures.« less

Simulated response to pumping stress in the Sparta aquifer of southeastern Arkansas and north-central Louisiana, 1998-2027

USGS Publications Warehouse

Hays, Phillip D.; Lovelace, John K.; Reed, Thomas B.

1998-01-01

The Sparta aquifer in southeastern Arkansas and north-central Louisiana is a major water resource for municipal, industrial, and agricultural uses. In recent years, the demand for water in some areas has resulted in withdrawals from the Sparta that significantly exceed recharge to the aquifer. Considerable drawdown has occurred in the potentiometric surface, and water users and managers alike have begun to question the ability of the aquifer to supply water for the long term. Large cones of depression are centered beneath the Grand Prairie area and the cities of Pine Bluff and El Dorado in Arkansas, and Monroe in Louisiana. Water levels in the aquifer have declined at rates greater than 1 foot per year for more than a decade in much of southern Arkansas and northern Louisiana and are now below the top of the formation in parts of Union and Columbia Counties, Arkansas, and in several areas of Louisiana. Problems related to over draft in the Sparta could result in increased drilling and pumping costs, loss of yield, salt-water intrusion, and decrease in water quality in areas of large drawdown. The effects of current ground-water withdrawals and potential future withdrawals on water availability are major concerns of water managers and users as well as the general public in the two States. The Sparta model-a regional scale, digital ground-water flow model-was first calibrated in the mid-1980's. The model was updated and reverified using 1995-97 data. Visual inspection of the observed (1996-97) and simulated potentiometric surfaces, statistical analysis of the error for the original calibration and current reverification, and comparison of observed versus simulated hydro graphs indicates that the model is simulating conditions in the aquifer within acceptable error, and the quality of current (1998) model results is similar to the original model calibration results. When stressed with current withdrawal volumes and distributions, the model is able to simulate currently observed heads effectively as heads were simulated in the original calibration period. Five pumping scenarios were simulated over a 30-year period based on (1) current pumping rates, (2) current rates of change in pumping, (3) decreased pumping in selected areas, (4) increased pumping in selected areas, and (5) redistribution and increase of pumping in selected areas. Model results show that although continued pumping at current rates will result in relatively minor declines in water levels (scenario 1 above), continued pumping at currently observed rates of change will result in drastic declines across large areas of focused withdrawals (scenario 2). Under the first scenario-in which current pumping rates are input to the model for the 30-year simulation period-water levels in the middle of the cones of depression centered on El Dorado and Monroe decrease less than 10 feet. In the second scenario-in which the current rate of change in pumpage is applied to the model-substantial declines occur in the proximity of most major pumpage centers. During the 1998-2027 model period, predicted water levels decline from 307 feet below sea level to 438 feet below sea level near El Dorado, from 58 feet below sea level to 277 feet below sea level near Pine Bluff, but only by about 25 feet-from 202 feet below sea level to 225 feet below sea level near Monroe. In the third scenario-in which minimum predicted water use figures supplied by selected facilities in Arkansas and decreased pumping estimates for Louisiana are applied to the model-simulated water levels are substantially higher at cones of depression around the major pumping centers of Monroe and El Dorado as compared to initial (1997) values. During the 1998-2027 model period, predicted water levels near Monroe increase from 202 feet below sea level to 133 feet below sea level; water levels near El Dorado increase from 307 feet below sea level to 123 feet below sea level. For the fourth scenario-in which maxi mum pr

Water-level data for the Albuquerque Basin and adjacent areas, central New Mexico, period of record through September 30, 2015

USGS Publications Warehouse

Beman, Joseph E.; Bryant, Christina F.

2016-10-27

The Albuquerque Basin, located in central New Mexico, is about 100 miles long and 25–40 miles wide. The basin is hydrologically defined as the extent of consolidated and unconsolidated deposits of Tertiary and Quaternary age that encompasses the structural Rio Grande Rift between San Acacia to the south and Cochiti Lake to the north. Drinking-water supplies throughout the basin were obtained solely from groundwater resources until December 2008, when the Albuquerque Bernalillo County Water Utility Authority (ABCWUA) began treatment and distribution of surface water from the Rio Grande through the San Juan-Chama Drinking Water Project. A 20-percent population increase in the basin from 1990 to 2000 and a 22-percent population increase from 2000 to 2010 may have resulted in an increased demand for water in areas within the basin.An initial network of wells was established by the U.S. Geological Survey (USGS) in cooperation with the City of Albuquerque from April 1982 through September 1983 to monitor changes in groundwater levels throughout the Albuquerque Basin. In 1983, this network consisted of 6 wells with analog-to-digital recorders and 27 wells where water levels were measured monthly. The network currently (2015) consists of 124 wells and piezometers. (A piezometer is a specialized well open to a specific depth in the aquifer, often of small diameter and nested with other piezometers open to different depths.) The USGS, in cooperation with the ABCWUA, currently (2015) measures and reports water levels from the 124 wells and piezometers in the network; this report presents water-level data collected by USGS personnel at those 124 sites through water year 2015 (October 1, 2014, through September 30, 2015).

Leaf Abscission Induced by Ethylene in Water-Stressed Intact Seedlings of Cleopatra Mandarin Requires Previous Abscisic Acid Accumulation in Roots.

PubMed Central

Gomez-Cadenas, A.; Tadeo, F. R.; Talon, M.; Primo-Millo, E.

1996-01-01

The involvement of abscisic acid (ABA) in the process of leaf abscission induced by 1-aminocyclopropane-1-carboxylic acid (ACC) transported from roots to shoots in Cleopatra mandarin (Citrus reshni Hort. ex Tan.) seedlings grown under water stress was studied using norflurazon (NF). Water stress induced both ABA (24-fold) and ACC (16-fold) accumulation in roots and arrested xylem flow. Leaf bulk ABA also increased (8-fold), although leaf abscission did not occur. Shortly after rehydration, root ABA and ACC returned to their prestress levels, whereas sharp and transitory increases of ACC (17-fold) and ethylene (10-fold) in leaves and high percentages of abscission (up to 47%) were observed. NF suppressed the ABA and ACC accumulation induced by water stress in roots and the sharp increases of ACC and ethylene observed after rewatering in leaves. NF also reduced leaf abscission (7-10%). These results indicate that water stress induces root ABA accumulation and that this is required for the process of leaf abscission to occur. It was also shown that exogenous ABA increases ACC levels in roots but not in leaves. Collectively, the data suggest that ABA, the primary sensitive signal to water stress, modulates the levels of ethylene, which is the hormonal activator of leaf abscission. This assumption implies that root ACC levels are correlated with root ABA amounts in a dependent way, which eventually links water status to an adequate, protective response such as leaf abscission. PMID:12226398

Water deficit affected flavonoid accumulation by regulating hormone metabolism in Scutellaria baicalensis Georgi roots.

PubMed

Yuan, Yuan; Liu, Yunjun; Wu, Chong; Chen, Shunqin; Wang, Zhouyong; Yang, Zhaochun; Qin, Shuangshuang; Huang, Luqi

2012-01-01

The content of flavonoids especially baicalin and baicalein determined the medical quality of Scutellaria baicalensis which is a Chinese traditional medicinal plant. Here, we investigated the mechanism responsible for the content and composition of flavonoids in S. baicalensis under water deficit condition. The transcription levels of several genes which are involved in flavonoid biosynthesis were stimulated by water deficit. Under water deficit condition, fifteen up-regulated proteins, three down-regulated proteins and other six proteins were detected by proteomic analysis. The identified proteins include three gibberellin (GA)- or indoleacetic acid (IAA)-related proteins. Decreased endogenous GAs level and increased IAA level were observed in leaves of S. baicalensis which was treated with water deficit. Exogenous application of GA or α-naphthalene acelic acid (NAA) to plants grown under water deficit conditions led to the increase of endogenous GAs and the decrease of IAA and flavonoids, respectively. When the synthesis pathway of GA or IAA in plants was inhibited by application with the inhibitors, flavonoid levels were recovered. These results indicate that water deficit affected flavonoid accumulation might through regulating hormone metabolism in S. baicalensis Georgi.

The effects of channel excavation on water-quality characteristics of the Black River and on ground-water levels near Dunn, North Carolina

USGS Publications Warehouse

Simmons, C.E.; Watkins, S.A.

1982-01-01

During 1976-81 data were collected at three sites on the Black River near Dunn, N.C., to define the effects of channel excavation on stream quality and on ground-water levels in nearby areas. One of the data sites was located upstream from the five-mile long excavated reach and served as a background station. Changes in various characteristics of this Coastal Plain stream were determined by comparing data collected before, during, and after the construction period. After deepening of the channel by more than 2 feet, ground-water levels within 100 feet of the stream declined a proportionate amount; however, levels in a well 500 feet from the stream were unchanged. Flow velocities during channel deepening were 100 percent higher than velocities prior to construction. An average increase in water temperatures of about one degree Celsius was observed following removal of trees and brush that provided shading to the stream. After construction, concentrations of dissolved oxygen also increased. The percent of saturation increased 20 to 25 percent in the lower values. Maximum concentrations of suspended sediment increased from about 75 mg/L prior to construction to over 2000 mg/L during construction. Within a year after construction, levels of suspended sediment during stormflow had decreased but remained 5 to 10 times greater than preconstruction levels. Little or no change occurred in pH, total-dissolved solids, nitrogen, phosphorus, and bacteria.

Impact of Plumbing Age on Copper Levels in Drinking Water

EPA Science Inventory

Theory and limited practical experiences suggest that higher copper levels in drinking water tap samples are typically associated with newer plumbing systems, and levels decrease with increasing plumbing age. Past researchers have developed a conceptual model to explain the “agin...

The competing impacts of climate change and nutrient reductions on dissolved oxygen in Chesapeake Bay

NASA Astrophysics Data System (ADS)

Irby, Isaac D.; Friedrichs, Marjorie A. M.; Da, Fei; Hinson, Kyle E.

2018-05-01

The Chesapeake Bay region is projected to experience changes in temperature, sea level, and precipitation as a result of climate change. This research uses an estuarine-watershed hydrodynamic-biogeochemical modeling system along with projected mid-21st-century changes in temperature, freshwater flow, and sea level rise to explore the impact climate change may have on future Chesapeake Bay dissolved-oxygen (DO) concentrations and the potential success of nutrient reductions in attaining mandated estuarine water quality improvements. Results indicate that warming bay waters will decrease oxygen solubility year-round, while also increasing oxygen utilization via respiration and remineralization, primarily impacting bottom oxygen in the spring. Rising sea level will increase estuarine circulation, reducing residence time in bottom waters and increasing stratification. As a result, oxygen concentrations in bottom waters are projected to increase, while oxygen concentrations at mid-depths (3 < DO < 5 mg L-1) will typically decrease. Changes in precipitation are projected to deliver higher winter and spring freshwater flow and nutrient loads, fueling increased primary production. Together, these multiple climate impacts will lower DO throughout the Chesapeake Bay and negatively impact progress towards meeting water quality standards associated with the Chesapeake Bay Total Maximum Daily Load. However, this research also shows that the potential impacts of climate change will be significantly smaller than improvements in DO expected in response to the required nutrient reductions, especially at the anoxic and hypoxic levels. Overall, increased temperature exhibits the strongest control on the change in future DO concentrations, primarily due to decreased solubility, while sea level rise is expected to exert a small positive impact and increased winter river flow is anticipated to exert a small negative impact.

Municipal water supplies in Lee County, Florida, 1974

USGS Publications Warehouse

O'Donnell, T. H.

1977-01-01

In 1974 the total pumpage for Lee County, Fla., municipal supplies reached 5,700 Mgal (million gallons annually), an increase of 54 percent over 1970 levels. Pumpage from individual sources included: Caloosahatchee River, 1,312 Mgal; water-table aquifer, 2,171 Mgal; the water-bearing zone in the Tamiami Formation, 340 Mgal; the water-bearing zone in the upper part of the Hawthorn Formation, 1,399 Mgal; the saline water zones in the lower part of the Hawthorn Formation and the Suwannee Limestone, 483 Mgal. Among the various sources, the water-table aquifer showed the greatest increase in municipal pumpage over 1970 levels (60 percent) while the saline zones in the lower part of the Hawthorn Formation and Suwannee Limestone showed the least (40 percent). Intensive pumpage from the water bearing zone in the upper part of the Hawthorn Formation has caused a progressive decline in water levels in wells tapping that zone. The quality of fresh ground water in areas unaffected by intrusion of saline water, generally meets all the recommended limits of the Environmental Protection Agency. The chemical treatment processes utilized by water plants in the county are generally effective in producing finished water that meets EPA preliminary drinking water standards. (Woodard-USGS)

Regional water table (2000) and ground-water-level changes in the Mojave River and the Morongo ground-water basins, southwestern Mojave Desert, California

USGS Publications Warehouse

Smith, Gregory A.

2003-01-01

The Mojave River and Morongo ground-water basins are in the southwestern part of the Mojave Desert in southern California. Ground water from these basins supplies a major part of the water requirements for the region. The continuous population growth in this area has resulted in ever-increasing demands on local ground-water resources. The collection and interpretation of ground-water data helps local water districts, military bases, and private citizens gain a better understanding of the ground-water systems, and consequently, water availability. During 2000, the U. S. Geological Survey and other agencies made approximately 2,500 water-level measurements in the Mojave River and the Morongo ground-water basins. These data document recent conditions and, when compared with previous data, changes in ground-water levels. A water-level contour map was drawn using data from about 500 wells, providing coverage for most of the basins. Twenty-nine hydrographs show long-term (up to 70 years) water-level conditions throughout the basins, and 13 short-term (1996 to 2000) hydrographs show the effects of recharge and discharge along the Mojave River. In addition, a water-level-change map was compiled to compare 1998 and 2000 water-levels throughout the basins. In the Mojave River ground-water basins, water-level data showed little change from 1998 to 2000, with the exception of areas along the Mojave River. Water levels along the Mojave River were typically in decline or unchanged, with exceptions near the Hodge and the Lenwood outlet, where water levels rose in response to artificial recharge. The Morongo ground-water basin had virtually no change in water levels from 1998 to 2000, with the exception of Yucca Valley, where artificial recharge and ground-water withdrawal continues.

The effect of head-down tilt and water immersion on intracranial pressure in nonhuman primates

NASA Technical Reports Server (NTRS)

Keil, Lanny C.; Mckeever, Kenneth H.; Skidmore, Michael G.; Hines, John; Severs, Walter B.

1992-01-01

Intracranial pressure (ICP) is investigated in primates during and after -6-deg head-down tilt (HDT) and immersion in water to examine the effects of the headward fluid shift related to spaceflight. Following the HDT the primates are subjected to head-out thermoneutral water immersion, and the ICP is subsequently measured. ICP is found to increase from 3.8 +/- 1.1 to 5.3 +/- 1.3 mm Hg during the horizontal control period. ICP stabilizes at -6.3 +/- 1.3 mm Hg and then increases to -2.2 +/- 1.9 mm Hg during partial immersion, and ICP subsequently returns to preimmersion levels after immersion. These data indicate that exposure to HDT or water immersion lead to an early sharp increase in ICP, and water immersion alone leads to higher ICP levels. A significant conclusion of the work is that the ICP did not approach pathological levels, and this finding is relevant to human spaceflight research.

Ground-water levels in Huron County, Michigan, January 1996 through December 1996

USGS Publications Warehouse

Sweat, M.J.

1997-01-01

In 1990, the U.S. Geological Survey (USGS) completed a study of the hydrogeology of Huron County, Michigan (Sweat, 1991). In 1993, Huron County and the USGS entered into an agreement to continue collecting water levels at selected wells throughout Huron County. As part of the agreement, the USGS has provided training and instrumentation for County personnel to measure, on a quarterly basis, the depth to water below the land surface in selected wells. The agreement includes the operation of continuous water-level recorders installed on four wells in Bingham, Fairhaven, Grant and Lake Townships (fig. 1). County personnel make quarterly water-level measurements of 22 other wells. Once each year, County personnel are accompanied by USGS personnel who provide a quality assurance/quality control check of all measurements being made.Precipitation and the altitude of Lake Huron are good indicators of general climatic conditions and, therefore, provide an environmental context for ground-water levels in Huron County. Figure 2 shows the mean monthly water-level altitude of Lake Huron, averaged from measurements made by U.S. Army Corps of Engineers at two sites, and mean monthly precipitation as recorded in Huron County, for the period October 1988 through December 1996. In general, Lake Huron water levels in 1996 were about the same as they were from 1992-94 (NOAA, 1988-96). Precipitation was generally within the normal range, but was lower than 1993 or 1994. Rainfall during May, June, and July was, cumulatively, about 8.5 inches less in 1995 than in 1994.Hydrographs are presented for each of four wells with water-level recorders. Quarterly water-level measurements and range of water levels during 1996 for the other 22 wells are shown graphically and tabulated.In general, water levels in the glaciofluvial aquifer reflect seasonal variations, with maximum depths to water occurring in late summer and early fall and minimum depths to water occurring in late winter and early spring. In general, wells completed in the lower part of the Marshall aquifer continue to show an increase in water-level altitude from the original project period (1988-90); wells completed in the upper part of the Marshall aquifer showed little variation in water-level altitudes compared to previous years. Wells completed in the Saginaw aquifer continued to show higher water level altitudes in 1995, not only near the lake but also farther inland, while water-level altitudes in wells completed in the Coldwater confining unit showed a small increase from the original project period. Water-level altitudes were higher in the southwest and central parts of the County during 1995 than in the previous year, and water-level altitudes were for the most-part unchanged in the northwest, northeast, and southeast parts of the county during 1995. All wells with recorders had lower water levels in September 1995 than in 1993-94. Lower than average precipitation during May-August is the primary reason for lower levels.

Water-level data for the Albuquerque Basin and adjacent areas, central New Mexico, period of record through September 30, 2011

USGS Publications Warehouse

Beman, Joseph E.

2012-01-01

The Albuquerque Basin, located in central New Mexico, is about 100 miles long and 25–40 miles wide. The basin is defined as the extent of consolidated and unconsolidated deposits of Tertiary and Quaternary age that encompasses the structural Rio Grande Rift within the basin. Drinking-water supplies throughout the basin were obtained solely from groundwater resources until December 2008, when surface water from the Rio Grande began being treated and integrated into the system. An increase of about 20 percent in the basin human population from 1990 to 2000 and of about 22 percent increase from 2000 to 2010 also resulted in an increased demand for water. A network of wells was established by the U.S. Geological Survey in cooperation with the City of Albuquerque from April 1982 through September 1983 to monitor changes in groundwater levels throughout the basin. This network consisted of 6 wells with analog-to-digital recorders and 27 wells where water levels were measured monthly in 1983. Currently (2011), the network consists of 126 wells and piezometers (a piezometer is a specialized well open to a specific depth in the aquifer and is often of small diameter and nested with other piezometers open to different depths). This report presents water-level data collected by U.S. Geological Survey personnel at those 126 sites through water year 2011 to better help the Albuquerque Bernalillo County Water Utility Authority manage water use.

Differential effects of exposure to parasites and bacteria on stress response in turbot Scophthalmus maximus simultaneously stressed by low water depth.

PubMed

Rodríguez-Quiroga, J J; Otero-Rodiño, C; Suárez, P; Nieto, T P; García Estévez, J M; San Juan, F; Soengas, J L

2017-07-01

The stress response of turbot Scophthalmus maximus was evaluated in fish maintained 8 days under different water depths, normal (NWD, 30 cm depth, total water volume 40 l) or low (LWD, 5 cm depth, total water volume 10 l), in the additional presence of infection-infestation of two pathogens of this species. This was caused by intraperitoneal injection of sublethal doses of the bacterium Aeromonas salmonicida subsp. salmonicida or the parasite Philasterides dicentrarchi (Ciliophora:Scuticociliatida). The LWD conditions were stressful for fish, causing increased levels of cortisol in plasma, decreased levels of glycogen in liver and nicotinamide adenine dinucleotide phosphate (NADP) and increased activities of G6Pase and GSase. The presence of bacteria or parasites in fish under NWD resulted in increased cortisol levels in plasma whereas in liver, changes were of minor importance including decreased levels of lactate and GSase activity. The simultaneous presence of bacteria and parasites in fish under NWD resulted a sharp increase in the levels of cortisol in plasma and decreased levels of glucose. Decreased levels of glycogen and lactate and activities of GSase and glutathione reductase (GR), as well as increased activities of glucose-6-phosphate dehydrogenase (G6PDH), 6-phosphogluconate dehydrogenase (6PGDH) and levels of nicotinamide adenine dinucleotide phosphate (NADPH) occurred in the same fish in liver. Finally, the presence of pathogens in S. maximus under stressful conditions elicited by LWD resulted in synergistic actions of both type of stressors in cortisol levels. In liver, the presence of bacteria or parasites induced a synergistic action on several variables such as decreased activities of G6Pase and GSase as well as increased levels of NADP and NADPH and increased activities of GPase, G6PDH and 6PGDH. © 2017 The Fisheries Society of the British Isles.

Water-level fluctuations influence sediment porewater chemistry and methylmercury production in a flood-control reservoir.

PubMed

Eckley, Chris S; Luxton, Todd P; Goetz, Jennifer; McKernan, John

2017-03-01

Reservoirs typically have elevated fish mercury (Hg) levels compared to natural lakes and rivers. A unique feature of reservoirs is water-level management which can result in sediment exposure to the air. The objective of this study is to identify how reservoir water-level fluctuations impact Hg cycling, particularly the formation of the more toxic and bioaccumulative methylmercury (MeHg). Total-Hg (THg), MeHg, stable isotope methylation rates and several ancillary parameters were measured in reservoir sediments (including some in porewater and overlying water) that are seasonally and permanently inundated. The results showed that sediment and porewater MeHg concentrations were over 3-times higher in areas experiencing water-level fluctuations compared to permanently inundated sediments. Analysis of the data suggest that the enhanced breakdown of organic matter in sediments experiencing water-level fluctuations has a two-fold effect on stimulating Hg methylation: 1) it increases the partitioning of inorganic Hg from the solid phase into the porewater phase (lower log K d values) where it is more bioavailable for methylation; and 2) it increases dissolved organic carbon (DOC) in the porewater which can stimulate the microbial community that can methylate Hg. Sulfate concentrations and cycling were enhanced in the seasonally inundated sediments and may have also contributed to increased MeHg production. Overall, our results suggest that reservoir management actions can have an impact on the sediment-porewater characteristics that affect MeHg production. Such findings are also relevant to natural water systems that experience wetting and drying cycles, such as floodplains and ombrotrophic wetlands. Published by Elsevier Ltd.

Evaluating Capability of Devils Lake Emergency Outlets in Lowering Lake Water Levels While Controlling flooding Damage to Downstream

NASA Astrophysics Data System (ADS)

Scanlon, B. R.; Zhang, Z.; Sun, A.; Save, H.; Mueller Schmied, H.; Wada, Y.; Doll, P. M.; Eisner, S.

2016-12-01

Devils Lake is an endorheic lake locate in the Red River of the North Basin with a natural outlet at a level of 444.7 meters above the sea level flowing into the Sheyenne River. Historical accumulation of salts has dramatically increased the concentration of salts in the lake, particularly of the sulfates, that are much greater than the surrounding water bodies. Since 1993, the lake water level has risen by nearly 10 meters and caused extensive flooding in the surrounding area, and greatly increased the chance of natural spillage to the Sheyenne River. To mitigate Devils Lake flooding and to prevent its natural spillage, two outlets were constructed at the west and east sides of the lake to drain the water to the Sheyenne River in a controlled fashion. However, pumping water from Devils Lake has degraded water quality of the Sheyenne River. In an earlier study, we coupled Soil and Water Assessment Tools (SWAT) and CE-QUAL-W2 models to investigate the changes of sulfate distribution as the lake water level rises. We found that, while operating the two outlets has lowered Devils Lake water level by 0.7 meter, it has also significantly impaired the Sheyenne River water quality, increasing the Sheyenne River average sulfate concentration from 105 to 585 mg l-1 from 2012 to 2014 In this study, we investigate the impact of the outlets on the Sheyenne River floodplain by coupling SWAT and HEC-RAS model. The SWAT model performed well in simulating daily streamflow in the Sheyenne River with R2>0.56 and ENS > 0.52. The simulated water depths and floodplain by HEC-RAS model for the Sheyenne River agreed well with observations. Operating the outlets from April to October can draw down the Devil Lake water level by 0.45 m, but the drained water would almost double the extension of the Sheyenne River floodplain and elevate the sulfate concentration in the Sheyenne River above the 450 mg l-1 North Dakota sulfate concentration standard for stream class I. Operating the outlets is a wicked problem solving Devils Lake flooding leads to extra discharge and water quality degradation in the Sheyenne River. Solving this problem requires trade of between Devils Lake flood control and the Sheyenne River water quality preservation.

Evaluating Capability of Devils Lake Emergency Outlets in Lowering Lake Water Levels While Controlling flooding Damage to Downstream

NASA Astrophysics Data System (ADS)

Shabani, A.; Zhang, X.

2017-12-01

Devils Lake is an endorheic lake locate in the Red River of the North Basin with a natural outlet at a level of 444.7 meters above the sea level flowing into the Sheyenne River. Historical accumulation of salts has dramatically increased the concentration of salts in the lake, particularly of the sulfates, that are much greater than the surrounding water bodies. Since 1993, the lake water level has risen by nearly 10 meters and caused extensive flooding in the surrounding area, and greatly increased the chance of natural spillage to the Sheyenne River. To mitigate Devils Lake flooding and to prevent its natural spillage, two outlets were constructed at the west and east sides of the lake to drain the water to the Sheyenne River in a controlled fashion. However, pumping water from Devils Lake has degraded water quality of the Sheyenne River. In an earlier study, we coupled Soil and Water Assessment Tools (SWAT) and CE-QUAL-W2 models to investigate the changes of sulfate distribution as the lake water level rises. We found that, while operating the two outlets has lowered Devils Lake water level by 0.7 meter, it has also significantly impaired the Sheyenne River water quality, increasing the Sheyenne River average sulfate concentration from 105 to 585 mg l-1 from 2012 to 2014 In this study, we investigate the impact of the outlets on the Sheyenne River floodplain by coupling SWAT and HEC-RAS model. The SWAT model performed well in simulating daily streamflow in the Sheyenne River with R2>0.56 and ENS > 0.52. The simulated water depths and floodplain by HEC-RAS model for the Sheyenne River agreed well with observations. Operating the outlets from April to October can draw down the Devil Lake water level by 0.45 m, but the drained water would almost double the extension of the Sheyenne River floodplain and elevate the sulfate concentration in the Sheyenne River above the 450 mg l-1 North Dakota sulfate concentration standard for stream class I. Operating the outlets is a wicked problem solving Devils Lake flooding leads to extra discharge and water quality degradation in the Sheyenne River. Solving this problem requires trade of between Devils Lake flood control and the Sheyenne River water quality preservation.

Addition of a Worm Leachate as Source of Humic Substances in the Drinking Water of Broiler Chickens

PubMed Central

Gomez-Rosales, S.; de L. Angeles, M.

2015-01-01

The objective of this research was to evaluate the growth performance, the apparent ileal digestibility of nitrogen and energy, the retention of nutrients and the apparent metabolizable energy corrected to zero nitrogen retention (AMEn) in broiler chickens supplemented with increasing doses of a worm leachate (WL) as a source of humic substances (HS) in the drinking water. In Exp. 1, 140 male broilers were penned individually and assigned to four WL levels (0%, 10%, 20%, and 30%) mixed in the drinking water from 21 to 49 days of age. Water was offered in plastic bottles tied to the cage. In Exp. 2, 600 male broilers from 21 to 49 days of age housed in floor pens were assigned to three levels of WL (0%, 10%, and 20%) mixed in the drinking water. The WL was mixed with tap water in plastic containers connected by plastic tubing to bell drinkers. The results of both experiments were subjected to analysis of variance and polynomial contrasts. In Exp. 1, the daily water consumption was similar among treatments but the consumption of humic, fulvic, and total humic acids increased linearly (p<0.01) as the WL increased in the drinking water. The feed conversion (p<0.01) and the ileal digestibility of energy, the excretion of dry matter and energy, the retention of dry matter, ash and nitrogen and the AMEn showed quadratic responses (p<0.05) relative to the WL levels in drinking water. In Exp. 2, the increasing level of WL in the drinking water had quadratic effects on the final body weight, daily weight gain and feed conversion ratio (p<0.05). The addition of WL as a source of HS in the drinking water had beneficial effects on the growth performance, ileal digestibility of energy, the retention of nutrients as well on the AMEn in broiler chickens; the best results were observed when the WL was mixed at levels of 20% to 30% in the drinking water. PMID:25557817

Addition of a worm leachate as source of humic substances in the drinking water of broiler chickens.

PubMed

Gomez-Rosales, S; de L Angeles, M

2015-02-01

The objective of this research was to evaluate the growth performance, the apparent ileal digestibility of nitrogen and energy, the retention of nutrients and the apparent metabolizable energy corrected to zero nitrogen retention (AMEn) in broiler chickens supplemented with increasing doses of a worm leachate (WL) as a source of humic substances (HS) in the drinking water. In Exp. 1, 140 male broilers were penned individually and assigned to four WL levels (0%, 10%, 20%, and 30%) mixed in the drinking water from 21 to 49 days of age. Water was offered in plastic bottles tied to the cage. In Exp. 2, 600 male broilers from 21 to 49 days of age housed in floor pens were assigned to three levels of WL (0%, 10%, and 20%) mixed in the drinking water. The WL was mixed with tap water in plastic containers connected by plastic tubing to bell drinkers. The results of both experiments were subjected to analysis of variance and polynomial contrasts. In Exp. 1, the daily water consumption was similar among treatments but the consumption of humic, fulvic, and total humic acids increased linearly (p<0.01) as the WL increased in the drinking water. The feed conversion (p<0.01) and the ileal digestibility of energy, the excretion of dry matter and energy, the retention of dry matter, ash and nitrogen and the AMEn showed quadratic responses (p<0.05) relative to the WL levels in drinking water. In Exp. 2, the increasing level of WL in the drinking water had quadratic effects on the final body weight, daily weight gain and feed conversion ratio (p<0.05). The addition of WL as a source of HS in the drinking water had beneficial effects on the growth performance, ileal digestibility of energy, the retention of nutrients as well on the AMEn in broiler chickens; the best results were observed when the WL was mixed at levels of 20% to 30% in the drinking water.

Indole-3-acetic acid modulates phytohormones and polyamines metabolism associated with the tolerance to water stress in white clover.

PubMed

Li, Zhou; Li, Yaping; Zhang, Yan; Cheng, Bizhen; Peng, Yan; Zhang, Xinquan; Ma, Xiao; Huang, Linkai; Yan, Yanhong

2018-06-09

Endogenous hormones and polyamines (PAs) could interact to regulate growth and tolerance to water stress in white clover. The objective of this study was to investigate whether the alteration of endogenous indole-3-acetic acid (IAA) level affected other hormones level and PAs metabolism contributing to the regulation of tolerance to water stress in white clover. Plants were pretreated with IAA or L-2-aminooxy-3-phenylpropionic acid (L-AOPP, the inhibitor of IAA biosynthesis) for 3 days and then subjected to water-sufficient condition and water stress induced by 15% polyethylene glycol 6000 for 8 days in growth chambers. Exogenous application of IAA significantly increased endogenous IAA, gibberellin (GA), abscisic acid (ABA), and polyamine (PAs) levels, but had no effect on cytokinin content under water stress. The increase in endogenous IAA level enhanced PAs anabolism via the improvement of enzyme activities and transcript level of genes including arginine decarboxylase, ornithine decarboxylase, and S-adenosylmethionine decarboxylase. Exogenous application of IAA also affected PAs catabolism, as manifested by an increase in diamine oxidase and a decrease in polyamine oxidase activities and genes expression. More importantly, the IAA deficiency in white clover decreased endogenous hormone levels (GA, ABA, and PAs) and PAs anabolism along with decline in antioxidant defense and osmotic adjustment (OA). On the contrary, exogenous IAA effectively alleviated stress-induced oxidative damage, growth inhibition, water deficit, and leaf senescence through the maintenance of higher chlorophyll content, OA, and antioxidant defense as well as lower transcript levels of senescence marker genes SAG101 and SAG102 in leaves under water stress. These results indicate that IAA-induced the crosstalk between endogenous hormones and PAs could be involved in the improvement of antioxidant defense and OA conferring tolerance to water stress in white clover. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

Metal uptake of tomato and alfalfa plants as affected by water source, salinity, and Cd and Zn levels under greenhouse conditions.

PubMed

Gharaibeh, Mamoun A; Marschner, Bernd; Heinze, Stefanie

2015-12-01

Irrigation with wastewater is a promising option to improve crop yields and to reduce pressure on freshwater sources. However, heavy metal concentrations in wastewater may cause health concerns. A greenhouse pot experiment was conducted in order to determine cadmium (Cd) and zinc (Zn) concentrations in sandy soil and plant tissues of tomato (Lycopersicon esculentum L.) and alfalfa (Medicago sativa L.). A 2 × 2 × 4 × 2 factorial treatment arrangement was utilized. Two water sources, fresh (FW) or treated wastewater (TWW), at two salinity levels (1 and 3 dS m(-1)) containing different levels of Cd and Zn were used. Samples were collected after a 90-day growth period. It was observed that the growth of both plants was depressed at the highest metal level (L3). Metal accumulation in plant parts increased with the increase of metal concentration and salinity in irrigation water. At low salinity, water source was the main factor which controlled metal accumulation, whereas, at high salinity, chloride appeared to be the principal factor controlling metal uptake regardless of water source. Metal translocation from roots to shoots increased in TWW-irrigated plants, even in the controls. Tomatoes accumulated Cd up to and above critical levels safe for human consumption, even though Cd concentration in irrigation water did not exceed the current recommended values. Therefore, food production in sandy soils may well pose a health hazard when irrigated with TWW containing heavy metals. Complexation with dissolved organic compounds (DOC) in TWW may be to be the principal factor responsible for increased metal uptake and transfer at low salinity, thereby increasing the risk of heavy metal contamination of food and forage crops.

Ground-water levels in and pumpage from the alluvial aquifer at Louisville, Kentucky, May 1989-May 1991

USGS Publications Warehouse

Unthank, Michael D.

1995-01-01

Water-level data have been collected in the alluvial aquifer at Louisville, Ky., by the U.S. Geological Survey since 1943. Interpretations of these data are published periodically to update the record and help local officials manage this ground-water supply. Maps and hydrographs are presented on two sheets to aid in the interpretation of water-level changes for the period May 1989-May 1991. The altitude of the water table in the alluvial aquifer has increased as much as 5 feet in some areas during the 2-year period of May 1989-May 1991. Hydrographs for obser- vation wells throughout the alluvial aquifer show that water levels fluctuate seasonally and in response to wet and dry periods; overall, the water- level trend has been upward in recent years. Water levels in the downtown area are affected by the pumping of ground water to heat and cool several buildings in the area. Ground-water contour maps show induced infiltration of water from the Ohio River to the alluvial aquifer in downtown Louisville as a result of the ground-water pumping.

Monitoring of Sparta Aquifer Recovery in Southern Arkansas and Northern Louisiana, 2003-07

USGS Publications Warehouse

Freiwald, David A.; Johnson, Sherrel F.

2007-01-01

Prior to 2004, the Sparta aquifer supplied all water for industrial and municipal uses in Union County, Arkansas, and continues to provide the majority of water for industrial and municipal purposes in the surrounding southern Arkansas counties and northern Louisiana parishes. In Union County, the Sparta aquifer has been used increasingly since development began in the early 1920s, resulting in water-level declines of more than 360 feet (ft) near El Dorado, Arkansas. In addition, water quality in some areas of the Sparta aquifer has degraded with increased withdrawals. In 2002 a study began that measures, through monitoring and reporting of water levels in Sparta aquifer wells throughout the study area in southern Arkansas and northern Louisiana, the impact of conservation and alternative water efforts on water level and water quality. This study provides continuous real-time water-level data at eight USGS wells that are part of a network of 29 monitoring wells and periodically reports results of semi-annual water-quality sampling. Water levels have risen in all eight real-time wells since monitoring began in the summer of 2003, and the Ouachita River Alternative Water Supply Project was completed in September 2004. The largest water-level rises occurred between October 2004 and April 2007 in the Monsanto well (49.0 ft rise) just north of El Dorado, and the Welcome Center well (36.1 ft rise) southeast of El Dorado. Twelve wells were sampled semi-annually for specific conductance and chloride concentration. Average specific conductance from individual wells ranges from 216 in the northwest to 1,157 uS/cm in the southeast and average chloride concentration ranges from 3.2 to 214 mg/L.

Water-Level Data for the Albuquerque Basin and Adjacent Areas, Central New Mexico, Period of Record Through September 30, 2007

USGS Publications Warehouse

Beman, Joseph E.

2008-01-01

The Albuquerque Basin, located in central New Mexico, is about 100 miles long and 25 to 40 miles wide. The basin is defined as the extent of consolidated and unconsolidated deposits of Tertiary and Quaternary age that encompass the structural Rio Grande Rift within the basin. Drinking-water supplies throughout the basin are currently (2007) obtained solely from ground-water resources. An increase of about 20 percent in the population from 1990 to 2000 also resulted in an increased demand for water. A network of wells was established to monitor changes in ground-water levels throughout the basin from April 1982 through September 1983. This network consisted of 6 wells with analog-to-digital recorders and 27 wells where water levels were measured monthly in 1983. Currently (2007), the network consists of 131 wells and piezometers. This report presents water-level data collected by U.S. Geological Survey personnel at 131 sites through water-year 2007. Data from five sites (Sites 9, 10, 31, 71 and 78) were not measured during the 2007 water-year, but are included in this report because recent data are useful for comparison and (or) data have been collected that will be included in the water-year 2008 report.

Subseasonal to Seasonal Predictions of U.S. West Coast High Water Levels

NASA Astrophysics Data System (ADS)

Khouakhi, A.; Villarini, G.; Zhang, W.; Slater, L. J.

2017-12-01

Extreme sea levels pose a significant threat to coastal communities, ecosystems, and assets, as they are conducive to coastal flooding, coastal erosion and inland salt-water intrusion. As sea levels continue to rise, these sea level extremes - including occasional minor coastal flooding experienced during high tide (nuisance floods) - are of concern. Extreme sea levels are increasing at many locations around the globe and have been attributed largely to rising mean sea levels associated with intra-seasonal to interannual climate processes such as the El Niño-Southern Oscillation (ENSO). Here, intra-seasonal to seasonal probabilistic forecasts of high water levels are computed at the Toke Point tide gage station on the US west coast. We first identify the main climate drivers that are responsible for high water levels and examine their predictability using General Circulation Models (GCMs) from the North American Multi-Model Ensemble (NMME). These drivers are then used to develop a probabilistic framework for the seasonal forecasting of high water levels. We focus on the climate controls on the frequency of high water levels using the number of exceedances above the 99.5th percentile and above the nuisance flood level established by the National Weather Service. Our findings indicate good forecast skill at the shortest lead time, with the skill that decreases as we increase the lead time. In general, these models aptly capture the year-to-year variability in the observational records.

Floodplains within reservoirs promote earlier spawning of white crappies Pomoxis annularis

USGS Publications Warehouse

Miranda, Leandro E.; Dagel, Jonah D.; Kaczka, Levi J.; Mower, Ethan; Wigen, S. L.

2015-01-01

Reservoirs impounded over floodplain rivers are unique because they may include within their upper reaches extensive shallow water stored over preexistent floodplains. Because of their relatively flat topography and riverine origin, floodplains in the upper reaches of reservoirs provide broad expanses of vegetation within a narrow range of reservoir water levels. Elsewhere in the reservoir, topography creates a band of shallow water along the contour of the reservoir where vegetation often does not grow. Thus, as water levels rise, floodplains may be the first vegetated habitats inundated within the reservoir. We hypothesized that shallow water in reservoir floodplains would attract spawning white crappies Pomoxis annularis earlier than reservoir embayments. Crappie relative abundance over five years in floodplains and embayments of four reservoirs increased as spawning season approached, peaked, and decreased as fish exited shallow water. Relative abundance peaked earlier in floodplains than embayments, and the difference was magnified with higher water levels. Early access to suitable spawning habitat promotes earlier spawning and may increase population fitness. Recognition of the importance of reservoir floodplains, an understanding of how reservoir water levels can be managed to provide timely connectivity to floodplains, and conservation of reservoir floodplains may be focal points of environmental management in reservoirs.

Water-Level Data for the Albuquerque Basin and Adjacent Areas, Central New Mexico, Period of Record Through September 30, 2008

USGS Publications Warehouse

Beman, Joseph E.

2009-01-01

The Albuquerque Basin, located in central New Mexico, is about 100 miles long and 25 to 40 miles wide. The basin is defined as the extent of consolidated and unconsolidated deposits of Tertiary and Quaternary age that encompass the structural Rio Grande Rift within the basin. Drinking-water supplies throughout the basin are currently (2008) obtained soley from ground-water resources. An increase of about 20 percent in the population from 1990 to 2000 also resulted in an increased demand for water. A network of wells was established to monitor changes in ground-water levels throughout the basin from April 1982 through September 1983. This network consisted of 6 wells with analog-to-digital recorders and 27 wells where water levels were measured monthly in 1983. Currently (2008), the network consists of 144 wells and piezometers. This report presents water-level data collected by U.S. Geological Survey personnel at 125 sites through water-year 2008. In addition, data from 19 wells (Sites 127-30, 132-134, 136, 138-142 and 144-149) owned, maintained, and measured by Sandia National Laboratories are presented in this report.

Potentiometric surface of the Ozark aquifer in northern Arkansas, 2010

USGS Publications Warehouse

Czarnecki, John B.; Pugh, Aaron L.; Blackstock, Joshua M.

2014-01-01

The Ozark aquifer in northern Arkansas is composed of dolomite, limestone, sandstone, and shale of Late Cambrian to Middle Devonian age and ranges in thickness from approximately 1,100 feet to more than 4,000 feet. Hydrologically, the aquifer is complex, characterized by discrete and discontinuous flow components with large variations in permeability. The potentiometric-surface map, based on 56 well and 5 spring water-level measurements made in 2010 in Arkansas and Missouri, has a maximum water-level altitude measurement of 1,174 feet in Carroll County and a minimum water-level altitude measurement of 120 feet in Randolph County. Regionally, the flow within the aquifer is to the south and southeast in the eastern and central part of the study area and to the west, northwest, and north in the western part of the study area. Water-level altitudes changed 0.5 feet or less in 31 out of 56 wells measured between 2007 and 2010. Despite rapidly increasing population within the study area, the increase appears to have minimal effect on groundwater levels, although the effect may have been minimized by the development and use of surface-water distribution infrastructure, suggesting that most of the incoming populations are fulfilling their water needs from surface-water sources. The conversion of some users from groundwater to surface water may be allowing water levels in some wells to recover (rise) or decline at a slower rate in some areas such as in Benton, Carroll, and Washington Counties.

Hydration level is an internal variable for computing motivation to obtain water rewards in monkeys.

PubMed

Minamimoto, Takafumi; Yamada, Hiroshi; Hori, Yukiko; Suhara, Tetsuya

2012-05-01

In the process of motivation to engage in a behavior, valuation of the expected outcome is comprised of not only external variables (i.e., incentives) but also internal variables (i.e., drive). However, the exact neural mechanism that integrates these variables for the computation of motivational value remains unclear. Besides, the signal of physiological needs, which serves as the primary internal variable for this computation, remains to be identified. Concerning fluid rewards, the osmolality level, one of the physiological indices for the level of thirst, may be an internal variable for valuation, since an increase in the osmolality level induces drinking behavior. Here, to examine the relationship between osmolality and the motivational value of a water reward, we repeatedly measured the blood osmolality level, while 2 monkeys continuously performed an instrumental task until they spontaneously stopped. We found that, as the total amount of water earned increased, the osmolality level progressively decreased (i.e., the hydration level increased) in an individual-dependent manner. There was a significant negative correlation between the error rate of the task (the proportion of trials with low motivation) and the osmolality level. We also found that the increase in the error rate with reward accumulation can be well explained by a formula describing the changes in the osmolality level. These results provide a biologically supported computational formula for the motivational value of a water reward that depends on the hydration level, enabling us to identify the neural mechanism that integrates internal and external variables.

On the derivation of specific yield and soil water retention characteristics in peatlands from rainfall, microrelief and water level data - Theory and Practice

NASA Astrophysics Data System (ADS)

Dettmann, Ullrich; Bechtold, Michel

2016-04-01

Water level depth is one of the crucial state variables controlling the biogeochemical processes in peatlands. For flat soil surfaces, water level depth dynamics as response to boundary fluxes are primarily controlled by the water retention characteristics of the soil in and above the range of the water level fluctuations. For changing water levels, the difference of the integrals of two soil moisture profiles (ΔAsoil), of a lower and a upper water level, is equal to the amount of water received or released by the soil. Dividing ΔAsoil by the water level change, results into a variable that is known as specific yield (Sy). For water level changes approaching the soil surface, changes in soil water storage are small due to the thin unsaturated zone that remains. Consequentially, Sy values approach zero with an abrupt transition to 1 in case of inundation. However, on contrary, observed water level rises due to precipitation events at various locations showed increasing Sy values for water level changes at shallow depths (Sy = precipitation/water level change; Logsdon et al., 2010). The increase of Sy values can be attributed in large parts to the influence of the microrelief on water level changes in these wet landscapes that are characterized by a mosaic of inundated and non-inundated areas. Consequentially, water level changes are dampened by partial inundation. In this situation, total Sy is composed of a spatially-integrated below ground and above ground contribution. We provide a general one-dimensional expression that correctly represents the effect of a microrelief on the total Sy. The one-dimensional expression can be applied for any soil hydraulic parameterizations and soil surface elevation frequency distributions. We demonstrate that Sy is influenced by the microrelief not only when surface storage directly contributes to Sy by (partial) inundation but also when water levels are lower than the minimum surface elevation. With the derived one-dimensional expression we developed a novel approach for the in situ determination of soil water retention characteristics that is applicable to shallow groundwater systems. Our approach is built on two assumptions: i) for shallow groundwater systems with medium- to high conductive soils the soil moisture profile is always close to hydrostatic equilibrium and ii) over short time periods differences in total water storage due to lateral fluxes are negligible. Given these assumptions, the height of a water level rise due to a precipitation event mainly depends on the soil water retention characteristics, the precipitation amount, the initial water level depth and, if present, the microrelief. We use this dependency to determine water retention characteristics (van Genuchten parameter) by Bayesian inversion. Our results demonstrate that observations of water level rises, caused by precipitation events, contain sufficient information to constrain the water retention characteristics around two dip wells in a Sphagnum bog to plausible ranges. We discuss the possible biases that come along with our approach and point out the research that is needed to quantify their significance.

Response in the trophic state of stratified lakes to changes in hydrology and water level: potential effects of climate change

USGS Publications Warehouse

Robertson, Dale M.; Rose, William J.

2011-01-01

To determine how climate-induced changes in hydrology and water level may affect the trophic state (productivity) of stratified lakes, two relatively pristine dimictic temperate lakes in Wisconsin, USA, were examined. Both are closed-basin lakes that experience changes in water level and degradation in water quality during periods of high water. One, a seepage lake with no inlets or outlets, has a small drainage basin and hydrology dominated by precipitation and groundwater exchange causing small changes in water and phosphorus (P) loading, which resulted in small changes in water level, P concentrations, and productivity. The other, a terminal lake with inlets but no outlets, has a large drainage basin and hydrology dominated by runoff causing large changes in water and P loading, which resulted in large changes in water level, P concentrations, and productivity. Eutrophication models accurately predicted the effects of changes in hydrology, P loading, and water level on their trophic state. If climate changes, larger changes in hydrology and water levels than previously observed could occur. If this causes increased water and P loading, stratified (dimictic and monomictic) lakes are expected to experience higher water levels and become more eutrophic, especially those with large developed drainage basins.

Water level response to hydropower development in the upper Mekong River.

PubMed

Li, Shaojuan; He, Daming

2008-05-01

Environmental changes and their transboundary influences on the Mekong watercourse system have been an international research focus in recent years, but the opinions and results related to the impacts of upper Mekong River dams are quite different. In this paper, based on the records of water levels from 1960 to 2003 at three mainstream sites in the upper Mekong River, a quantitative examination has been undertaken into characteristics of the mainstream water-level process at multiple timescales and its response to cascade development. The major results are: i) Annual mean, wet period mean, and the mean water levels during the period between March and April (PBMA period) exhibit a significant increasing trend at Jiuzhou and Yunjinghong sites, which are influenced by large-scale factors such as climate change and solar activity. ii) The interdecadal and interannual variations of annual mean, annual maximum, and wet period mean water levels at three sites show similar features during the dam construction period. iii) The interdecadal variations of PBMA period water level show a gradual increase at Gajiu and Yunjinghong sites but a falling trend at Jiuzhou; these trends confirm that there is some regulation on the flow in the dry season caused by the two existing dams. iv) The downstream effects of the present dams on water levels are very limited at the annual mean and wet season mean levels, not apparent at the monthly and yearly timescales, and relatively significant at daily and hourly timescales.

Response of walleye and yellow perch to water-level fluctuations in glacial lakes

USGS Publications Warehouse

Dembkowski, D.J.; Chipps, Steven R.; Blackwell, B. G.

2014-01-01

The influence of water levels on population characteristics of yellow perch, Perca flavescens (Mitchill), and walleye, Sander vitreus (Mitchill), was evaluated across a range of glacial lakes in north-eastern South Dakota, USA. Results showed that natural variation in water levels had an important influence on frequently measured fish population characteristics. Yellow perch abundance was significantly (P<0.10) greater during elevated water levels. Yellow perch size structure, as indexed by the proportional size distribution of quality- and preferred-length fish (PSD and PSD-P), was significantly greater during low-water years, as was walleye PSD. Mean relative weight of walleye increased significantly during high-water periods. The dynamic and unpredictable nature of water-level fluctuations in glacial lakes ultimately adds complexity to management of these systems.

Geochemistry and geohydrology of the West Decker and Big Sky coal-mining areas, southeastern Montana

USGS Publications Warehouse

Davis, R.E.

1984-01-01

In the West Decker Mine area, water levels west of the mine at post-mining equilibrium may be almost 12 feet higher than pre-mining levels. Dissolved-solids concentration in water from coal aquifers is about 1,400 milligrams per liter and from mine spoils is about 2,500 milligrams per liter. About 13 years will be required for ground water moving at an average velocity of 2 feet per day to flow from the spoils to the Tongue River Reservoir. The increase in dissolved-solids load to the reservoir due to mining will be less than 1 percent. In the Big Sky Mine area, water levels at post-mining equilibrium will closely resemble pre-mining levels. Dissolved-solids concentration in water from coal aquifers is about 2,700 milligrams per liter and from spoils is about 3,700 milligrams per liter. About 36 to 60 years will be required for ground water moving at an average velocity of 1.2 feet per day to flow from the spoils to Rosebud Creek. The average annual increase in dissolved-solids load to the creek due to mining will be about 2 percent, although a greater increase probably will occur during summer months when flow in the creek is low. (USGS)

Hydrologic analysis of the High Plains aquifer system in Box Butte County, Nebraska

USGS Publications Warehouse

Pettijohn, R.A.; Chen, Hsiu-Hsiung

1984-01-01

During the past 40 years, pumpage of ground water for irrigation from the High Plains aquifer system underlying Box Butte County, Nebraska, has resulted in a steady decline of water levels. Consequently, a digital model of the aquifer system was constructed to evaluate various water-management alternatives. The hydraulic conductivity of the aquifer system ranges from 6 to 60 feet per day; the specific yield ranges from 12 to 21 percent; and natural recharge ranges from 0.06 to 4.33 inches annually. Predevelopment saturated thickness (1938) ranged from 190 to 510 feet. Water pumped in 1980 was estimated at 104,000 acre-feet from an estimated recoverable volume of 34.4 million acre-feet in the aquifer system. Results from model simulation predict that the area of water-level declines of 10 feet or more will increase from 336 square miles (1981) to 630 square miles by 1991 if pumpage is increased at the maximum annual rate experienced for the period 1972-81. Maximum water-level declines would increase from 50 feet (1981) to 79 feet (1991). However, pumpage rates held at the 1981 level (no further development) would limit the decline area of 10 feet or more to 530 square miles by 1991 and the maximum decline to 63 feet. (USGS)

Preliminary investigation of the effects of sea-level rise on groundwater levels in New Haven, Connecticut

USGS Publications Warehouse

Bjerklie, David M.; Mullaney, John R.; Stone, Janet R.; Skinner, Brian J.; Ramlow, Matthew A.

2012-01-01

Global sea level rose about 0.56 feet (ft) (170 millimeters (mm)) during the 20th century. Since the 1960s, sea level has risen at Bridgeport, Connecticut, about 0.38 ft (115 mm), at a rate of 0.008 ft (2.56 mm + or - 0.58 mm) per year. With regional subsidence, and with predicted global climate change, sea level is expected to continue to rise along the northeast coast of the United States through the 21st century. Increasing sea levels will cause groundwater levels in coastal areas to rise in order to adjust to the new conditions. Some regional climate models predict wetter climate in the northeastern United States under some scenarios. Scenarios for the resulting higher groundwater levels have the potential to inundate underground infrastructure in lowlying coastal cities. New Haven is a coastal city in Connecticut surrounded and bisected by tidally affected waters. Monitoring of water levels in wells in New Haven from August 2009 to July 2010 indicates the complex effects of urban influence on groundwater levels. The response of groundwater levels to recharge and season varied considerably from well to well. Groundwater temperatures varied seasonally, but were warmer than what was typical for Connecticut, and they seem to reflect the influence of the urban setting, including the effects of conduits for underground utilities. Specific conductance was elevated in many of the wells, indicating the influence of urban activities or seawater in Long Island Sound. A preliminary steady-state model of groundwater flow for part of New Haven was constructed using MODFLOW to simulate current groundwater levels (2009-2010) and future groundwater levels based on scenarios with a rise of 3 ft (0.91 meters (m)) in sea level, which is predicted for the end of the 21st century. An additional simulation was run assuming a 3-ft rise in sea level combined with a 12-percent increase in groundwater recharge. The model was constructed from existing hydrogeologic information for the New Haven area and from new information on groundwater levels collected during October 2009-June 2010. For the scenario with a 3-ft rise in sea level and no increase in recharge, simulated groundwater levels near the coast rose 3 ft; this increased water level tapered off toward a discharge area at the only nontidal stream in the study area. Simulated stream discharge increased at the nontidal stream because of the increased gradient. Although groundwater levels rose, the simulated difference between the groundwater levels in the aquifer and the increased sea level declined, indicating that the depth to the interface between freshwater and saltwater may possibly decline. Simulated water levels were affected by rise in sea level even in areas where the water table was at 17-24 ft (5.2-7.3 m) above current (2011) sea level. For the scenario with increased recharge, simulated groundwater levels were as much as an additional foot higher at some locations in the study area. The results of this preliminary investigation indicate that groundwater levels in coastal areas can be expected to rise and may rise higher if groundwater recharge also increases. This finding has implications for the disposal of stormwater through infiltration, a low-impact development practice designed to improve water quality and reduce overland peak discharge. Other implications include increased risk of basement flooding and increased groundwater seepage into underground sewer pipes and utility corridors in some areas. These implications will present engineering challenges to New Haven and Yale University. The preliminary model developed for this study can be the starting point for further simulation of future alternative scenarios for sea-level rise and recharge. Further simulations could identify those areas of New Haven where infrastructure may be at greatest risk from rising levels of groundwater. The simulations described in this report have limitations due to the preliminary scope of the work. Approaches to improve simulations include but are not limited to incorporating: * The variable density of seawater into the model in order to understand the current and future location of the interface between freshwater and saltwater; * Collection of additional data in order to better resolve temporal and spatial patterns in water levels in the aquifer; * Improved estimates of recharge through direct and indirect measurements of freshwater discharge from the study area; and * Transient simulations for greater understanding of the amount of time required for water levels and the position of the interface between freshwater and saltwater to adjust to changes in sea level and recharge.

Dose-effect relationship between drinking water fluoride levels and damage to liver and kidney functions in children.

PubMed

Xiong, Xianzhi; Liu, Junling; He, Weihong; Xia, Tao; He, Ping; Chen, Xuemin; Yang, Kedi; Wang, Aiguo

2007-01-01

Although a dose-effect relationship between water fluoride levels and damage to liver and kidney functions in animals has been reported, it was not demonstrated in humans. To evaluate the effects of drinking water fluoride levels on the liver and kidney functions in children with and without dental fluorosis, we identified 210 children who were divided into seven groups with 30 each based on different drinking water fluoride levels in the same residential area. We found that the fluoride levels in serum and urine of these children increased as the levels of drinking water fluoride increased. There were no significant differences in the levels of total protein (TP), albumin (ALB), aspartate transamine (AST), and alanine transamine (ALT) in serum among these groups. However, the activities of serum lactic dehydrogenase (LDH), urine N-acetyl-beta-glucosaminidase (NAG), and urine gamma-glutamyl transpeptidase (gamma-GT) in children with dental fluorosis and having water fluoride of 2.15-2.96 mg/L and in children having water fluoride of 3.15-5.69 mg/L regardless of dental fluorosis were significantly higher than children exposed to water fluoride of 0.61-0.87 mg/L in a dose-response manner. In contrast to children with dental fluorosis and having water fluoride of 2.15-2.96 and 3.10-5.69 mg/L, serum LDH activity of children without dental fluorosis but exposed to the same levels of water fluoride as those with dental fluorosis were also markedly lower, but the activities of NAG and gamma-GT in their urine were not. Therefore, our results suggest that drinking water fluoride levels over 2.0mg/L can cause damage to liver and kidney functions in children and that the dental fluorosis was independent of damage to the liver but not the kidney. Further studies on the mechanisms and significance underlying damage to the liver without dental fluorosis in the exposed children are warranted.

Developmental toxicity evaluations of whole mixtures of disinfection by-products using concentrated drinking water in rats: gestational and lactational effects of sulfate and sodium.

PubMed

Narotsky, Michael G; Pressman, Jonathan G; Miltner, Richard J; Speth, Thomas F; Teuschler, Linda K; Rice, Glenn E; Richardson, Susan D; Best, Deborah S; McDonald, Anthony; Hunter, E Sidney; Simmons, Jane Ellen

2012-06-01

A developmental toxicity bioassay was used in three experiments to evaluate water concentrates for suitability in multigenerational studies. First, chlorinated water was concentrated 135-fold by reverse osmosis; select lost disinfection by-products were spiked back. Concentrate was provided as drinking water to Sprague-Dawley and F344 rats from gestation day 6 to postnatal day 6. Maternal serum levels of luteinizing hormone on gestation day 10 were unaffected by treatment for both strains. Treated dams had increased water consumption, and increased incidences of polyuria, diarrhea, and (in Sprague-Dawley rats) red perinasal staining. Pup weights were reduced. An increased incidence of eye defects was seen in F344 litters. Chemical analysis of the concentrate revealed high sodium (6.6 g/l) and sulfate (10.4 g/l) levels. To confirm that these chemicals caused polyuria and osmotic diarrhea, respectively, Na₂SO₄ (5-20 g/l) or NaCl (16.5 g/l) was provided to rats in drinking water. Water consumption was increased at 5- and 10-g Na₂SO₄/l and with NaCl. Pup weights were reduced at 20-g Na₂SO₄/l. Dose-related incidences and severity of polyuria and diarrhea occurred in Na₂SO₄-treated rats; perinasal staining was seen at 20 g/l. NaCl caused polyuria and perinasal staining, but not diarrhea. Subsequently, water was concentrated ∼120-fold and sulfate levels were reduced by barium hydroxide before chlorination, yielding lower sodium (≤1.5 g/l) and sulfate (≤2.1 g/l) levels. Treatment resulted in increased water consumption, but pup weight and survival were unaffected. There were no treatment-related clinical findings, indicating that mixtures produced by the second method are suitable for multigenerational testing. Published 2012 by Wiley Periodicals, Inc.

Indirect effects of climate change on zinc cycling in sediments: The role of changing water levels.

PubMed

Nedrich, Sara M; Burton, G Allen

2017-09-01

Increased variability in lake and river water levels associated with changing climate could impact the fate and effects of metals in redox-sensitive sediments through the alteration of microbial communities and of acid-base and redox chemistry. The objective of the present study was to determine the influence of water level fluctuation on metal speciation in porewater and predict environmental risk to high-carbonate systems. Using experimental microcosms with sediments collected from 4 metal-contaminated coastal freshwater wetlands in Michigan, USA, we conducted water level fluctuation experiments. Porewater and sediment metals (Ca, Cu, Fe, Mg, Mn, Ni, Zn) and important metal binding phases (iron-oxide speciation, acid-volatile sulfide) were quantified. In a short-term drying (seiche) experiment, there were decreases in all porewater metals after inundation of saturated sediments. During a drought experiment, re-inundation of oxidized sediments increased porewater Cu, Zn, Mg, Ca for most sites. Porewater Zn increased after inundation to levels exceeding the US Environmental Protection Agency threshold for chronic toxicity. These data show that the dissolution of metal carbonates and metal sulfates contributes to metal release after re-flooding and indicate that we might expect increased ecological risk to organisms present in drought-sensitive regions where altered hydroperiods are likely to increase metal bioavailability. Environ Toxicol Chem 2017;36:2456-2464. © 2017 SETAC. © 2017 SETAC.

Effects of climate change on water quality in the Yaquina ...

EPA Pesticide Factsheets

As part of a larger study to examine the effect of climate change (CC) on estuarine resources, we simulated the effect of rising sea level, alterations in river discharge, and increasing atmospheric temperatures on water quality in the Yaquina Estuary. Due to uncertainty in the effects of climate change, initial model simulations were performed for different steady river discharge rates that span the historical range in inflow, and for a range of increases in sea level and atmospheric temperature. Model simulations suggest that in the central portion of the estuary (19 km from mouth), a 60-cm increase in sea level will result in a 2-3 psu change in salinity across a broad range of river discharges. For the oligohaline portion of the estuary, salinity increases associated with a rise in sea level of 60 cm are only apparent at low river discharge rates (< 50 m3 s-1). Simulations suggest that the water temperatures near the mouth of the estuary will decrease due to rising sea level, while water temperatures in upriver portions of the estuary will increase due to rising atmospheric temperatures. We present results which demonstrate how the interaction of changes in river discharge, rising sea level, and atmospheric temperature associated with climate change produce non-linear patterns in the response of estuarine salinity and temperature, which vary with location inside the estuary and season. We also will discuss the importance of presenting results in a mann

Effect of protein and glycerol concentration on the mechanical, optical, and water vapor barrier properties of canola protein isolate-based edible films.

PubMed

Chang, Chang; Nickerson, Michael T

2015-01-01

Biodegradable edible films prepared using proteins are both economically and environmentally important to the food packaging industry relative to traditional petroleum-derived synthetic materials. In the present study, the mechanical and water vapor barrier properties of casted canola protein isolate edible films were investigated as a function of protein (5.0% and 7.5%) and glycerol (30%, 35%, 40%, 45%, and 50%) content. Specifically, tensile strength and elongation, elastic modulus, puncture strength and deformation, opacity, and water vapor permeability were measured. Results indicated that tensile strength, puncture strength, and elastic modulus decreased, while tensile elongation and puncture deformation values increased as glycerol concentration increased for both 5.0% and 7.5% canola protein isolate films. Furthermore, tensile strength, puncture strength, and elastic modulus values were found to increase at higher protein concentrations within the canola protein isolate films, whereas puncture deformation values decreased. Tensile elongation was found to be similar for both canola protein isolate protein levels. Canola protein isolate films became more transparent with increasing of glycerol concentration and decreasing of canola protein isolate concentration. Water vapor permeability value was also found to increase with increasing glycerol and protein contents. Overall, results indicated that canola protein isolate films were less brittle, more malleable and transparent, and had greater water vapor permeability at higher glycerol levels. However, as protein level increased, canola protein isolate films were more brittle, less malleable and more opaque, and also had increased water vapor permeability. © The Author(s) 2013 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Habitat Selection by African Buffalo (Syncerus caffer) in Response to Landscape-Level Fluctuations in Water Availability on Two Temporal Scales

PubMed Central

Bennitt, Emily; Bonyongo, Mpaphi Casper; Harris, Stephen

2014-01-01

Seasonal fluctuations in water availability cause predictable changes in the profitability of habitats in tropical ecosystems, and animals evolve adaptive behavioural and spatial responses to these fluctuations. However, stochastic changes in the distribution and abundance of surface water between years can alter resource availability at a landscape scale, causing shifts in animal behaviour. In the Okavango Delta, Botswana, a flood-pulsed ecosystem, the volume of water entering the system doubled between 2008 and 2009, creating a sudden change in the landscape. We used African buffalo (Syncerus caffer) to test the hypotheses that seasonal habitat selection would be related to water availability, that increased floodwater levels would decrease forage abundance and affect habitat selection, and that this would decrease buffalo resting time, reduce reproductive success and decrease body condition. Buffalo selected contrasting seasonal habitats, using habitats far from permanent water during the rainy season and seasonally-flooded habitats close to permanent water during the early and late flood seasons. The 2009 water increase reduced forage availability in seasonally-flooded habitats, removing a resource buffer used by the buffalo during the late flood season, when resources were most limited. In response, buffalo used drier habitats in 2009, although there was no significant change in the time spent moving or resting, or daily distance moved. While their reproductive success decreased in 2009, body condition increased. A protracted period of high water levels could prove detrimental to herbivores, especially to smaller-bodied species that require high quality forage. Stochastic annual fluctuations in water levels, predicted to increase as a result of anthropogenically-induced climate change, are likely to have substantial impacts on the functioning of water-driven tropical ecosystems, affecting environmental conditions within protected areas. Buffer zones around critical seasonal resources are essential to allow animals to engage in compensatory behavioural and spatial mechanisms in response to changing environmental conditions. PMID:24983377

Habitat selection by African buffalo (Syncerus caffer) in response to landscape-level fluctuations in water availability on two temporal scales.

PubMed

Bennitt, Emily; Bonyongo, Mpaphi Casper; Harris, Stephen

2014-01-01

Seasonal fluctuations in water availability cause predictable changes in the profitability of habitats in tropical ecosystems, and animals evolve adaptive behavioural and spatial responses to these fluctuations. However, stochastic changes in the distribution and abundance of surface water between years can alter resource availability at a landscape scale, causing shifts in animal behaviour. In the Okavango Delta, Botswana, a flood-pulsed ecosystem, the volume of water entering the system doubled between 2008 and 2009, creating a sudden change in the landscape. We used African buffalo (Syncerus caffer) to test the hypotheses that seasonal habitat selection would be related to water availability, that increased floodwater levels would decrease forage abundance and affect habitat selection, and that this would decrease buffalo resting time, reduce reproductive success and decrease body condition. Buffalo selected contrasting seasonal habitats, using habitats far from permanent water during the rainy season and seasonally-flooded habitats close to permanent water during the early and late flood seasons. The 2009 water increase reduced forage availability in seasonally-flooded habitats, removing a resource buffer used by the buffalo during the late flood season, when resources were most limited. In response, buffalo used drier habitats in 2009, although there was no significant change in the time spent moving or resting, or daily distance moved. While their reproductive success decreased in 2009, body condition increased. A protracted period of high water levels could prove detrimental to herbivores, especially to smaller-bodied species that require high quality forage. Stochastic annual fluctuations in water levels, predicted to increase as a result of anthropogenically-induced climate change, are likely to have substantial impacts on the functioning of water-driven tropical ecosystems, affecting environmental conditions within protected areas. Buffer zones around critical seasonal resources are essential to allow animals to engage in compensatory behavioural and spatial mechanisms in response to changing environmental conditions.

The role of leptin and ghrelin in appetite regulation in the Australian Spinifex hopping mouse, Notomys alexis, during long-term water deprivation.

PubMed

Donald, John A; Hamid, Noor Khalidah Abdul; McLeod, Janet L

2017-04-01

Water deprivation of the Spinifex hopping mouse, Notomys alexis, induced a biphasic pattern of food intake with an initial hypophagia that was followed by an increased, and then sustained food intake. The mice lost approximately 20% of their body mass and there was a loss of white adipose tissue. Stomach ghrelin mRNA was significantly higher at day 2 of water deprivation but then returned to the same levels as water-replete (day 0) mice for the duration of the experiment. Plasma ghrelin was unaffected by water deprivation except at day 10 where it was significantly increased. Plasma leptin levels decreased at day 2 and day 5 of water deprivation, and then increased significantly by the end of the water deprivation period. Water deprivation caused a significant decrease in skeletal muscle leptin mRNA expression at days 2 and 5, but then it returned to day 0 levels by day 29. In the hypothalamus, water deprivation caused a significant up-regulation in both ghrelin and neuropeptide Y mRNA expression, respectively. In contrast, hypothalamic GHSR1a mRNA expression was significantly down-regulated. A significant increase in LepRb mRNA expression was observed at days 17 and 29 of water deprivation. This study demonstrated that the sustained food intake in N. alexis during water deprivation was uncoupled from peripheral appetite-regulating signals, and that the hypothalamus appears to play an important role in regulating food intake; this may contribute to the maintenance of fluid balance in the absence of free water. Copyright © 2016 Elsevier Inc. All rights reserved.

Long-term rise of the Water Table in the Northeast US: Climate Variability, Land-Use Change, or Angry Beavers?

NASA Astrophysics Data System (ADS)

Boutt, D. F.

2011-12-01

The scientific evidence that humans are directly influencing the Earth's natural climate is increasingly compelling. Numerous studies suggest that climate change will lead to changes in the seasonality of surface water availability thereby increasing the need for groundwater development to offset those shortages. Research suggests that the Northeast region of the U.S. is experiencing significant changes to its' natural climate and hydrologic systems. Previous analysis of a long-term regional compilation of the water table response to the last 60 years of climate variability in New England documented a wide range of variability. The investigation evaluated the physical mechanisms, natural variability and response of aquifers in New England using 100 long term groundwater monitoring stations with 20 or more years of data coupled with 67 stream gages, 75 precipitation stations, and 43 temperature stations. Groundwater trends were calculated as normalized anomalies and analyzed with respect to regional compiled precipitation, temperature, and streamflow anomalies to understand the sensitivity of the aquifer systems to change. Interestingly, a trend and regression analysis demonstrate that water level fluctuations are producing statistically significant results with increasing water levels over at least the past thirty years at most (80 out of 100) well sites. In this contribution we investigate the causal mechanisms behind the observed ground water level trends using site-by-site land-use change assessments, cluster analysis, and spatial analysis of beaver populations (a possible proxy for beaver activity). Regionally, average annual precipitation has been slightly increasing since 1900, with 95% of the stations having statistically significant positive trends. Despite this, no correlation is observed between the magnitude of the annual precipitation trends and the magnitude of the groundwater level changes. Land-use change throughout the region has primarily taken place in and around existing urban centers with an overall increase in the percentage of forested land. Individual analysis of well sites in areas with documented land-use change from agriculture and forested land cover to urban land use suggests a positive correlation with increasing water levels. Recently, beaver populations been begun to rise that has led to local increases in wetland areas. These regions also show a high positive correlation to the magnitude of water table rise. Local factors such as land-use change and beaver activity appear to overprint and mask the impact of consistent increases in annual precipitation. Rising water tables have major implications for not only water management but also the agriculture, forestry, fishing, and tourism industries as they all depend on the quantity and quality of water resources of the region.

Potential Effects of Climate Change on the Water Level, Flora and Macro-fauna of a Large Neotropical Wetland

PubMed Central

Úbeda, Bárbara; Di Giacomo, Adrian S.; Neiff, Juan José; Loiselle, Steven A.; Guadalupe Poi, Alicia S.; Gálvez, José Ángel; Casco, Silvina; Cózar, Andrés

2013-01-01

Possible consequences of climate change in one of the world’s largest wetlands (Ibera, Argentina) were analysed using a multi-scale approach. Climate projections coupled to hydrological models were used to analyse variability in wetland water level throughout the current century. Two potential scenarios of greenhouse gas emissions were explored, both resulting in an increase in the inter-annual fluctuations of the water level. In the scenario with higher emissions, projections also showed a long-term negative trend in water-level. To explore the possible response of biota to such water-level changes, species-area relationships of flora and aerial censuses of macro-fauna were analysed during an extraordinary dry period. Plant species richness at the basin scale was found to be highly resistant to hydrological changes, as the large dimension of the wetland acts to buffer against the water-level variations. However, local diversity decreased significantly with low water levels, leading to the loss of ecosystem resilience to additional stressors. The analysis of macro-fauna populations suggested that wetland provides refuge, in low water periods, for the animals with high dispersal ability (aquatic and migratory birds). On the contrary, the abundance of animals with low dispersal ability (mainly herbivorous species) was negatively impacted in low water periods, probably because they are required to search for alternative resources beyond the wetland borders. This period of resource scarcity was also related to increased mortality of large mammals (e.g. marsh deer) around water bodies with high anthropogenic enrichment and cyanobacteria dominance. The synergy between recurrent climatic fluctuations and additional stressors (i.e. biological invasions, eutrophication) presents an important challenge to the conservation of neotropical wetlands in the coming decades. PMID:23874446

Potential effects of climate change on the water level, flora and macro-fauna of a large neotropical wetland.

PubMed

Úbeda, Bárbara; Di Giacomo, Adrian S; Neiff, Juan José; Loiselle, Steven A; Poi, Alicia S Guadalupe; Gálvez, José Ángel; Casco, Silvina; Cózar, Andrés

2013-01-01

Possible consequences of climate change in one of the world's largest wetlands (Ibera, Argentina) were analysed using a multi-scale approach. Climate projections coupled to hydrological models were used to analyse variability in wetland water level throughout the current century. Two potential scenarios of greenhouse gas emissions were explored, both resulting in an increase in the inter-annual fluctuations of the water level. In the scenario with higher emissions, projections also showed a long-term negative trend in water-level. To explore the possible response of biota to such water-level changes, species-area relationships of flora and aerial censuses of macro-fauna were analysed during an extraordinary dry period. Plant species richness at the basin scale was found to be highly resistant to hydrological changes, as the large dimension of the wetland acts to buffer against the water-level variations. However, local diversity decreased significantly with low water levels, leading to the loss of ecosystem resilience to additional stressors. The analysis of macro-fauna populations suggested that wetland provides refuge, in low water periods, for the animals with high dispersal ability (aquatic and migratory birds). On the contrary, the abundance of animals with low dispersal ability (mainly herbivorous species) was negatively impacted in low water periods, probably because they are required to search for alternative resources beyond the wetland borders. This period of resource scarcity was also related to increased mortality of large mammals (e.g. marsh deer) around water bodies with high anthropogenic enrichment and cyanobacteria dominance. The synergy between recurrent climatic fluctuations and additional stressors (i.e. biological invasions, eutrophication) presents an important challenge to the conservation of neotropical wetlands in the coming decades.

Bark beetle-induced tree mortality alters stand energy budgets due to water budget changes

NASA Astrophysics Data System (ADS)

Reed, David E.; Ewers, Brent E.; Pendall, Elise; Frank, John; Kelly, Robert

2018-01-01

Insect outbreaks are major disturbances that affect a land area similar to that of forest fires across North America. The recent mountain pine bark beetle ( D endroctonus ponderosae) outbreak and its associated blue stain fungi ( Grosmannia clavigera) are impacting water partitioning processes of forests in the Rocky Mountain region as the spatially heterogeneous disturbance spreads across the landscape. Water cycling may dramatically change due to increasing spatial heterogeneity from uneven mortality. Water and energy storage within trees and soils may also decrease, due to hydraulic failure and mortality caused by blue stain fungi followed by shifts in the water budget. This forest disturbance was unique in comparison to fire or timber harvesting because water fluxes were altered before significant structural change occurred to the canopy. We investigated the impacts of bark beetles on lodgepole pine ( Pinus contorta) stand and ecosystem level hydrologic processes and the resulting vertical and horizontal spatial variability in energy storage. Bark beetle-impacted stands had on average 57 % higher soil moisture, 1.5 °C higher soil temperature, and 0.8 °C higher tree bole temperature over four growing seasons compared to unimpacted stands. Seasonal latent heat flux was highly correlated with soil moisture. Thus, high mortality levels led to an increase in ecosystem level Bowen ratio as sensible heat fluxes increased yearly and latent heat fluxes varied with soil moisture levels. Decline in canopy biomass (leaf, stem, and branch) was not seen, but ground-to-atmosphere longwave radiation flux increased, as the ground surface was a larger component of the longwave radiation. Variability in soil, latent, and sensible heat flux and radiation measurements increased during the disturbance. Accounting for stand level variability in water and energy fluxes will provide a method to quantify potential drivers of ecosystem processes and services as well as lead to greater confidence in measurements for all dynamic disturbances.

Groundwater-level change and evaluation of simulated water levels for irrigated areas in Lahontan Valley, Churchill County, west-central Nevada, 1992 to 2012

USGS Publications Warehouse

Smith, David W.; Buto, Susan G.; Welborn, Toby L.

2016-09-14

The acquisition and transfer of water rights to wetland areas of Lahontan Valley, Nevada, has caused concern over the potential effects on shallow aquifer water levels. In 1992, water levels in Lahontan Valley were measured to construct a water-table map of the shallow aquifer prior to the effects of water-right transfers mandated by the Fallon Paiute-Shoshone Tribal Settlement Act of 1990 (Public Law 101-618, 104 Stat. 3289). From 1992 to 2012, approximately 11,810 water-righted acres, or 34,356 acre-feet of water, were acquired and transferred to wetland areas of Lahontan Valley. This report documents changes in water levels measured during the period of water-right transfers and presents an evaluation of five groundwater-flow model scenarios that simulated water-level changes in Lahontan Valley in response to water-right transfers and a reduction in irrigation season length by 50 percent.Water levels measured in 98 wells from 2012 to 2013 were used to construct a water-table map. Water levels in 73 of the 98 wells were compared with water levels measured in 1992 and used to construct a water-level change map. Water-level changes in the 73 wells ranged from -16.2 to 4.1 feet over the 20-year period. Rises in water levels in Lahontan Valley may correspond to annual changes in available irrigation water, increased canal flows after the exceptionally dry and shortened irrigation season of 1992, and the increased conveyance of water rights transferred to Stillwater National Wildlife Refuge. Water-level declines generally occurred near the boundary of irrigated areas and may be associated with groundwater pumping, water-right transfers, and inactive surface-water storage reservoirs. The largest water-level declines were in the area near Carson Lake.Groundwater-level response to water-right transfers was evaluated by comparing simulated and observed water-level changes for periods representing water-right transfers and a shortened irrigation season in areas near Fallon and Stillwater, Nevada. In the Stillwater modeled area, water rights associated with nearly 50 percent of the irrigated land were transferred from 1992 to 1998, represented by the model scenario reduction in groundwater recharge by 50 percent. The scenario resulted in a simulated average decline of 0.6 foot; average observed water-level change for the modeled area was estimated to be 0.0 foot, or no change. In the Fallon modeled area, transfers of water rights associated with 180 acres of land occurred from 1994 to 2008. The transfer is most similar to the scenario for removal of 320 acres of irrigated land. The model scenario resulted in simulated water-level declines of 0.1; water levels measured from 1994 to 2012 indicate no significant trends in water levels, or approximately zero change in water levels, for the Fallon modeled area.The model scenarios included the simulation of a irrigation season shortened by 50 percent, which was determined to have occurred in the 1992 irrigation season in both modeled areas. The shortening of the irrigation season in the Fallon modeled area resulted in simulated water-level declines of 1.1 feet; observed declines were estimated to be 1.3 feet. The Stillwater model simulations resulted in a simulated decline of 1.4 feet, and observed water levels declined an estimated 2.3 feet for the area. The estimated difference between simulated and observed water levels are 0.2 and 0.9 foot for the Fallon and Stillwater modeled areas, respectively. Observed water-level changes were generally within one standard deviation of changes from model simulations, based on the selected periods of comparison. Simulated and observed water-level changes agree well, generally within 1 foot; however, the model scenarios were only approximately similar to the observed conditions, and periods of comparison were generally shorter for the observed periods and included additional cumulative effects of water-right transfers. Climate variability was not considered in the model scenarios.

Salt and nitric oxide synthase inhibition-induced hypertension: kidney dysfunction and brain anti-oxidant capacity.

PubMed

Oktar, Süleyman; Ilhan, Selçuk; Meydan, Sedat; Aydin, Mehmet; Yönden, Zafer; Gökçe, Ahmet

2010-01-01

The specific aim of this study was to examine the effects of salt-loading on kidney function and brain antioxidant capacity. Wistar rats were divided into four groups: Control rats were given normal drinking water and no drug treatment for 2 weeks. LNNA group: rats were given normal drinking water and the nitric oxide (NO) inhibitor NG-nitro-L-arginine (L-NNA), 3 mg/kg/day. LNNA + Salt group: rats were given drinking water containing salt 2% and 3 mg/kg L-NNA. Salt group: rats were given drinking water containing salt 2% and no drug treatment. Basal blood pressure and the levels of serum BUN, creatinine, uric acid, cortisol, electrolyte, serum antioxidant capacity, and oxidative stress were measured. NO, superoxide dismutase (SOD), and catalase (CAT) levels were measured in the hypothalamus, brainstem, and cerebellum. Salt overload increased the blood pressure of the LNNA + Salt group. Salt-loading enhanced BUN, creatinine, sodium retention. High salt produced an increase in uric acid levels and a decrease in cortisol levels in serum. Additionally, the oxidative stress index in serum increased in the LNNA + Salt group. Salt-loading enhanced brain NO levels, but not SOD and CAT activity. L-NNA increased brain SOD activity, but not CAT and NO levels. In conclusion, salt-loading causes hypertension, kidney dysfunction, and enhances oxidative stress in salt-sensitive rats.

Cloud/climate sensitivity experiments

NASA Technical Reports Server (NTRS)

Roads, J. O.; Vallis, G. K.; Remer, L.

1982-01-01

A study of the relationships between large-scale cloud fields and large scale circulation patterns is presented. The basic tool is a multi-level numerical model comprising conservation equations for temperature, water vapor and cloud water and appropriate parameterizations for evaporation, condensation, precipitation and radiative feedbacks. Incorporating an equation for cloud water in a large-scale model is somewhat novel and allows the formation and advection of clouds to be treated explicitly. The model is run on a two-dimensional, vertical-horizontal grid with constant winds. It is shown that cloud cover increases with decreased eddy vertical velocity, decreased horizontal advection, decreased atmospheric temperature, increased surface temperature, and decreased precipitation efficiency. The cloud field is found to be well correlated with the relative humidity field except at the highest levels. When radiative feedbacks are incorporated and the temperature increased by increasing CO2 content, cloud amounts decrease at upper-levels or equivalently cloud top height falls. This reduces the temperature response, especially at upper levels, compared with an experiment in which cloud cover is fixed.

Hydrogeology of, and ground-water flow in, a valley-fill and carbonate-rock aquifer system near Long Valley in the New Jersey Highlands

USGS Publications Warehouse

Nicholson, R.S.; McAuley, S.D.; Barringer, J.L.; Gordon, A.D.

1996-01-01

The hydrogeology of and ground-water flow in a valley-fill and carbonate-rock aquifer system were evaluated by using numerical-modeling techniques and geochemical interpretations to address concerns about the adequacy of the aquifer system to meet increasing demand for water. The study was conducted during 1987-90 by the U.S. Geological Survey, in cooperation with the New Jersey Department of Environmental Protection and Energy. The effects of recent and anticipated ground-water withdrawals on water levels, stream base flows, and water budgets were estimated. Simulation results indicate that recent withdrawals of 4.7 million gallons per day have resulted in water-level declines of up to 35 feet. Under conditions of increases in withdrawals of 121 percent, water levels would decline up to an additional 28 feet. The magnitude of predicted average base-flow depletion, when compared with historic low flows, indicates that projected increases in withdrawals may substantially deplete seasonal low flow of Drakes Brook and South Branch Raritan River. Results of a water-budget analysis indicate that the sources of water to additional supply wells would include leakage from the overlying valley-fill aquifer and induced leakage of surface water into the aquifer system. Results of water-quality analyses indicate that human activities are affecting the quality of the ground water. With the exception of an elevated iron concentration in water from one well, concentrations of inorganic constituents in water from 75 wells did not exceed New Jersey primary or secondary drinking-water regulations. Volatile organic compounds were detected in water from several wells; in two samples, concentrations of specific compounds exceeded drinking-water regulations.

Increase in forest water-use efficiency as atmospheric carbon dioxide concentrations rise.

PubMed

Keenan, Trevor F; Hollinger, David Y; Bohrer, Gil; Dragoni, Danilo; Munger, J William; Schmid, Hans Peter; Richardson, Andrew D

2013-07-18

Terrestrial plants remove CO2 from the atmosphere through photosynthesis, a process that is accompanied by the loss of water vapour from leaves. The ratio of water loss to carbon gain, or water-use efficiency, is a key characteristic of ecosystem function that is central to the global cycles of water, energy and carbon. Here we analyse direct, long-term measurements of whole-ecosystem carbon and water exchange. We find a substantial increase in water-use efficiency in temperate and boreal forests of the Northern Hemisphere over the past two decades. We systematically assess various competing hypotheses to explain this trend, and find that the observed increase is most consistent with a strong CO2 fertilization effect. The results suggest a partial closure of stomata-small pores on the leaf surface that regulate gas exchange-to maintain a near-constant concentration of CO2 inside the leaf even under continually increasing atmospheric CO2 levels. The observed increase in forest water-use efficiency is larger than that predicted by existing theory and 13 terrestrial biosphere models. The increase is associated with trends of increasing ecosystem-level photosynthesis and net carbon uptake, and decreasing evapotranspiration. Our findings suggest a shift in the carbon- and water-based economics of terrestrial vegetation, which may require a reassessment of the role of stomatal control in regulating interactions between forests and climate change, and a re-evaluation of coupled vegetation-climate models.

Drinking water contributes to high salt consumption in young adults in coastal Bangladesh.

PubMed

Talukder, Mohammad Radwanur Rahman; Rutherford, Shannon; Phung, Dung; Malek, Abdul; Khan, Sheela; Chu, Cordia

2016-04-01

Increasing salinity of freshwater from environmental and anthropogenic influences is threatening the health of 35 million inhabitants in coastal Bangladesh. Yet little is known about the characteristics of their exposure to salt (sodium), a major risk factor for hypertension and related chronic diseases. This research examined sodium consumption levels and associated factors in young adults. We assessed spot urine samples for 282 participants (19-25 years) during May-June 2014 in a rural sub-district in southwestern coastal Bangladesh and measured sodium levels of their potable water sources. The significant factors associated with high sodium consumption were determined from logistic regression analyses. Mean sodium content in tube-well water (885 mg/L) was significantly higher than pond water (738 mg/L) (P = 0.01). Fifty three percent of subjects were consuming sodium at levels above the WHO recommended level (≥2 g/day). The users of tube-well water were more likely to consume sodium above this recommended level than pond water users. Salinity problems are projected to increase with climate change, and with large populations potentially at risk, appropriate public health and behavior-change interventions are an urgent priority for this vulnerable coastal region along with targeted research to better understand sodium exposure pathways and health benefits of alternative water supplies.

[Relationships between urbanization and water resource utilization in Dongting Lake District of South-central China].

PubMed

Li, Jing-Zhi; Zhu, Xiang; Li, Jing-Bao; Xu, Mei

2013-06-01

By using analytic hierarchy process and entropy method, the evaluation index system and the response relationship model of comprehensive development level of urbanization and comprehensive development and utilization potential of water resources in Dongting Lake District were constructed, with the key affecting factors, their change characteristics, and response characteristics from 2001 to 2010 analyzed. During the study period, the Dongting Lake District was undergoing a rapid development of urbanization, and at a scale expansion stage. The economic and social development level was lagged behind the population and area increase, and the quality and efficiency of urbanization were still needed to be improved. With the advance of urbanization, the water consumption increased yearly, and the water resources utilization efficiency and management level improved steadily. However, the background condition of water resources and their development and utilization level were more affected by hydrological environment rather than urbanization. To a certain extent, the development of urbanization in 2001, 2002, 2005, 2006, 2007, 2009 was slowed down by the shortage of water resources. At present, Dongting Lake region was confronted with the dual task of improving the level and quality of urbanization, and hence, it would be necessary to reform the traditional epitaxial expansion of urbanization and to enhance the water resource support capability.

Ganga water pollution: A potential health threat to inhabitants of Ganga basin.

PubMed

Dwivedi, Sanjay; Mishra, Seema; Tripathi, Rudra Deo

2018-05-18

The water quality of Ganga, the largest river in Indian sub-continent and life line to hundreds of million people, has severely deteriorated. Studies have indicated the presence of high level of carcinogenic elements in Ganga water. We performed extensive review of sources and level of organic, inorganic pollution and microbial contamination in Ganga water to evaluate changes in the level of various pollutants in the recent decade in comparison to the past and potential health risk for the population through consumption of toxicant tainted fishes in Ganga basin. A systematic search through databases, specific websites and reports of pollution regulatory agencies was conducted. The state wise level of contamination was tabulated along the Ganga river. We have discussed the major sources of various pollutants with particular focus on metal/metalloid and pesticide residues. Bioaccumulation of toxicants in fishes of Ganga water and potential health hazards to humans through consumption of tainted fishes was evaluated. The level of pesticides in Ganga water registered a drastic reduction in the last decade (i.e. after the establishment of National Ganga River Basin Authority (NGRBA) in 2009), still the levels of some organochlorines are beyond the permissible limits for drinking water. Conversely the inorganic pollutants, particularly carcinogenic elements have increased several folds. Microbial contamination has also significantly increased. Hazard quotient and hazard index indicated significant health risk due to metal/metalloid exposure through consumption of tainted fishes from Ganga. Target cancer risk assessment showed high carcinogenic risk from As, Cr, Ni and Pb as well as residues of DDT and HCHs. Current data analysis showed that Ganga water quality is deteriorating day by day and at several places even in upper stretch of Ganga the water is not suitable for domestic uses. Although there is positive impact of ban on persistent pesticides with decreasing trend of pesticide residues in Ganga water, the increasing trend of trace and toxic elements is alarming and the prolong exposure to polluted Ganga water and/or consumption of Ganga water fishes may cause serious illness including cancer. Copyright © 2018 Elsevier Ltd. All rights reserved.

Assessment of groundwater availability in the Northern Atlantic Coastal Plain aquifer system From Long Island, New York, to North Carolina

USGS Publications Warehouse

Masterson, John P.; Pope, Jason P.; Fienen, Michael N.; Monti, Jr., Jack; Nardi, Mark R.; Finkelstein, Jason S.

2016-08-31

Executive SummaryThe U.S. Geological Survey began a multiyear regional assessment of groundwater availability in the Northern Atlantic Coastal Plain (NACP) aquifer system in 2010 as part of its ongoing regional assessments of groundwater availability of the principal aquifers of the Nation. The goals of this national assessment are to document effects of human activities on water levels and groundwater storage, explore climate variability effects on the regional water budget, and provide consistent and integrated information that is useful to those who use and manage the groundwater resource. As part of this nationwide assessment, the USGS evaluated available groundwater resources within the NACP aquifer system from Long Island, New York, to northeastern North Carolina.The northern Atlantic Coastal Plain physiographic province depends heavily on groundwater to meet agricultural, industrial, and municipal needs. The groundwater assessment of the NACP aquifer system included an evaluation of how water use has changed over time; this evaluation primarily used groundwater budgets and development of a numerical modeling tool to assess system responses to stresses from future human uses and climate trends.This assessment focused on multiple spatial and temporal scales to examine changes in groundwater pumping, storage, and water levels. The regional scale provides a broad view of the sources and demands on the system with time. The sub-regional scale provides an evaluation of the differing response of the aquifer system across geographic areas allowing for closer examination of the interaction between different aquifers and confining units and the changes in these interactions under pumping and recharge conditions in 2013 and hydrologic stresses as much as 45 years in the future. By focusing on multiple scales, water-resource managers may utilize this study to understand system response to changes as they affect the system as a whole.The NACP aquifer system extends from Long Island to northeastern North Carolina, and includes aquifers primarily within New York, New Jersey, Delaware, Maryland, Virginia, and North Carolina. The seaward-dipping sedimentary wedge that underlies the northern Atlantic Coastal Plain physiographic province forms a complex groundwater system. Although the NACP aquifer system is recognized by the U.S. Geological Survey as one of the smallest of the 66 principal aquifer systems in the Nation, it ranks 13th overall in terms of total groundwater withdrawals and is 7th in population served. Despite abundant precipitation [about 45 inches per year (in/yr)], the supply of fresh surface water in this region is limited because many of the surface waters in this area are brackish estuaries, contributing to why many communities in the northern Atlantic Coastal Plain physiographic province rely heavily on groundwater to meet their water needs.Increases in population and changes in land use during the past 100 years have resulted in diverse increased demands for freshwater throughout the northern Atlantic Coastal Plain physiographic province with groundwater serving as a vital source of drinking water for the nearly 20 million people who live in the region. Total groundwater withdrawal in 2013 was estimated to be about 1,300 million gallons per day (Mgal/d) and accounts for about 40 percent of the drinking water supply with the densely populated areas tending to have the highest rates of withdrawals and, therefore, being most susceptible to effects from these withdrawals over time.Water levels in many of the confined aquifers are decreasing by as much as 2 feet per year (ft/yr) in response to extensive development and subsequent increased withdrawals throughout the region. Total water-level decreases (drawdowns) are more than 100 feet (ft) in some aquifers from their predevelopment (before 1900) levels. These drawdowns extend across state lines and under the Chesapeake and Delaware Bays, creating the potential for interstate aquifer management issues. Regional water-resources managers in the northern Atlantic Coastal Plain physiographic province face challenges beyond competing local domestic, industrial, agricultural, and environmental demands for water. Large changes in regional water use have made the State-level management of aquifer resources more difficult because of hydrologic effects that extend beyond State boundaries.The northern Atlantic Coastal Plain physiographic province is underlain by a wedge of unconsolidated to partially consolidated sediments that are typically thousands of feet thick along the coastline with a maximum thickness of about 10,000 ft near the edge of the continental shelf. The NACP aquifer system consists of nine confined aquifers and nine confining units capped by an unconfined surficial aquifer that is bounded laterally from the west by the contact between Coastal Plain sediments and the upland Piedmont bedrock. This aquifer system extends to the east to the limit of the Continental Shelf, however, the boundary between fresh and saline groundwater is considered to be much closer to the shoreline and varies vertically by aquifer.Precipitation over the region for average conditions from 2005 to 2009 is about 61,800 Mgal/d, but about 70 percent of it is lost to evapotranspiration resulting in an inflow of about 19,600 Mgal/d entering the groundwater system as aquifer recharge. Most of this recharge enters the aquifer system and flows through the shallow unconfined aquifer and either discharges to streams or directly to coastal waters without reaching the deep, confined aquifer system. In addition to recharge from precipitation, other sources of water include the return of wastewater from domestic septic systems of about 240 Mgal/d, about 60 Mgal/d of water released from storage in the confined system, and about 30 Mgal/d of lateral inflow at the boundary between freshwater and saltwater in response to pumping for conditions in 2013.The outflow needed to balance the inflows was subdivided between streamflow, discharge to tidal portions of streams, and coastal discharge. The hydrologic budget developed for current [2013] conditions determined that 93 percent of the total outflow was to surface waters with about 70 percent divided evenly between streamflow and shallow coastal discharge and 23 percent as discharge to tidal waters. The remaining 7 percent of the total outflow components include withdrawals from both the surficial and confined aquifers of the groundwater system.The groundwater availability assessment of the NACP aquifer system highlights the importance of analyses at both the regional and local scales to understand how changes in land use, water use, and climate have affected groundwater resources and how these resources may change in the future. The investigation included assessments of the regional changes in water levels and budgets across State lines, the importance of considering storage change in the confining units, the response of the aquifer system to a continuation of current [2013] hydrologic stresses into the future, and the potential effects of climate change and sea-level rise on the aquifer system.The Potomac aquifer group includes two of the most widely used aquifers in the NACP aquifer system, the Potomac-Patapsco and Potomac-Patuxent regional aquifers, providing about 24 percent of the total groundwater used in the region. Withdrawals from large pumping centers in this deep, confined aquifer group have resulted in substantial decreases in water-levels across state lines, particularly between southern Virginia and northeastern North Carolina as well as between southern New Jersey and northern Delaware where water levels in the Potomac-Patapsco aquifer have decreased by as much as 200 ft and 50 ft, respectively from predevelopment to current [2013] conditions. This response in water levels also is reflected in changes in water budgets where, for example, about 20 percent of the total response to pumping in Virginia is met by inducing flow from adjacent States. Understanding and quantifying these hydrologic effects that extend beyond State boundaries is critical for the State- and regional-level management of aquifer resources.The cumulative storage loss from the intervening confining units throughout the entire NACP aquifer system was about 35 percent of the total storage loss from predevelopment to current [2013] conditions. In geographic areas such as Delmarva Peninsula, Maryland, and New Jersey, the water released from storage in the confining units makes up the majority of the total storage release from the groundwater system and is becoming proportionally more important over time as the surficial aquifer approaches equilibrium with respect to pumping and recharge stresses as of 2013.Storage loss from the confining units is of particular concern because, unlike in the sands that comprise the confined aquifers, water removed from the clayey confining unit sediments cannot be replenished as these units gradually compress. This non-recoverable storage loss, if great enough, can result in land subsidence where these units are thick and the release from storage is relatively large and contributes to increased concerns for sea-level rise in areas such as the lower portion of the Chesapeake Bay.Groundwater usage increased dramatically in the NACP aquifer system during post-World War II era from the mid-1940s to early the 1980s, with withdrawals increasing from about 400 Mgal/d to more than 1,300 Mgal/d. Although groundwater withdrawals have been relatively constant since the early 1980s, about half of the total groundwater withdrawn from the NACP aquifer system since 1900 was withdrawn in the past 30 years. An analysis of the response of the groundwater system to a continuation of the current [2013] pumping for an additional 30 years into the future shows that the flow system continues to adjust in terms of changes in water budget components, water levels, and the boundary between freshwater and saltwater as it approaches equilibrium. The largest change in water budget components is the reduction in the amount of water released from storage.Across the entire NACP aquifer system, the reduction of storage release from 7 to 4 percent of the total water budget change is accounted for by reductions in groundwater discharge to streams and coastal waters. Locally, a similar response is calculated for each of the geographic areas except for Virginia where the amount of water released from storage accounts for about 25 percent of the total change in water budget. This finding suggests that the groundwater flow system in Virginia is not approaching equilibrium under the current [2013] stresses and, therefore, water levels will continue to decrease even if the pumping remains constant.An analysis of the change in water levels in the Potomac-Patapsco aquifer as pumping is continued 30 years into the future reveals that the largest decreases in water levels throughout the NACP aquifer system will occur in the southern Virginia and northeastern North Carolina parts of the study area. It is these areas that also see the greatest potential for increased lateral movement of saline groundwater in the deep, confined portion of the groundwater flow system in response to a continuation of the current [2013] pumping rates.The potential effects of long-term climate change and variability on the hydrologic system and availability of water resources in the NACP aquifer system continue to be of serious societal concern. These concerns include the effects of changes in aquifer recharge and in sea-level rise on the groundwater flow system. An assessment of the potential effects of a prolonged drought during current [2013] pumping conditions indicated that the reductions in recharge associated with droughts, including additional irrigation withdrawals required to meet increased crop water demand, have the greatest effects on water levels and streamflows in the surficial aquifer, and changes in water levels in the confined aquifers primarily resulted from the increased withdrawals associated with increased irrigation pumping; this response was most apparent in the Delmarva Peninsula. These results suggest that water levels may not be susceptible to the effects of droughts in the confined aquifers of the NACP aquifer system not used for irrigation, unlike in the unconfined surficial aquifer.A second analysis also was conducted to assess the effects of sea-level rise on the groundwater system throughout the northern Atlantic Coastal Plain physiographic province because recent analyses of the relative rates of sea-level rise along the Atlantic coast indicate that the Mid-Atlantic region represents a hot spot with anomalously higher rates of sea-level rise than observed elsewhere in the United States. Groundwater levels rose from 0 to 3 ft in response to a 3-ft simulated change in sea-level position, with the largest response occurring along the shoreline and away from non-tidal streams. About 37 percent (or 10,000 square miles) of the area of the northern Atlantic Coastal Plain physiographic province may experience about a 0.5-ft or more increase in water levels with the 3-ft increase in sea-level position, whereas about 18 percent (almost 5,000 square miles) of land of the northern Atlantic Coastal Plain physiographic province may experience a 2-ft or more increase in water levels with the 3-ft increase in sea-level position.These increases in the water table are of particular concern in low-lying areas where the unsaturated (vadose) zone is already thin, thus creating concerns for groundwater inundation of subsurface infrastructure, such as basements, septic systems, and subway systems. This increase in the water table also will likely alter the distribution of groundwater discharge to surface-water bodies thus increasing groundwater flow to streams that would have otherwise discharged directly to coastal waters. Throughout the NACP aquifer system, this redistribution of groundwater discharge results in an additional 2 percent of base flow in streams. Although the increases in groundwater discharge to streams (and corresponding decreases in discharge to coastal waters) calculated for the entire NACP aquifer system and its geographic areas represent only a small increase compared with current [2013] conditions, this redistribution of groundwater discharge from the coast to streams locally can alter the delivery of freshwater input to coastal receiving waters and have ecohydrological implications on the sensitive ecosystems which rely on a balance of groundwater discharge and surface-water flow.

Prediction and assessment of the disturbances of the coal mining in Kailuan to karst groundwater system

NASA Astrophysics Data System (ADS)

Sun, Wenjie; Wu, Qiang; Liu, Honglei; Jiao, Jian

Coal resources and water resources play an essential and strategic role in the development of China's social and economic development, being the priority for China's medium and long technological development. As the mining of the coal extraction is increasingly deep, the mine water inrush of high-pressure confined karst water becomes much more a problem. This paper carried out research on the hundred-year old Kailuan coal mine's karst groundwater system. With the help of advanced Visual Modflow software and numerical simulation method, the paper assessed the flow field of karst water area under large-scale exploitation. It also predicted the evolution ofgroundwaterflow field under different mining schemes of Kailuan Corp. The result shows that two cones of depression are formed in the karst flow field of Zhaogezhuang mining area and Tangshan mining area, and the water levels in two cone centers are -270 m and -31 m respectively, and the groundwater generally flows from the northeast to the southwest. Given some potential closed mines in the future, the mine discharge will decrease and the water level of Ordovician limestone will increase slightly. Conversely, given increase of coal yield, the mine drainage will increase, falling depression cone of Ordovician limestone flow field will enlarge. And in Tangshan's urban district, central water level of the depression cone will move slightly towards north due to pumping of a few mines in the north.

Evaluation of ground-water recharge along the Gila River as a result of the flood of October 1983, in and near the Gila River Indian Reservation, Maricopa and Pinal counties, Arizona

USGS Publications Warehouse

Konieczki, A.D.; Anderson, S.R.

1990-01-01

Flow in the Gila River from the flood of October 1983 infiltrated the stream channel and recharged the groundwater system along the Gila River floodplain from Ashurst-Hayden Dam to the confluence with the Salt River. Changes in groundwater levels from January 1983 to March 1984 confirmed the occurrence of recharge to the groundwater system. The average water level change for 74 wells was +24.2 ft. The water-level rise was greatest in the reach from river mile 15 to river mile 22, where the average water level change for 10 wells was +59.4 ft. The average water level increase for 28 miles from river mile 40 to river mile 71 was +14.2 ft. Estimates of recharge from January 1983 to March 1984 ranged from 440,000 to 640, 000 acre-ft. A water budget method and a water level change method were used to estimate the recharge to the aquifer. At least 46% to 66% of the recharge was the result of streamflow infiltration from the Gila River during October 1983 to February 1984. The increase in aquifer storage was one to two times greater than the quantity of groundwater pumped from the Gila River Indian Reservation during the 10 years preceding the flood. (USGS)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aschengrau, A.; Zierler, S.; Cohen, A.

To investigate the relationship between community drinking water quality and spontaneous abortion, we compared trace element levels in the drinking water of 286 women having a spontaneous abortion through 27 wk gestation with that of 1,391 women having live births. Trace element levels were gathered from analyses of public tap water supplies from the communities where the women resided during pregnancy. After adjustment for potential confounders, an increase in the frequency of spontaneous abortion was associated with detectable levels of mercury; high levels of arsenic, potassium, and silica; moderately hard water, and surface water. In contrast, a decrease in themore » frequency of spontaneous abortion was associated with high levels of alkalinity and sulfate, and any detectable level of nitrate. These results require further corroboration because there is a paucity of data investigating this issue.« less

Ground-water, surface-water, and water-chemistry data, Black Mesa area, Northeastern Arizona: 1999

USGS Publications Warehouse

Thomas, Blakemore E.; Truini, Margot

2000-01-01

The N aquifer is the major source of water in the 5,400-square-mile area of Black Mesa in northeastern Arizona. Availability of water is an important issue in this area because of continued industrial and municipal use, a growing population, and a precipitation of only about 6 to 12 inches per year. The monitoring program in Black Mesa has been operating since 1971 and is designed to determine the long-term effects of ground-water withdrawals from the N aquifer for industrial and municipal uses. The monitoring program includes measurements of (1) ground-water pumping, (2) ground-water levels, (3) spring discharge, (4) surface-water discharge, and (5) ground-water chemistry. In 1999, total ground-water withdrawals were 7,110 acre-feet, industrial use was 4,210 acre-feet, and municipal use was 2,900 acre-feet. From 1998 to 1999, total withdrawals increased by 0.7 percent, industrial use increased by 4 percent, and municipal use decreased by 4 percent. From 1998 to 1999, water levels declined in 11 of 15 wells in the unconfined part of the aquifer, and the median decline was 0.7 foot. Water levels declined in 14 of 16 wells in the confined part of the aquifer, and the median decline was 1.2 feet. From the prestress period (prior to 1965) to 1999, the median water-level decline in 31 wells was 10.6 feet. Median water-level changes were 0.0 foot for 15 wells in the unconfined part of the aquifer and a decline of 45.5 feet in 16 wells in the confined part. From 1998 to 1999, discharges were measured annually at four springs. Discharges declined 30 percent and 3 percent at 2 springs, did not change at 1 spring, and increased by 11 percent at 1 spring. For the past 10 years, discharges from the four springs have fluctuated; however, an increasing or decreasing trend was not observed. Continuous records of surface-water discharge have been collected from July 1976 to 1999 at Moenkopi Wash, July 1996 to 1999 at Laguna Creek, June 1993 to 1999 at Dinnebito Wash, and April 1994 to 1999 at Polacca Wash. Median flows for November, December, January, and February of each water year are used as an index of ground-water discharge to those streams. Increasing or decreasing trends are not apparent in these median winter flows for the periods of record. In 1999, water samples were collected from 12 wells and 4 springs and analyzed for selected chemical constituents. Dissolved-solids concentrations ranged from 91 to 630 milligrams per liter. Water samples from 10 of the wells and the 4 springs had less than 350 milligrams per liter of dissolved solids. Water-chemistry data are available for nine wells and four springs from about the mid-1980s. For that time period, the data from those sites have remained fairly stable. From 1987 to 1999, concentrations of dissolved solids, chloride, and sulfate may have increased slightly in samples from Moenkopi School Spring.

Physical and virtual water transfers for regional water stress alleviation in China

PubMed Central

Zhao, Xu; Liu, Junguo; Liu, Qingying; Tillotson, Martin R.; Guan, Dabo; Hubacek, Klaus

2015-01-01

Water can be redistributed through, in physical terms, water transfer projects and virtually, embodied water for the production of traded products. Here, we explore whether such water redistributions can help mitigate water stress in China. This study, for the first time to our knowledge, both compiles a full inventory for physical water transfers at a provincial level and maps virtual water flows between Chinese provinces in 2007 and 2030. Our results show that, at the national level, physical water flows because of the major water transfer projects amounted to 4.5% of national water supply, whereas virtual water flows accounted for 35% (varies between 11% and 65% at the provincial level) in 2007. Furthermore, our analysis shows that both physical and virtual water flows do not play a major role in mitigating water stress in the water-receiving regions but exacerbate water stress for the water-exporting regions of China. Future water stress in the main water-exporting provinces is likely to increase further based on our analysis of the historical trajectory of the major governing socioeconomic and technical factors and the full implementation of policy initiatives relating to water use and economic development. Improving water use efficiency is key to mitigating water stress, but the efficiency gains will be largely offset by the water demand increase caused by continued economic development. We conclude that much greater attention needs to be paid to water demand management rather than the current focus on supply-oriented management. PMID:25583516

Physical and virtual water transfers for regional water stress alleviation in China.

PubMed

Zhao, Xu; Liu, Junguo; Liu, Qingying; Tillotson, Martin R; Guan, Dabo; Hubacek, Klaus

2015-01-27

Water can be redistributed through, in physical terms, water transfer projects and virtually, embodied water for the production of traded products. Here, we explore whether such water redistributions can help mitigate water stress in China. This study, for the first time to our knowledge, both compiles a full inventory for physical water transfers at a provincial level and maps virtual water flows between Chinese provinces in 2007 and 2030. Our results show that, at the national level, physical water flows because of the major water transfer projects amounted to 4.5% of national water supply, whereas virtual water flows accounted for 35% (varies between 11% and 65% at the provincial level) in 2007. Furthermore, our analysis shows that both physical and virtual water flows do not play a major role in mitigating water stress in the water-receiving regions but exacerbate water stress for the water-exporting regions of China. Future water stress in the main water-exporting provinces is likely to increase further based on our analysis of the historical trajectory of the major governing socioeconomic and technical factors and the full implementation of policy initiatives relating to water use and economic development. Improving water use efficiency is key to mitigating water stress, but the efficiency gains will be largely offset by the water demand increase caused by continued economic development. We conclude that much greater attention needs to be paid to water demand management rather than the current focus on supply-oriented management.

Climate Sensitivity Runs and Regional Hydrologic Modeling for Predicting the Response of the Greater Florida Everglades Ecosystem to Climate Change

NASA Astrophysics Data System (ADS)

Obeysekera, Jayantha; Barnes, Jenifer; Nungesser, Martha

2015-04-01

It is important to understand the vulnerability of the water management system in south Florida and to determine the resilience and robustness of greater Everglades restoration plans under future climate change. The current climate models, at both global and regional scales, are not ready to deliver specific climatic datasets for water resources investigations involving future plans and therefore a scenario based approach was adopted for this first study in restoration planning. We focused on the general implications of potential changes in future temperature and associated changes in evapotranspiration, precipitation, and sea levels at the regional boundary. From these, we developed a set of six climate and sea level scenarios, used them to simulate the hydrologic response of the greater Everglades region including agricultural, urban, and natural areas, and compared the results to those from a base run of current conditions. The scenarios included a 1.5 °C increase in temperature, ±10 % change in precipitation, and a 0.46 m (1.5 feet) increase in sea level for the 50-year planning horizon. The results suggested that, depending on the rainfall and temperature scenario, there would be significant changes in water budgets, ecosystem performance, and in water supply demands met. The increased sea level scenarios also show that the ground water levels would increase significantly with associated implications for flood protection in the urbanized areas of southeastern Florida.

Ground-water resources of Greeley and Wichita counties, Western Kansas

USGS Publications Warehouse

Slagle, Steven E.; Weakly, Edward C.

1975-01-01

Unconsolidated deposits of sand, silt, clay, and gravel compose the principal aquifer in Greeley and Wichita Counties. The deposits are as much as 300 feet (91 m) 2/ thick, of which as much as 145 feet (44 m) is saturated.In 1972, there were about 1,040 large-capacity wells--yielding 100 gallons per minute (6.3 1/s) or more--in the counties, mostly for irrigation supplies. The wells yield as much as 2,000 gallons per minute (130 1/s). Withdrawals of ground water average about 220,000 acre-feet (270 hm3) annually.Water levels have declined in parts of the area where large-capacity wells are concentrated, resulting in as much as 60-percent reduction in saturated thickness. Water-level declines during 1948-72 ranged from less than 10 to about 55 feet (3-17 m). The largest decline, about 55 feet (17 m), has occurred near Leoti, in central Wichita County. As of January 1972, about 5 million acre-feet (6,000 hm) of ground water were in storage in Greeley and Wichita Counties; however, only about 70 percent of this amount is considered to be available for pumping.The water from the unconsolidated aquifer is a mixed chemical type in which calcium, sodium, and bicarbonate are the principal constituents. Generally, the water is suitable for all common domestic, stock, and irrigation uses.Price increases for grain in 1973 and absence of acreage controls probably will encourage additional development of ground water for irrigation. Increased withdrawals will, however, accelerate the rate of water-level decline and reduction in ground-water storage. Increased water-level declines will be accompanied in most of the area by noticeable decreases in well yields. Any additional increase in the rate of withdrawal in areas where saturated thickness has declined about 40 percent or more may significantly shorten the economic life of the aquifer. Additional development in these areas should be considered with regard to increasing pumping costs and decreasing well yields. Development of the ground-water resource could be managed in several ways. The formation of Kansas Ground-Water Management District Number 1 provides a means by which local water users can decide on various management alternatives that would affect the future of their irrigation supply.

Simulated interaction between freshwater and saltwater and effects of ground-water pumping and sea-level change, lower Cape Cod aquifer system, Massachusetts

USGS Publications Warehouse

Masterson, John P.

2004-01-01

The U.S. Geological Survey, in cooperation with the National Park Service, Massachusetts Executive Office of Environmental Affairs, Cape Cod Commission, and the Towns of Eastham, Provincetown, Truro, and Wellfleet, began an investigation in 2000 to improve the understanding of the hydrogeology of the four freshwater lenses of the Lower Cape Cod aquifer system and to assess the effects of changing ground-water pumping, recharge conditions, and sea level on ground-water flow in Lower Cape Cod, Massachusetts. A numerical flow model was developed with the computer code SEAWAT to assist in the analysis of freshwater and saltwater flow. Model simulations were used to determine water budgets, flow directions, and the position and movement of the freshwater/saltwater interface. Model-calculated water budgets indicate that approximately 68 million gallons per day of freshwater recharge the Lower Cape Cod aquifer system with about 68 percent of this water moving through the aquifer and discharging directly to the coast, 31 percent flowing through the aquifer, discharging to streams, and then reaching the coast as surface-water discharge, and the remaining 1 percent discharging to public-supply wells. The distribution of streamflow varies greatly among flow lenses and streams; in addition, the subsurface geology greatly affects the position and movement of the underlying freshwater/saltwater interface. The depth to the freshwater/saltwater interface varies throughout the study area and is directly proportional to the height of the water table above sea level. Simulated increases in sea level appear to increase water levels and streamflows throughout the Lower Cape Cod aquifer system, and yet decrease the depth to the freshwater/saltwater interface. The resulting change in water levels and in the depth to the freshwater/saltwater interface from sea-level rise varies throughout the aquifer system and is controlled largely by non-tidal freshwater streams. Pumping from large-capacity municipal-supply wells increases the potential for effects on surface-water bodies, which are affected by pumping and wastewater-disposal locations and rates. Pumping wells that are upgradient of surface-water bodies potentially capture water that would otherwise discharge to these surface-water bodies, thereby reducing streamflow and pond levels. Kettle-hole ponds, such as Duck Pond in Wellfleet, that are near the top of a freshwater flow lens, appear to be more susceptible to changing pumping and recharge conditions than kettle-hole ponds closer to the coast or near discharge boundaries, such as the Herring River.

Recalibration of a ground-water flow model of the Mississippi River Valley alluvial aquifer of northeastern Arkansas, 1918-1998, with simulations of water levels caused by projected ground-water withdrawals through 2049

USGS Publications Warehouse

Reed, Thomas B.

2003-01-01

A digital model of the Mississippi River Valley alluvial aquifer in eastern Arkansas was used to simulate ground-water flow for the period from 1918 to 2049. The model results were used to evaluate effects on water levels caused by demand for ground water from the alluvial aquifer, which has increased steadily for the last 40 years. The model results showed that water currently (1998) is being withdrawn from the aquifer at rates greater than what can be sustained for the long term. The saturated thickness of the alluvial aquifer has been reduced in some areas resulting in dry wells, degraded water quality, decreased water availability, increased pumping costs, and lower well yields. The model simulated the aquifer from a line just north of the Arkansas-Missouri border to south of the Arkansas River and on the east from the Mississippi River westward to the less permeable geologic units of Paleozoic age. The model consists of 2 layers, a grid of 184 rows by 156 columns, and comprises 14,118 active cells each measuring 1 mile on a side. It simulates time periods from 1918 to 1998 along with further time periods to 2049 testing different pumping scenarios. Model flux boundary conditions were specified for rivers, general head boundaries along parts of the western side of the model and parts of Crowleys Ridge, and a specified head boundary across the aquifer further north in Missouri. Model calibration was conducted for observed water levels for the years 1972, 1982, 1992, and 1998. The average absolute residual was 4.69 feet and the root-mean square error was 6.04 feet for the hydraulic head observations for 1998. Hydraulic-conductivity values obtained during the calibration process were 230 feet per day for the upper layer and ranged from 230 to 730 feet per day for the lower layer with the maximum mean for the combined aquifer of 480 feet per day. Specific yield values were 0.30 throughout the model and specific storage values were 0.000001 inverse-feet throughout the model. Areally specified recharge rates ranged from 0 to about 30 inches and total recharge increased from 1972 to 1998 by a factor of about four. Water levels caused by projected ground-water withdrawals were simulated using the calibrated model. Simulations represented a period of 50 years into the future in three scenarios with either unchanged pumpage, pumpage increased by historic trends, or pumpage increased by historic trends except in two areas of the Grand Prairie. If pumping remains at 1997 rates, this produces extreme water-level declines (areas where model cells have gone dry or where the water level in the aquifer is equal to or less than the original saturated thickness, assuming confined conditions in the aquifer everywhere in the formation in predevelopment times) in the aquifer in two areas of the aquifer (one in the Grand Prairie area between the Arkansas and White Rivers and the other west of Crowleys Ridge along the Cache River) with about 400 square miles going dry. Increasing the pumping rates to that which would be projected using historic data led to increased extreme water-level declines in both areas with about 1,300 square miles going dry. Declines in both scenarios generally occurred most rapidly between 2009 and 2019. Reducing the pumping rates to 90 percent of that used for projected historic rates in areas between the Arkansas and White Rivers relating to two diversion projects of the U.S. Army Corps of Engineers and other agencies did little to decrease the extreme water-level declines. However, these pumpage reductions are small (amounting to about 16 percent of the reductions that could result from implementation of these diversion projects).

Analysis of the ecological water diversion project in Wenzhou City

NASA Astrophysics Data System (ADS)

Xu, Haibo; Fu, Lei; Lin, Tong

2018-02-01

As a developed city in China, Wenzhou City has been suffered from bad water quality for years. In order to improve the river network water quality, an ecological water diversion project was designed and executed by the regional government. In this study, an investigation and analysis of the regional ecological water diversion project is made for the purpose of examining the water quality improvements. A numerical model is also established, different water diversion flow rates and sewer interception levels are considered during the simulation. Simulation results reveal that higher flow rate and sewer interception level will greatly improve the river network water quality in Wenzhou City. The importance of the flow rate and interception level has been proved and future work will be focused on increasing the flow rate and upgrading the sewer interception level.

The Impact of Commercially Treated Oil and Gas Produced Water Discharges on Bromide Concentrations and Modeled Brominated Trihalomethane Disinfection Byproducts at two Downstream Municipal Drinking Water Plants in the Upper Allegheny River, Pennsylvania, USA

EPA Science Inventory

In 2010, a dramatic increase in the levels of total trihalomethane (THM) and the relative proportion of brominated species were observed in finished water at several Western Pennsylvania water utilities (PDW) using the Allegheny River as their raw water supply. An increase in br...

Potentiometric surface and specific conductance of the Sparta and Memphis aquifers in eastern Arkansas, 1995

USGS Publications Warehouse

Stanton, Gregory P.

1997-01-01

The Sparta and Memphis aquifers in eastern and south-central Arkansas are a major source of water for industrial, public supply, and agricultural uses. An estimated 240 million gallons per day was withdrawn from the Sparta and Memphis aquifers in 1995, an increase of about 17 million gallons per day from 1990. During the spring and early summer of 1995, the water level in the Sparta and Memphis aquifers was measured in 145 wells, the specific conductance of 101 ground-water samples collected from those aquifers was measured. Maps of areal distribution of potentiometric surface and specific conductance generated from these data reveal spatial trends in these parameters across the eastern and south-central Arkansas study area. The altitude of the potentiometric surface ranged from about 206 feet below sea level in Union County to about 307 feet above sea level in Saline County. The potentiometric surface of the Sparta and Memphis aquifers contains cones of depression descending below sea level in the central and southern portions of the study area, and a potentiometric high along the western study area boundary. Major recharge areas exhibit potentiometric highs greater than 200 feet above sea level and specific conductance values less than 200 microsiemens per centimeter, and generally are located in the outcrop/subcrop areas on the southern one-third of the western boundary and the northern portion of the study area. The regional direction of ground-water flow is from the north and west to the south and east, away from the outcrop and subcrop and northern regions, except near areas affected by intense ground-water withdrawals; such areas are manifested by large cones of depression centered in Columbia, Jefferson, and Union Counties. The cones of depression in adjoining Columbia and Union Counties are coalescing at or near sea level. The lowest water level measured was about 206 feet below sea level in Union County. Increased specific conductance values were measured in the areas of the cones of depression in Columbia and Union Counties. The cones of depression centered in Jefferson County coincides with an elongate area where ground water in the aquifer has low specific conductance. This area extends eastward from the outcrop/subcrop region of recharge. This extension of ground water with low specific conductance possibly indicates increased ground-water movement to the east-southeast from the outcrop/subcrop area induced by ground- water withdrawals in Jefferson County. Specific conductance increases markedly to the northeast and gradually to the south of this area. Long-term hydrographs of eight wells in the study areas, during the period 1970-1995, reveal water-level declines ranging from less than 0.5 foot per year in Phillips County to more than 2.0 feet per year in Union County. Water-level declines of greater than 1.5 feet per year generally are associated with the cones of depression centered in Columbia, Jefferson, and Union Counties.

Tree-Ring Dating of Extreme Lake Levels at the Subarctic?Boreal Interface

NASA Astrophysics Data System (ADS)

Bégin, Yves

2001-03-01

The dates of extreme water levels of two large lakes in northern Quebec have been recorded over the last century by ice scars on shoreline trees and sequences of reaction wood in shore trees tilted by wave erosion. Ice-scar chronologies indicate high water levels in spring, whereas tree-tilting by waves is caused by summer high waters. A major increase in both the amplitude and frequency of ice floods occurred in the 1930s. No such change was indicated by the tree-tilting chronologies, but wave erosion occurred in exceptionally rainy years. According to the modern record, spring lake-level rise is due to increased snowfalls since the 1930s. However, the absence of erosional marks in a large number of years since 1930 suggests a high frequency of low-water-level years resulting from dry conditions. Intercalary years with very large numbers of marked trees (e.g., 1935) indicate that the interannual range of summer lake levels has increased since the 1930s. Increased lake-flood frequency is postulated to be related to a slower expansion of arctic anticyclones, favoring the passage of cyclonic air masses over the area and resulting in abundant snowfall in early winter. Conditions in summer are due to the rate of weakening of the anticyclones controlling the position of the arctic front in summer. This position influences the path of the cyclonic air masses, which control summer precipitation and, consequently, summer lake levels in the area.

Quantifying the impact of bathymetric changes on the hydrological regimes in a large floodplain lake: Poyang Lake

NASA Astrophysics Data System (ADS)

Yao, Jing; Zhang, Qi; Ye, Xuchun; Zhang, Dan; Bai, Peng

2018-06-01

The hydrological regime of a lake is largely dependent on its bathymetry. A dramatic water level reduction has occurred in Poyang Lake in recent years, coinciding with significant bed erosion. Few studies have focused on the influence of bathymetric changes on the hydrological regime in such a complex river-lake floodplain system. This study combined hydrological data and a physically based hydrodynamic model to quantify the influence of the bathymetric changes (1998-2010) on the water level spatiotemporal distribution in Poyang Lake, based on a dry year (2006), a wet year (2010) and an average year (2000-2010). The following conclusions can be drawn from the results of this study: (1) The bed erosion of the northern outlet channel averaged 3 m, resulting in a decrease in the water level by 1.2-2 m in the northern channels (the most significantly influenced areas) and approximately 0.3 m in the central lake areas during low-level periods. The water levels below 16 m and 14 m were significantly affected during the rising period and recession period, respectively. The water level reduction was enhanced due to lower water levels. (2) The water surface profiles adjusted, and the rising and recession rates of the water level increased by 0.5-3.1 cm/d at the lake outlet. The bathymetric influence extended across the entire lake due to the emptying effect, resulting in a change in the water level distribution. The average annual outflow increased by 6.8%. (3) The bathymetric changes contributed approximately 14.4% to the extreme low water level in autumn 2006 and enhanced the drought in the dry season. This study quantified the impact of the bathymetric changes on the lake water levels, thereby providing a better understanding of the potential effects of continued sand mining operations and providing scientific explanations for the considerable variations in the hydrological regimes of Poyang Lake. Moreover, this study attempts to provide a reference for the assessment of similarly dramatic bathymetric changes in complex floodplain lakes.

Water Deficit Affected Flavonoid Accumulation by Regulating Hormone Metabolism in Scutellaria baicalensis Georgi Roots

PubMed Central

Wu, Chong; Chen, Shunqin; Wang, Zhouyong; Yang, Zhaochun; Qin, Shuangshuang; Huang, Luqi

2012-01-01

The content of flavonoids especially baicalin and baicalein determined the medical quality of Scutellaria baicalensis which is a Chinese traditional medicinal plant. Here, we investigated the mechanism responsible for the content and composition of flavonoids in S. baicalensis under water deficit condition. The transcription levels of several genes which are involved in flavonoid biosynthesis were stimulated by water deficit. Under water deficit condition, fifteen up-regulated proteins, three down-regulated proteins and other six proteins were detected by proteomic analysis. The identified proteins include three gibberellin (GA)- or indoleacetic acid (IAA)-related proteins. Decreased endogenous GAs level and increased IAA level were observed in leaves of S. baicalensis which was treated with water deficit. Exogenous application of GA or α-naphthalene acelic acid (NAA) to plants grown under water deficit conditions led to the increase of endogenous GAs and the decrease of IAA and flavonoids, respectively. When the synthesis pathway of GA or IAA in plants was inhibited by application with the inhibitors, flavonoid levels were recovered. These results indicate that water deficit affected flavonoid accumulation might through regulating hormone metabolism in S. baicalensis Georgi. PMID:23077481

Physical and Economic Impacts of Sea-Level Rise and Low Probability Flooding Events on Coastal Communities

PubMed Central

Prime, Thomas; Brown, Jennifer M.; Plater, Andrew J.

2015-01-01

Conventionally flood mapping typically includes only a static water level (e.g. peak of a storm tide) in coastal flood inundation events. Additional factors become increasingly important when increased water-level thresholds are met during the combination of a storm tide and increased mean sea level. This research incorporates factors such as wave overtopping and river flow in a range of flood inundation scenarios of future sea-level projections for a UK case study of Fleetwood, northwest England. With increasing mean sea level it is shown that wave overtopping and river forcing have an important bearing on the cost of coastal flood events. The method presented converts inundation maps into monetary cost. This research demonstrates that under scenarios of joint extreme surge-wave-river events the cost of flooding can be increased by up to a factor of 8 compared with an increase in extent of up to a factor of 3 relative to “surge alone” event. This is due to different areas being exposed to different flood hazards and areas with common hazard where flood waters combine non-linearly. This shows that relying simply on flood extent and volume can under-predict the actual economic impact felt by a coastal community. Additionally, the scenario inundation depths have been presented as “brick course” maps, which represent a new way of interpreting flood maps. This is primarily aimed at stakeholders to increase levels of engagement within the coastal community. PMID:25710497

Physical and economic impacts of sea-level rise and low probability flooding events on coastal communities.

PubMed

Prime, Thomas; Brown, Jennifer M; Plater, Andrew J

2015-01-01

Conventionally flood mapping typically includes only a static water level (e.g. peak of a storm tide) in coastal flood inundation events. Additional factors become increasingly important when increased water-level thresholds are met during the combination of a storm tide and increased mean sea level. This research incorporates factors such as wave overtopping and river flow in a range of flood inundation scenarios of future sea-level projections for a UK case study of Fleetwood, northwest England. With increasing mean sea level it is shown that wave overtopping and river forcing have an important bearing on the cost of coastal flood events. The method presented converts inundation maps into monetary cost. This research demonstrates that under scenarios of joint extreme surge-wave-river events the cost of flooding can be increased by up to a factor of 8 compared with an increase in extent of up to a factor of 3 relative to "surge alone" event. This is due to different areas being exposed to different flood hazards and areas with common hazard where flood waters combine non-linearly. This shows that relying simply on flood extent and volume can under-predict the actual economic impact felt by a coastal community. Additionally, the scenario inundation depths have been presented as "brick course" maps, which represent a new way of interpreting flood maps. This is primarily aimed at stakeholders to increase levels of engagement within the coastal community.

The effect of balneotherapy on C-reactive protein, serum cholesterol, triglyceride, total antioxidant status and HSP-60 levels.

PubMed

Oláh, Mihály; Koncz, Agnes; Fehér, Judit; Kálmánczhey, Judit; Oláh, Csaba; Balogh, Sándor; Nagy, György; Bender, Tamás

2010-05-01

An increasing body of evidence substantiating the effectiveness of balneotherapy has accumulated during recent decades. In the present study, 42 ambulatory patients (23 males and 19 females, mean age 59.5 years) with degenerative musculoskeletal disease were randomised into one of two groups-bathing in tap water or in mineral water at the same temperature-and subjected to 30-min balneotherapy sessions on 15 occasions. Study parameters comprised serum levels of sensitised C-reactive protein (CRP), plasma lipids, heat shock protein (HSP-60) and total antioxidant status (TAS). In both groups, CRP levels followed a decreasing tendency, which still persisted 3 months later. At 3 months after balneotherapy, serum cholesterol levels were still decreasing in patients who had used medicinal water, but exhibited a trend towards an increase in the control group. Triglyceride levels followed a decreasing trend in both patient groups. TAS showed a declining tendency in both groups. No changes of HSP-60 levels were observed in either group. Balneotherapy with the thermal water from Hajdúszoboszló spa had a more pronounced physiological effect compared to that seen in the control group treated with tap water in a 3 month period.

The effect of water stress on super-high- density 'Koroneiki' olive oil quality.

PubMed

Dag, Arnon; Naor, Amos; Ben-Gal, Alon; Harlev, Guy; Zipori, Isaac; Schneider, Doron; Birger, Reuven; Peres, Moti; Gal, Yoni; Kerem, Zohar

2015-08-15

Over the last two decades, the area of cultivated super-high-density olive orchards has increased rapidly. Water stress is an important tool in super-high-density orchards to reduce tree growth and promote suitability for overhead mechanical harvesters. Little is known regarding the effect of water stress in super-high-density orchards on oil quality parameters. In this study the effect of irrigation rate on oil quality parameters was evaluated in a six-year-old super-high-density 'Koreneiki' olive orchard for five consecutive seasons. Five water status levels, determined by irrigating in order to maintain various midday stem water potential threshold values (-1.5, -2, -2.5, -3 and -4 MPa), were applied during the oil accumulation stage. The MUFA/PUFA ratio and free fatty acid content generally decreased as a function of increasing tree water stress. In most seasons a reduction in polyphenols was found with decreasing irrigation level. Peroxide value was not affected by the water stress level. The present study demonstrates that limiting irrigation and exposure of olive trees to water stress in a super-high-density orchard lowers free fatty acid content and therefore benefits oil quality. However, the decreased MUFA/PUFA ratio and the reduction in polyphenol content that were also found under increased water stress negatively influence oil quality. © 2014 Society of Chemical Industry.

Groundwater-level trends and implications for sustainable water use in the Kabul Basin, Afghanistan

USGS Publications Warehouse

Mack, Thomas J.; Chornack, Michael P.; Taher, Mohammad R.

2013-01-01

The Kabul Basin, which includes the city of Kabul, Afghanistan, with a population of approximately 4 million, has several Afghan, United States, and international military installations that depend on groundwater resources for a potable water supply. This study examined groundwater levels in the Kabul Basin from 2004 to 2012. Groundwater levels have increased slightly in rural areas of the Kabul Basin as a result of normal precipitation after the drought of the early 2000s. However, groundwater levels have decreased in the city of Kabul due to increasing water use in an area with limited recharge. The rate of groundwater-level decrease in the city is greater for the 2008–2012 period (1.5 meters per year (m/yr) on average) than for the 2004–2008 period (0–0.7 m/yr on average). The analysis, which is corroborated by groundwater-flow modeling and a non-governmental organization decision-support model, identified groundwater-level decreases and associated implications for groundwater sustainability in the city of Kabul. Military installations in the city of Kabul (the Central Kabul subbasin) are likely to face water management challenges resulting from long-term groundwater sustainability concerns, such as the potential drying of shallow water-supply wells. Installations in the northern part of the Kabul Basin may have fewer issues with long-term water sustainability. Groundwater-level monitoring and groundwater-flow simulation can be valuable tools for assessing groundwater management options to improve the sustainability of water resources in the Kabul Basin.

Forecasting the impact of storm waves and sea-level rise on Midway Atoll and Laysan Island within the Papahānaumokuākea Marine National Monument—a comparison of passive versus dynamic inundation models

USGS Publications Warehouse

Storlazzi, Curt D.; Berkowitz, Paul; Reynolds, Michelle H.; Logan, Joshua B.

2013-01-01

Two inundation events in 2011 underscored the potential for elevated water levels to damage infrastructure and affect terrestrial ecosystems on the low-lying Northwestern Hawaiian Islands in the Papahānaumokuākea Marine National Monument. The goal of this study was to compare passive "bathtub" inundation models based on geographic information systems (GIS) to those that include dynamic water levels caused by wave-induced set-up and run-up for two end-member island morphologies: Midway, a classic atoll with islands on the shallow (2-8 m) atoll rim and a deep, central lagoon; and Laysan, which is characterized by a deep (20-30 m) atoll rim and an island at the center of the atoll. Vulnerability to elevated water levels was assessed using hindcast wind and wave data to drive coupled physics-based numerical wave, current, and water-level models for the atolls. The resulting model data were then used to compute run-up elevations using a parametric run-up equation under both present conditions and future sea-level-rise scenarios. In both geomorphologies, wave heights and wavelengths adjacent to the island shorelines increased more than three times and four times, respectively, with increasing values of sea-level rise, as more deep-water wave energy could propagate over the atoll rim and larger wind-driven waves could develop on the atoll. Although these increases in water depth resulted in decreased set-up along the islands’ shorelines, the larger wave heights and longer wavelengths due to sea-level rise increased the resulting wave-induced run-up. Run-up values were spatially heterogeneous and dependent on the direction of incident wave direction, bathymetry, and island configuration. Island inundation was modeled to increase substantially when wave-driven effects were included, suggesting that inundation and impacts to infrastructure and terrestrial habitats will occur at lower values of predicted sea-level rise, and thus sooner in the 21st century, than suggested by passive GIS-based "bathtub" inundation models. Lastly, observations and the modeling results suggest that classic atolls with islands on a shallow atoll rim are more susceptible to the combined effects of sea-level rise and wave-driven inundation than atolls characterized by a deep atoll rim.

Wetland Resiliency: How does multi-year water table level decline and recovery influence carbon dioxide and methane fluxes?

NASA Astrophysics Data System (ADS)

Pugh, C.; Reed, D. E.; Desai, A. R.; Sulman, B. N.

2016-12-01

Wetlands play a disproportionately large role in the global carbon budget, and individual wetlands can fluctuate between carbon sinks and sources depending on factors such as hydrology, biogeochemistry, and land use. Although much research has been done on wetland biogeochemical cycles, there is a lack of experimental evidence concerning how changes in wetland hydrology influence these cycles over interannual timescales. Over a seven-year period, Sulman et al. (2009) found that a drought-induced declining water table at a shrub wetland in northern Wisconsin coincided with increased ecosystem respiration (ER) and gross ecosystem productivity (GEP) (Sulman et al. 2009). Since then, however, the average water table level at this site has begun to increase, thus allowing a unique opportunity to explore how wetland carbon storage is impacted by water table recovery. With the addition of three more years of eddy covariance observations post recovery and new methane flux observations, we found that water table level no longer had a significant correlation with GEP, ER, or methane flux. Air temperature, however, had a strong correlation with all three. Average methane flux stayed relatively constant under 14 °C, before increasing an order of magnitude from 3.7 nmol m-2 s-1 in April to 36 nmol m-2 s-1 in July. These results suggest that, over decadal timescales, temperature, rather than water level, is a stronger limiting factor for both aerobic and anaerobic respiration in shrub fen wetlands. Wetlands play a disproportionately large role in the global carbon budget, and individual wetlands can fluctuate between carbon sinks and sources depending on factors such as hydrology, biogeochemistry, and land use. Although much research has been done on wetland biogeochemical cycles, there is a lack of experimental evidence concerning how changes in wetland hydrology influence these cycles over interannual timescales. Over a seven-year period, Sulman et al. (2009) found that a drought-induced declining water table at a shrub wetland in northern Wisconsin coincided with increased ecosystem respiration (ER) and gross ecosystem productivity (GEP) (Sulman et al. 2009). Since then, however, the average water table level at this site has begun to increase, thus allowing a unique opportunity to explore how wetland carbon storage is impacted by water table recovery. With the addition of three more years of eddy covariance observations post recovery and new methane flux observations, we found that water table level no longer had a significant correlation with GEP, ER, or methane flux. Air temperature, however, had a strong correlation with all three. Average methane flux stayed relatively constant under 14 °C, before increasing an order of magnitude from 3.7 nmol m-2 s-1 in April to 36 nmol m-2 s-1 in July. These results suggest that, over decadal timescales, temperature, rather than water level, is a stronger limiting factor for both aerobic and anaerobic respiration in shrub fen wetlands.

Association between water fluoride and the level of children's intelligence: a dose-response meta-analysis.

PubMed

Duan, Q; Jiao, J; Chen, X; Wang, X

2018-01-01

Higher fluoride concentrations in water have inconsistently been associated with the levels of intelligence in children. The following study summarizes the available evidence regarding the strength of association between fluoridated water and children's intelligence. Meta-analysis. PubMed, Embase, and Cochrane Library databases were systematically analyzed from November 2016. Observational studies that have reported on intelligence levels in relation to high and low water fluoride contents, with 95% confidence intervals (CIs) were included. Further, the results were pooled using inverse variance methods. The correlation between water fluoride concentration and intelligence level was assessed by a dose-response meta-analysis. Twenty-six studies reporting data on 7258 children were included. The summary results indicated that high water fluoride exposure was associated with lower intelligence levels (standardized mean difference : -0.52; 95% CI: -0.62 to -0.42; P < 0.001). The findings from subgroup analyses were consistent with those from overall analysis. The dose-response meta-analysis suggested a significant association between water fluoride dosage and intelligence (P < 0.001), while increased water fluoride exposure was associated with reduced intelligence levels. Greater exposure to high levels of fluoride in water was significantly associated with reduced levels of intelligence in children. Therefore, water quality and exposure to fluoride in water should be controlled in areas with high fluoride levels in water. Copyright © 2017. Published by Elsevier Ltd.

Effect of the Ratio of Raw Material Components on the Physico-chemical Characteristics of Emulsion-type Pork Sausages

PubMed Central

Jin, Sang-Keun; Ha, So-Ra; Hur, Sun-Jin; Choi, Jung-Seok

2016-01-01

This study was conducted to investigate the effects of raw material ratio on the physicochemical characteristics of emulsion-type pork sausages. Experiment design was divided into 12 treatments, based on protein level (P), fat level (3P, 3.5P, and 4P), and water level (4P+10, 4P+15, 4P+20, and 4P+25). The pH and shear force values were significantly higher in T7 (3.5P fat and 4P+20 water) than those of other treatments. The lightness and redness were greatly reduced by increasing the quantity of water. The treatments containing 3P fat and 4P+20 water had the highest values of cohesiveness, springiness, gumminess, and chewiness. On the whole, when the protein (P) and fat (3P, 3.5P, 4P) levels were fixed, an increase over the appropriate moisture level deteriorated many physicochemical characteristics. PMID:26732451

Observations and estimates of wave-driven water level extremes at the Marshall Islands

NASA Astrophysics Data System (ADS)

Merrifield, M. A.; Becker, J. M.; Ford, M.; Yao, Y.

2014-10-01

Wave-driven extreme water levels are examined for coastlines protected by fringing reefs using field observations obtained in the Republic of the Marshall Islands. The 2% exceedence water level near the shoreline due to waves is estimated empirically for the study sites from breaking wave height at the outer reef and by combining separate contributions from setup, sea and swell, and infragravity waves, which are estimated based on breaking wave height and water level over the reef flat. Although each component exhibits a tidal dependence, they sum to yield a 2% exceedence level that does not. A hindcast based on the breaking wave height parameterization is used to assess factors leading to flooding at Roi-Namur caused by an energetic swell event during December 2008. Extreme water levels similar to December 2008 are projected to increase significantly with rising sea level as more wave and tide events combine to exceed inundation threshold levels.

Groundwater response to the 2014 pulse flow in the Colorado River Delta

USGS Publications Warehouse

Kennedy, Jeffrey; Rodriguez-Burgueno, Eliana; Ramirez-Hernandez, Jorge

2017-01-01

During the March-May 2014 Colorado River Delta pulse flow, approximately 102 × 106 m3 (82,000 acre-feet) of water was released into the channel at Morelos Dam, with additional releases further downstream. The majority of pulse flow water infiltrated and recharged the regional aquifer. Using groundwater-level and microgravity data we mapped the spatial and temporal distribution of changes in aquifer storage associated with pulse flow. Surface-water losses to infiltration were greatest around the Southerly International Boundary, where a lowered groundwater level owing to nearby pumping created increased storage potential as compared to other areas with shallower groundwater. Groundwater levels were elevated for several months after the pulse flow but had largely returned to pre-pulse levels by fall 2014. Elevated groundwater levels in the limitrophe (border) reach extended about 2 km to the east around the midway point between the Northerly and Southerly International Boundaries, and about 4 km to the east at the southern end. In the southern part of the delta, although total streamflow in the channel was less due to upstream infiltration, augmented deliveries through irrigation canals and possible irrigation return flows created sustained increases in groundwater levels during summer 2014. Results show that elevated groundwater levels and increases in groundwater storage were relatively short lived (confined to calendar year 2014), and that depressed water levels associated with groundwater pumping around San Luis, Arizona and San Luis Rio Colorado, Sonora cause large, unavoidable infiltration losses of in-channel water to groundwater in the vicinity.

Simulation and assessment of groundwater flow and groundwater and surface-water exchanges in lakes of the northeast Twin Cities Metropolitan Area, Minnesota, 2003 through 2013: Chapter B of Water levels and groundwater and surface-water exchanges in lakes of the northeast Twin Cities Metropolitan Area, Minnesota, 2002 through 2015

USGS Publications Warehouse

Jones, Perry M.; Roth, Jason L.; Trost, Jared J.; Christenson, Catherine A.; Diekoff, Aliesha L.; Erickson, Melinda L.

2017-09-05

Water levels during 2003 through 2013 were less than mean water levels for the period 1925–2013 for several lakes in the northeast Twin Cities Metropolitan Area in Minnesota. Previous periods of low lake-water levels generally were correlated with periods with less than mean precipitation. Increases in groundwater withdrawals and land-use changes have brought into question whether or not recent (2003–13) lake-water-level declines are solely caused by decreases in precipitation. A thorough understanding of groundwater and surface-water exchanges was needed to assess the effect of water-management decisions on lake-water levels. To address this need, the U.S. Geological Survey, in cooperation with the Metropolitan Council and the Minnesota Department of Health, developed and calibrated a three-dimensional, steady-state groundwater-flow model representing 2003–13 mean hydrologic conditions to assess groundwater and lake-water exchanges, and the effects of groundwater withdrawals and precipitation on water levels of 96 lakes in the northeast Twin Cities Metropolitan Area.Lake-water budgets for the calibrated groundwater-flow model indicated that groundwater is flowing into lakes in the northeast Twin Cities Metropolitan Area and lakes are providing water to underlying aquifers. Lake-water outflow to the simulated groundwater system was a major outflow component for Big Marine Lake, Lake Elmo, Snail Lake, and White Bear Lake, accounting for 45 to 64 percent of the total outflows from the lakes. Evaporation and transpiration from the lake surface ranged from 19 to 52 percent of the total outflow from the four lakes. Groundwater withdrawals and precipitation were varied from the 2003‒13 mean values used in the calibrated model (30-percent changes in groundwater withdrawals and 5-percent changes in precipitation) for hypothetical scenarios to assess the effects of groundwater withdrawals and precipitation on water budgets and levels in Big Marine Lake, Snail Lake, and White Bear Lake. Simulated lake-water levels and budgets for Snail Lake and White Bear Lake were affected by 30-percent changes in groundwater withdrawals and 5-percent changes in precipitation in the area, whereas the water level in Big Marine Lake was mainly affected by 5-percent precipitation changes. The effects of groundwater withdrawals on the lake-water levels depend on the number of wells and amount of withdrawals from wells near the lakes. Although lake-water levels are sensitive to precipitation changes, increases in groundwater withdrawals during dry periods exacerbate lake-water level declines. The calibrated, groundwater-flow model is a tool that water-resources managers can use to address future water management issues in the northeast Twin Cities Metropolitan Area.

Regional Water Table (1998) and Ground-Water-Level Changes in the Mojave River, and the Morongo Ground-Water Basins, San Bernardino County, California

USGS Publications Warehouse

Smith, Gregory A.; Pimentel, M. Isabel

2000-01-01

The Mojave River and the Morongo ground-water basins are in the southwestern part of the Mojave Desert in southern California. Ground water from these basins supplies a major part of the water requirements for the region. The rapid and continuous population growth in this area has resulted in ever-increasing demands on local ground-water resources. The continuing collection and interpretation of ground-water data helps local water districts, military bases, and private citizens gain a better understanding of the ground-water systems and, consequently, water availability. During 1998 the U.S. Geological Survey and other agencies made approximately 2,370 water-level measurements in the Mojave River and the Morongo ground-water basins. These data document recent conditions and changes in ground-water levels. A water-level contour map was drawn using data from 450 wells, providing coverage for most of both basins. Twenty-three hydrographs show long-term (as much as 70 years) water-level trends throughout the basins. To help show effects of late seasonal recharge along the Mojave River, 14 short-term (13 years) hydrographs were created. A water-level change map was compiled to enable comparison of 1996 and 1998 water levels. The Mojave River and the Morongo ground-water basins had little change in water levels between 1996 and 1998 - with the exception of the areas of the Yucca Valley affected by artificial recharge. Other water-level changes were localized and reflected pumping or measurements made before seasonal recharge. Three areas of perched ground water were identified: El Mirage Lake (dry), Adelanto, and Lucerne Valley.

Statistical analysis of lake levels and field study of groundwater and surface-water exchanges in the northeast Twin Cities Metropolitan Area, Minnesota, 2002 through 2015: Chapter A of Water levels and groundwater and surface-water exchanges in lakes of the northeast Twin Cities Metropolitan Area, Minnesota, 2002 through 2015

USGS Publications Warehouse

Jones, Perry M.; Trost, Jared J.; Diekoff, Aliesha L.; Rosenberry, Donald O.; White, Eric A.; Erickson, Melinda L.; Morel, Daniel L.; Heck, Jessica M.

2016-10-19

Water levels declined from 2003 to 2011 in many lakes in Ramsey and Washington Counties in the northeast Twin Cities Metropolitan Area, Minnesota; however, water levels in other northeast Twin Cities Metropolitan Area lakes increased during the same period. Groundwater and surface-water exchanges can be important in determining lake levels where these exchanges are an important component of the water budget of a lake. An understanding of groundwater and surface-water exchanges in the northeast Twin Cities Metropolitan Area has been limited by the lack of hydrologic data. The U.S. Geological Survey, in cooperation with the Metropolitan Council and Minnesota Department of Health, completed a field and statistical study assessing lake-water levels and regional and local groundwater and surface-water exchanges near northeast Twin Cities Metropolitan Area lakes. This report documents the analysis of collected hydrologic, water-quality, and geophysical data; and existing hydrologic and geologic data to (1) assess the effect of physical setting and climate on lake-level fluctuations of selected lakes, (2) estimate potential percentages of surface-water contributions to well water across the northeast Twin Cities Metropolitan Area, (3) estimate general ages for waters extracted from the wells, and (4) assess groundwater inflow to lakes and lake-water outflow to aquifers downgradient from White Bear Lake. Statistical analyses of lake levels during short-term (2002–10) and long-term (1925–2014) periods were completed to help understand lake-level changes across the northeast Twin Cities Metropolitan Area. Comparison of 2002–10 lake levels to several landscape and geologic characteristics explained variability in lake-level changes for 96 northeast Twin Cities Metropolitan Area lakes. Application of several statistical methods determined that (1) closed-basin lakes (without an active outlet) had larger lake-level declines than flow-through lakes with an outlet; (2) closed-basin lake-level changes reflected groundwater-level changes in the Quaternary, Prairie du Chien, and Jordan aquifers; (3) the installation of outlet-control structures, such as culverts and weirs, resulted in smaller multiyear lake-level changes than lakes without outlet-control structures; (4) water levels in lakes primarily overlying Superior Lobe deposits were significantly more variable than lakes primarily overlying Des Moines Lobe deposits; (5) lake-level declines were larger with increasing mean lake-level elevation; and (6) the frequency of some of these characteristics varies by landscape position. Flow-through lakes and lakes with outlet-control structures were more common in watersheds with more than 50 percent urban development compared to watersheds with less than 50 percent urban development. A comparison of two 35-year periods during 1925–2014 revealed that variability of annual mean lake levels in flow-through lakes increased when annual precipitation totals were more variable, whereas variability of annual mean lake levels in closed-basin lakes had the opposite pattern, being more variable when annual precipitation totals were less variable. Oxygen-18/oxygen-16 and hydrogen-2/hydrogen-1 ratios for water samples from 40 wells indicated the well water was a mixture of surface water and groundwater in 31 wells, whereas ratios from water sampled from 9 other wells indicated that water from these wells receive no surface-water contribution. Of the 31 wells with a mixture of surface water and groundwater, 11 were downgradient from White Bear Lake, likely receiving water from deeper parts of the lake. Age dating of water samples from wells indicated that the age of water in the Prairie du Chien and Jordan aquifers can vary widely across the northeast Twin Cities Metropolitan Area. Estimated ages of recharge for 9 of the 40 wells sampled for chlorofluorocarbon concentrations ranged widely from the early 1940s to mid-1970s. The wide range in estimated ages of recharge may have resulted from the wide range in the open-interval lengths and depths for the wells.Results from stable isotope analyses of water samples, lake-sediment coring, continuous seismic-reflection profiling, and water-level and flow monitoring indicated that there is groundwater inflow from nearshore sites and lake-water outflow from deep-water sites in White Bear Lake. Continuous seismic-reflection profiling indicated that deep sections of White Bear, Pleasant, Turtle, and Big Marine Lakes have few trapped gases and little organic material, which indicates where groundwater and lake-water exchanges are more likely. Water-level differences between White Bear Lake and piezometer and seepage measurements in deep waters of the lake indicate that groundwater and lake-water exchange is happening in deep waters, predominantly downgradient from the lake and into the lake sediment. Seepage fluxes measured in the nearshore sites of White Bear Lake generally were higher than seepage fluxes measured in the deep-water sites, which indicates that groundwater-inflow rates at most of the nearshore sites are higher than lake-water outflow from the deep-water sites.

Changes in Breath Trihalomethane Levels Resulting from Household Water-Use Activities

PubMed Central

Gordon, Sydney M.; Brinkman, Marielle C.; Ashley, David L.; Blount, Benjamin C.; Lyu, Christopher; Masters, John; Singer, Philip C.

2006-01-01

Common household water-use activities such as showering, bathing, drinking, and washing clothes or dishes are potentially important contributors to individual exposure to trihalomethanes (THMs), the major class of disinfection by-products of water treated with chlorine. Previous studies have focused on showering or bathing activities. In this study, we selected 12 common water-use activities and determined which may lead to the greatest THM exposures and result in the greatest increase in the internal dose. Seven subjects performed the various water-use activities in two residences served by water utilities with relatively high and moderate total THM levels. To maintain a consistent exposure environment, the activities, exposure times, air exchange rates, water flows, water temperatures, and extraneous THM emissions to the indoor air were carefully controlled. Water, indoor air, blood, and exhaled-breath samples were collected during each exposure session for each activity, in accordance with a strict, well-defined protocol. Although showering (for 10 min) and bathing (for 14 min), as well as machine washing of clothes and opening mechanical dishwashers at the end of the cycle, resulted in substantial increases in indoor air chloroform concentrations, only showering and bathing caused significant increases in the breath chloroform levels. In the case of bromodichloromethane (BDCM), only bathing yielded a significantly higher air level in relation to the preexposure concentration. For chloroform from showering, strong correlations were observed for indoor air and exhaled breath, blood and exhaled breath, indoor air and blood, and tap water and blood. Only water and breath, and blood and breath were significantly associated for chloroform from bathing. For BDCM, significant correlations were obtained for blood and air, and blood and water from showering. Neither dibromochloromethane nor bromoform gave measurable breath concentrations for any of the activities investigated because of their much lower tap-water concentrations. Future studies will address the effects that changes in these common water-use activities may have on exposure. PMID:16581538

Death receptor and mitochondria-mediated hepatocyte apoptosis underlies liver dysfunction in rats exposed to organic pollutants from drinking water

PubMed Central

Yang, Guanghong; Zhou, Zhiwei; Cen, Yanli; Gui, Xiaolin; Zeng, Qibing; Ao, Yunxia; Li, Qian; Wang, Shiran; Li, Jun; Zhang, Aihua

2015-01-01

Persistent organic pollutants in drinking water impose a substantial risk to the health of human beings, but the evidence for liver toxic effect and the underlying mechanism is scarce. This study aimed to examine the liver toxicity and elucidate the molecular mechanism of organic pollutants in drinking water in normal human liver cell line L02 cells and rats. The data showed that organic extraction from drinking water remarkably impaired rat liver function, evident from the increase in the serum level of alanine aminotransferase, aspartate aminotransferase, and cholinesterase, and decrease in the serum level of total protein and albumin. Organic extraction dose-dependently induced apoptotic cell death in rat liver and L02 cells. Administration of rats with organic extraction promoted death receptor signaling pathway through the increase in gene and protein expression level of Fas and FasL. Treatment of rats with organic extraction also induced mitochondria-mediated apoptosis via increasing the expression level of proapoptotic protein, Bax, but decreasing the expression level of antiapoptotic protein, Bcl-2, resulting in an upregulation of cytochrome c and activation of caspase cascade at both transcriptional and post-transcriptional levels. Moreover, organic extraction enhanced rat liver glutathione S-transferases activity and reactive oxygen species generation, and upregulated aryl hydrocarbon receptor and glutathione S-transferase A1 at both transcriptional and translational levels. Collectively, the results indicate that organic extraction from drinking water impairs liver function, with the involvement of death receptor and mitochondria-mediated apoptosis in rats. The results provide evidence and molecular mechanisms for organic pollutants in drinking water-induced liver dysfunction, which may help prevent and treat organic extraction-induced liver injury. PMID:26316710

Death receptor and mitochondria-mediated hepatocyte apoptosis underlies liver dysfunction in rats exposed to organic pollutants from drinking water.

PubMed

Yang, Guanghong; Zhou, Zhiwei; Cen, Yanli; Gui, Xiaolin; Zeng, Qibing; Ao, Yunxia; Li, Qian; Wang, Shiran; Li, Jun; Zhang, Aihua

2015-01-01

Persistent organic pollutants in drinking water impose a substantial risk to the health of human beings, but the evidence for liver toxic effect and the underlying mechanism is scarce. This study aimed to examine the liver toxicity and elucidate the molecular mechanism of organic pollutants in drinking water in normal human liver cell line L02 cells and rats. The data showed that organic extraction from drinking water remarkably impaired rat liver function, evident from the increase in the serum level of alanine aminotransferase, aspartate aminotransferase, and cholinesterase, and decrease in the serum level of total protein and albumin. Organic extraction dose-dependently induced apoptotic cell death in rat liver and L02 cells. Administration of rats with organic extraction promoted death receptor signaling pathway through the increase in gene and protein expression level of Fas and FasL. Treatment of rats with organic extraction also induced mitochondria-mediated apoptosis via increasing the expression level of proapoptotic protein, Bax, but decreasing the expression level of antiapoptotic protein, Bcl-2, resulting in an upregulation of cytochrome c and activation of caspase cascade at both transcriptional and post-transcriptional levels. Moreover, organic extraction enhanced rat liver glutathione S-transferases activity and reactive oxygen species generation, and upregulated aryl hydrocarbon receptor and glutathione S-transferase A1 at both transcriptional and translational levels. Collectively, the results indicate that organic extraction from drinking water impairs liver function, with the involvement of death receptor and mitochondria-mediated apoptosis in rats. The results provide evidence and molecular mechanisms for organic pollutants in drinking water-induced liver dysfunction, which may help prevent and treat organic extraction-induced liver injury.

Extensive Liquid Meltwater Storage in Firn Within the Greenland Ice Sheet

NASA Technical Reports Server (NTRS)

Forster, Richard R.; Box, Jason E.; vandenBroeke, Michael R.; Miege, Clement; Burgess, Evan W.; vanAngelen, Jan H.; Lenaerts, Jan T. M.; Koenig, Lora S.; Paden, John; Lewis, Cameron;

Evaluating confidence in the impact of regulatory nutrient reduction and assessing the competing impact of climate change

NASA Astrophysics Data System (ADS)

Irby, I.; Friedrichs, M. A. M.

2017-12-01

Human impacts on the Chesapeake Bay through increased nutrient run-off as a result of land-use change, urbanization, and industrialization, have resulted in a degradation of water quality over the last half-century. These direct impacts, compounded with human-induced climate changes such as warming, rising sea level, and changes in precipitation, have elevated the conversation surrounding the future of the Bay's water quality. As a result, in 2010, a Total Maximum Daily Load (TMDL) was established for the Chesapeake Bay that limited nutrient and sediment input in an effort to increase dissolved oxygen. This research utilizes a multiple model approach to evaluate confidence in the estuarine water quality modeling portion of the TMDL. One of the models is then used to assess the potential impact climate change may have on the success of currently mandated nutrient reduction levels in 2050. Results demonstrate that although the models examined differ structurally and in biogeochemical complexity, they project a similar attainment of regulatory water quality standards after nutrient reduction, while also establishing that meeting water quality standards is relatively independent of hydrologic conditions. By developing a Confidence Index, this research identifies the locations and causes of greatest uncertainty in modeled projections of water quality. Although there are specific locations and times where the models disagree, this research lends an increased degree of confidence in the appropriateness of the TMDL levels and in the general impact nutrient reductions will have on Chesapeake Bay water quality under current environmental conditions. However, when examining the potential impacts of climate change, this research shows that the combined impacts of increasing temperature, sea level, and river flow negatively affect dissolved oxygen throughout the Chesapeake Bay and impact progress towards meeting the water quality standards associated with the TMDL with increased temperature as the primary culprit. These results, having been continually shared with the regulatory TMDL modelers, will aid in the decision making for the 2017 TMDL Mid-Point Assessment.

A comparison of observed extreme water levels at the German Bight elaborated through an extreme value analysis (EVA) with extremes derived from a regionally coupled ocean-atmospheric climate model (MPI-OM)

NASA Astrophysics Data System (ADS)

Möller, Jens; Heinrich, Hartmut

2017-04-01

As a consequence of climate change atmospheric and oceanographic extremes and their potential impacts on coastal regions are of growing concern for governmental authorities responsible for the transportation infrastructure. Highest risks for shipping as well as for rail and road traffic originate from combined effects of extremes of storm surges and heavy rainfall which sometimes lead to insufficient dewatering of inland waterways. The German Ministry of Transport and digital Infrastructure therefore has tasked its Network of Experts to investigate the possible evolutions of extreme threats for low lands and especially for Kiel Canal, which is an important shortcut for shipping between the North and Baltic Seas. In this study we present results of a comparison of an Extreme Value Analysis (EVA) carried out on gauge observations and values derived from a coupled Regional Ocean-Atmosphere Climate Model (MPI-OM). High water levels at the coasts of the North and Baltic Seas are one of the most important hazards which increase the risk of flooding of the low-lying land and prevents such areas from an adequate dewatering. In this study changes in the intensity (magnitude of the extremes) and duration of extreme water levels (above a selected threshold) are investigated for several gauge stations with data partly reaching back to 1843. Different methods are used for the extreme value statistics, (1) a stationary general Pareto distribution (GPD) model as well as (2) an instationary statistical model for better reproduction of the impact of climate change. Most gauge stations show an increase of the mean water level of about 1-2 mm/year, with a stronger increase of the highest water levels and a decrease (or lower increase) of the lowest water levels. Also, the duration of possible dewatering time intervals for the Kiel-Canal was analysed. The results for the historical gauge station observations are compared to the statistics of modelled water levels from the coupled atmosphere-ocean climate model MPI-OM for the time interval from 1951 to 2000. We demonstrate that for high water levels the observations and MPI-OM results are in good agreement, and we provide an estimate on the decreasing dewatering potential for Kiel Canal until the end of the 21st century.

Deep-convection events foster carbonate ion reduction in deep coral reefs

NASA Astrophysics Data System (ADS)

Perez, Fiz F.; Fontela, Marcos; Garcia-Ibañez, Maribel I.; Lherminier, Pascale; Zunino, Patricia; de la Paz, Mercedes; Padín, Xose A.; Alonso-Pérez, Fernando; Velo, Anton; Guallart, Elisa F.; Mercier, Herle

2017-04-01

Since millennial times, water mass circulation and deep-convection events have been transforming warm upper waters at high latitudes into cold and well-oxygenated deep waters. These processes have filled the deep North Atlantic Ocean with waters moderately saturated in calcium carbonate, thus promoting the growth of stony corals, which are hotspots of biodiversity. During the Anthropocene, the meridional circulation has been conveying cumulative amounts of more acidified waters with lower calcium carbonate saturation levels due to the incorporation of anthropogenic carbon dioxide, with very harsh conditions for deep cold-water corals projected by 2100. We evaluate the diminution of calcium carbonate saturation levels (aragonite form) due to the increase in anthropogenic carbon dioxide during the last two decades (2002-2016). We observe a strong decrease in the aragonite saturation levels concomitant with the reduction in the volume transport of aragonite-saturated waters. We estimate a 30-35% reduction in the transport of ion carbonate excess over the saturation levels with respect to the natural carbon cycle for the period 2002-2016. This reduction is associated with an increase in the downward transport of hydrogen ions. We also observe a heaving of the aragonite saturation horizons during the last 25 years, which is estimated at 6 m year-1 for the deep waters and 12-14 m year-1 for the intermediated waters. The harsh winters of 2015 and 2016 have fostered the fast addition of more acidified water into the lower layers of the North Atlantic through deep-convection events. In the future scenario of 2oC warming, the anthropogenic carbon dioxide in the water column would be double than today and the associated transport of hydrogen ions towards the bottom water would reduce the aragonite saturation levels to 60-80% with respect to preindustrial levels. This reduction in the aragonite saturation levels would suppose a strong diminution of the North Atlantic habitats where stony corals will be able to inhabit.

Sensitivity of Water-Energy Nexus to dam operation: A Water-Energy Productivity concept.

PubMed

Basheer, Mohammed; Elagib, Nadir Ahmed

2018-03-01

Understanding and modelling the complex nature of interlinkages between water and energy are essential for efficient use of the two resources. Hydropower storage dams represent an interesting example of the water-energy interdependencies since they are often multipurpose. The concept of Water-Energy Productivity (WEP), defined as the amount of energy produced per unit of water lost in the process, is introduced in this study to illustrate the relationship between energy generation and water losses by examining the sensitivity of the Water-Energy Nexus (WEN) to changing dam operation policy. This concept is demonstrated by developing a water allocation model of the White Nile in Sudan, including Jebel Aulia Dam (JAD), using a general river and reservoir simulation software called RiverWare. A number of 77 operation scenarios of JAD are examined for 30 hydrologic years (1980-2009), considering reducing the Full Supply Level (FSL) gradually from its current value to the minimum possible value, increasing the Minimum Operating Level (MOL) gradually to the maximum possible level, and operating the dam at a Constant Operating Level (COL). The results show that raising the operating level does not necessarily increase the WEP. In comparison to the current policy, the analysis shows that a maximum WEP of 32.6GWh/BCM (GWh/Billion Cubic Meters) would be reached by raising the MOL to 375masl (meters above sea level), resulting in an increase in average annual energy generation to 164.6GWh (+18.1%) at the expense of an annual water loss of 5.05BCM (+12.7%). Even though this operation policy results in a more efficient water use compared to the original operation policy, a basin-wide assessment that includes all hydropower storage dams in the Nile basin should be conducted to decide on where and how much energy should be generated. The present analysis and future examination of the multi-dimensions of the WEN in the context of dam operation are imperative to improve the decision making in the quest for efficient resource use and management. Copyright © 2017 Elsevier B.V. All rights reserved.

Water and the environment: a natural resource or a limited luxury?

PubMed

Leder, Karin; Sinclair, Martha I; McNeil, John J

The risk of contamination of drinking water supplies with microbial pathogens is minimised by modern approaches to water management, but continues to be the major public health concern. Chemical contaminants usually pose little health risk except at very high levels, but debate continues over the potential adverse health effects of low-level, chronic exposure to compounds such as disinfection byproducts. Recreational water contact can be associated with adverse health outcomes either from microbial infections or exposure to cyanobacterial toxins. Environmental issues such as increasing salinity and global warming are likely to affect the sustainability of our current drinking water supplies and increase the threat of waterborne disease outbreaks. New technologies, use of alternative water sources, such as rainwater tanks, water reuse and restrictions will undoubtedly be part of the solution to our diminishing water resources, but have the potential to introduce new health threats.

Groundwater conditions in Georgia, 2012–14

USGS Publications Warehouse

Peck, Michael F.; Painter, Jaime A.

2016-12-07

The U.S. Geological Survey collects groundwater data and conducts studies to monitor hydrologic conditions, better define groundwater resources, and address problems related to water supply, water use, and water quality. In Georgia, water levels were monitored continuously at 181 wells during calendar year 2012, 185 wells during calendar year 2013, and at 171 wells during calendar year 2014. Because of missing data or short periods of record (less than 3 years) for several of these wells, a total of 164 wells are discussed in this report. These wells include 17 in the surficial aquifer system, 18 in the Brunswick aquifer system and equivalent sediments, 68 in the Upper Floridan aquifer, 15 in the Lower Floridan aquifer and underlying units, 10 in the Claiborne aquifer, 1 in the Gordon aquifer, 11 in the Clayton aquifer, 16 in the Cretaceous aquifer system, 2 in Paleozoic-rock aquifers, and 6 in crystalline-rock aquifers. Data from the well network indicate that water levels generally rose during the 2012 through 2014 calendar-year period, with water levels rising in 151 wells, declining in 12, and remained about the same in 1. Water levels declined over the long-term period of record at 94 wells, increased at 60 wells, and remained relatively constant at 10 wells.In addition to continuous water-level data, periodic water-level measurements were collected and used to construct potentiometric-surface maps for the Upper Floridan aquifer in the following areas in Georgia: the Brunswick-Glynn County area during August 2012 and October 2014 and in the Albany-Dougherty County area during November 2012 and November 2014. Periodic water-level measurements were also collected and used to construct potentiometric surface maps for the Cretaceous aquifer system in the Augusta-Richmond County area during August 2012 and July 2014. In general, water levels in these areas were higher during 2014 than during 2012; however, the configuration of the potetiometric surface in each of the areas showed little change.In the Brunswick area, maps showing chloride concentration of water in the Upper Floridan aquifer (constructed using data collected from 25 wells during August 2012 and from 32 wells during October 2014) indicate that chloride concentrations remained above the U.S. Environmental Protection Agency's secondary drinking-water standard in an approximately 2-square-mile area. During calendar years 2012 through 2014, chloride concentrations generally increased in over 90 percent of the wells sampled with a maximum increase of 410 milligrams per liter in a well located in the north-central part of the Brunswick area.

Fluoride and bacterial content of bottled drinking water versus municipal tap water.

PubMed

Mythri, H; Chandu, G N; Prashant, G M; Subba Reddy, V V

2010-01-01

Water is a divine gift. People quench their thirst without questioning the source of water. But, apprehension about contaminants in municipal water supplies along with increased fear of fluorosis made bottled drinking water as one of the important tradable commodities. The objectives of the study were to determine and compare the fluoride and bacterial contents of commercially available bottled drinking water and municipal tap water in Davangere city, Karnataka. Fifty samples of 10 categories of bottled drinking water with different batch numbers were purchased and municipal water from different sources were collected. Fluoride levels were determined by an ion-selective electrode. Water was cultured quantitatively and levels of bacteria were calculated as colony-forming units (CFUs) per milliliter. Descriptive analysis of water samples for fluoride concentration was in the range of 0.07-0.33 for bottled drinking water, Bisleri showing the highest of 0.33. A comparison of the mean values of microbial count for bottled drinking water with that of municipal tap water showed no statistically significant difference, but was more than the standard levels along with the presence of fungus and maggots. The fluoride concentration was below the optimal level for both municipal tap water and bottled drinking water. CFUs were more than the recommended level in both municipal tap water and bottled drinking water.

Groundwater conditions in Georgia, 2015–16

USGS Publications Warehouse

Gordon, Debbie W.; Painter, Jaime A.

2018-02-21

The U.S. Geological Survey collects groundwater data and conducts studies to monitor hydrologic conditions, define groundwater resources, and address problems related to water supply, water use, and water quality. In Georgia, water levels were monitored continuously at 157 wells during calendar years 2015 and 2016. Because of missing data or short periods of record (less than 5 years) for several of these wells, data for 147 wells are presented in this report. These wells include 15 in the surficial aquifer system, 18 in the Brunswick aquifer system and equivalent sediments, 59 in the Upper Floridan aquifer, 13 in the Lower Floridan aquifer and underlying units, 9 in the Claiborne aquifer, 1 in the Gordon aquifer, 8 in the Clayton aquifer, 16 in the Cretaceous aquifer system, 2 in Paleozoic-rock aquifers, and 6 in crystalline-rock aquifers. Data from the well network indicate that water levels generally rose during the 10-year period from 2007 through 2016, with water levels rising in 105 wells and declining in 31 wells; insufficient data prevented determination of a 10-year trend in 11 wells. Water levels declined over the long-term period of record at 80 wells, increased at 62 wells, and remained relatively constant at 5 wells.In addition to continuous water-level data, periodic water-level data were collected and used to construct potentiometric-surface maps for the Upper Floridan aquifer in the Brunswick–Glynn County area during October 2015 and October 2016 and in the Albany–Dougherty County area during December 2015 and November and December 2016. Periodic water-level measurements were also collected and used to construct potentiometric-surface maps for the Cretaceous aquifer system in the Augusta–Richmond County area during July 2015 and June 2016. In general, water levels in the Upper Floridan aquifer were higher during 2015 than during 2016 in the Brunswick–Glynn County and Albany–Dougherty County areas due to higher precipitation during 2015. Water levels were lower, however, during 2015 than during 2016 in the Cretaceous aquifer system in the Augusta–Richmond County area.In the Brunswick area, maps showing the chloride concentration of water in the Upper Floridan aquifer constructed using data collected from 33 wells during October 2015 and from 30 wells during October 2016 indicate that chloride concentrations remained above the U.S. Environmental Protection Agency’s secondary drinking-water standard in an approximately 2-square-mile area. During calendar years 2015–16, chloride concentrations generally were similar to those measured during 2012–14; however, some wells did show an increase in chloride concentration, likely due to increases in pumping.

Drought and the water-energy nexus in Texas

NASA Astrophysics Data System (ADS)

Scanlon, Bridget R.; Duncan, Ian; Reedy, Robert C.

2013-12-01

Texas experienced the most extreme drought on record in 2011 with up to 100 days of triple digit temperatures resulting in record electricity demand and historically low reservoir levels. We quantified water and electricity demand and supply for each power plant during the drought relative to 2010 (baseline). Drought raised electricity demands/generation by 6%, increasing water demands/consumption for electricity by 9%. Reductions in monitored reservoir storage <50% of capacity in 2011 would suggest drought vulnerability, but data show that the power plants were flexible enough at the plant level to adapt by switching to less water-intensive technologies. Natural gas, now ˜50% of power generation in Texas, enhances drought resilience by increasing the flexibility of power plant generators, including gas combustion turbines to complement increasing wind generation and combined cycle generators with ˜30% of cooling water requirements of traditional steam turbine plants. These reductions in water use are projected to continue to 2030 with increased use of natural gas and renewables. Although water use for gas production is controversial, these data show that water saved by using natural gas combined cycle plants relative to coal steam turbine plants is 25-50 times greater than the amount of water used in hydraulic fracturing to extract the gas.

Effects of volume change on the unsaturated hydraulic conductivity of Sphagnum moss

NASA Astrophysics Data System (ADS)

Golubev, V.; Whittington, P.

2018-04-01

Due to the non-vascular nature of Sphagnum mosses, the capitula (growing surface) of the moss must rely solely on capillary action to receive water from beneath. Moss subsides and swells in accordance with water table levels, an effect called "mire-breathing", which has been thought to be a self-preservation mechanism, although no systematic studies have been done to demonstrate exactly how volume change affects hydrophysical properties of moss. In this study, the unsaturated hydraulic conductivity (Kunsat) and water content of two different species of Sphagnum moss were measured at different compression rates, up to the maximum of 77%. The findings show that the Kunsat increases by up to an order of magnitude (10×) with compression up to a certain bulk density of the moss, after which higher levels of compression result in lowered unsaturated hydraulic conductivity. This was coupled with an increase in soil water retention with increased compression. The increase of the Kunsat with compression suggests that the mire-breathing effect should be considered a self-preservation mechanism to provide sufficient amount of water to growing moss in times of low water availability.

Does Global Progress on Sanitation Really Lag behind Water? An Analysis of Global Progress on Community- and Household-Level Access to Safe Water and Sanitation

PubMed Central

Cumming, Oliver; Elliott, Mark; Overbo, Alycia; Bartram, Jamie

2014-01-01

Safe drinking water and sanitation are important determinants of human health and wellbeing and have recently been declared human rights by the international community. Increased access to both were included in the Millennium Development Goals under a single dedicated target for 2015. This target was reached in 2010 for water but sanitation will fall short; however, there is an important difference in the benchmarks used for assessing global access. For drinking water the benchmark is community-level access whilst for sanitation it is household-level access, so a pit latrine shared between households does not count toward the Millennium Development Goal (MDG) target. We estimated global progress for water and sanitation under two scenarios: with equivalent household- and community-level benchmarks. Our results demonstrate that the “sanitation deficit” is apparent only when household-level sanitation access is contrasted with community-level water access. When equivalent benchmarks are used for water and sanitation, the global deficit is as great for water as it is for sanitation, and sanitation progress in the MDG-period (1990–2015) outstrips that in water. As both drinking water and sanitation access yield greater benefits at the household-level than at the community-level, we conclude that any post–2015 goals should consider a household-level benchmark for both. PMID:25502659

Does global progress on sanitation really lag behind water? An analysis of global progress on community- and household-level access to safe water and sanitation.

PubMed

Cumming, Oliver; Elliott, Mark; Overbo, Alycia; Bartram, Jamie

2014-01-01

Safe drinking water and sanitation are important determinants of human health and wellbeing and have recently been declared human rights by the international community. Increased access to both were included in the Millennium Development Goals under a single dedicated target for 2015. This target was reached in 2010 for water but sanitation will fall short; however, there is an important difference in the benchmarks used for assessing global access. For drinking water the benchmark is community-level access whilst for sanitation it is household-level access, so a pit latrine shared between households does not count toward the Millennium Development Goal (MDG) target. We estimated global progress for water and sanitation under two scenarios: with equivalent household- and community-level benchmarks. Our results demonstrate that the "sanitation deficit" is apparent only when household-level sanitation access is contrasted with community-level water access. When equivalent benchmarks are used for water and sanitation, the global deficit is as great for water as it is for sanitation, and sanitation progress in the MDG-period (1990-2015) outstrips that in water. As both drinking water and sanitation access yield greater benefits at the household-level than at the community-level, we conclude that any post-2015 goals should consider a household-level benchmark for both.

A hydro-economic model for water level fluctuations: combining limnology with economics for sustainable development of hydropower.

PubMed

Hirsch, Philipp Emanuel; Schillinger, Sebastian; Weigt, Hannes; Burkhardt-Holm, Patricia

2014-01-01

Water level fluctuations in lakes lead to shoreline displacement. The seasonality of flooding or beaching of the littoral area affects nutrient cycling, redox gradients in sediments, and life cycles of aquatic organisms. Despite the ecological importance of water level fluctuations, we still lack a method that assesses water levels in the context of hydropower operations. Water levels in reservoirs are influenced by the operator of a hydropower plant, who discharges water through the turbines or stores water in the reservoir, in a fashion that maximizes profit. This rationale governs the seasonal operation scheme and hence determines the water levels within the boundaries of the reservoir's water balance. For progress towards a sustainable development of hydropower, the benefits of this form of electricity generation have to be weighed against the possible detrimental effects of the anthropogenic water level fluctuations. We developed a hydro-economic model that combines an economic optimization function with hydrological estimators of the water balance of a reservoir. Applying this model allowed us to accurately predict water level fluctuations in a reservoir. The hydro-economic model also allowed for scenario calculation of how water levels change with climate change scenarios and with a change in operating scheme of the reservoir (increase in turbine capacity). Further model development will enable the consideration of a variety of additional parameters, such as water withdrawal for irrigation, drinking water supply, or altered energy policies. This advances our ability to sustainably manage water resources that must meet both economic and environmental demands.

A Hydro-Economic Model for Water Level Fluctuations: Combining Limnology with Economics for Sustainable Development of Hydropower

PubMed Central

Hirsch, Philipp Emanuel; Schillinger, Sebastian; Weigt, Hannes; Burkhardt-Holm, Patricia

2014-01-01

Water level fluctuations in lakes lead to shoreline displacement. The seasonality of flooding or beaching of the littoral area affects nutrient cycling, redox gradients in sediments, and life cycles of aquatic organisms. Despite the ecological importance of water level fluctuations, we still lack a method that assesses water levels in the context of hydropower operations. Water levels in reservoirs are influenced by the operator of a hydropower plant, who discharges water through the turbines or stores water in the reservoir, in a fashion that maximizes profit. This rationale governs the seasonal operation scheme and hence determines the water levels within the boundaries of the reservoir's water balance. For progress towards a sustainable development of hydropower, the benefits of this form of electricity generation have to be weighed against the possible detrimental effects of the anthropogenic water level fluctuations. We developed a hydro-economic model that combines an economic optimization function with hydrological estimators of the water balance of a reservoir. Applying this model allowed us to accurately predict water level fluctuations in a reservoir. The hydro-economic model also allowed for scenario calculation of how water levels change with climate change scenarios and with a change in operating scheme of the reservoir (increase in turbine capacity). Further model development will enable the consideration of a variety of additional parameters, such as water withdrawal for irrigation, drinking water supply, or altered energy policies. This advances our ability to sustainably manage water resources that must meet both economic and environmental demands. PMID:25526619

History of ground-water pumpage and water-level decline in the Black Creek and upper Cape Fear aquifers of the central coastal plain of North Carolina

USGS Publications Warehouse

Winner, M.D.; Lyke, W.L.

1986-01-01

Historical ground-water withdrawals and a general water-level decline in the Black Creek and upper Cape Fear aquifers of the central Coastal Plain of North Carolina are documented. Total municipal and industrial pumpage from these aquifers has increased from approximately 120,000 gal/day (gpd) in 1910 to >21 million gpd in 1980. Major pumpage, > 10,000 gpd, began around 1900. Since that time, per capita water use in the central Coastal Plain area has ranged from 17 to 172 gpd/person. The higher values partially represent the increasing availability and use of modern conveniences since the World War II era. The range of per capita water use can be subdivided according to general water-use and population characteristics for both urban and rural areas. The pumpage of ground water from the Black Creek and upper Cape Fear aquifers has created water-level declines from 0.5 to 4.9 ft/year since 1900. Approximately a third of the study area has experienced a decline > 50 ft up to the period 1979-1981, with 148 ft being the maximum.

Water Levels In Major Artesian Aquifers Of The New Jersey Coastal Plain, 1988

USGS Publications Warehouse

Rosman, Robert; Lacombe, Pierre J.; Storck, Donald A.

1995-01-01

Water levels in 1,251 wells in the New Jersey Coastal Plain, Philadelphia County, Pennsylvania, and Kent and New Castle Counties, Delaware, were measured from October 1988 to February 1989 and compared with 1,071 water levels measured from September 1983 to May 1984. Water levels in 916 of the wells measured in the 1983 study were remeasured in the 1988 study. Alternate wells were selected to replace wells used in 1983 that were inaccessible at the time of the water-level measurements in 1988 or had been destroyed. New well sites were added in strategic locations to increase coverage where possible. Large cones of depression have formed or expanded in the nine major artesian aquifers that underlie the New Jersey Coastal Plain. Water levels are shown on nine potentiometric-surface maps. Hydrographs for observation wells typically show water-level declines for 1983, through 1989. In the confined Cohansey aquifer, the lowest water level, 20 feet below sea level, was measured in a well located at Cape May City Water Department, Cape May County. Water levels in the Atlantic City 800-foot sand declined as much as 21 feet at Ventnor, Atlantic County, over the 6-year period from the 1983 study to this study for 1988. Water levels in the Piney Point aquifer were as low as 56 feet below sea level at Seaside Park, Ocean County; 45 feet below sea level in southern Cumberland County; and 28 feet below sea level at Margate, Atlantic County. Water levels in the Vincentown aquifer did not change over the 6-year period. The lowest water levels in the Wenonah-Mount Laurel aquifer and the Englishtown aquifer system were 218 feet and 256 feet below sea level, respectively. Large cones of depression in the Potomac- Raritan-Magothy aquifer system are centered in the Camden County area and the Middlesex and Monmouth County area. Water levels declined as much as 46 feet in these areas over the 6-year period.

Maps showing water-level declines, land subsidence, and earth fissures in south-central Arizona

USGS Publications Warehouse

Laney, R.L.; Raymond, R.H.; Winikka, C.C.

1978-01-01

From 1915 to 1975, more than 109 million acre-feet of ground water was withdrawn from about 4,500 square miles in Pinal and Maricopa Counties in south-central Arizona. The volume of water withdrawn greatly exceeds the volume of natural recharge, and water levels have been declining since 1923. As a result of the water-level declines, the land surface has subsided, the alluvial deposits have been subjected to stress, and earth fissures have developed. Land subsidence and earth fissures have damaged public and private properties. Subsidence and fissures will continue to occur as long as ground water is being mined and water levels continue to decline. As urban development expands, land subsidence and earth fissures will have an increasing socioeconomic impact. Information on maps includes change in water levels, measurements of land subsidence, and location of earth fissures. A section showing land subsidence between Casa Grande and the Picacho Peak Interchange also is included. Scale 1:250,000. (Woodard-USGS)

Ground-Water Conditions and Studies in Georgia, 2004-2005

USGS Publications Warehouse

Leeth, David C.; Peck, Michael F.; Painter, Jaime A.

2007-01-01

The U.S. Geological Survey (USGS) collects ground-water data and conducts studies to monitor hydrologic conditions, better define ground-water resources, and address problems related to water supply, water use, and water quality. During 2004-2005, ground-water levels were monitored continuously in a network of 183 wells completed in major aquifers throughout the State. Because of missing data or the short period of record for a number of these wells (less than 3 years), a total of 171 wells from the network are discussed in this report. These wells include 19 in the surficial aquifer system, 20 in the Brunswick aquifer system and equivalent sediments, 69 in the Upper Floridan aquifer, 17 in the Lower Floridan aquifer and underlying units, 10 in the Claiborne aquifer, 1 in the Gordon aquifer, 10 in the Clayton aquifer, 12 in the Cretaceous aquifer system, 2 in Paleozoic-rock aquifers, and 11 in crystalline-rock aquifers. Data from the network indicate that generally water levels rose after the end of a drought (fall 2002), with water levels in 152 of the wells in the normal or above-normal range by 2005. An exception to this pattern of water-level recovery is in the Cretaceous aquifer system where water levels in 7 of the 12 wells monitored were below normal during 2005. In addition to continuous water-level data, periodic synoptic water-level measurements were collected and used to construct potentiometric-surface maps for the Upper Floridan aquifer in the Camden County-Charlton County area during September 2004 and May 2005, in the Brunswick area during June 2004 and June 2005, and in the City of Albany-Dougherty County area during October 2004 and during October 2005. In general, the configuration of the potentiometric surfaces showed little change during 2004-2005 in each of the areas. Ground-water quality in the Upper Floridan aquifer is monitored in the Albany, Savannah, and Brunswick areas, and in Camden County; and the Lower Floridan aquifer, monitored in the Savannah and Brunswick areas and in Camden County. In the Albany area, nitrate concentrations generally increased since the end of the drought during 2002. Concentrations increased in water collected from 13 of the 16 wells sampled during 2004-2005 and by November 2005, water from 2 wells had nitrate as N concentrations that were above the U.S. Environmental Protection Agency's (USEPA) 10-milligram-per-liter (mg/L) drinking-water standard. In the Savannah area, measurement of fluid conductivity and chloride concentration in water samples from discrete depths in three wells completed in the Upper Floridan aquifer and one well in the Lower Floridan aquifer were used to assess changes in water quality in the Savannah area. At Tybee Island, chloride concentrations in samples from the Lower Floridan aquifer increased during 2004-2005 and were above the 250-mg/L USEPA drinking-water standard. At Skidaway Island, water in the Upper Floridan aquifer is fresh, and chloride concentrations did not appreciably change during 2004-2005. However, chloride concentrations in samples collected from the Lower Floridan aquifer during 2004-2005 showed disparate changes; whereby, chloride concentration increased in the deepest sampled interval (1,070 feet) and decreased in a shallower sampled interval (900 feet). At Fort Pulaski, water samples collected from the Upper Floridan aquifer are fresh and did not appreciably change during 2004-2005. In the Brunswick area, maps showing the chloride concentration of water in the Upper Floridan aquifer were constructed using data collected from 41 wells during June 2004 and from 39 wells during June 2005. Analyses indicate that concentrations remained above the USEPA drinking-water standard in an approximate 2-square-mile area. During 2004-2005, chloride concentrations increased in samples from 18 wells and decreased in samples from 11 wells. In the Camden County area, chloride concentrations during 2004-2005 were analyzed in water

Water underground

NASA Astrophysics Data System (ADS)

de Graaf, Inge

2015-04-01

The world's largest assessable source of freshwater is hidden underground, but we do not know what is happening to it yet. In many places of the world groundwater is abstracted at unsustainable rates: more water is used than being recharged, leading to decreasing river discharges and declining groundwater levels. It is predicted that for many regions of the world unsustainable water use will increase, due to increasing human water use under changing climate. It would not be long before shortage causes widespread droughts and the first water war begins. Improving our knowledge about our hidden water is the first step to stop this. The world largest aquifers are mapped, but these maps do not mention how much water they contain or how fast water levels decline. If we can add a third dimension to the aquifer maps, so a thickness, and add geohydrological information we can estimate how much water is stored. Also data on groundwater age and how fast it is refilled is needed to predict the impact of human water use and climate change on the groundwater resource.

Geohydrology of the North Park area, Jackson County, Colorado; with a section on water law

USGS Publications Warehouse

Robson, Stanley G.; Graham, Glenn

1996-01-01

Increasing population in rural and suburban areas of Colorado is causing greater reliance on ground water as a source of domestic supply. In the primarily rural area of Jackson County, for example, the number of registered water wells increased from about 100 in 1972 to about 500 in 1995. Most of the new wells were drilled after 1988 and supply water to ranches and summer homes. In Jackson County, ground water is pumped from a series of shallow alluvial aquifers along principal stream valleys and from deeper, more extensive, bedrock aquifers. In much of the area, the alluvial aquifers are thin and can be dewatered by moderate water- level declines. Knowledge of the nature and extent of the alluvial and bedrock aquifers, the sources of recharge and discharge, and the effects of ground- water withdrawal on water levels in the aquifers is vital if management of the area's water resources is to ensure continued availability of a dependable water supply.

Simulation of ground-water flow and evaluation of water-management alternatives in the upper Charles River basin, eastern Massachusetts

USGS Publications Warehouse

DeSimone, Leslie A.; Walter, Donald A.; Eggleston, John R.; Nimiroski, Mark T.

2002-01-01

Ground water is the primary source of drinking water for towns in the upper Charles River Basin, an area of 105 square miles in eastern Massachusetts that is undergoing rapid growth. The stratified-glacial aquifers in the basin are high yield, but also are thin, discontinuous, and in close hydraulic connection with streams, ponds, and wetlands. Water withdrawals averaged 10.1 million gallons per day in 1989?98 and are likely to increase in response to rapid growth. These withdrawals deplete streamflow and lower pond levels. A study was conducted to develop tools for evaluating water-management alternatives at the regional scale in the basin. Geologic and hydrologic data were compiled and collected to characterize the ground- and surface-water systems. Numerical flow modeling techniques were applied to evaluate the effects of increased withdrawals and altered recharge on ground-water levels, pond levels, and stream base flow. Simulation-optimization methods also were applied to test their efficacy for management of multiple water-supply and water-resource needs. Steady-state and transient ground-water-flow models were developed using the numerical modeling code MODFLOW-2000. The models were calibrated to 1989?98 average annual conditions of water withdrawals, water levels, and stream base flow. Model recharge rates were varied spatially, by land use, surficial geology, and septic-tank return flow. Recharge was changed during model calibration by means of parameter-estimation techniques to better match the estimated average annual base flow; area-weighted rates averaged 22.5 inches per year for the basin. Water withdrawals accounted for about 7 percent of total simulated flows through the stream-aquifer system and were about equal in magnitude to model-calculated rates of ground-water evapotranspiration from wetlands and ponds in aquifer areas. Water withdrawals as percentages of total flow varied spatially and temporally within an average year; maximum values were 12 to 13 percent of total annual flow in some subbasins and of total monthly flow throughout the basin in summer and early fall. Water-management alternatives were evaluated by simulating hypothetical scenarios of increased withdrawals and altered recharge for average 1989?98 conditions with the flow models. Increased withdrawals to maximum State-permitted levels would result in withdrawals of about 15 million gallons per day, or about 50 percent more than current withdrawals. Model-calculated effects of these increased withdrawals included reductions in stream base flow that were greatest (as a percentage of total flow) in late summer and early fall. These reductions ranged from less than 5 percent to more than 60 percent of model-calculated 1989?98 base flow along reaches of the Charles River and major tributaries during low-flow periods. Reductions in base flow generally were comparable to upstream increases in withdrawals, but were slightly less than upstream withdrawals in areas where septic-system return flow was simulated. Increased withdrawals also increased the proportion of wastewater in the Charles River downstream of treatment facilities. The wastewater component increased downstream from a treatment facility in Milford from 80 percent of September base flow under 1989?98 conditions to 90 percent of base flow, and from 18 to 27 percent of September base flow downstream of a treatment facility in Medway. In another set of hypothetical scenarios, additional recharge equal to the transfer of water out of a typical subbasin by sewers was found to increase model-calculated base flows by about 12 percent of model-calculated base flows. Addition of recharge equal to that available from artificial recharge of residential rooftop runoff had smaller effects, augmenting simulated September base flow by about 3 percent. Simulation-optimization methods were applied to an area near Populatic Pond and the confluence of the Mill and Charles Rivers in Franklin,

Numerical Simulation of the Effect about Groundwater Level Fluctuation on the Concentration of BTEX Dissolved into Source Zone

NASA Astrophysics Data System (ADS)

Sun, Liqun; Chen, Yudao; Jiang, Lingzhi; Cheng, Yaping

2018-01-01

The water level fluctuation of groundwater will affect the BTEX dissolution in the fuel leakage source zone. In order to study the effect, a leakage test of gasoline was performed in the sand-tank model in the laboratory, and the concentrations of BTEX along with water level were monitored over a long period. Combined with VISUAL MODFLOW software, RT3D module was used to simulate the concentrations of BTEX, and mass flux method was used to evaluate the effects of water level fluctuation on the BTEX dissolution. The results indicate that water level fluctuation can significantly increase the concentration of BTEX dissolved in the leakage source zone. The dissolved amount of BTEX can reach up to 2.4 times under the water level fluctuation condition. The method of numerical simulation combined with mass flux calculation can be used to evaluate the effect of water level fluctuation on BTEX dissolution.

Modification of land-atmosphere interactions by CO2 effects: Implications for summer dryness and heat wave amplitude

NASA Astrophysics Data System (ADS)

Lemordant, Léo.; Gentine, Pierre; Stéfanon, Marc; Drobinski, Philippe; Fatichi, Simone

2016-10-01

Plant stomata couple the energy, water, and carbon cycles. We use the framework of Regional Climate Modeling to simulate the 2003 European heat wave and assess how higher levels of surface CO2 may affect such an extreme event through land-atmosphere interactions. Increased CO2 modifies the seasonality of the water cycle through stomatal regulation and increased leaf area. As a result, the water saved during the growing season through higher water use efficiency mitigates summer dryness and the heat wave impact. Land-atmosphere interactions and CO2 fertilization together synergistically contribute to increased summer transpiration. This, in turn, alters the surface energy budget and decreases sensible heat flux, mitigating air temperature rise. Accurate representation of the response to higher CO2 levels and of the coupling between the carbon and water cycles is therefore critical to forecasting seasonal climate, water cycle dynamics, and to enhance the accuracy of extreme event prediction under future climate.

Increasing extreme water level flood risk as a result of future sea-level rise: A case study on a coastal city in China

NASA Astrophysics Data System (ADS)

Feng, A.; Wu, S.

2016-12-01

Extreme water levels, caused by the joint occurrence of storm surges and high tides, always lead to super floods along coastlines. In the context of climate change, this study explored the impact of future sea-level rise on the flood risk of extreme water levels. Using Rongcheng City in Shandong Province, China as a case study, flooded area, expected direct damage losses, and affected population and GDP were assessed for 2050 and 2100 under three greenhouse gas concentration Representative Concentration Pathways (RCP) scenarios, 2.6, 4.5, and 8.5. Results indicate that, as a result of sea-level rise induced by climate change, the flooded areas of Rongcheng City would increase by 3.23% to 10.64% in 2050 and by as much as 4.98% to 19.87% in 2100, compared with current recurrence periods. Residential land and farmland are at greatest risk of flooding in terms of exposure and losses than other land-use types, and under a high degree RCP 8.5 scenario, expected damage losses would be between 59.84 billion and 86.45 billion in 2050. Results show that the increase in total direct damage losses would reach an average of 60% in 2100 as a result of a 0.82 m sea-level rise. Similarly, affected population and GDP would increase by between 4.95% and 13.87% and between 3.66% and 10.95% in 2050, and by as much as 7.69% to 29.01% and 5.30% to 20.50% in 2100. This study shows that sea-level rise significantly shortens recurrence periods of extreme water levels, makes extreme flood events more frequent, and exacerbates the risk of future flooding. Our results suggest that, if there is no adaptation, sea-level rise will greatly increase the risk of flooding and severely impact human habitability along coastlines.

Predcition of Long term Water table Trends in Response to Groundwater Irrigation and Climate Change in an Indian Context

NASA Astrophysics Data System (ADS)

Thekkemeppilly Sivakumar, I.; Steenhuis, T. S.; Walter, M. F.; Ghosh, S.; Salvi, K. A.

2015-12-01

Intensified groundwater irrigation is a major factor that contributes to water table decline. This phenomenon has been documented in many parts of the world. This study investigates trends in water table in response to agriculture intensification to meet increasing food demand, water management practices and climate change. A shallow-aquifer model based on the extended Thornthwaite-Mather procedure is used to predict groundwater levels in response to precipitation, evapotranspiration, and groundwater pumping for irrigation. Krishna district in the state of Andhra Pradesh in southern India which has a sub-humid, monsoon climate and Calicut district of Kerala state with a wet tropical monsoon climate have been chosen as sites for this study. The effect of increasing food demand by a growing population is investigated by increasing the number of crops per year from one to three. We consider three climate scenarios and two water management practices in this study. The three climate scenarios are the ones those envisaged by the Intergovernmental Panel for Climate Change (IPCC). The two water management practices considered are the traditional flooded agriculture and the system of rice intensification method which does not use total flooding. The results show that single crop agriculture in Krishna district is sustainable for all climate scenarios and water management practices with a maximum depth to water table around 6 - 7 m at the end of dry season and the water table recovers to the surface most of the time. Increasing crop production with two or three crops per year with groundwater irrigation is unsustainable with the water table levels dropping potentially to 200 - 1000 m at the end of 21st century. We found that climate change and better irrigation water management practices affected ground water levels only minimally compared to the growing more than one crop per year. Our study leads to the conclusion that ground water irrigated rice can only be sustainable when crop evaporation is less then precipitation and in order to meet increasing food demands the rice yield per unit water should be improved.

Hydrology of the Reelfoot Lake basin, Obion and Lake counties, northwestern Tennessee

USGS Publications Warehouse

Robbins, C.H.

1985-01-01

Nine maps describe the following water resources aspects of the Reelfoot Lake watershed: Map 1-Surface water gaging stations, lake level, and locations of observation wells, rainfall stations and National Weather Service rainfall stations; Maps 2 and 3-water level contours, river stage, groundwater movement; Maps 4 and 5-grid blocks simulating constant head on the Mississippi River, Reelfoot Lake, Running Reelfoot Bayou, Reelfoot Creek, and Running Slough; Maps 6 and 7-difference between model calculated and observed water levels; and Maps 8 and 9-line of equal groundwater level increase and approximate lake area at pool elevation. (Lantz-PTT)

Source of salts in the Waianae part of the Pearl Harbor aquifer near Barbers Point water tunnel, Oahu, Hawaii

USGS Publications Warehouse

Eyre, P.R.

1987-01-01

The salinity of the water supply of Barbers Point Naval Air Station has increased markedly since 1983. The Naval Air Station obtains its water, about 3 million gal/day, from Barbers Point shaft, a water shaft that taps the Waianae part of the Pearl Harbor aquifer underlying the dry, southeastern flank of the Waianae mountains on the island on Oahu, Hawaii. From 1983 to 1985 the chloride concentration of the water, increased from 220 to 250 mg/L and has remained near that level through 1986. The EPA has established 250 mg/L as the maximum recommended chloride concentration in drinking water because above that level many people can taste the salt. The high chloride concentration in shallow groundwater at all wells in the area indicates that most of the salts in the freshwater lens are contributed by rainfall, sea spray, and irrigation return water. At Barbers Point shaft, pumping may draw a small amount of saltwater from the transition zone and increase the chloride concentration in the pumped water by about 20 mg/L. Salinity of the lens decreases progressively inland in response to recharge from relatively fresher water and in response to an increasing lens thickness with increasing distance from the shoreline. The increase, in 1983, in the chloride concentration of water at the shaft was most probably the result of saltier recharge water reaching the water table, and not the result of increased mixing of underlying saltwater with the freshwater. The chloride concentration of the recharge water has probably increased because, in 1980, the drip method of irrigation began to replace the furrow method on sugarcane fields near the shaft. A mixing-cell model was used to estimate the effect of drip irrigation on the chloride concentration of the groundwater in the vicinity of Barbers Point shaft. The model predicted an increase in chloride concentration of about 50 mg/L. The observed increase was about 30 mg/L and the chloride concentration is presently stable at 245 to 250 mg/L; hence, the chloride concentration is not expected to increase significantly more. (Lantz-PTT)

The influence of water depth on kinematic and spatiotemporal gait parameters during aquatic treadmill walking.

PubMed

Jung, Taeyou; Kim, Yumi; Lim, Hyosok; Vrongistinos, Konstantinos

2018-01-16

The purpose of this study was to investigate kinematic and spatiotemporal variables of aquatic treadmill walking at three different water depths. A total of 15 healthy individuals completed three two-minute walking trials at three different water depths. The aquatic treadmill walking was conducted at waist-depth, chest-depth and neck-depth, while a customised 3-D underwater motion analysis system captured their walking. Each participant's self-selected walking speed at the waist level was used as a reference speed, which was applied to the remaining two test conditions. A repeated measures ANOVA showed statistically significant differences among the three walking conditions in stride length, cadence, peak hip extension, hip range of motion (ROM), peak ankle plantar flexion and ankle ROM (All p values < 0.05). The participants walked with increased stride length and decreased cadence during neck level as compared to waist and chest level. They also showed increased ankle ROM and decreased hip ROM as the water depth rose from waist and chest to the neck level. However, our study found no significant difference between waist and chest level water in all variables. Hydrodynamics, such as buoyancy and drag force, in response to changes in water depths, can affect gait patterns during aquatic treadmill walking.

Hydrologic Record Extension of Water-Level Data in the Everglades Depth Estimation Network (EDEN) Using Artificial Neural Network Models, 2000-2006

USGS Publications Warehouse

Conrads, Paul; Roehl, Edwin A.

2007-01-01

The Everglades Depth Estimation Network (EDEN) is an integrated network of real-time water-level gaging stations, ground-elevation models, and water-surface models designed to provide scientists, engineers, and water-resource managers with current (2000-present) water-depth information for the entire freshwater portion of the greater Everglades. The U.S. Geological Survey Greater Everglades Priority Ecosystem Science provides support for EDEN and the goal of providing quality assured monitoring data for the U.S. Army Corps of Engineers Comprehensive Everglades Restoration Plan. To increase the accuracy of the water-surface models, 25 real-time water-level gaging stations were added to the network of 253 established water-level gaging stations. To incorporate the data from the newly added stations to the 7-year EDEN database in the greater Everglades, the short-term water-level records (generally less than 1 year) needed to be simulated back in time (hindcasted) to be concurrent with data from the established gaging stations in the database. A three-step modeling approach using artificial neural network models was used to estimate the water levels at the new stations. The artificial neural network models used static variables that represent the gaging station location and percent vegetation in addition to dynamic variables that represent water-level data from the established EDEN gaging stations. The final step of the modeling approach was to simulate the computed error of the initial estimate to increase the accuracy of the final water-level estimate. The three-step modeling approach for estimating water levels at the new EDEN gaging stations produced satisfactory results. The coefficients of determination (R2) for 21 of the 25 estimates were greater than 0.95, and all of the estimates (25 of 25) were greater than 0.82. The model estimates showed good agreement with the measured data. For some new EDEN stations with limited measured data, the record extension (hindcasts) included periods beyond the range of the data used to train the artificial neural network models. The comparison of the hindcasts with long-term water-level data proximal to the new EDEN gaging stations indicated that the water-level estimates were reasonable. The percent model error (root mean square error divided by the range of the measured data) was less than 6 percent, and for the majority of stations (20 of 25), the percent model error was less than 1 percent.

Analysis of the return period and correlation between the reservoir-induced seismic frequency and the water level based on a copula: A case study of the Three Gorges reservoir in China

NASA Astrophysics Data System (ADS)

Liu, Xiaofei; Zhang, Qiuwen

2016-11-01

Studies have considered the many factors involved in the mechanism of reservoir seismicity. Focusing on the correlation between reservoir-induced seismicity and the water level, this study proposes to utilize copula theory to build a correlation model to analyze their relationships and perform the risk analysis. The sequences of reservoir induced seismicity events from 2003 to 2011 in the Three Gorges reservoir in China are used as a case study to test this new methodology. Next, we construct four correlation models based on the Gumbel, Clayton, Frank copula and M-copula functions and employ four methods to test the goodness of fit: Q-Q plots, the Kolmogorov-Smirnov (K-S) test, the minimum distance (MD) test and the Akaike Information Criterion (AIC) test. Through a comparison of the four models, the M-copula model fits the sample better than the other three models. Based on the M-copula model, we find that, for the case of a sudden drawdown of the water level, the possibility of seismic frequency decreasing obviously increases, whereas for the case of a sudden rising of the water level, the possibility of seismic frequency increasing obviously increases, with the former being greater than the latter. The seismic frequency is mainly distributed in the low-frequency region (Y ⩽ 20) for the low water level and in the middle-frequency region (20 < Y ≤ 80) for both the medium and high water levels; the seismic frequency in the high-frequency region (Y > 80) is the least likely. For the conditional return period, it can be seen that the period of the high-frequency seismicity is much longer than those of the normal and medium frequency seismicity, and the high water level shortens the periods.

Drinking Water Action Plan

EPA Pesticide Factsheets

EPA's Drinking Water Action Plan serves as a national call to action, urging all levels of government, utilities, community organizations, and other stakeholders to work together to increase the safety and reliability of drinking water.

Statistical Method for Identification of Potential Groundwater Recharge Zone

NASA Astrophysics Data System (ADS)

Banerjee, Pallavi; Singh, V. S.

2010-05-01

The effective development of groundwater resource is essential for a country like India. Artificial recharge is the planned, human activity of augmenting the amount of groundwater available through works designed to increase the natural replenishment or percolation of surface waters into the groundwater aquifers, resulting in a corresponding increase in the amount of groundwater available for abstraction. India receives good amount of average annual rainfall about 114 cm but most of it's part waste through runoff. The imbalance between rainfall and recharge has caused serious shortage of water for drinking, agriculture and industrial purposes. The over exploitation of groundwater due to increasing population is an additional cause of water crisis that resulting in reduction in per capita availability of water in the country. Thus the planning for effective development of groundwater is essential through artificial recharge. Objective of the paper is to identification of artificial recharge zones by arresting runoff through suitable sites to restore groundwater conditions using statistical technique. The water table variation follows a pattern similar to rainfall variation with time delay. The rainfall and its relationship with recharge is a very important process in a shallow aquifer system. Understanding of this process is of critical importance to management of groundwater resource in any terrain. Groundwater system in a top weathered regolith in a balastic terrain forms shallow aquifer is often classified into shallow water table category. In the present study an effort has been made to understand the suitable recharge zone with relation to rainfall and water level by using statistical analysis. Daily time series data of rainfall and borehole water level data are cross correlated to investigate variations in groundwater level response time during the months of monsoon. This measurement facilitate to demarcate favorable areas for Artificial Recharge. KEYWORDS: Water level; Rainfall; Recharge; Statistical analysis; Cross correlation.

Phosphorus and greenhouse gas dynamics in a drained calcareous wetland soil in Minnesota.

PubMed

Berryman, Erin M; Venterea, Rodney T; Baker, John M; Bloom, Paul R; Elf, Brandy

2009-01-01

Restoration of wetland hydrology can produce ecological benefits but may have unintended consequences. We examined effects of altered water level on release of dissolved reactive phosphorus (DRP) and greenhouse gases (GHG) in soil cores from a marsh being evaluated for restoration. We also measured field concentrations of DRP and other constituents in wetland porewater. Intact cores from a sampling location with higher Fe and lower calcium carbonate (CaCO(3)) contents released more DRP than another location, and displayed higher DRP under completely saturated compared to partly drained conditions. Porewater samples collected from the high-Fe location also contained higher DRP levels. Chemical data suggest that redox-driven reactions largely controlled DRP levels at the high-Fe site, while CaCO(3) adsorption was more important at the low-Fe site. Over the long term, water table elevation may attenuate P draining from the wetland due to decreased mineralization. However, such measures may increase P release in the short term. Raising the water level in soil cores resulted in decreased nitrous oxide (N(2)O) emissions, increased methane (CH(4)) emissions, and an overall increase in total global warming potential (GWP). The proportion of total GWP contributed by N(2)O decreased from 14% to < or = 1% as water level was raised, while the proportion contributed by CH(4) increased from 10 to 20% to 60 to 80%. Restoration of hydrology in the Rice Lake wetland has the potential to affect both local water quality and global air quality. These combined effects complicate the cost-to-benefit analysis of such wetland restoration efforts.

Identification of Individual Efficiency for Barometric Pressure and Ocean Tide Load Simultaneously Acted on Deep Aquifers Adjacent to the West Pacific Ocean

NASA Astrophysics Data System (ADS)

Shih, David Ching-Fang

2018-06-01

Groundwater fluctuation usually reflects the property of aquifer in nature. Actually, water level change can be caused not only by barometric pressure changes resulted from atmospheric motion, but also by the tidal effect from nearby marine system or water body. In confined aquifer, an increase in barometric pressure usually will cause a decrease in water level in well to an amount described by the barometric efficiency. The barometric efficiency can be also used as a correction factor to remove barometric effects on water levels in wells during an aquifer test. With the rise of the tidal sea on the coastal aquifer, it indicates that there will be compensating increases of water pressure and stress in the skeleton of aquifer. External forcing on groundwater level in the coastal aquifer, such as barometric effect and tidal sea, usually affect the water level to fluctuate with different phases to some extent. An adaptive adjustment to remove the combination of barometric and oceanic tidal efficiency is presented in this study. This research suggests that the presented formula can simultaneously identify the individual efficiency for barometric effect and load of tidal sea considering their combined observation of groundwater level in aquifer system. An innovative application has been demonstrated for the deep aquifers adjacent to the West Pacific Ocean.

Disaggregating residential water demand for improved forecasts and decision making

NASA Astrophysics Data System (ADS)

Woodard, G.; Brookshire, D.; Chermak, J.; Krause, K.; Roach, J.; Stewart, S.; Tidwell, V.

2003-04-01

Residential water demand is the product of population and per capita demand. Estimates of per capita demand often are based on econometric models of demand, usually based on time series data of demand aggregated at the water provider level. Various studies have examined the impact of such factors as water pricing, weather, and income, with many other factors and details of water demand remaining unclear. Impacts of water conservation programs often are estimated using simplistic engineering calculations. Partly as a result of this, policy discussions regarding water demand management often focus on water pricing, water conservation, and growth control. Projecting water demand is often a straight-forward, if fairly uncertain process of forecasting population and per capita demand rates. SAHRA researchers are developing improved forecasts of residential water demand by disaggregating demand to the level of individuals, households, and specific water uses. Research results based on high-resolution water meter loggers, household-level surveys, economic experiments and recent census data suggest that changes in wealth, household composition, and individual behavior may affect demand more than changes in population or the stock of landscape plants, water-using appliances and fixtures, generally considered the primary determinants of demand. Aging populations and lower fertility rates are dramatically reducing household size, thereby increasing the number of households and residences for a given population. Recent prosperity and low interest rates have raised home ownership rates to unprecented levels. These two trends are leading to increased per capita outdoor water demand. Conservation programs have succeeded in certain areas, such as promoting drought-tolerant native landscaping, but have failed in other areas, such as increasing irrigation efficiency or curbing swimming pool water usage. Individual behavior often is more important than the household's stock of water-using fixtures, and ranges from hedonism (installing pools and whirlpool tubs) to satisficing (adjusting irrigation timers only twice per year) to acting on deeply-held conservation ethics in ways that not only fail any benefit-cost test, but are discouraged, or even illegal (reuse of gray water and black water). Research findings are being captured in dynamic simulation models that integrate social and natural science to create tools to assist water resource managers in providing sustainable water supplies and improving residential water demand forecasts. These models feature simple, graphical user interfaces and output screens that provide decision makers with visual, easy-to-understand information at the basin level. The models reveal connections between various supply and demand components, and highlight direct impacts and feedback mechanisms associated with various policy options.

Fine sediment sources in coastal watersheds with uplifted marine terraces in northwest Humboldt County, California

Treesearch

Stephen Sungnome Madrone; Andrew P. Stubblefield

2012-01-01

Erosion in the Mill and Luffenholtz Creek watersheds in Humboldt County, California, with their extensive clay soils, can lead to high turbidity levels in receiving bodies of water, increasing the costs of treating water for domestic water supplies. Detailed road and erosion surveys and monitoring of suspended sediment, discharge, and turbidity levels in Mill Creek (3....

Potentiometric Surface of the Aquia Aquifer in Southern Maryland, September 2009

USGS Publications Warehouse

Curtin, Stephen E.; Andreasen, David C.; Staley, Andrew W.

2010-01-01

This report presents a map showing the potentiometric surface of the Aquia aquifer in the Aquia Formation of Paleocene age in Southern Maryland during September 2009. The map is based on water-level measurements in 82 wells. The highest measured water level was 48 feet above sea level near the northern boundary and in the outcrop area of the aquifer in the central part of Anne Arundel County. Water levels also were above sea level in Kent County and northern Queen Anne's County. Water levels were below sea level south and east of these areas and in the remainder of the study area. The hydraulic gradient increased southeastward toward a cone of depression around well fields at Lexington Park and Solomons Island. The lowest measured water level was 145 feet below sea level at the center of a cone of depression at Lexington Park. The map also shows well yield in gallons per day for 2008 at wells or well fields.

Responses of Water and Salt Parameters to Groundwater Levels for Soil Columns Planted with Tamarix chinensis

PubMed Central

Xia, Jiangbao; Zhao, Ximei; Chen, Yinping; Fang, Ying; Zhao, Ziguo

2016-01-01

Groundwater is the main water resource for plant growth and development in the saline soil of the Yellow River Delta in China. To investigate the variabilities and distributions of soil water and salt contents at various groundwater level (GL), soil columns with planting Tamarix chinensis Lour were established at six different GL. The results demonstrated the following: With increasing GL, the relative soil water content (RWC) declined significantly, whereas the salt content (SC) and absolute soil solution concentration (CS) decreased after the initial increase in the different soil profiles. A GL of 1.2 m was the turning point for variations in the soil water and salt contents, and it represented the highest GL that could maintain the soil surface moist within the soil columns. Both the SC and CS reached the maximum levels in these different soil profiles at a GL of 1.2 m. With the raise of soil depth, the RWC increased significantly, whereas the SC increased after an initial decrease. The mean SC values reached 0.96% in the top soil layer; however, the rates at which the CS and RWC decreased with the GL were significantly reduced. The RWC and SC presented the greatest variations at the medium (0.9–1.2 m) and shallow water levels (0.6 m) respectively, whereas the CS presented the greatest variation at the deep water level (1.5–1.8 m).The RWC, SC and CS in the soil columns were all closely related to the GL. However, the correlations among the parameters varied greatly within different soil profiles, and the most accurate predictions of the GL were derived from the RWC in the shallow soil layer or the SC in the top soil layer. A GL at 1.5–1.8 m was moderate for planting T. chinensis seedlings under saline groundwater conditions. PMID:26730602

[Effects of brackish water irrigation on soil enzyme activity, soil CO2 flux and organic matter decomposition].

PubMed

Zhang, Qian-qian; Wang, Fei; Liu, Tao; Chu, Gui-xin

2015-09-01

Brackish water irrigation utilization is an important way to alleviate water resource shortage in arid region. A field-plot experiment was set up to study the impact of the salinity level (0.31, 3.0 or 5.0 g · L(-1) NaCl) of irrigated water on activities of soil catalase, invertase, β-glucosidase, cellulase and polyphenoloxidase in drip irrigation condition, and the responses of soil CO2 flux and organic matter decomposition were also determined by soil carbon dioxide flux instrument (LI-8100) and nylon net bag method. The results showed that in contrast with fresh water irrigation treatment (CK), the activities of invertase, β-glucosidase and cellulase in the brackish water (3.0 g · L(-1)) irrigation treatment declined by 31.7%-32.4%, 29.7%-31.6%, 20.8%-24.3%, respectively, while soil polyphenoloxidase activity was obviously enhanced with increasing the salinity level of irrigated water. Compared to CK, polyphenoloxidase activity increased by 2.4% and 20.5%, respectively, in the brackish water and saline water irrigation treatments. Both soil microbial biomass carbon and microbial quotient decreased with increasing the salinity level, whereas, microbial metabolic quotient showed an increasing tendency with increasing the salinity level. Soil CO2 fluxes in the different treatments were in the order of CK (0.31 g · L(-1)) > brackish water irrigation (3.0 g · L(-1)) ≥ saline water irrigation (5.0 g · L(-1)). Moreover, CO2 flux from plastic film mulched soil was always much higher than that from no plastic film mulched soil, regardless the salinity of irrigated water. Compared with CK, soil CO2 fluxes in the saline water and brackish water treatments decreased by 29.8% and 28.2% respectively in the boll opening period. The decomposition of either cotton straw or alfalfa straw in the different treatments was in the sequence of CK (0.31 g · L(-1)) > brackish water irrigation (3.0 g · L(-1)) > saline water treatment (5.0 g · L(-1)). The organic matter decomposition rate in the plastic film mulched soil was significantly higher than that in the no plastic film mulched soil. 125 days after incubation, the recovery rates of cotton straw and alfalfa straw were 39.7% and 46.5% with saline water irrigation, 36.3% and 36.5% with brackish water irrigation, and 30.5% and 35.4% with CK, respectively. In conclusion, brackish water drip irrigation had a significant adverse effect on soil enzyme activities, which decreased soil microbial biomass, soil CO2 flux and soil organic matter decomposition, and subsequently deteriorated the soil biological characteristics in oasis farmland.

Towards a Global Water Scarcity Risk Assessment Framework: Incorporation of Probability Distributions and Hydro-Climatic Variability

NASA Technical Reports Server (NTRS)

Veldkamp, T. I. E.; Wada, Y.; Aerts, J. C. J. H.; Ward, P. J.

2016-01-01

Changing hydro-climatic and socioeconomic conditions increasingly put pressure on fresh water resources and are expected to aggravate water scarcity conditions towards the future. Despite numerous calls for risk-based water scarcity assessments, a global-scale framework that includes UNISDR's definition of risk does not yet exist. This study provides a first step towards such a risk based assessment, applying a Gamma distribution to estimate water scarcity conditions at the global scale under historic and future conditions, using multiple climate change and population growth scenarios. Our study highlights that water scarcity risk, expressed in terms of expected annual exposed population, increases given all future scenarios, up to greater than 56.2% of the global population in 2080. Looking at the drivers of risk, we find that population growth outweigh the impacts of climate change at global and regional scales. Using a risk-based method to assess water scarcity, we show the results to be less sensitive than traditional water scarcity assessments to the use of fixed threshold to represent different levels of water scarcity. This becomes especially important when moving from global to local scales, whereby deviations increase up to 50% of estimated risk levels.

Evaluation of long-term trends in hydrologic and water-quality conditions, and estimation of water budgets through 2013, Chester County, Pennsylvania

USGS Publications Warehouse

Sloto, Ronald A.; Reif, Andrew G.

2017-06-02

An evaluation of trends in hydrologic and water quality conditions and estimation of water budgets through 2013 was done by the U.S. Geological Survey in cooperation with the Chester County Water Resources Authority. Long-term hydrologic, meteorologic, and biologic data collected in Chester County, Pennsylvania, which included streamflow, groundwater levels, surface-water quality, biotic integrity, precipitation, and air temperature were analyzed to determine possible trends or changes in hydrologic conditions. Statistically significant trends were determined by applying the Kendall rank correlation test; the magnitudes of the trends were determined using the Sen slope estimator. Water budgets for eight selected watersheds were updated and a new water budget was developed for the Marsh Creek watershed. An average water budget for Chester County was developed using the eight selected watersheds and the new Marsh Creek water budget.Annual and monthly mean streamflow, base flow, and runoff were analyzed for trends at 10 streamgages. The periods of record at the 10 streamgages ranged from 1961‒2013 to 1988‒2013. The only statistically significant trend for annual mean streamflow was for West Branch Brandywine Creek near Honey Brook, Pa. (01480300) where annual mean streamflow increased 1.6 cubic feet per second (ft3/s) per decade. The greatest increase in monthly mean streamflow was for Brandywine Creek at Chadds Ford, Pa. (01481000) for December; the increase was 47 ft3/s per decade. No statistically significant trends in annual mean base flow or runoff were determined for the 10 streamgages. The greatest increase in monthly mean base flow was for Brandywine Creek at Chadds Ford, Pa. (01481000) for December; the increase was 26 ft3/s per decade.The magnitude of peaks greater than a base streamflow was analyzed for trends for 12 streamgages. The period of record at the 12 stream gages ranged from 1912‒2012 to 2004–11. Fifty percent of the streamgages showed a small statistically significant increase in peaks greater than the base streamflow. The greatest increase was for Brandywine Creek at Chadds Ford, Pa. (01481000) during 1962‒2012; the increase was 1.8 ft3/s per decade. There were no statistically significant trends in the number of floods equal to or greater than the 2-year recurrence interval flood flow.Twenty‒one monitoring wells were evaluated for statistically significant trends in annual mean water level, minimum annual water level, maximum annual water level, and annual range in water-level fluctuations. For four wells, a small statistically significant increase in annual mean water level was determined that ranged from 0.16 to 0.7 feet per decade. There was poor or no correlation between annual mean groundwater levels and annual mean streamflow and base flow. No correlation was determined between annual mean groundwater level and annual precipitation. Despite rapid population growth and land-use change since 1950, there appears to have been little or no detrimental effects on groundwater levels in 21 monitoring wells.Long-term precipitation and temperature data were available from the West Chester (1893‒2013) and Phoenixville, Pa. (1915‒2013) National Oceanic and Atmospheric Administration (NOAA) weather stations. No statistically significant trends in annual mean precipitation or annual mean temperature were determined for either station. Both weather stations had a significant decrease in the number of days per year with precipitation greater than or equal to 0.1 inch. Annual mean minimum and maximum temperatures from the NOAA Southeastern Piedmont Climate Division increased 0.2 degrees Fahrenheit (F) per decade between 1896 and 2014. The number of days with a maximum temperature equal to or greater than 90 degrees F increased at West Chester and decreased at Phoenixville. No statistically significant trend was determined for annual snowfall amounts.Data from 1974 to 2013 for three stream water-quality monitors in the Brandywine Creek watershed were evaluated. The monitors are on the West Branch Brandywine Creek at Modena, Pa. (01480617), East Branch Brandywine Creek below Downingtown, Pa. (01480870), and Brandywine Creek at Chadds Ford, Pa. (01481000). Statistically significant upward trends were determined for annual mean specific conductance at all three stations, indicating the total dissolved solids load has been increasing. If the current trend continues, the annual mean specific conductance could almost double from 1974 to 2050. The increase in specific conductance likely is due to increases in chloride concentrations, which have been increasing steadily over time at all three stations. No correlation was found between monthly mean specific conductance and monthly mean streamflow or base flow. Statistically significant upward trends in pH were determined for all three stations. Statistically significant upward trends in stream temperature were determined for East Branch Brandywine Creek below Downingtown, Pa. (01480870) and Brandywine Creek at Chadds Ford, Pa. (01481000). The stream water-quality data indicate substantial increases in the minimum daily dissolved oxygen concentrations in the Brandywine Creek over time.The Chester County Index of Biotic Integrity (CC-IBI) determined for 1998‒2013 was evaluated for the five biological sampling sites collocated with streamgages. CC-IBI scores are based on a 0‒100 scale with higher scores indicating better stream quality. Statistically significant upward trends in the CC-IBI were determined for West Branch Brandywine Creek at Modena, Pa. (01480617) and East Branch Brandywine Creek below Downingtown, Pa. (01480870). No correlation was found between the CC-IBI and streamflow, precipitation, or stream specific conductance, pH, temperature, or dissolved oxygen concentration.A Chester County average water budget was developed using the nine estimated watershed water budgets. Average precipitation was 48.4 inches, and average streamflow was 21.4 inches. Average runoff and base flow were 8.3 and 13.1 inches, respectively, and average evapotranspiration and estimation of errors was 27.2 inches."

Water bicarbonate modulates the response of the shore crab Carcinus maenas to ocean acidification.

PubMed

Maus, Bastian; Bock, Christian; Pörtner, Hans-O

2018-05-23

Ocean acidification causes an accumulation of CO 2 in marine organisms and leads to shifts in acid-base parameters. Acid-base regulation in gill breathers involves a net increase of internal bicarbonate levels through transmembrane ion exchange with the surrounding water. Successful maintenance of body fluid pH depends on the functional capacity of ion-exchange mechanisms and associated energy budget. For a detailed understanding of the dependence of acid-base regulation on water parameters, we investigated the physiological responses of the shore crab Carcinus maenas to 4 weeks of ocean acidification [OA, P(CO 2 ) w  = 1800 µatm], at variable water bicarbonate levels, paralleled by changes in water pH. Cardiovascular performance was determined together with extra-(pH e ) and intracellular pH (pH i ), oxygen consumption, haemolymph CO 2 parameters, and ion composition. High water P(CO 2 ) caused haemolymph P(CO 2 ) to rise, but pH e and pH i remained constant due to increased haemolymph and cellular [HCO 3 - ]. This process was effective even under reduced seawater pH and bicarbonate concentrations. While extracellular cation concentrations increased throughout, anion levels remained constant or decreased. Despite similar levels of haemolymph pH and ion concentrations under OA, metabolic rates, and haemolymph flow were significantly depressed by 40 and 30%, respectively, when OA was combined with reduced seawater [HCO 3 - ] and pH. Our findings suggest an influence of water bicarbonate levels on metabolic rates as well as on correlations between blood flow and pH e . This previously unknown phenomenon should direct attention to pathways of acid-base regulation and their potential feedback on whole-animal energy demand, in relation with changing seawater carbonate parameters.

Adaptation of farming practices could buffer effects of climate change on northern prairie wetlands

USGS Publications Warehouse

Voldseth, R.A.; Johnson, W.C.; Guntenspergen, G.R.; Gilmanov, T.; Millett, B.V.

2009-01-01

Wetlands of the Prairie Pothole Region of North America are vulnerable to climate change. Adaptation of farming practices to mitigate adverse impacts of climate change on wetland water levels is a potential watershed management option. We chose a modeling approach (WETSIM 3.2) to examine the effects of changes in climate and watershed cover on the water levels of a semi-permanent wetland in eastern South Dakota. Land-use practices simulated were unmanaged grassland, grassland managed with moderately heavy grazing, and cultivated crops. Climate scenarios were developed by adjusting the historical climate in combinations of 2??C and 4??C air temperature and ??10% precipitation. For these climate change scenarios, simulations of land use that produced water levels equal to or greater than unmanaged grassland under historical climate were judged to have mitigative potential against a drier climate. Water levels in wetlands surrounded by managed grasslands were significantly greater than those surrounded by unmanaged grassland. Management reduced both the proportion of years the wetland went dry and the frequency of dry periods, producing the most dynamic vegetation cycle for this modeled wetland. Both cultivated crops and managed grassland achieved water levels that were equal or greater than unmanaged grassland under historical climate for the 2??C rise in air temperature, and the 2??C rise plus 10% increase in precipitation scenarios. Managed grassland also produced water levels that were equal or greater than unmanaged grassland under historical climate for the 4??C rise plus 10% increase in precipitation scenario. Although these modeling results stand as hypotheses, they indicate that amelioration potential exists for a change in climate up to an increase of 2??C or 4??C with a concomitant 10% increase in precipitation. Few empirical data exist to verify the results of such land-use simulations; however, adaptation of farming practices is one possible mitigation avenue available for prairie wetlands. ?? 2009, The Society of Wetland Scientists.

Nutrient and carbon availability influences on denitrification in the regulated Lower Colorado River, Austin

NASA Astrophysics Data System (ADS)

Spector, J.

2016-12-01

The Lower Colorado River in Austin, Texas receives nitrogen-rich runoff and treated wastewater effluent and is subject to periodic water releases from the Longhorn Dam, which cause fluctuations in groundwater stage downstream. This research examined groundwater denitrification at the Hornsby Bend riparian area (located approximately 24 km downstream of downtown Austin) and characterized how dam-induced hyporheic exchange affects denitrification rates. Conductivity, temperature, water level, and dissolved oxygen concentrations were measured continuously throughout flood pulses for six months using dataloggers installed in a transect of seven monitoring wells on the river bank. Hourly samples were collected using an autosampler in one monitoring well (MW-5) during various flood conditions during the six month monitoring period. Water samples were analyzed for total organic carbon, total nitrogen, anions (NO3- and NO2-), NH4+ concentrations, alkalinity, and specific ultraviolet absorbance (SUVA) to characterize dissolved organic matter. Following large flood events (up to 4 m of water level stage increase), average conductivity increased 300 µs/centimeter in MW-5 as the water level receded. Analysis of water samples indicated that NO3- reduction occurred as conductivity and alkalinity increased. In addition, NH4+ concentrations increased during high conductivity periods. Increased denitrification activity corresponded with high SUVA. High conductivity and alkalinity increase the availability of electron donors (HCO3- and CO32-) and enhances denitrification potential. Higher SUVA values indicate increased dissolved organic carbon aromaticity and corresponding NO3- reduction. Additionally, changes in dissolved organic matter lability indicate the residence times of possible reactive organic carbon in the riparian area. This study has implications for determining advantageous geochemical conditions for hyporheic zone denitrification following large flood events.

Carbon Dioxide and Water Vapor Fluxes at Reduced and Elevated CO2 Concentrations in Southern California Chaparral

NASA Astrophysics Data System (ADS)

Cheng, Y.; Oechel, W. C.; Hastings, S. J.; Bryant, P. J.; Qian, Y.

2003-12-01

This research took two different approaches to measuring carbon and water vapor fluxes at the plot level (2 x 2 meter and 1 x 1 meter plots) to help understand and predict ecosystem responses to elevated CO2 concentrations and concomitant environmental changes. The first measurement approach utilized a CO2-controlled, ambient lit, temperature controlled (CO2LT) null-balance chamber system run in a chaparral ecosystem in southern California, with six different CO2 concentrations ranging from 250 to 750 ppm CO2 concentrations with 100 ppm difference between treatments. The second measurement approach used a free air CO2 enrichment (FACE) system operated at 550 ppm CO2 concentration. These manipulations allowed the study of responses of naturally-growing chaparral to varying levels of CO2, under both chamber and open air conditions. There was a statistically significant CO2 effect on annual NEE (net ecosystem exchange) during the period of this study, 1997 to 2000. The effects of elevated CO2 on CO2 and water vapor flux showed strong seasonal patterns. Elevated CO2 delayed the development of water stress, enhanced leaf-level photosynthesis, and decreased transpiration and conductance rates. These effects were observed regardless of water availability. Ecosystem CO2 sink strength and plant water status were significantly enhanced by elevated CO2 when water availability was restricted. Comparing the FACE treatment and the FACE control, the ecosystem was either a stronger sink or a weaker source to the atmosphere throughout the dry seasons, but there was no statistically significant difference during the wet seasons. Annual average leaf transpiration decreased with the increasing of the atmospheric CO2 concentration. Although leaf level water-use efficiency (WUE) increased with the growth CO2 concentration increase, annual evapotranspiration (ET) during these four years also increased with the increase of the atmospheric CO2 concentrations. These results indicate that chaparral or other similar ecosystems, under future elevated CO2 concentrations, might be even more water stressed than they are under current conditions.

Potentiometric Surface of the Ozark Aquifer in Northern Arkansas, 2007

USGS Publications Warehouse

Pugh, Aaron L.

2008-01-01

The Ozark aquifer in northern Arkansas is composed of dolomite, limestone, sandstone, and shale of Late Cambrian to Middle Devonian age, and ranges in thickness from approximately 1,100 feet to more than 4,000 feet. Hydrologically, the aquifer is complex, characterized by discrete and discontinuous flow components with large variations in permeability. The potentiometric-surface map, based on 58 well and 5 spring water-level measurements collected in 2007 in Arkansas and Missouri, has a maximum water-level altitude measurement of 1,169 feet in Carroll County and a minimum water-level altitude measurement of 118 feet in Randolph County. Regionally, the flow within the aquifer is to the south and southeast in the eastern and central part of the study area and to the west, northwest, and north in the western part of the study area. Comparing the 2007 potentiometric-surface map with a predevelopment potentiometric-surface map indicates general agreement between the two surfaces except in the northwestern part of the study area. Potentiometric-surface differences can be attributed to withdrawals related to increasing population, changes in public-supply sources, processes or water withdrawals outside the study area, or differences in data-collection or map-construction methods. The rapidly increasing population within the study area appears to have some effect on ground-water levels. Although, the effect appears to have been minimized by the development and use of surface-water distribution infrastructure, suggesting most of the incoming populations are fulfilling their water needs from surface-water sources. The conversion of some users from ground water to surface water may be allowing water levels in wells to recover (rise) or decline at a slower rate, such as in Benton, Carroll, and Washington Counties.

Towards a global water scarcity risk assessment framework: using scenarios and risk distributions

NASA Astrophysics Data System (ADS)

Veldkamp, Ted; Wada, Yoshihide; Aerts, Jeroen; Ward, Philip

2016-04-01

Over the past decades, changing hydro-climatic and socioeconomic conditions have led to increased water scarcity problems. A large number of studies have shown that these water scarcity conditions will worsen in the near future. Despite numerous calls for risk-based assessments of water scarcity, a framework that includes UNISDR's definition of risk does not yet exist at the global scale. This study provides a first step towards such a risk-based assessment, applying a Gamma distribution to estimate water scarcity conditions at the global scale under historic and future conditions, using multiple climate change projections and socioeconomic scenarios. Our study highlights that water scarcity risk increases given all future scenarios, up to >56.2% of the global population in 2080. Looking at the drivers of risk, we find that population growth outweigh the impacts of climate change at global and regional scales. Using a risk-based method to assess water scarcity in terms of Expected Annual Exposed Population, we show the results to be less sensitive than traditional water scarcity assessments to the use of fixed threshold to represent different levels of water scarcity. This becomes especially important when moving from global to local scales, whereby deviations increase up to 50% of estimated risk levels. Covering hazard, exposure, and vulnerability, risk-based methods are well-suited to assess water scarcity adaptation. Completing the presented risk framework therefore offers water managers a promising perspective to increase water security in a well-informed and adaptive manner.

Water-level data for the Albuquerque Basin and adjacent areas, central New Mexico, period of record through September 30, 2009

USGS Publications Warehouse

Beman, Joseph E.; Torres, Leeanna T.

2010-01-01

The Albuquerque Basin, located in central New Mexico, is about 100 miles long and 25 to 40 miles wide. The basin is defined as the extent of consolidated and unconsolidated deposits of Tertiary and Quaternary age that encompass the structural Rio Grande Rift within the basin. Drinking-water supplies throughout the basin were obtained solely from groundwater resources until December 2008, when surface water from the Rio Grande began being treated and integrated into the system. An increase of about 20 percent in the population from 1990 to 2000 also resulted in an increased demand for water. A network of wells was established to monitor changes in groundwater levels throughout the basin from April 1982 through September 1983. This network consisted of 6 wells with analog-to-digital recorders and 27 wells where water levels were measured monthly in 1983. Currently (2009), the network consists of 131 wells and piezometers. This report presents water-level data collected by U.S. Geological Survey personnel at 123 sites through water year 2009. In addition, data from four wells (Sites 140, 147, 148, and 149) owned, maintained, and measured by Sandia National Laboratories and three from Kirtland Air Force Base (Sites 119, 125, and 126) are presented in this report.

Simulation of the effects of development of the ground-water flow system of Long Island, New York

USGS Publications Warehouse

Buxton, Herbert T.; Smolensky, Douglas A.

1999-01-01

Extensive development on Long Island since the late 19th century and projections of increased urbanization and ground-water use makes effective water-resource management essential for preservation of the island's hydrologic environment and maintenance of a reliable source of water supply. This report presents results of a ground-water flow simulation analysis of the effects of development on the Long Island ground-water system. It describes ground-water levels, stream-flow, and the ground-water budget for the predevelopment period (pre-1900), the 1960's drought, and a more recent (1968-83) period with significant hydrologic stress. The report also presents estimated effects of a proposed water-supply strategy for the year 2020. Long Island has three major aquifers-the upper glacial (water-table), the Magothy, and the Lloyd aquifers-that are separated to varying degrees by confining units. Before development, recharge from precipitation entered the ground-water system at a rate of more than 1.1 billion gallons per day. An equal amount discharged to streams (41 percent), the shore (52 percent), and subsea boundaries (7 percent) . Urbanization and withdrawal of more than 400 Mgal/d (million gallons per day) from wells have resulted in local effects that include declines in ground-water levels, drying up and burial of streams and wetlands, reduction of ground-water recharge by increased overland flow to the ocean, a general decrease in ground-water discharge, and salt water intrusion. In some areas, the reduction in recharge is mitigated by leakage from water-supply and wastewater disposal lines, and infiltration of storm water through recharge basins. During 1968-83, a net loss of 240 Mgal/d from the ground-water system caused a decrease in ground-water discharge to streams (135 Mgal/d), to the shore (82 Mgal/d), and to subsea boundaries (23Mgal/d).The greatest adverse effects have been in western Long Island, where the most severe development has occurred. This analysis shows stream base flow to be highly sensitive to water-table fluctuations, and long streams to be more sensitive than short ones. A water-supply scenario for the year 2020 was simulated that employs redistribution of pumping centers to mitigate extreme local effects . Although the net stress on the ground-water system was projected to increase 57 Mgal/d (24 percent) above that of 1968-83, redistribution of ground-water withdrawals across the island would allow recovery of cones of depression in western Long Island, thereby reducing the threat of salt water intrusion and increasing base flow of some streams . The increased stress would cause a net decrease in base flow island wide of 44 Mgal/d; total base flow would be 281 Mgal/d - 39 percent below predevelopment levels or 14 percent below 1968-83 levels. The most severe effects would be in Nassau and western Suffolk Counties.

Effect of food preparation using naturally-contaminated groundwater from La Pampa, Argentina: Estimation of elemental dietary intake from rice and drinking water.

PubMed

Jaafar, Maisarah; Marcilla, Andrea L; Felipe-Sotelo, Mónica; Ward, Neil I

2018-04-25

Water from La Pampa, Argentina, was used for washing and cooking rice to examine the in-situ impact of using naturally-contaminated water for food preparation on the elemental dietary intake. Whilst washing with the control tap water (28 μg/L As) reduced the concentration of As in rice by 23%, the use of different well waters (281-1144 μg/L) increased As levels significantly (48-227%) in comparison with the original concentration in the rice (0.056 µg/g). Cooking the rice at a low water-to-rice ratio (2:1) using modern methods increased the levels of As in the cooked samples by 2-3 orders of magnitude for both pre-washed and un-washed rice. Similar trends were observed for vanadium. Although the levels of manganese, iron, copper, zinc and molybdenum in rice were reduced during washing and cooking for most water samples, the molybdenum concentration in the cooked rice doubled (2.2-2.9 µg/g) when using water containing >1 mg/L Mo. Copyright © 2017 Elsevier Ltd. All rights reserved.

The U.S. Geological Survey and City of Atlanta water-quality and water-quantity monitoring network

USGS Publications Warehouse

Horowitz, Arthur J.; Hughes, W. Brian

2006-01-01

Population growth and urbanization affect the landscape, and the quality and quantity of water in nearby rivers and streams, as well as downstream receiving waters (Ellis, 1999). Typical impacts include: (1) disruption of the hydrologic cycle through increases in the extent of impervious surfaces (e.g., roads, roofs, sidewalks) that increase the velocity and volume of surface-water runoff; (2) increased chemical loads to local and downstream receiving waters from industrial sources, nonpoint-source runoff, leaking sewer systems, and sewer overflows; (3) direct or indirect soil contamination from industrial sources, power-generating facilities, and landfills; and (4) reduction in the quantity and quality of aquatic habitats. The City of Atlanta's monitoring network consists of 21 long-term sites. Eleven of these are 'fully instrumented' to provide real-time data on water temperature, pH, specific conductance, dissolved oxygen, turbidity (intended as a surrogate for suspended sediment concentration), water level (gage height, intended as a surrogate for discharge), and precipitation. Data are transmitted hourly and are available on a public Web site (http://ga.water.usgs.gov/). Two sites only measure water level and rainfall as an aid to stormwater monitoring. The eight remaining sites are used to assess water quality.

Wastewater application by spray irrigation on a field southeast of Tallahassee, Florida; effects on ground-water quality and quantity, 1980-82

USGS Publications Warehouse

Elder, J.F.; Hunn, J.D.; Calhoun, C.W.

1985-01-01

A field southeast of Tallahassee, Florida, used for land application of wastewater by spray irrigation was the site of a ground-water monitoring study to determine effects of spray irrigation on water-table elevations and ground-water quality. The study was conducted during 1980-82 in cooperation with the City of Tallahassee. The wastewater has relatively high concentrations of chloride, nitrogen, phosphorus, organic carbon , coliform bacteria, sodium, and potassium. These substances are usually attenuated before they can impact the ground water. However, increases in chloride and nitrate-nitrogen were evident in ground water in some of the monitoring wells during the study. Chloride concentrations increased five-fold or more in some wells directly affected by spray irrigation, and nitrate-nitrogen concentrations increased eight-fold or more. Ground-water levels in the area of the spray field fluctuated over a range of several feet. These fluctuations were affected somewhat by spray irrigation, but the primary control on water levels was rainfall. As of December 1982, constituents introduced to the system by spray irrigation of effluent had not exceeded drinking water standard in the ground water. However, the system had not yet stabilized and more changes in ground-water quality could be expected. (USGS)

Evaluation of handheld assays for the detection of ricin and staphylococcal enterotoxin B in disinfected waters.

PubMed

Wade, Mary Margaret; Biggs, Tracey D; Insalaco, Joseph M; Neuendorff, Lisa K; Bevilacqua, Vicky L H; Schenning, Amanda M; Reilly, Lisa M; Shah, Saumil S; Conley, Edward K; Emanuel, Peter A; Zulich, Alan W

2011-01-01

Development of a rapid field test is needed capable of determining if field supplies of water are safe to drink by the warfighter during a military operation. The present study sought to assess the effectiveness of handheld assays (HHAs) in detecting ricin and Staphylococcal Enterotoxin B (SEB) in water. Performance of HHAs was evaluated in formulated tap water with and without chlorine, reverse osmosis water (RO) with chlorine, and RO with bromine. Each matrix was prepared, spiked with ricin or SEB at multiple concentrations, and then loaded onto HHAs. HHAs were allowed to develop and then read visually. Limits of detection (LOD) were determined for all HHAs in each water type. Both ricin and SEB were detected by HHAs in formulated tap water at or below the suggested health effect levels of 455 ng/mL and 4.55 ng/mL, respectively. However, in brominated or chlorinated waters, LODs for SEB increased to approximately 2,500 ng/mL. LODs for ricin increased in chlorinated water, but still remained below the suggested health effect level. In brominated water, the LOD for ricin increased to approximately 2,500 ng/mL. In conclusion, the HHAs tested were less effective at detecting ricin and SEB in disinfected water, as currently configured.

Hydrogeology of shallow basin-fill deposits in areas of Salt Lake Valley, Salt Lake County, Utah

USGS Publications Warehouse

Thiros, Susan A.

2003-01-01

A study of recently developed residential/commercial areas of Salt Lake Valley, Utah, was done from 1999 to 2001 in areas in which shallow ground water has the potential to move to a deeper aquifer that is used for public supply. Thirty monitoring wells were drilled and sampled in 1999 as part of the study. The ground water was either under unconfined or confined conditions, depending on depth to water and the presence or absence of fine-grained deposits. The wells were completed in the shallowest water-bearing zone capable of supplying water. Monitoring-well depths range from 23 to 154 feet. Lithologic, geophysical, hydraulic-conductivity, transmissivity, water-level, and water-temperature data were obtained for or collected from the wells.Silt and clay layers noted on lithologic logs correlate with increases in electrical conductivity and natural gamma radiation shown on many of the electromagnetic-induction and natural gamma logs. Relatively large increases in electrical conductivity, determined from the electromagnetic-induction logs, with no major changes in natural gamma radiation are likely caused by increased dissolved-solids content in the ground water. Some intervals with high electrical conductivity correspond to areas in which water was present during drilling.Unconfined conditions were present at 7 of 20 monitoring wells on the west side and at 2 of 10 wells on the east side of Salt Lake Valley. Fine-grained deposits confine the ground water. Anthropogenic compounds were detected in water sampled from most of the wells, indicating a connection with the land surface. Data were collected from 20 of the monitoring wells to estimate the hydraulic conductivity and transmissivity of the shallow ground-water system. Hydraulic-conductivity values of the shallow aquifer ranged from 30 to 540 feet per day. Transmissivity values of the shallow aquifer ranged from 3 to 1,070 feet squared per day. There is a close linear relation between transmissivity determined from slug-test analysis and transmissivity estimated from specific capacity.Water-level fluctuations were measured in the 30 monitoring wells from 1999 to July 2001. Generally, water-level changes measured in wells on the west side of the valley followed a seasonal trend and wells on the east side showed less fluctuation or a gradual decline during the 2-year period. This may indicate that a larger percentage of recharge to the shallow ground-water system on the west side is from somewhat consistent seasonal sources, such as canals and unconsumed irrigation water, as compared to sources on the east side. Water levels measured in monitoring wells completed in the shallow ground-water system near large-capacity public-supply wells varied in response to ground-water withdrawals from the deeper confined aquifer. Water temperature was monitored in 23 wells. Generally, little or no change in water temperature was measured in monitoring wells with a depth to water greater than about 40 feet. The shallower the water level in the well, the greater the water-temperature change measured during the study.Comparison of water levels measured in the monitoring wells and deeper wells in the same area indicate a downward gradient on the east side of the valley. Water levels in the shallow and deeper aquifers in the secondary recharge area on the west side of the valley were similar to those on the east side. Water levels measured in the monitoring wells and nearby wells completed in the deeper aquifer indicate that the vertical gradient can change with time and stresses on the system.

Increased Water Storage in the Qaidam Basin, the North Tibet Plateau from GRACE Gravity Data

PubMed Central

Jiao, Jiu Jimmy; Zhang, Xiaotao; Liu, Yi; Kuang, Xingxing

2015-01-01

Groundwater plays a key role in maintaining the ecology and environment in the hyperarid Qaidam Basin (QB). Indirect evidence and data from sparse observation wells suggest that groundwater in the QB is increasing but there has been no regional assessment of the groundwater conditions in the entire basin because of its remoteness and the severity of the arid environment. Here we report changes in the spatial and temporal distribution of terrestrial water storage (TWS) in the northern Tibetan Plateau (NTP) using Gravity Recovery and Climate Experiment (GRACE) data. Our study confirms long-term (2003–2012) TWS increases in the NTP. Between 2003 and 2012 the TWS increased by 88.4 and 20.6 km3 in the NTP and the QB, respectively, which is 225% and 52% of the capacity of the Three Gorges Reservoir, respectively. Soil and water changes from the Global Land Data Assimilation System (GLDAS) were also used to identify groundwater storage in the TWS and to demonstrate a long-term increase in groundwater storage in the QB. We demonstrate that increases in groundwater, not lake water, are dominant in the QB, as observed by groundwater levels. Our study suggests that the TWS increase was likely caused by a regional increase in precipitation and a decrease in evaporation. Degradation of the permafrost increases the thickness of the active layers providing increased storage for infiltrated precipitation and snow and ice melt water, which may also contribute to the increased TWS. The huge increase of water storage in the NTP will have profound effects, not only on local ecology and environment, but also on global water storage and sea level changes. PMID:26506230

Increased Water Storage in the Qaidam Basin, the North Tibet Plateau from GRACE Gravity Data.

PubMed

Jiao, Jiu Jimmy; Zhang, Xiaotao; Liu, Yi; Kuang, Xingxing

2015-01-01

Groundwater plays a key role in maintaining the ecology and environment in the hyperarid Qaidam Basin (QB). Indirect evidence and data from sparse observation wells suggest that groundwater in the QB is increasing but there has been no regional assessment of the groundwater conditions in the entire basin because of its remoteness and the severity of the arid environment. Here we report changes in the spatial and temporal distribution of terrestrial water storage (TWS) in the northern Tibetan Plateau (NTP) using Gravity Recovery and Climate Experiment (GRACE) data. Our study confirms long-term (2003-2012) TWS increases in the NTP. Between 2003 and 2012 the TWS increased by 88.4 and 20.6 km3 in the NTP and the QB, respectively, which is 225% and 52% of the capacity of the Three Gorges Reservoir, respectively. Soil and water changes from the Global Land Data Assimilation System (GLDAS) were also used to identify groundwater storage in the TWS and to demonstrate a long-term increase in groundwater storage in the QB. We demonstrate that increases in groundwater, not lake water, are dominant in the QB, as observed by groundwater levels. Our study suggests that the TWS increase was likely caused by a regional increase in precipitation and a decrease in evaporation. Degradation of the permafrost increases the thickness of the active layers providing increased storage for infiltrated precipitation and snow and ice melt water, which may also contribute to the increased TWS. The huge increase of water storage in the NTP will have profound effects, not only on local ecology and environment, but also on global water storage and sea level changes.

Hydrology and water quality of Shell Lake, Washburn County, Wisconsin, with special emphasis on the effects of diversion and changes in water level on the water quality of a shallow terminal lake

USGS Publications Warehouse

Juckem, Paul F.; Robertson, Dale M.

2013-01-01

Shell Lake is a relatively shallow terminal lake (tributaries but no outlets) in northwestern Wisconsin that has experienced approximately 10 feet (ft) of water-level fluctuation over more than 70 years of record and extensive flooding of nearshore areas starting in the early 2000s. The City of Shell Lake (City) received a permit from the Wisconsin Department of Natural Resources in 2002 to divert water from the lake to a nearby river in order to lower water levels and reduce flooding. Previous studies suggested that water-level fluctuations were driven by long-term cycles in precipitation, evaporation, and runoff, although questions about the lake’s connection with the groundwater system remained. The permit required that the City evaluate assumptions about lake/groundwater interactions made in previous studies and evaluate the effects of the water diversion on water levels in Shell Lake and other nearby lakes. Therefore, a cooperative study between the City and U.S. Geological Survey (USGS) was initiated to improve the understanding of the hydrogeology of the area and evaluate potential effects of the diversion on water levels in Shell Lake, the surrounding groundwater system, and nearby lakes. Concerns over deteriorating water quality in the lake, possibly associated with changes in water level, prompted an additional cooperative project between the City and the USGS to evaluate efeffects of changes in nutrient loading associated with changes in water levels on the water quality of Shell Lake. Numerical models were used to evaluate how the hydrology and water quality responded to diversion of water from the lake and historical changes in the watershed. The groundwater-flow model MODFLOW was used to simulate groundwater movement in the area around Shell Lake, including groundwater/surface-water interactions. Simulated results from the MODFLOW model indicate that groundwater flows generally northward in the area around Shell Lake, with flow locally converging toward the lake. Total groundwater inflow to Shell Lake is small (approximately 5 percent of the water budget) compared with water entering the lake from precipitation (83 percent) and surface-water runoff (13 percent). The MODFLOW model also was used to simulate average annual hydrologic conditions from 1949 to 2009, including effects of the removal of 3 billion gallons of water during 2003–5. The maximum decline in simulated average annual water levels for Shell Lake due to the diversion alone was 3.3 ft at the end of the diversion process in 2005. Model simulations also indicate that although water level continued to decline through 2009 in response to local weather patterns (local drought), the effects of the diversion decreased after the diversion ceased; that is, after 4 years of recovery (2006–9), drawdown attributable to the diversion alone decreased by about 0.6 ft because of increased groundwater inflow and decreased lake-water outflow to groundwater caused by the artificially lower lake level. A delayed response in drawdown of less than 0.5 ft was transmitted through the groundwater-flow system to upgradient lakes. This relatively small effect on upgradient lakes is attributed in part to extensive layers of shallow clay that limit lake/groundwater interaction in the area. Data collected in the lake indicated that Shell Lake is polymictic (characterized by frequent deep mixing) and that its productivity is limited by the amount of phosphorus in the lake. The lake was typically classified as oligotrophic-mesotrophic in June, mesotrophic in July, and mesotrophic-eutrophic in August. In polymictic lakes like Shell Lake, phosphorus released from the sediments is not trapped near the bottom of the lake but is intermittently released to the shallow water, resulting in deteriorating water quality as summer progresses. Because the productivity of Shell Lake is limited by phosphorus, the sources of phosphorus to the lake were quantified, and the response in water quality to changes in phosphorus inputs were evaluated by means of eutrophication models. During 2009, the total input of phosphorus to Shell Lake was 1,730 pounds (lb), of which 1,320 lb came from external sources (76 percent) and 414 lb came from internal loading from sediments in the lake (24 percent). The largest external source was from surface-water runoff, which delivered about 52 percent of the total phosphorus load compared with about 13 percent of the water input. The second largest source was from precipitation (wetfall and dryfall), which delivered 19 percent of the load compared to about 83 percent of the water input. Contributions from septic systems and groundwater accounted for about 3 and 2 percent, respectively. Increased runoff raises water levels in the lake but does not necessarily increase phosphorus loading because phosphorus concentrations in the tributaries decline during increased flow, possibly because of shorter retention times in upstream wetlands. Phosphorus loading to the lake in 2009 represented what occurred after a series of dry years; therefore, this information was combined with data from 2011, a wet year, to estimate phosphorus loading during a range of hydrologic conditions by estimating loading from each component of the phosphorus budget for each year from 1949 to 2011. Comparisons of historical water-quality records with historical water levels and applications of a hydrodynamic model (Dynamic Lake Model, DLM) and empirical eutrophication models were used to understand how changes in water level and the coinciding changes in phosphorus loading affect the water quality of Shell Lake. DLM simulations indicate that large changes in water level (approximately 10 ft) affect the persistence of stratification in the lake. During periods with low water levels, the lake is a well-mixed, polymictic system, with water quality degrading slightly as summer progresses. During periods with high water levels, the lake is more stratified, and phosphorus from internal loading is trapped in the hypolimnion and released later in summer, which results in more extreme seasonality in water quality and better clarity in early summer. Results of eutrophication model simulations using a range in external phosphorus inputs illustrate how water quality in Shell Lake (phosphorus and chlorophyll a concentrations and Secchi depths) responds to changes in external phosphorus loading. Results indicate that a 50-percent reduction in external loading from that measured in 2009 would be required to change phosphorus concentrations from 0.018 milligram per liter (mg/L) (measured in 2009) to 0.012 mg/L (estimated for the mid-1800s from analysis of diatoms in sediment cores). Such reductions in phosphorus loading cannot be accomplished by targeting septic systems or internal loading alone because septic systems contribute only about 3 percent of the phosphorus input to the lake, and internal loading from the sediments of Shell Lake contributes only about 25 percent of phosphorus input. Complete elimination of phosphorus from septic systems and internal loading would decrease the phosphorus concentrations in the lake by 0.003–0.004 mg/L. Therefore, reducing phosphorus concentration in the lake more than by 0.004 mg/L requires decreasing phosphorus loading from surface-water contributions, primarily runoff to the lake. Reconstructed changes in water quality from 1860 to 2010, based on changes in the diatom communities archived in the sediments and eutrophication model simulations, suggest that anthropogenic changes in the watershed (sawmill construction in 1881; the establishment of the village of Shell Lake; and land-use changes in the 1920s, including increased agriculture) had a much larger effect on water quality than the natural changes associated with fluctuations in water level. Although the effects of natural changes in water level on water quality appear to be small, changes in water level do have a modest effect on water quality, primarily manifested as small improvements during higher water levels. Fluctuations in water level, however, have a larger effect on the seasonality of water-quality patterns, with better water quality, especially increased Secchi depths, in early summer during years with high water levels.

Measures of Groundwater Drought from the Long-term Monitoring Data in Korea

NASA Astrophysics Data System (ADS)

Chung, E.; Park, J.; Woo, N. C.

2017-12-01

Recently, drought has been increased in its severity and frequency along the climate change in Korea. There are several criteria for alarming drought, for instance, based on the no-rainfall days, the amount of stream discharge, and the water levels of reservoirs. However, farmers depending on groundwater still have been suffered in preparing drought especially in the Spring. No-rainfall days continue, groundwater exploitation increases, water table declines, stream discharge decreases, and then the effects of drought become serious. Thus, the drought index based on the groundwater level is needed for the preparedness of drought disaster. Palmer et al.(1965, USGS) has proposed a method to set the threshold for the decline of the groundwater level in 5 stages based on the daily water-level data over the last 30 years. In this study, according to Peters et al.(2003), the threshold of groundwater level was estimated using the daily water-level data at five sites with significant drought experiences in Korea. Water levels and precipitations data were obtained from the national groundwater monitoring wells and the automatic weather stations, respectively, for 10 years from 2005 to 2014. From the water-level changes, the threshold was calculated when the value of the drought criterion (c), the ratio of the deficit below the threshold to the deficit below the average, is 0.3. As a result, the monthly drought days were high in 2009 and 2011 in Uiryeong, and from 2005 to 2008 in Boeun. The validity of the approach and the threshold can be evaluated by comparing calculated monthly drought days with recorded drought in the past. Through groundwater drought research, it is expected that not only surface water also groundwater resource management should be implemented more efficiently to overcome drought disaster.

Is fluoride a risk factor for bone cancer? Small area analysis of osteosarcoma and Ewing sarcoma diagnosed among 0-49-year-olds in Great Britain, 1980-2005.

PubMed

Blakey, Karen; Feltbower, Richard G; Parslow, Roger C; James, Peter W; Gómez Pozo, Basilio; Stiller, Charles; Vincent, Tim J; Norman, Paul; McKinney, Patricia A; Murphy, Michael F; Craft, Alan W; McNally, Richard J Q

2014-02-01

Artificial fluoridation of drinking water to improve dental health has long been a topic of controversy. Opponents of this public health measure have cited the possibility of bone cancer induction. The study objective was to examine whether increased risk of primary bone cancer was associated with living in areas with higher concentrations of fluoride in drinking water. Case data on osteosarcoma and Ewing sarcoma, diagnosed at ages 0-49 years in Great Britain (GB) (defined here as England, Scotland and Wales) during the period 1980-2005, were obtained from population-based cancer registries. Data on fluoride levels in drinking water in England and Wales were accessed through regional water companies and the Drinking Water Inspectorate. Scottish Water provided data for Scotland. Negative binomial regression was used to examine the relationship between incidence rates and level of fluoride in drinking water at small area level. The study analysed 2566 osteosarcoma and 1650 Ewing sarcoma cases. There was no evidence of an association between osteosarcoma risk and fluoride in drinking water [relative risk (RR) per one part per million increase in the level of fluoride = 1·001; 90% confidence interval (CI) 0·871, 1·151] and similarly there was no association for Ewing sarcoma (RR = 0·929; 90% CI 0·773, 1·115). The findings from this study provide no evidence that higher levels of fluoride (whether natural or artificial) in drinking water in GB lead to greater risk of either osteosarcoma or Ewing sarcoma.

Public participation in water resources management: Restructuring model of upstream Musi watershed

NASA Astrophysics Data System (ADS)

Andriani, Yuli; Zagloel, T. Yuri M.; Koestoer, R. H.; Suparmoko, M.

2017-11-01

Water is the source of life needed by living things. Human as one of living most in needs of water. Because the population growth follows the geometrical progression, while the natural resource increases calculates the arithmetic. Humans besides needing water also need land for shelter and for their livelihood needs, such as gardening or rice farmers. If the water absorption area is reduced, water availability will decrease. Therefore it is necessary to conduct an in-depth study of water resources management involving the community. The purpose of this study is to analyze community participation in water resources management, so that its availability can still meet the needs of living and sustainable. The method that used the level of community participation according to Arstein theory. The results obtained that community participation is at the level of partnership and power delegation. This level of participation is at the level of participation that determines the sustainability of water resources for present and future generations.

CAN FLUORIDATION AFFECT WATER LEAD LEVELS AND LEAD NEUROTOXICITY?

EPA Science Inventory

Recent reports have attempted to show that certain approaches to fluoridating potable water is linked to increased levels of lead(II) in the blood. We examine these claims in light of the established science and critically evaluate their significance. The completeness of nexafluo...

SMALL SCALE ECOSYSTEM ENGINEERING: DEVELOPMENT OF HOUSEHOLD LEVEL GREYWATER TREATMENT SYSTEMS

EPA Science Inventory

The project will increase quality of life through the protection of ecosystem services and drinking water supplies through pollution reduction. Additionally, through water reuse our project has the potential to decrease overall water consumption. Decreasing overall water co...

Analysis for water level data for Everglades National Park, Florida

USGS Publications Warehouse

Buchanan, T.J.; Hartwell, J.H.

1972-01-01

Stage-duration curves were developed for five gaging stations in Everglades National Park, Florida. Four of the five curves show similar characteristics with an increase in the slope when the water level is below land surface. Monthly stage-duration curves, developed for one of the stations, reflect the seasonal trends of the water level. Recession curves were prepared for the same five stations. These curves represent the average water-level decline during periods of little or no rainfall. They show the decline in level at the end of 10, 20, and 60 days for any given initial stage. A family of curves was also prepared to give the recession from various initial stages for any period up to 60 days.

Four phases of the Flint Water Crisis: Evidence from blood lead levels in children.

PubMed

Zahran, Sammy; McElmurry, Shawn P; Sadler, Richard C

2017-08-01

The Flint Water Crisis (FWC) is divisible into four phases of child water-lead exposure risk: Phase A) before the switch in water source to the Flint River (our baseline); Phase B) after the switch in water source, but before boil water advisories; Phase C) after boil water advisories, but before the switch back to the baseline water source of the Detroit Water and Sewerage Department (DWSD); and Phase D) after the switch back to DWSD. The objective of this work is to estimate water-lead attributable movements in child blood lead levels (BLLs) that correspond with the four phases in the FWC. With over 21,000 geo-referenced and time-stamped blood lead samples from children in Genesee County drawn from January 01, 2013 to July 19, 2016, we develop a series of quasi-experimental models to identify the causal effect of water-lead exposure on child BLLs in Flint. We find that the switch in water source (transitioning from phase A to B) caused mean BLLs to increase by about 0.5μg/dL, and increased the likelihood of a child presenting with a BLL ≥ 5μg/dL by a factor of 1.91-3.50, implying an additional 561 children exceeding 5μg/dL. We conservatively estimate cohort social costs (through lost earnings alone) of this increase in water-lead exposed children at $65 million, contrasted with expected annual savings of $2 million from switching water source. On the switch from Phase B to C, we find BLLs decreased about 50% from their initial rise following boil water advisories and subsequent water avoidance behaviors by households. Finally, the return to the baseline source water (Phase D) returned child BLLs to pre-FWC levels further implicating water-lead exposure as a causal source of child BLLs throughout the FWC. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Numerical simulation of ground-water flow in lower Satus Creek Basin, Yakima Indian Reservation, Washington

USGS Publications Warehouse

Prych, E.A.

1983-01-01

A multilayer numerical model of steady-state ground-water flow in lower Satus Creek basin was constructed, calibrated using time-averaged data, and used to estimate the long-term effects of proposed irrigation-water management plans on ground-water levels in the area. Model computations showed that irrigation of new lands in the Satus uplands would raise ground-water levels in lower Satus Creek basin and thereby increase the size of the waterlogged areas. The model also demonstrated that pumping water from wells, reducing the amount of irrigation water used in the lowlands, and stopping leakage from Satus No. 2 and 3 Pump Canals were all effective methods to alleviate present waterlogging in some parts of the basin and to counteract some of the anticipated ground-water-level rises that would be caused by irrigating the uplands. The proposed changes in water use affected model-computed ground-water levels most in the eastern part of the basin between Satus No. 2 and No. 3 Pump Canals. The effects on ground-water levels in the western part of the basin between Satus Creek and Satus No. 2 Pump Canal were smaller. (USGS)

Ground-water conditions and studies in Georgia, 2001

USGS Publications Warehouse

Leeth, David C.; Clarke, John S.; Craigg, Steven D.; Wipperfurth, Caryl J.

2003-01-01

The U.S. Geological Survey (USGS) collects ground-water data and conducts studies to monitor hydrologic conditions, to better define ground-water resources, and address problems related to water supply and water quality. Data collected as part of ground-water studies include geologic, geophysical, hydraulic property, water level, and water quality. A ground-water-level network has been established throughout most of the State of Georgia, and ground-water-quality networks have been established in the cities of Albany, Savannah, and Brunswick and in Camden County, Georgia. Ground-water levels are monitored continuously in a network of wells completed in major aquifers of the State. This network includes 17 wells in the surficial aquifer, 12 wells in the upper and lower Brunswick aquifers, 73 wells in the Upper Floridan aquifer, 10 wells in the Lower Floridan aquifer and underlying units, 12 wells in the Claiborne aquifer, 1 well in the Gordon aquifer, 11 wells in the Clayton aquifer, 11 wells in the Cretaceous aquifer system, 2 wells in Paleozoic-rock aquifers, and 7 wells in crystalline-rock aquifers. In this report, data from these 156 wells were evaluated to determine whether mean-annual ground-water levels were within, below, or above the normal range during 2001, based on summary statistics for the period of record. Information from these summaries indicates that water levels during 2001 were below normal in almost all aquifers monitored, largely reflecting climatic effects from drought and pumping. In addition, water-level hydrographs for selected wells indicate that water levels have declined during the past 5 years (since 1997) in almost all aquifers monitored, with water levels in some wells falling below historical lows. In addition to continuous water-level data, periodic measurements taken in 52 wells in the Camden County-Charlton County area, and 65 wells in the city of Albany-Dougherty County area were used to construct potentiometric-surface maps for the Upper Floridan aquifer. Ground-water quality in the Upper Floridan aquifer is monitored in the cities of Albany, Savannah, and Brunswick and in Camden County; and monitored in the Lower Floridan aquifer in the Savannah and Brunswick areas. In the Albany area since 1998, nitrate concentrations in the Upper Floridan aquifer have increased in 4 of the 11 wells monitored, and in 1 well, concentrations were above the U.S. Environmental Protection Agency's (USEPA) 10 milligrams per liter (mg/L) drinking-water standard. In the Savannah area, chloride concentration in water from four wells in the Upper Floridan aquifer showed no appreciable change during 2001, remaining within the USEPA 250 mg/L drinking-water standard; in seven wells completed in the Lower Floridan aquifer and in underlying zones, the chloride concentration remained above the drinking-water standard, with one well showing an increase over previous years. In the Brunswick area, water samples from 66 wells completed in the Upper or Lower Floridan aquifers were collected during June 2001 and analyzed for chloride. A map showing chloride concentrations in the Upper Floridan aquifer during June 2001 indicates that concentrations remained above USEPA drinking-water standards across a 2-square-mile area. In the north Brunswick area, chloride concentrations in the Upper Floridan aquifer continued to increase, whereas in the south Brunswick area, concentrations continued to decrease. In the Camden County area, chloride concentrations in six wells completed in the Upper Floridan aquifer remained within drinking-water standards. With the exception of one well, concentrations remained the same and were below 40 mg/L. In one well, concentrations showed a sharp decline during 2001, but remained above 130 mg/L. Ongoing studies during 2001 include evaluation of agricultural chemicals in shallow ground water in southwestern Georgia; evaluation of saltwater intrusion and water-level and water-quality m

Land subsidence, groundwater levels, and geology in the Coachella Valley, California, 1993-2010

USGS Publications Warehouse

Sneed, Michelle; Brandt, Justin T.; Solt, Mike

2014-01-01

Land subsidence associated with groundwater-level declines has been investigated by the U.S. Geological Survey in the Coachella Valley, California, since 1996. Groundwater has been a major source of agricultural, municipal, and domestic supply in the valley since the early 1920s. Pumping of groundwater resulted in water-level declines as much as 15 meters (50 feet) through the late 1940s. In 1949, the importation of Colorado River water to the southern Coachella Valley began, resulting in a reduction in groundwater pumping and a recovery of water levels during the 1950s through the 1970s. Since the late 1970s, demand for water in the valley has exceeded deliveries of imported surface water, resulting in increased pumping and associated groundwater-level declines and, consequently, an increase in the potential for land subsidence caused by aquifer-system compaction. Global Positioning System (GPS) surveying and Interferometric Synthetic Aperture Radar (InSAR) methods were used to determine the location, extent, and magnitude of the vertical land-surface changes in the southern Coachella Valley during 1993–2010. The GPS measurements taken at 11 geodetic monuments in 1996 and in 2010 in the southern Coachella Valley indicated that the elevation of the land surface changed –136 to –23 millimeters (mm) ±54 mm (–0.45 to –0.08 feet (ft) ±0.18 ft) during the 14-year period. Changes at 6 of the 11 monuments exceeded the maximum expected uncertainty of ±54 mm (±0.18 ft) at the 95-percent confidence level, indicating that subsidence occurred at these monuments between June 1996 and August 2010. GPS measurements taken at 17 geodetic monuments in 2005 and 2010 indicated that the elevation of the land surface changed –256 to +16 mm ±28 mm (–0.84 to +0.05 ft ±0.09 ft) during the 5-year period. Changes at 5 of the 17 monuments exceeded the maximum expected uncertainty of ±28 mm (±0.09 ft) at the 95-percent confidence level, indicating that subsidence occurred at these monuments between August 2005 and August 2010. At each of these five monuments, subsidence rates were about the same between 2005 and 2010 as between 2000 and 2005. InSAR measurements taken between June 27, 1995, and September 19, 2010, indicated that the land surface subsided from about 220 to 600 mm (0.72 to 1.97 ft) in three areas of the Coachella Valley: near Palm Desert, Indian Wells, and La Quinta. In Palm Desert, the average subsidence rates increased from about 39 millimeters per year (mm/yr), or 0.13 foot per year (ft/yr), during 1995–2000 to about 45 mm/yr (0.15 ft/yr) during 2003–10. In Indian Wells, average subsidence rates for two subsidence maxima were fairly steady at about 34 and 26 mm/yr (0.11 and 0.09 ft/yr) during both periods; for the third maxima, average subsidence rates increased from about 14 to 19 mm/yr (0.05 to 0.06 ft/yr) from the first to the second period. In La Quinta, average subsidence rates for five selected locations ranged from about 17 to 37 mm/yr (0.06 to 0.12 ft/yr) during 1995–2000; three of the locations had similar rates during 2003–mid-2009, while the other two locations had increased subsidence rates. Decreased subsidence rates were calculated throughout the La Quinta subsidence area during mid-2009–10, however, and uplift was observed during 2010 near the southern extent of this area. Water-level measurements taken at wells near the subsiding monuments and in the three subsiding areas shown by InSAR generally indicated that the water levels fluctuated seasonally and declined annually from the early 1990s, or earlier, to 2010; some water levels in 2010 were at the lowest levels in their recorded histories. An exception to annually declining water levels in and near subsiding areas was observed beginning in mid-2009 in the La Quinta subsidence area, where recovering water levels coincided with increased recharge operations at the Thomas E. Levy Recharge Facility; decreased pumpage also could cause groundwater levels to recover. Subsidence concomitant with declining water levels and land-surface uplift concomitant with recovering water levels indicate that aquifer-system compaction could be causing subsidence. If the stresses imposed by the historically lowest water levels exceeded the preconsolidation stress, the aquifer-system compaction and associated land subsidence could be permanent.

Incorporating Sediment Compaction Into a Gravitationally Self-consistent Model for Global Sea-level Change

NASA Astrophysics Data System (ADS)

Ferrier, K.; Mitrovica, J. X.

2015-12-01

In sedimentary deltas and fans, sea-level changes are strongly modulated by the deposition and compaction of marine sediment. The deposition of sediment and incorporation of water into the sedimentary pore space reduces sea level by increasing the elevation of the seafloor, which reduces the thickness of sea-water above the bed. In a similar manner, the compaction of sediment and purging of water out of the sedimentary pore space increases sea level by reducing the elevation of the seafloor, which increases the thickness of sea water above the bed. Here we show how one can incorporate the effects of sediment deposition and compaction into the global, gravitationally self-consistent sea-level model of Dalca et al. (2013). Incorporating sediment compaction requires accounting for only one additional quantity that had not been accounted for in Dalca et al. (2013): the mean porosity in the sediment column. We provide a general analytic framework for global sea-level changes including sediment deposition and compaction, and we demonstrate how sea level responds to deposition and compaction under one simple parameterization for compaction. The compaction of sediment generates changes in sea level only by changing the elevation of the seafloor. That is, sediment compaction does not affect the mass load on the crust, and therefore does not generate perturbations in crustal elevation or the gravity field that would further perturb sea level. These results have implications for understanding sedimentary effects on sea-level changes and thus for disentangling the various drivers of sea-level change. ReferencesDalca A.V., Ferrier K.L., Mitrovica J.X., Perron J.T., Milne G.A., Creveling J.R., 2013. On postglacial sea level - III. Incorporating sediment redistribution. Geophysical Journal International, doi: 10.1093/gji/ggt089.

Nitrates in municipal drinking water and non-Hodgkin lymphoma: an ecological cancer case-control study in Taiwan.

PubMed

Chang, Chih-Ching; Tsai, Shang-Shyue; Wu, Trong-Neng; Yang, Chun-Yuh

2010-01-01

The relationship between nitrate levels in drinking water and increased risk of non-Hodgkin lymphoma (NHL) development has been inconclusive. A matched cancer case-control and a nitrate ecology study was used to investigate the association between mortality attributed to NHL and nitrate exposure from Taiwan's drinking water. All deaths due to NHL in Taiwan residents from 2000 through 2006 were obtained from the Bureau of Vital Statistics of the Taiwan Provincial Department of Health. Controls were deaths from other causes and were pair-matched to the cases by gender, year of birth, and year of death. Each matched control was selected randomly from the set of possible controls for each case. Data on nitrate-nitrogen (NO(3)-N) levels of drinking water throughout Taiwan were collected from the Taiwan Water Supply Corporation (TWSC). The municipality of residence for cancer cases and controls was presumed to be the source of the subject's nitrate exposure via drinking water. The adjusted odds ratios (OR) for NHL death for those with high nitrate levels in their drinking water, as compared to the lowest tertile, were 1.02 (0.87-1.2) and 1.05 (0.89-1.24), respectively. The results of the present study show that there was no statistically significant association between nitrates in drinking water at levels in this investigation and increased risk of death attributed to NHL.

Optimization Program for Drinking Water Systems

EPA Pesticide Factsheets

The Area-Wide Optimization Program (AWOP) provides tools and approaches for drinking water systems to meet water quality optimization goals and provide an increased – and sustainable – level of public health protection to their consumers.

Hydrogeology and Simulation of Groundwater Flow in the Plymouth-Carver-Kingston-Duxbury Aquifer System, Southeastern Massachusetts

USGS Publications Warehouse

Masterson, John P.; Carlson, Carl S.; Walter, Donald A.; Other contributing authors: Bent, Gardner C.; Massey, Andrew J.

2009-01-01

The glacial sediments that underlie the Plymouth-Carver-Kingston-Duxbury area of southeastern Massachusetts compose an important aquifer system that is the primary source of water for a region undergoing rapid development. Population increases and land-use changes in this area has led to two primary environmental effects that relate directly to groundwater resources: (1) increases in pumping that can adversely affect environmentally sensitive groundwater-fed surface waters, such as ponds, streams, and wetlands; and (2) adverse effects of land use on the quality of water in the aquifer. In response to these concerns, the U.S. Geological Survey, in cooperation with the Massachusetts Department of Environmental Protection, began an investigation in 2005 to improve the understanding of the hydrogeology in the area and to assess the effects of changing pumping and recharge conditions on groundwater flow in the Plymouth-Carver-Kingston-Duxbury aquifer system. A numerical flow model was developed based on the USGS computer program MODFLOW-2000 to assist in the analysis of groundwater flow. Model simulations were used to determine water budgets, flow directions, and the sources of water to pumping wells, ponds, streams, and coastal areas. Model-calculated water budgets indicate that approximately 298 million gallons per day (Mgal/d) of water recharges the Plymouth-Carver-Kingston-Duxbury aquifer system. Most of this water (about 70 percent) moves through the aquifer, discharges to streams, and then reaches the coast as surface-water discharge. Of the remaining 30 percent of flow, about 25 percent of the water that enters the aquifer as recharge discharges directly to coastal areas and 5 percent discharges to pumping wells. Groundwater withdrawals are anticipated to increase from the current (2005) rate of about 14 Mgal/d to about 21 Mgal/d by 2030. Pumping from large-capacity production wells decreases water levels and increases the potential for effects on surface-water bodies, which are affected by pumping and wastewater disposal locations and rates. Pumping wells that are upgradient of surface-water bodies potentially capture water that would otherwise discharge to these surface-water bodies, thereby reducing streamflow and pond levels. The areas most affected by proposed increases in groundwater withdrawals are in the Towns of Plymouth and Wareham where more than half of the proposed increase in pumping will occur. In response to an increase of about 7 Mgal/d of pumping, groundwater discharge to streams is reduced by about 6 cubic feet per second (ft3/s) (about 4 Mgal/d) from a total of about 325 ft3/s. Reduction in streamflow is moderated by an increase of artificial recharge from wastewater returned to the aquifer by onsite domestic septic systems and centralized wastewater treatment facilities. It is anticipated that about 3 Mgal/d of the 7 Mgal/d of increase in pumped water will be returned to the aquifer as wastewater by 2030. Currently (2005) about 3 percent of groundwater discharge to streams is from wastewater return flow to the aquifer during average conditions. During drought conditions, the component of streamflow augmented by wastewater return flow doubles as wastewater recharge remains constant and aquifer recharge rates decrease. Wastewater return flow, whether as direct groundwater discharge to streams or as an additional source of aquifer recharge, increases the height of the water table near streams, thereby moderating the effects of increased groundwater withdrawals on streamflow. An analysis of a simulated drought similar to the 1960s drought of record indicates that the presence of streams moderates the effects on water levels of reduced aquifer recharge. The area where water-table altitudes were least affected by drought was in the Weweantic River watershed in the Town of Carver. Water levels decreased by less than 2 feet from current average conditions compared to decreases of greater than 5

Regional-scale impact of storm surges on groundwaters of Texas, Florida and Puerto Rico after 2017 hurricanes Harvey, Irma, Jose, Maria

NASA Astrophysics Data System (ADS)

Sellier, W. H.; Dürr, H. H.

2017-12-01

Hurricanes and related storm surges have devastating effects on near-shore infrastructure and above-ground installations. They also heavily impact groundwater resources, with potentially millions of people dependant on these resources as a freshwater source. Destructions of casings and direct incursions of saline and/or polluted waters have been widely observed. It is uncertain how extensive the effects are on underground water systems, especially in limestone karst areas such as Florida and Puerto Rico. Here, we report regional-scale water level changes in groundwater systems of Texas, Florida and Puerto Rico for the 2017 Hurricanes Harvey, Irma, Jose and Maria. We collected regional scale data from the USGS Waterdata portal. Puerto Rico shows the strongest increase in groundwater levels in wells during Hurricane Maria, with less reaction for the preceding storms Irma and Jose. Increases in water levels range from 0.5 to 11m, with maximum storm surges in Puerto Rico around 3m. These wells are located throughout Puerto Rico, on the coast and inland. In Florida, most wells that show a response during Hurricane Irma are located in the Miami region. Wells located on the west coast show smaller responses with the exception of one well located directly on Hurricane Irma's track. These wells show an increase of 0.2 to 1.7m. In Texas, wells located in proximity to Hurricane Harvey's track show an increase in water level. The effect of groundwater level increases is not limited to the Texas coast, but inland as well. An increase between 0.03 and 2.9m is seen. Storm surges for both Florida and Texas have ranged from 1.8-3.7m maximum. We discuss the findings in the context of local and regional geology and hydrogeology (presence of connected aquifer systems, faulting, presence of carbonate/karst systems etc.).

Free cortisol and salivary alpha-amylase levels during a six-hour-water immersion in healthy young men

NASA Astrophysics Data System (ADS)

Rohleder, N.; Wirth, D.; Fraßl, W.; Kowoll, R.; Schlemmer, M.; Vogler, S.; Kirsch, K. A.; Kirschbaum, C.; Gunga, H.-C.

2005-08-01

Limited data are available on the response of stress systems to microgravity. Increased activity of stress systems is reported during space flight, but unchanged or decreased activity during simulated microgravity. We here investigated the impact of head-out water immersion on the activity of the hypothalamus-pituitary-adrenal (HPA) axis and the sympathetic-adrenal-medullary (SAM) system.Eight healthy young men were exposed to a six-hour water immersion in a thermo neutral bath and a control condition. Saliva samples were taken before, during, and after interventions to assess cortisol as an index for HPA axis activity, and salivary α-amylase as an index for SAM system activity.Cortisol levels uniformly decreased during both conditions. Amylase levels increased during both conditions, but were significantly lower during the first half of water immersion compared to the control condition.In conclusion, the HPA axis is not influenced by simulated microgravity, while SAM system activity shows initial decreases during water immersion.

Quality of water from shallow wells in the rice-growing area in southwestern Louisiana, 1999 through 2001

USGS Publications Warehouse

Tollett, Roland W.; Fendick, Robert B.

2004-01-01

In 1999-2001, the U.S. Geological Survey installed and sampled 27 shallow wells in the rice-growing area in southwestern Louisiana as part of the Acadian-Pontchartrain Study Unit of the National Water-Quality Assessment Program. The purpose of this report is to describe the waulity of water from shallow wells in the rice-growing area and to relate that water quality to natural and anthropogenic activities, particularly rice agriculture. Ground-water samples were analyzed for general ground-water properties and about 150 water-quality constituents, including major inorganic ions, trace elements, nutrients, dissolved organic carbon (DOC), pesticides, radon, chloroflourocarbons, and selected stable isotopes. Dissolved solids concentrations for 17 wells exceeded the U.S. Environmental Protection Agency secondary minimum containment level of 500 milligrams per liter (mg/L) for drinking water. Concentrations for major pesticides generally were less than the maximum contaminant levels for drinking water. Two major inorganic ions, sulfate and chloride, and two trace elements, iron and manganese, had concentrations that were greater than the secondary maximum containment levels. Three nutrient concentrations were greater than 2 mg/L, a level that might indicate contamination from human activities, and one nutrient concentration (that for nitrite plus nitrite as nitrogen) was greater than the maximum contaminant level of 10 mg/L for drinking water. The median concentration for DOC was 0.5 mg/L, indicating naturally-occurring DOC conditions in the study area. Thirteen pesticides and 7 pesticide degradation products were detected in 14 of the 27 wells sampled. Bentazon, 2, 4-D, and molinate (three rice herbicides) were detected in water from four, one, and one wells, respectively, and malathion (a rice insecticide) was deteced in water fromone well. Low-level concentrations and few detections of nutrients and pesticides indicated that ground-water quality was affected slightly by anthropogenic activities. Quality-control samples, including field blanks, replicates, and spikes, indicated no bias in ground-water data from collection on analysis. Radon concentrations for 22 of the 24 wells sampled wer at or greater than the U.S. Environmental Protection Agency proposed maximum contaminant level of 300 picocuries per liter. Chlorofluorocarbon concentrations in selected wells indicated the apparent ages of the ground water varied with depth water level and ranged from about 17 to 49 years. The stable isotopes of hydrogen and oxygen in water molecules indicated the origin of ground water in the study area was rainwater that originated near the study area and that few geochemical or physical processes influenced the stable isotopic composition of the shallow ground water. The Spearman rank correlation was used to detemrine whther significant correlations existed between physical properties, selected chemical constituents, the number of pesticides detected, and the apparent age of water. The depth to ground water was positively correlated to the well depth and inversely correlated to dissolved solids and other constituents, such as radon, indicating the ground water was under unconfined or semiconfined conditions and more dilute with increasing depth. As the depth to ground water increased, the concentrations of dissolved solids and other constituents decreased, possibly because the deeper sands had a greater transmittal of ground water, which, over time, would flush out, or dilute, the concentrations of dissolved solids in the natural sediments. The apparent age of water was correlated inversely with nitrite plus nitrite concentration, indicating that as apparent age increased, the nitrite plus nitrite concentration decreased. No significant correlations existed between the number of pesticides detected and any of the physical or chemica

The influence of sea-level rise on fringing reef sediment dynamics: field observations and numerical modeling

USGS Publications Warehouse

Storlazzi, Curt D.; Field, Michael E.; Elias, Edwin; Presto, M. Katherine

2011-01-01

While most climate projections suggest that sea level may rise on the order of 0.5-1.0 m by 2100, it is not clear how fluid flow and sediment transport on fringing reefs might change in response to this rapid sea-level rise. Field observations and numerical modeling suggest that an increase in water depth on the order of 0.5-1.0 m on a fringing reef flat would result in larger significant wave heights and wave-driven shear stresses, which, in turn, would result in an increase in both the size and quantity of sediment that can be resuspended from the seabed or eroded from coastal plain deposits. Greater wave- and wind-driven currents would develop on the reef flat with increasing water depth, increasing the offshore flux of water and sediment from the inner reef flat to the outer reef flat and fore reef where coral growth is typically greatest.

Review of Knowledge on the Occurrence, Chemical Composition, and Potential Use for Desalination of Saline Ground Water in Arizona, New Mexico, and Texas with a Discussion of Potential Future Study Needs

USGS Publications Warehouse

Huff, G.F.

2004-01-01

Increasing demand on the limited supplies of freshwater in the desert Southwest, as well as other parts of the United States, has increased the level of interest in saline-water resources. Saline ground water has long been recognized as a potentially important contributor to water supply in the Southwest, as demonstrated by the number of hydrologic, geologic, and engineering studies on the distribution of saline water and the feasibility of desalination. Potential future study needs include investigating and documenting the three-dimensional distribution of salinity and chemical composition of saline-water resources and the hydraulic properties of aquifers containing these saline-water resources, assessing the chemical suitability of saline water for use with existing and anticipated desalination technologies, simulating the effect of withdrawal of saline ground water on water levels and water composition in saline and adjoining or overlying freshwater aquifers, and determining the suitability of target geologic formations for injection of desalination-generated waste.

Effect of sunlight exposure on the release of intentionally and/or non-intentionally added substances from polyethylene terephthalate (PET) bottles into water: chemical analysis and in vitro toxicity.

PubMed

Bach, Cristina; Dauchy, Xavier; Severin, Isabelle; Munoz, Jean-François; Etienne, Serge; Chagnon, Marie-Christine

2014-11-01

The effect of sunlight exposure on chemical migration into PET-bottled waters was investigated. Bottled waters were exposed to natural sunlight for 2, 6 and 10 days. Migration was dependent on the type of water. Formaldehyde, acetaldehyde and Sb migration increased with sunlight exposure in ultrapure water. In carbonated waters, carbon dioxide promoted migration and only formaldehyde increased slightly due to sunlight. Since no aldehydes were detected in non-carbonated waters, we conclude that sunlight exposure has no effect. Concerning Sb, its migration levels were higher in carbonated waters. No unpredictable NIAS were identified in PET-bottled water extracts. Cyto-genotoxicity (Ames and micronucleus assays) and potential endocrine disruption effects (transcriptional-reporter gene assays) were checked in bottled water extracts using bacteria (Salmonella typhimurium) and human cell lines (HepG2 and MDA-MB453-kb2). PET-bottled water extracts did not induce any toxic effects (cyto-genotoxicity, estrogenic or anti-androgenic activity) in vitro at relevant consumer-exposure levels. Copyright © 2014 Elsevier Ltd. All rights reserved.

Ground-Water Recharge in Minnesota

USGS Publications Warehouse

Delin, G.N.; Falteisek, J.D.

2007-01-01

'Ground-water recharge' broadly describes the addition of water to the ground-water system. Most water recharging the ground-water system moves relatively rapidly to surface-water bodies and sustains streamflow, lake levels, and wetlands. Over the long term, recharge is generally balanced by discharge to surface waters, to plants, and to deeper parts of the ground-water system. However, this balance can be altered locally as a result of pumping, impervious surfaces, land use, or climate changes that could result in increased or decreased recharge. * Recharge rates to unconfined aquifers in Minnesota typically are about 20-25 percent of precipitation. * Ground-water recharge is least (0-2 inches per year) in the western and northwestern parts of the State and increases to greater than 6 inches per year in the central and eastern parts of the State. * Water-level measurement frequency is important in estimating recharge. Measurements made less frequently than about once per week resulted in as much as a 48 percent underestimation of recharge compared with estimates based on an hourly measurement frequency. * High-quality, long-term, continuous hydrologic and climatic data are important in estimating recharge rates.

Examination and characterization of distribution system biofilms.

PubMed Central

LeChevallier, M W; Babcock, T M; Lee, R G

1987-01-01

Investigations concerning the role of distribution system biofilms on water quality were conducted at a drinking water utility in New Jersey. The utility experienced long-term bacteriological problems in the distribution system, while treatment plant effluents were uniformly negative for coliform bacteria. Results of a monitoring program showed increased coliform levels as the water moved from the treatment plant through the distribution system. Increased coliform densities could not be accounted for by growth of the cells in the water column alone. Identification of coliform bacteria showed that species diversity increased as water flowed through the study area. All materials in the distribution system had high densities of heterotrophic plate count bacteria, while high levels of coliforms were detected only in iron tubercles. Coliform bacteria with the same biochemical profile were found both in distribution system biofilms and in the water column. Assimilable organic carbon determinations showed that carbon levels declined as water flowed through the study area. Maintenance of a 1.0-mg/liter free chlorine residual was insufficient to control coliform occurrences. Flushing and pigging the study area was not an effective control for coliform occurrences in that section. Because coliform bacteria growing in distribution system biofilms may mask the presence of indicator organisms resulting from a true breakdown of treatment barriers, the report recommends that efforts continue to find methods to control growth of coliform bacteria in pipeline biofilms. Images PMID:3435140

Compilation of geohydrologic data collected as part of the areal appraisal of ground-water resources near Branson, Missouri

USGS Publications Warehouse

Imes, J.L.

1989-01-01

A rapidly developing retirement community and tourist industry in the Branson, Missouri area has created an increased demand for potable water, especially in the summer months. The rapid pace of residential and business expansion has created concerns regarding the future groundwater availability and quality. Water levels measured in the Ozark aquifer during the summer of 1988 and March 1989 show water levels increasing in 22 wells, decreasing in 2 wells, and remaining the same in 1 well. The water level increases ranged from 1 to 111 ft. These measurements and similar measurements during the summer of 1989 will be used to calibrate a three-dimensional model of groundwater flow in the Branson area and estimate the long-term effect of large groundwater withdrawals during the summer tourist season. A reconnaissance of water quality in 34 wells that are open to the Ozark aquifer shows specific conductance ranging from 347 to 841 microsiemens/cm at 25 C and no fecal coliform bacteria present in any well. Chloride and nitrate concentrations in all wells were well below the Missouri Department of Natural Resources recommended maximum concentrations of 250 mg/L and 10 mg/L, respectively. Analysis of 5 water samples for 33 volatile organic compounds failed to detect any concentrations in excess of the detection limits. (USGS)

Hydrology and water quality of lakes and streams in Orange County, Florida

USGS Publications Warehouse

German, Edward R.; Adamski, James C.

2005-01-01

Orange County, Florida, is continuing to experience a large growth in population. In 1920, the population of Orange County was less than 20,000; in 2000, the population was about 896,000. The amount of urban area around Orlando has increased considerably, especially in the northwest part of the County. The eastern one-third of the County, however, had relatively little increase in urbanization from 1977-97. The increase of population, tourism, and industry in Orange County and nearby areas changed land use; land that was once agricultural has become urban, industrial, and major recreation areas. These changes could impact surface-water resources that are important for wildlife habitat, for esthetic reasons, and potentially for public supply. Streamflow characteristics and water quality could be affected in various ways. As a result of changing land use, changes in the hydrology and water quality of Orange County's lakes and streams could occur. Median runoff in 10 selected Orange County streams ranges from about 20 inches per year (in/yr) in the Wekiva River to about 1.1 in/yr in Cypress Creek. The runoff for the Wekiva River is significantly higher than other river basins because of the relatively constant spring discharge that sustains streamflow, even during drought conditions. The low runoff for the Cypress Creek basin results from a lack of sustained inflow from ground water and a relatively large area of lakes within the drainage basin. Streamflow characteristics for 13 stations were computed on an annual basis and examined for temporal trends. Results of the trend testing indicate changes in annual mean streamflow, 1-day high streamflow, or 7-day low streamflow at 8 of the 13 stations. However, changes in 7-day low streamflow are more common than changes in annual mean or 1-day high streamflow. There is probably no single reason for the changes in 7-day low streamflows, and for most streams, it is difficult to determine definite reasons for the flow increases. Low flows in the Econlockhatchee River at Chuluota have increased because of discharge of treated wastewater since 1982. However, trends in increasing 7-day low streamflow are evident before 1982, which cannot be attributed to wastewater discharge. Some of the increases in 7-day low flows may be related to drainage changes resulting from increased development in Orange County. Development for most purposes, including those as diverse as cattle grazing and residential construction, may involve modification of surface drainage through stream channelization and construction of canals. These changes in land drainage can lower the water table, resulting in reductions of regional evapotranspiration rates and increased streamflow. Another possible cause of increasing low flows in streams is use of water from the Floridan aquifer system for irrigation. Runoff of irrigation water or increased seepage from irrigated areas to streams could increase base streamflow compared to natural conditions. Water-level data were analyzed to determine temporal trends from 83 lakes that had more than 15 years of record. There were significant temporal trends in 33 of the 83 lakes (40 percent) over the entire period of record. Of these 33 lakes, 14 had increasing water levels and 19 lakes had decreasing water levels. The downward trends in long-term lake levels could in part be due to high rainfall accumulation in 1960-1961, which included precipitation from Hurricane Donna (September 1960). The high rainfall resulted in historical high-water levels in many lakes in 1960 or 1961. A large range of water-quality conditions exists in lakes and streams of Orange County (2000-01). Specific conductance in lake samples ranged from 57 to 1,185 microsiemens per centimeter. Values of pH ranged from 3.2 to 8.7 in stream samples and 4.6 to 9.6 in lake samples. Total nitrogen concentrations ranged from less than 0.2 to 7.1 milligrams per liter (mg/L) as nitrogen in stream samples, and

Photosynthesis, Transpiration, Leaf Temperature, and Stomatal Activity of Cotton Plants under Varying Water Potentials

PubMed Central

Pallas, J. E.; Michel, B. E.; Harris, D. G.

1967-01-01

Cotton plants, Gossypium hirsutum L. were grown in a growth room under incident radiation levels of 65, 35, and 17 Langleys per hour to determine the effects of vapor pressure deficits (VPD's) of 2, 9, and 17 mm Hg at high soil water potential, and the effects of decreasing soil water potential and reirrigation on transpiration, leaf temperature, stomatal activity, photosynthesis, and respiration at a VPD of 9 mm Hg. Transpiration was positively correlated with radiation level, air VPD and soil water potential. Reirrigation following stress led to slow recovery, which may be related to root damage occurring during stress. Leaf water potential decreased with, but not as fast as, soil water potential. Leaf temperature was usually positively correlated with light intensity and negatively correlated with transpiration, air VPD, and soil water. At high soil water, leaf temperatures ranged from a fraction of 1 to a few degrees above ambient, except at medium and low light and a VPD of 19 mm Hg when they were slightly below ambient, probably because of increased transpirational cooling. During low soil water leaf temperatures as high as 3.4° above ambient were recorded. Reirrigation reduced leaf temperature before appreciably increasing transpiration. The upper leaf surface tended to be warmer than the lower at the beginning of the day and when soil water was adequate; otherwise there was little difference or the lower surface was warmer. This pattern seemed to reflect transpiration cooling and leaf position effects. Although stomata were more numerous in the lower than the upper epidermis, most of the time a greater percentage of the upper were open. With sufficient soil water present, stomata opened with light and closed with darkness. Fewer stomata opened under low than high light intensity and under even moderate, as compared with high soil water. It required several days following reirrigation for stomata to regain original activity levels. Apparent photosynthesis of cotton leaves occasionally oscillated with variable amplitude and frequency. When soil water was adequate, photosynthesis was nearly proportional to light intensity, with some indication of higher rates at higher VPD's. As soil water decreased, photosynthesis first increased and then markedly decreased. Following reirrigation, photosynthesis rapidly recovered. Respiration was slowed moderately by decreasing soil water but increased before watering. Respiration slowed with increasing leaf age only on leaves that were previously under high light intensity. PMID:16656488

Optimization of ground-water withdrawal in the lower Fox River communities, Wisconsin

USGS Publications Warehouse

Walker, J.F.; Saad, D.A.; Krohelski, J.T.

1998-01-01

Pumping from closely spaced wells in the Central Brown County area and the Fox Cities area near the north shore of Lake Winnebago has resulted in the formation of deep cones of depression in the vicinity of the two pumping centers. Water-level measurements indicate there has been a steady decline in water levels in the vicinity of these two pumping centers for the past 50 years. This report describes the use of ground-water optimization modeling to efficiently allocate the ground-water resources in the Lower Fox River Valley. A 3-dimensional ground-water flow model was used along with optimization techniques to determine the optimal withdrawal rates for a variety of management alternatives. The simulations were conducted separately for the Central Brown County area and the Fox Cities area. For all simulations, the objective of the optimization was to maximize total ground-water withdrawals. The results indicate that ground water can supply nearly all of the projected 2030 demand for Central Brown County municipalities if all of the wells are managed (including the city of Green Bay), 8 new wells are installed, and the water-levels are allowed to decline to 100 ft below the bottom of the confining unit. Ground water can supply nearly all of the projected 2030 demand for the Fox Cities if the municipalities in Central Brown County convert to surface water; if Central Brown County municipalities follow the optimized strategy described above, there will be a considerable shortfall of available ground water for the Fox Cities communities. Relaxing the water-level constraint in a few wells, however, would likely result in increased availability of water. In all cases examined, optimization alternatives result in a rebound of the steady-state water levels due to projected 2030 withdrawal rates to levels at or near the bottom of the confining unit, resulting in increased well capacity. Because the simulations are steady-state, if all of the conditions of the model remain the same these withdrawal rates would be sustainable in perpetuity.

Estimated 2012 groundwater potentiometric surface and drawdown from predevelopment to 2012 in the Santa Fe Group aquifer system in the Albuquerque metropolitan area, central New Mexico

USGS Publications Warehouse

Powell, Rachel I.; McKean, Sarah E.

2014-01-01

Historically, the water-supply requirements of the Albuquerque metropolitan area of central New Mexico were met almost exclusively by groundwater withdrawal from the Santa Fe Group aquifer system. In response to water-level declines, the Albuquerque Bernalillo County Water Utility Authority (ABCWUA) began diverting water from the San Juan-Chama Drinking Water Project in December 2008 to reduce the use of groundwater to meet municipal demand. Modifications in the demand for water and the source of the supply of water for the Albuquerque metropolitan area have resulted in a variable response in the potentiometric surface of the production zone (the interval of the aquifer, from within about 200 feet below the water table to 900 feet or more, in which supply wells generally are screened) of the Santa Fe Group aquifer system. Analysis of the magnitude and spatial distribution of water-level change can help improve the understanding of how the groundwater system responds to withdrawals and variations in the management of the water supply and can support water-management agencies’ efforts to minimize future water-level declines and improve sustainability. The U.S. Geological Survey (USGS), in cooperation with the ABCWUA, has developed an estimate of the 2012 potentiometric surface of the production zone of the Santa Fe Group aquifer system in the Albuquerque metropolitan area. This potentiometric surface is the latest in a series of reports depicting the potentiometric surface of the area. This report presents the estimated potentiometric surface during winter (from December to March) of water year 2012 and the estimated changes in potentiometric surface between predevelopment (pre-1961) and water year 2012 for the production zone of the Santa Fe Group aquifer system in the Albuquerque metropolitan area. Hydrographs from selected piezometers are included to provide details of historical water-level changes. In general, water-level measurements used for this report were collected in small-diameter observation wells screened over short intervals near the middle of the production zone and were considered to best represent the potentiometric head in the production zone. The water-level measurements were collected by various local and Federal agencies. The water year 2012 potentiometric surface map was created in a geographic information system, and the change in water-level altitude from predevelopment to water year 2012 was calculated. The 2012 potentiometric surface indicates that the general direction of groundwater flow is from the Rio Grande towards clusters of supply wells in the east, north, and west. Water-level changes from predevelopment to 2012 were variable across the Albuquerque metropolitan area. Estimated drawdown from 2008 was spatially variable across the Albuquerque metropolitan area. Hydrographs from piezometers on the east side of the river indicate an increase in the annual highest water-level measurement from 2008 to 2012. Hydrographs from piezometers in the northwest part of the study area indicate either steady decline of the water-level altitude over the period of record or recently variable trends in which water-level altitudes increased for a number of years but have declined since water year 2012.

Water quality following extensive beetle-induced tree mortality: Interplay of aromatic carbon loading, disinfection byproducts, and hydrologic drivers.

PubMed

Brouillard, Brent M; Dickenson, Eric R V; Mikkelson, Kristin M; Sharp, Jonathan O

2016-12-01

The recent bark beetle epidemic across western North America may impact water quality as a result of elevated organic carbon release and hydrologic shifts associated with extensive tree dieback. Analysis of quarterly municipal monitoring data from 2004 to 2014 with discretization of six water treatment facilities in the Rocky Mountains by extent of beetle impact revealed a significant increasing trend in total organic carbon (TOC) and total trihalomethane (TTHM) production within high (≳50% areal infestation) beetle-impacted watersheds while no or insignificant trends were found in watersheds with lower impact levels. Alarmingly, the TTHM concentration trend in the high impact sites exceeded regulatory maximum contaminant levels during the most recent two years of analysis (2013-14). To evaluate seasonal differences, explore the interplay of water quality and hydrologic processes, and eliminate variability associated with municipal reporting, these treatment facilities were targeted for more detailed surface water sampling and characterization. Surface water samples collected from high impact watersheds exhibited significantly higher TOC, aromatic signatures, and disinfection byproduct (DBP) formation potential than watersheds with lower infestation levels. Spectroscopic analyses of surface water samples indicated that these heightened DBP precursor levels are a function of both elevated TOC loading and increased aromatic character. This association was heightened during precipitation and runoff events in high impact sites, supporting the hypothesis that altered hydrologic flow paths resulting from tree mortality mobilize organic carbon and elevate DBP formation potential for several months after runoff ceases. The historical trends found here likely underestimate the full extent of TTHM shifts due to monitoring biases with the extended seasonal release of DBP precursors increasing the potential for human exposure. Collectively, our analysis suggests that while water quality impacts continue to rise nearly one decade after infestation, significant increases in TOC mobilization and DBP precursors are limited to watersheds that experience extensive tree mortality. Copyright © 2016 Elsevier B.V. All rights reserved.

Sinkhole flooding in Murfreesboro, Rutherford County, Tennessee, 2001-02

USGS Publications Warehouse

Bradley, Michael W.; Hileman, Gregg Edward

2006-01-01

The U.S. Geological Survey, in cooperation with the City of Murfreesboro, Tennessee, conducted an investigation from January 2001 through April 2002 to delineate sinkholes and sinkhole watersheds in the Murfreesboro area and to characterize the hydrologic response of sinkholes to major rainfall events. Terrain analysis was used to define sinkholes and delineate the sinkhole drainage areas. Flooding in 78 sinkholes in three focus areas was identified and tracked using aerial photography following three major storms in February 2001, January 2002, and March 2002. The three focus areas are located to the east, north, and northwest of Murfreesboro and are underlain primarily by the Ridley Limestone with some outcrops of the underlying Pierce Limestone. The observed sinkhole flooding is controlled by water inflow, water outflow, and the degree of the hydraulic connection (connectivity) to a ground-water conduit system. The observed sinkholes in the focus areas are grouped into three categories based on the sinkhole morphology and the connectivity to the ground-water system as indicated by their response to flooding. The three types of sinkholes described for these focus areas are pan sinkholes with low connectivity, deep sinkholes with high connectivity, and deep sinkholes with low connectivity to the ground-water conduit system. Shallow, broad pan sinkholes flood as water inflow from a storm inundates the depression at land surface. Water overflow from one pan sinkhole can flow downgradient and become inflow to a sinkhole at a lower altitude. Land-surface modifications that direct more water into a pan sinkhole could increase peak-flood altitudes and extend flood durations. Land-surface modifications that increase the outflow by overland drainage could decrease the flood durations. Road construction or alterations that reduce flow within or between pan sinkholes could result in increased flood durations. Flood levels and durations in the deeper sinkholes observed in the three focus areas are primarily affected by the connectivity with the ground-water conduit system. Deep sinkholes with a relatively high connectivity to the ground-water system fill quickly after a storm, and drain rapidly after the storm ends, and water levels decline as much as 3 to 5 feet per day in the first 2 to 3 days after a major storm. These sinkholes store the initial floodwater and then rapidly transmit water to the ground-water conduit system (high outflow). Land-surface changes that direct more water into the sinkhole may increase the flood peaks, but may not have a substantial effect on the flood durations. Deep sinkholes that have low connectivity to the ground-water conduit system may have a delayed peak water level and may drain slowly, only about 2 to 3 feet in 10 days. Outflow from these sinkholes is limited or restricted by low connectivity to the ground-water conduit system. Land-surface alterations that increase the inflow to the sinkholes can result in high flood levels or increased flood durations.

The synthesis of corncobs (zea mays) active charcoal and water hyacinth (eichornia crassipes) adsorbent to adsorb Pb(II) with it’s analysis using solid-phase spectrophotometry (sps)

NASA Astrophysics Data System (ADS)

Saputro, S.; Masykuri, M.; Mahardiani, L.; Kurniastuti, D.

2018-03-01

This research aim to examine the effect of the combination between corncobs and water hyacinth to adsorb lead (II), the most effective combination have determined by compared the ratio of corncobs adsorbent and water hyacinth to the increasing adsorption of the Pb(II), prove the effectiveness of the solid-phase spectrophotometry (sps) to determine the levels of Pb(II) as the result of the corncobs active charcoal adsorption and water hyacinth in the level of µg/L. The research method used is experimental method. The data collecting technique is carried out by several stages, which are carbonization using muffle furnace at a temperature of 350°C for 1.5 hours, activation of the corncobs charcoal and water hyacinth using HCl 1M and HCl 5M activator, contacting the adsorbent of corncobs active charcoal and water hyacinth with liquid waste simulation of Pb(II) using variation of corncobns and water hyacinth, 1:0; 0:1; 1:1; 2:1; 1:2, analysis of Pb(II) using an sps, characterization of corncobs active charcoal adsorbent and water hyacinth using FTIR. Research results show that the combined effect of activated charcoal corncobs and water hyacinth can increase the ability of the adsorbent to absorb Pb(II), the optimum adsorbent mass ratio of 1:1 with the absorption level of 90.33%, SPS is an effective method to analyze the decreasing level of Pb(II) as the adsorbtion result of the corncobs active charcoal and water hyacinth in the level of µg/L, with the limit of detection (LOD) of 0.06 µg/L.

Climate-water quality relationships in Texas reservoirs

USGS Publications Warehouse

Gelca, Rodica; Hayhoe, Katharine; Scott-Fleming, Ian; Crow, Caleb; Dawson, D.; Patino, Reynaldo

2015-01-01

Water temperature, dissolved oxygen, and concentrations of salts in surface water bodies can be affected by the natural environment, local human activities such as surface and ground water withdrawals, land use, and energy extraction, and variability and long-term trends in atmospheric conditions including temperature and precipitation. Here, we quantify the relationship between 121 indicators of mean and extreme temperature and precipitation and 24 water quality parameters in 57 Texas reservoirs using observational data records covering the period 1960 to 2010. We find that water temperature, dissolved oxygen, pH, specific conductance, chloride, sulfate, and phosphorus all show consistent correlations with atmospheric predictors, including high and low temperature extremes, dry days, heavy precipitation events, and mean temperature and precipitation over time scales ranging from one week to two years. Based on this analysis and published future projections for this region, we expect climate change to increase water temperatures, decrease dissolved oxygen levels, decrease pH, increase specific conductance, and increase levels of sulfate, chloride in Texas reservoirs. Over decadal time scales, this may affect aquatic ecosystems in the reservoirs, including altering the risk of conditions conducive to algae occurrence, as well as affecting the quality of water available for human consumption and recreation.

Catastrophic subsidence: An environmental hazard, shelby county, Alabama

NASA Astrophysics Data System (ADS)

Lamoreaux, Philip E.; Newton, J. G.

1986-03-01

Induced sinkholes (catastrophic subsidence) are those caused or accelerated by human activities These sinkholes commonly result from a water level decline due to pumpage Construction activities in a cone of depression greatly increases the likelihood of sinkhole occurrence Almost all occur where cavities develop in unconsolidated deposits overlying solution openings in carbonate rocks. Triggering mechanisms resulting from water level declines are (1) loss of buoyant support of the water, (2) increased gradient and water velocity, (3) water-level fluctuations, and (4) induced recharge Construction activities triggering sinkhole development include ditching, removing overburden, drilling, movement of heavy equipment, blasting and the diversion and impoundment of drainage Triggering mechanisms include piping, saturation, and loading Induced sinkholes resulting from human water development/management activities are most predictable in a youthful karst area impacted by groundwater withdrawals Shape, depth, and timing of catastrophic subsidence can be predicted in general terms Remote sensing techniques are used in prediction of locations of catastrophic subsidence. This provides a basis for design and relocation of structures such as a gas pipeline, dam, or building Utilization of techniques and a case history of the relocation of a pipeline are described

Seasonal changes in antifreeze protein gene transcription and water content of beetle Microdera punctipennis (Coleoptera, Tenebrionidae) from Gurbantonggut desert in Central Asia.

PubMed

Hou, F; Ma, J; Liu, X; Wang, Y; Liu, X N; Zhang, F C

2010-01-01

Desert beetle Microdera punctipennis (Coleoptera: Tenebriondae) is a special species in Gurbantonggut Desert in Central Asia. To investigate the possible strategy it employs for cold survival, seasonal changes in supercooling point (SCP), body water content, haemolymph osmolality and antifreeze protein gene (Mpafp) expression were measured over 13 months. Our results show SCPs in M. punctipennis adults changed from -8.0°C in summer to -18.7°C in winter. During winter, adults endured modest water loss; total water decreased from 65.4 percent in summer to 55.9% in winter. Mpafp mRNAs level increased by 13.1 fold from summer to early winter, and haemolymph osmolality increased accordingly from 550 mOsm to 1486 mOsm. Correlation coefficient of Mpafp mRNAs level and SCP indicates that Mpafp mRNA explained 65.3 percent of the variation in SCPs. The correlation between Mpafp mRNA level and total water reflected an indirect influence of antifreeze protein on water content via reducing SCP.

Acute effects of a single warm-water bath on serum adiponectin and leptin levels in healthy men: A pilot study

NASA Astrophysics Data System (ADS)

Shimodozono, Megumi; Matsumoto, Shuji; Ninomiya, Koji; Miyata, Ryuji; Ogata, Atsuko; Etoh, Seiji; Watanabe, Satoshi; Kawahira, Kazumi

2012-09-01

To preliminarily assess the acute effects of a single warm -water bath (WWB) on serum adipokine activity, we measured serum adiponectin, leptin and other metabolic profiles before, immediately after and 30 minutes after WWB in seven healthy male volunteers (mean age, 39.7 ± 6.0 years; mean body mass index, 21.6 ± 1.8 kg/m2). The subjects were immersed in tap water at 41°C for 10 minutes. Two weeks later, the same subjects underwent a single WWB with a bath additive that included inorganic salts and carbon dioxide (WWB with ISCO2) by the same protocol as for the first WWB. Leptin levels significantly increased immediately after WWB with tap water and ISCO2 (both P < 0.05), and remained significantly higher than those at baseline even 30 minutes after WWB with tap water ( P < 0.05). Adiponectin levels showed a slight, but not significant, increase both immediately after and 30 minutes after WWB with tap water or ISCO2. Some parameters, such as serum total cholesterol, red blood cell count, hemoglobin and hematocrit significantly increased immediately after WWB with tap water or ISCO2 (all P < 0.05), but they all returned to the baseline levels 30 minutes after bathing under both conditions. The sublingual temperature rose significantly after 10 minutes of WWB with tap water (0.96 ± 0.16°C relative to baseline, P < 0.01) and after the same duration of WWB with ISCO2 (1.24 ± 0.34°C relative to baseline, P < 0.01). These findings suggest that a single WWB at 41°C for 10 minutes may modulate leptin and adiponectin profiles in healthy men.

Scanning the Horizon: Coast Guard Strategy in a Hot, Flat, Crowded World

DTIC Science & Technology

2010-03-12

Mexico. From 1992 to 2007, deepwater offshore rigs drilling in deep water in the Gulf of Mexico increased from three to 30, and deepwater oil production...discusses the Coast Guard’s Integrated Deepwater System program, which includes recapitalization of its deep-water vessels and aircraft.89 At the...water and ultra deep water drilling. Discussion of increased outer continental shelf activity in higher level strategic planning indicates that

Impact of climate change on waterborne diseases.

PubMed

Funari, Enzo; Manganelli, Maura; Sinisi, Luciana

2012-01-01

Change in climate and water cycle will challenge water availability but it will also increase the exposure to unsafe water. Floods, droughts, heavy storms, changes in rain pattern, increase of temperature and sea level, they all show an increasing trend worldwide and will affect biological, physical and chemical components of water through different paths thus enhancing the risk of waterborne diseases. This paper is intended, through reviewing the available literature, to highlight environmental changes and critical situations caused by floods, drought and warmer temperature that will lead to an increase of exposure to water related pathogens, chemical hazards and cyanotoxins. The final aim is provide knowledge-based elements for more focused adaptation measures.

Potentiometric surface and water-level difference maps of selected confined aquifers of Southern Maryland and Maryland's Eastern Shore, 1975-2011

USGS Publications Warehouse

Curtin, Stephen E.; Andreasen, David C.; Staley, Andrew W.

2012-01-01

Groundwater is the principal source of freshwater supply in most of Southern Maryland and Maryland's Eastern Shore. It is also the source of freshwater supply used in the operation of the Calvert Cliffs, Chalk Point, and Morgantown power plants. Increased groundwater withdrawals over the last several decades have caused groundwater levels to decline. This report presents potentiometric surface maps of the Aquia, Magothy, upper Patapsco, lower Patapsco, and Patuxent aquifers using water levels measured during September 2011. Water-level difference maps also are presented for the first four of these aquifers. The water-level differences in the Aquia aquifer are shown using groundwater-level data from 1982 and 2011, whereas the water-level differences in the Magothy aquifer are presented using data from 1975 and 2011. Water-level difference maps in both the upper Patapsco and lower Patapsco aquifers are presented using data from 1990 and 2011. These maps show cones of depression ranging from 25 to 198 feet (ft) below sea level centered on areas of major withdrawals. Water levels have declined by as much as 112 ft in the Aquia aquifer since 1982, 85 ft in the Magothy aquifer since 1975, and 47 and 71 ft in the upper Patapsco and lower Patapsco aquifers, respectively, since 1990.

Water-Level Conditions in Selected Confined Aquifers of the New Jersey and Delaware Coastal Plain, 2003

USGS Publications Warehouse

dePaul, Vincent T.; Rosman, Robert; Lacombe, Pierre J.

2009-01-01

The Coastal Plain aquifers of New Jersey provide an important source of water for more than 2 million people. Steadily increasing withdrawals from the late 1800s to the early 1990s resulted in declining water levels and the formation of regional cones of depression. In addition to decreasing water supplies, declining water levels in the confined aquifers have led to reversals in natural hydraulic gradients that have, in some areas, induced the flow of saline water from surface-water bodies and adjacent aquifers to freshwater aquifers. In 1978, the U.S. Geological Survey began mapping the potentiometric surfaces of the major confined aquifers of New Jersey every 5 years in order to provide a regional assessment of ground-water conditions in multiple Coastal Plain aquifers concurrently. In 1988, mapping of selected potentiometric surfaces was extended into Delaware. During the fall of 2003, water levels measured in 967 wells in New Jersey, Pennsylvania, northeastern Delaware, and northwestern Maryland were used estimate the potentiometric surface of the principal confined aquifers in the Coastal Plain of New Jersey and five equivalent aquifers in Delaware. Potentiometric-surface maps and hydrogeologic sections were prepared for the confined Cohansey aquifer of Cape May County, the Rio Grande water-bearing zone, the Atlantic City 800-foot sand, the Vincentown aquifer, and the Englishtown aquifer system in New Jersey, as well as for the Piney Point aquifer, the Wenonah-Mount Laurel aquifer, and the Upper Potomac-Raritan-Magothy, the Middle and undifferentiated Potomac-Raritan-Magothy, and the Lower Potomac-Raritan-Magothy aquifers in New Jersey and their equivalents in Delaware. From 1998 to 2003, water levels in many Coastal Plain aquifers in New Jersey remained stable or had recovered, but in some areas, water levels continued to decline as a result of pumping. In the Cohansey aquifer in Cape May County, water levels near the center of the cone of depression underlying the southern part of the peninsula remained about the same as in 1998. To the south, recoveries up to 8 feet were observed in southern Lower Township as withdrawals had decreased since 1998. In the northern part of Cape May County, water levels had not changed substantially from historic conditions. In the Rio Grande water-bearing zone, water levels rose by as much as 13 ft at the Rio Grande well field; elsewhere across the aquifer, little change had occurred. In the Atlantic City 800-foot sand, water-level changes were greatest in southern Cape May County; at the Cape May desalination wells, water levels were as much as 32 ft lower in 2003 than in 1998. In contrast, water levels at the center of a regional cone of depression near Atlantic City rose by as much as 10 ft. Within the Piney Point aquifer water levels rose by 46 ft near Seaside Park. Similarly, water levels increased by more than 30 ft in and around the major cone of depression underlying Dover, Delaware. In the Vincentown aquifer, water levels stabilized or recovered by 2 ft to 6 ft from 1998 to 2003 in most of the wells measured; the exception is near Adelphia in Monmouth County, where water levels rose by as much as 18 ft. From 1998 to 2003, water levels near the center of a large cone of depression that extends from Monmouth to Ocean County recovered by as much as 20 ft in the Wenonah-Mount Laurel aquifer. Concurrently, ground-water levels within the Englishtown aquifer system declined by as much as 13 ft in the same area. Water levels across much of the Upper Potomac-Raritan-Magothy aquifer in the northern Coastal Plain remained about the same as 5 years previous, except in northern Ocean County where ground-water levels declined 10 ft to 33 ft. Water levels in the Middle Potomac-Raritan-Magothy aquifer declined from 5 to 9 ft along the border between Monmouth and Middlesex County. Elsewhere, across the northern part of the Coastal Plain, water levels stabilized within the Cretaceous-a

TIME TO PREGNANCY IN RELATION TO TOTAL TRIHALOMETHANE LEVELS IN TAP WATER

EPA Science Inventory

Time to pregnancy in relation to total trihalomethane levels in tap water
Shanna H. Swan, Cuirong Ren, Gayle C. Windham, Laura Fenster, Kirsten Waller. (University of Missouri and California Department of Health Services).

We have previously reported increased risks o...

CAN FLUORIDATION AFFECT WATER LEAD (II) LEVELS AND LEAD (II) NEUROTOXICITY?

EPA Science Inventory

Recent reports have attempted to show that certain approaches to fluoridating potable water is linked to increased levels of lead(II) in the blood. We examine these claims in light of the established science and critically evaluate their significance. The completeness of hexafl...

Measuring surface-water loss in Honouliuli Stream near the ‘Ewa Shaft, O‘ahu, Hawai‘i

USGS Publications Warehouse

Rosa, Sarah N.

2017-05-30

The Honolulu Board of Water Supply is currently concerned with the possibility of bacteria in the pumped water of the ‘Ewa Shaft (State well 3-2202-21). Groundwater from the ‘Ewa Shaft could potentially be used to meet future potable water needs in the ‘Ewa area on the island of O‘ahu. The source of the bacteria in the pumped water is unknown, although previous studies indicate that surface water may be lost to the subsurface near the site. The ‘Ewa Shaft consists of a vertical shaft, started near the south bank of Honouliuli Stream at an altitude of about 161 feet, and two horizontal infiltration tunnels near sea level. The shaft extracts groundwater from near the top of the freshwater lens in the Waipahu-Waiawa aquifer system within the greater Pearl Harbor Aquifer Sector, a designated Water Management Area.The surface-water losses were evaluated with continuous groundwater-level data from the ‘Ewa Shaft and a nearby monitoring well, continuous stream-discharge data from U.S. Geological Survey streamflow-gaging station 16212490 (Honouliuli Stream at H-1 Freeway near Waipahu), and seepage-run measurements in Honouliuli Stream and its tributary. During storms, discharge at the Honouliuli Stream gaging station increases and groundwater levels at ‘Ewa Shaft and a nearby monitoring well also increase. The concurrent increase in water levels at ‘Ewa Shaft and the nearby monitoring well during storms indicates that regional groundwater-level changes related to increased recharge, reduced withdrawals (due to a decrease in demand during periods of rainfall), or both may be occurring; although these data do not preclude the possibility of local recharge from Honouliuli Stream. Discharge measurements from two seepage runs indicate that surface water in the immediate area adjacent to ‘Ewa Shaft infiltrates into the streambed and may later reach the groundwater system developed by the ‘Ewa Shaft. The estimated seepage loss rates in the vicinity of ‘Ewa Shaft from the two seepage runs generally ranged from 0.27 to 1.78 million gallons per day per mile of stream reach; although higher seepage rates may occur during periods of higher discharge in Honouliuli Stream. A potential source of bacteria in ‘Ewa Shaft maybe related to seepage from Honouliuli Stream; however, other sources of bacteria were not studied and cannot be excluded.

Ground-water, surface-water, and water-chemistry data, Black Mesa area, northeastern Arizona, 2002-03

USGS Publications Warehouse

Truini, Margot; Thomas, Blakemore E.

2004-01-01

The N aquifer is the major source of water in the 5,400-square-mile area of Black Mesa in northeastern Arizona. Availability of water is an important issue in this area because of continued industrial and municipal use, a growing population, and precipitation of about 6 to 14 inches per year. The monitoring program in the Black Mesa area has been operating since 1971 and is designed to determine the long-term effects of ground-water withdrawals from the N aquifer for industrial and municipal uses. The monitoring program includes measurements of (1) ground-water pumping, (2) ground-water levels, (3) spring discharge, (4) surface-water discharge, (5) ground-water chemistry, and (6) periodic testing of ground-water withdrawal meters. In 2002, total ground-water withdrawals were 8,000 acre-feet, industrial use was 4,640 acre-feet, and municipal use was 3,360 acre-feet. From 2001 to 2002, total withdrawals increased by 4 percent, industrial use increased by 2 percent, and municipal use increased by 7 percent. Flowmeter testing was completed for 32 municipal wells in 2003. The median difference between pumping rates for the permanent meter and a test meter for all the sites tested was -2.0 percent. Values ranged from -13.7 percent at Hopi High School no. 2 to +12.9 percent at Shonto PM3. From 2002 to 2003, water levels declined in 5 of 13 wells in the unconfined part of the aquifer, and the median change was 0.0 foot. Water levels declined in 8 of 13 wells in the confined part of the aquifer, and the median change was -1.1 feet. From the prestress period (prior to 1965) to 2003, the median water-level change for 26 wells was -8.3 feet. Median water-level changes were -0.4 foot for 13 wells in the unconfirned part of the aquifer and -60.3 feet for 13 wells in the confined part. Discharges were measured once in 2002 and once in 2003 at four springs. Discharge decreased by 16 percent at Pasture Canyon Spring, increased 10 percent at Moenkopi Spring and 90 percent at an unnamed spring near Dennehotso, and did not change at Burro Spring. For the past 11 years, discharges from the four springs have fluctuated; however, an increasing or decreasing trend is not apparent. Continuous records of surface-water discharge have been collected from 1976 to 2002 at Moenkopi Wash, 1996 to 2002 at Laguna Creek, 1993 to 2002 at Dinnebito Wash, and 1994 to 2002 at Polacca Wash. Median flows for November, December, January, and February of each water year were used as an index of ground-water discharge to those streams. Since 1995, the median winter flows have decreased for Moenkopi Wash, Dinnebito Wash, and Polacca Wash. Since the first continuous record of surface-water discharge in 1997, there is no consistent trend in the median winter flow for Laguna Creek. In 2003, water samples were collected from 12 wells and 4 springs and analyzed for selected chemical constituents. Dissolved-solids concentrations ranged from 118 to 642 milligrams per liter. Water samples from 10 of the wells and from all of the springs had less than 500 milligrams per liter of dissolved solids. There are no appreciable time trends in the chemistry of water samples from 7 wells and 4 springs; 7 wells had more than 8 years of data, and the 4 springs had more than 10 years of data.

Drinking water arsenic exposure and blood pressure in healthy women of reproductive age in Inner Mongolia, China

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kwok, Richard K.; Mendola, Pauline; Liu Zhiyi

2007-08-01

The extremely high exposure levels evaluated in prior investigations relating elevated levels of drinking water arsenic and hypertension prevalence make extrapolation to potential vascular effects at lower exposure levels very difficult. A cross-sectional study was conducted on 8790 women who had recently been pregnant in an area of Inner Mongolia, China known to have a gradient of drinking water arsenic exposure. This study observed increased systolic blood pressure levels with increasing drinking water arsenic, at lower exposure levels than previously reported in the literature. As compared to the referent category (below limit of detection to 20 {mu}g of As/L), themore » overall population mean systolic blood pressure rose 1.29 mm Hg (95% CI 0.82, 1.75), 1.28 mm Hg (95% CI 0.49, 2.07), and 2.22 mm Hg (95% CI 1.46, 2.97) as drinking water arsenic concentration increased from 21 to 50, 51 to 100, and > 100 {mu}g of As/L, respectively. Controlling for age and body weight (n = 3260), the population mean systolic blood pressure rose 1.88 mm Hg (95% CI 1.03, 2.73), 3.90 mm Hg (95% CI 2.52, 5.29), and 6.83 mm Hg (95% CI 5.39, 8.27) as drinking water arsenic concentration increased, respectively. For diastolic blood pressure effect, while statistically significant, was not as pronounced as systolic blood pressure. Mean diastolic blood pressure rose 0.78 mm Hg (95% CI 0.39, 1.16), 1.57 mm Hg (95% CI 0.91, 2.22) and 1.32 mm Hg (95% CI 0.70, 1.95), respectively, for the overall population and rose 2.11 mm Hg (95% CI 1.38, 2.84), 2.74 mm Hg (95% CI 1.55, 3.93), and 3.08 mm Hg (95% CI 1.84, 4.31), respectively, for the adjusted population (n = 3260) at drinking water arsenic concentrations of 21 to 50, 51 to 100, and > 100 {mu}g of As/L. If our study results are confirmed in other populations, the potential burden of cardiovascular disease attributable to drinking water arsenic is significant.« less

Sensitivity of Terrestrial Water and Energy Budgets to CO2-Physiological Forcing: An Investigation Using an Offline Land Model

NASA Technical Reports Server (NTRS)

Gopalakrishnan, Ranjith; Bala, Govindsamy; Jayaraman, Mathangi; Cao, Long; Nemani, Ramakrishna; Ravindranath, N. H.

2011-01-01

Increasing concentrations of atmospheric carbon dioxide (CO2) influence climate by suppressing canopy transpiration in addition to its well-known greenhouse gas effect. The decrease in plant transpiration is due to changes in plant physiology (reduced opening of plant stomata). Here, we quantify such changes in water flux for various levels of CO2 concentrations using the National Center for Atmospheric Research s (NCAR) Community Land Model. We find that photosynthesis saturates after 800 ppmv (parts per million, by volume) in this model. However, unlike photosynthesis, canopy transpiration continues to decline at about 5.1% per 100 ppmv increase in CO2 levels. We also find that the associated reduction in latent heat flux is primarily compensated by increased sensible heat flux. The continued decline in canopy transpiration and subsequent increase in sensible heat flux at elevated CO2 levels implies that incremental warming associated with the physiological effect of CO2 will not abate at higher CO2 concentrations, indicating important consequences for the global water and carbon cycles from anthropogenic CO2 emissions. Keywords: CO2-physiological effect, CO2-fertilization, canopy transpiration, water cycle, runoff, climate change 1.

Analysis of Tests of Subsurface Injection, Storage, and Recovery of Freshwater in Lancaster, Antelope Valley, California

USGS Publications Warehouse

Phillips, Steven P.; Carlson, Carl S.; Metzger, Loren F.; Howle, James F.; Galloway, Devin L.; Sneed, Michelle; Ikehara, Marti E.; Hudnut, Kenneth W.; King, Nancy E.

2003-01-01

Ground-water levels in Lancaster, California, declined more than 200 feet during the 20th century, resulting in reduced ground-water supplies and more than 6 feet of land subsidence. Facing continuing population growth, water managers are seeking solutions to these problems. Injection of imported, treated fresh water into the aquifer system when it is most available and least expensive, for later use during high-demand periods, is being evaluated as part of a management solution. The U.S. Geological Survey, in cooperation with the Los Angeles County Department of Public Works and the Antelope Valley-East Kern Water Agency, monitored a pilot injection program, analyzed the hydraulic and subsidence-related effects of injection, and developed a simulation/optimization model to help evaluate the effectiveness of using existing and proposed wells in an injection program for halting the decline of ground-water levels and avoiding future land subsidence while meeting increasing ground-water demand. A variety of methods were used to measure aquifer-system response to injection. Water levels were measured continuously in nested (multi-depth) piezometers and monitoring wells and periodically in other wells that were within several miles of the injection site. Microgravity surveys were done to estimate changes in the elevation of the water table in the absence of wells and to estimate specific yield. Aquifer-system deformation was measured directly and continuously using a dual borehole extensometer and indirectly using continuous Global Positioning System (GPS), first-order spirit leveling, and an array of tiltmeters. The injected water and extracted water were sampled periodically and analyzed for constituents, including chloride and trihalomethanes. Measured injection rates of about 750 gallons per minute (gal/min) per well at the injection site during a 5-month period showed that injection at or above the average extraction rates at that site (about 800 gal/min) was hydraulically feasible. Analyses of these data took many forms. Coupled measurements of gravity and water-level change were used to estimate the specific yield near the injection wells, which, in turn, was used to estimate areal water-table changes from distributed measurements of gravity change. Values of the skeletal components of aquifer-system storage, which are key subsidence-related characteristics of the system, were derived from continuous measurements of water levels and aquifer-system deformation. A numerical model of ground-water flow was developed for the area surrounding Lancaster and used to estimate horizontal and vertical hydraulic conductivities. A chemical mass balance was done to estimate the recovery of injected water. The ground-water-flow model was used to project changes in ground-water levels for 10 years into the future, assuming no injection, no change in pumping distribution, and forecasted increases in ground-water demand. Simulated ground-water levels decreased throughout the Lancaster area, suggesting that land subsidence would continue as would the depletion of ground-water supplies and an associated loss of well production capacity. A simulation/optimization model was developed to help identify optimal injection and extraction rates for 16 existing and 13 proposed wells to avoid future land subsidence and to minimize loss of well production capacity while meeting increasing ground-water demands. Results of model simulations suggest that these objectives can be met with phased installation of the proposed wells during the 10-year period. Water quality was not considered in the optimization, but chemical-mass-balance results indicate that a sustained injection program likely would have residual effects on the chemistry of ground water.

Concentration and Variety of Carbapenemase Producers in Recreational Coastal Waters Showing Distinct Levels of Pollution

PubMed Central

Paschoal, Raphael P.; Campana, Eloiza H.; Corrêa, Laís L.; Montezzi, Lara F.; Barrueto, Lina R. L.; da Silva, Isadora R.; Castro, Laura de S.

2017-01-01

ABSTRACT Carbapenemase-producing bacteria cause difficult-to-treat infections related to increased mortality in health care settings. Their occurrence has been reported in raw sewage, sewage-impacted rivers, and polluted coastal waters, which may indicate their spread to the community. We assessed the variety and concentration of carbapenemase producers in coastal waters with distinct pollution levels for 1 year. We describe various bacterial species producing distinct carbapenemases not only in unsuitable waters but also in waters considered suitable for primary contact. PMID:28971868

Detection and Measurement of Land Subsidence Using Global Positioning System and Interferometric Synthetic Aperture Radar, Coachella Valley, California, 1998-2000

USGS Publications Warehouse

Sneed, Michelle; Stork, Sylvia V.; Ikehara, Marti E.

2002-01-01

Land subsidence associated with ground-water-level declines has been recognized as a potential problem in Coachella Valley, California. Since the early 1920s, ground water has been a major source of agricultural, municipal, and domestic supply in the valley. Pumping of ground water resulted in water-level declines as large as 15 meters (50 feet) through the late 1940s. In 1949, the importation of Colorado River water to the lower Coachella Valley began, resulting in a reduction in ground-water pumping and a recovery of water levels during the 1950s through the 1970s. Since the late 1970s, demand for water in the valley has exceeded deliveries of imported surface water, resulting in increased pumping and associated ground-water-level declines and, consequently, an increase in the potential for land subsidence caused by aquifer-system compaction. The location, extent, and magnitude of the vertical land-surface changes in Coachella Valley between 1998 and 2000 were determined using Global Positioning System (GPS) and interferometric synthetic aperture radar (InSAR) methods. GPS measurements made at 15 geodetic monuments in the lower Coachella Valley indicate that -34 to +60 millimeters ? 45 millimeters (-0.11 to +0.20 foot ? 0.15 foot) of vertical change in the land surface occurred during the 2-year period. Changes at three of the monuments exceeded the maximum uncertainty of ? 45 millimeters (? 0.15 foot) at the 95-percent confidence level, which indicates that small amounts of uplift occurred at these monuments between October 1998 and August 2000. Water-level measurements made at wells near the three uplifted monuments during this 2-year period indicate that the water levels fluctuate seasonally; water-level measurements made at these wells in September 1998 and September 2000 indicate that the water levels rose slightly near two monuments and declined slightly near the third. The relation between the seasonally fluctuating, but fairly stable, water levels between September 1998 and September 2000 and the slight uplift at the monuments may indicate that the water levels are fluctuating in the elastic range of stress and that the preconsolidation stress of the aquifer system was not exceeded during the 2-year period. Results of the InSAR measurements made between June 17, 1998, and October 4, 2000, indicate that land subsidence, ranging from about 40 to 80 millimeters (0.13 to 0.26 foot), occurred in three areas of the Coachella Valley; near Palm Desert, Indian Wells, and La Quinta. Measurements made between June 17, 1998, and June 2, 1999, indicate that about 15 millimeters (0.05 foot) occurred southeast of Lake Cahuilla. All the subsiding areas coincide with or are near areas where ground-water levels declined between 1998 and 2000; some water levels in 2000 were at the lowest levels in their recorded histories. The coincident areas of subsidence and declining water levels suggest that aquifer-system compaction may be causing subsidence. If the stresses imposed by the historically lowest water levels exceeded the preconsolidation stress, the aquifer-system compaction and associated land subsidence may be permanent. Although the localized character of the subsidence signals look typical of the type of subsidence characteristically caused by localized pumping, the subsidence also may be related to tectonic activity in the valley.

Water-Level Changes in Aquifers of the Atlantic Coastal Plain, Predevelopment to 2000

USGS Publications Warehouse

dePaul, Vincent T.; Rice, Donald E.; Zapecza, Otto S.

2008-01-01

The Atlantic Coastal Plain aquifer system, which underlies a large part of the east coast of the United States, is an important source of water for more than 20 million people. As the population of the region increases, further demand is being placed on those ground-water resources. To define areas of past and current declines in ground-water levels, as well as to document changes in those levels, historical water-level data from more than 4,000 wells completed in 13 regional aquifers in the Atlantic Coastal Plain were examined. From predevelopment to 1980, substantial water-level declines occurred in many areas of the Atlantic Coastal Plain. Regional variability in water-level change in the confined aquifers of the Atlantic Coastal Plain resulted from regional differences in aquifer properties and patterns of ground-water withdrawals. Within the Northern Atlantic Coastal Plain, declines of more than 100 ft were observed in New Jersey, Delaware, Maryland, Virginia, and North Carolina. Regional declines in water levels were most widespread in the deeper aquifers that were most effectively confined?the Upper, Middle, and Lower Potomac aquifers. Within these aquifers, water levels had declined up to 200 ft in southern Virginia and to more than 100 ft in New Jersey, Delaware, Maryland, and North Carolina. Substantial water-level declines were also evident in the regional Lower Chesapeake aquifer in southeastern New Jersey; in the Castle Hayne-Piney Point aquifer in Delaware, Maryland, southern Virginia and east-central North Carolina; in the Peedee-Severn aquifer in east-central New Jersey and southeastern North Carolina; and in the Black Creek-Matawan aquifer in east-central New Jersey and east-central North Carolina. Conversely, declines were least severe in the regional Upper Chesapeake aquifer during this period. In the Southeastern Coastal Plain, declines of more than 100 ft in the Chattahoochee River aquifer occurred in eastern South Carolina and in southwestern Georgia, where water levels had declined approximately 140 and 200 ft from prepumping conditions, respectively. Within the Upper Floridan aquifer, decline was most pronounced in the coastal areas of Georgia and northern Florida where ground-water withdrawals were at their highest. These areas included Savannah, Jesup, and Brunswick, Ga., as well as the St. Marys, Ga. and Fernandina Beach, Fla., area. Regional water levels had declined by 80 ft near Brunswick and Fernandina Beach to as much as 160 ft near Savannah. Since 1980, water levels in many areas have continued to fall; however, in some places the rate at which levels declined has slowed. Conservation measures have served to limit withdrawals in affected areas, moderating or stabilizing water-level decline, and in some cases, resulting in substantial recovery. In other cases, increases in ground-water pumpage have resulted in continued rapid decline in water levels. From 1980 to 2000, water levels across the regional Upper, Middle, and Lower Potomac aquifers continued to decline across large parts of Delaware, Maryland, Virginia, and North Carolina, and water levels had stabilized or recovered throughout much of Long Island and New Jersey. Substantial water-level recovery had also occurred in east-central New Jersey in the Peedee-Severn and Black Creek-Matawan aquifers and in east-central North Carolina in the Castle Hayne-Piney Point aquifer. Substantial declines from about 1980 to about 2000 occurred in the Peedee-Severn aquifer in southern New Jersey, the Beaufort-Aquia aquifer in southern Maryland, and the Black Creek-Matawan and Upper Potomac aquifers in central and southern parts of the coastal plain in North Carolina. From 1980 to about 2000, water levels within the regional Upper Floridan aquifer had generally stabilized in response to shifting withdrawal patterns and reductions in pumpage at many places within the coastal region. Ground-water levels had stabilized and recovered at the ma

The impact of water scarcity on environmental health in selected residential areas in Bulawayo City, Zimbabwe

NASA Astrophysics Data System (ADS)

Nyemba, Anesu; Manzungu, Emmanuel; Masango, Sijabuliso; Musasiwa, Simon

This paper assesses the extent of water scarcity at household level and the resultant environmental health impacts in Bulawayo, Zimbabwe’s second largest city. The paper is based on two separate surveys that were undertaken in low and high income suburbs between June 2007 and January 2008. The first survey investigated the extent and impacts of water scarcity at household level. Data was collected by means of a household questionnaire, key informant interviews, review of clinic records and physical observation. The second survey assessed microbial levels in the main water sources and was complemented by examining water-related disease profiles. Water scarcity was found to be more severe in low income than in high income suburbs. This was a consequence of the city’s skewed water distribution policy which favoured the former and failure by residents of the latter to invest in safer water alternatives. Per capita water consumption in both suburbs was below internationally recommended levels. Microbial assessment indicated presence of coliforms in water obtained from the tap and alternative sources at levels above WHO and Zimbabwean standards. Water scarcity resulted in an increase in the incidence of water-related diseases and environmental contamination. The evidence suggests that water scarcity in Bulawayo represents a huge cost to residents and the environment.

Effect of winds and waves on salt intrusion in the Pearl River estuary

NASA Astrophysics Data System (ADS)

Gong, Wenping; Lin, Zhongyuan; Chen, Yunzhen; Chen, Zhaoyun; Zhang, Heng

2018-02-01

Salt intrusion in the Pearl River estuary (PRE) is a dynamic process that is influenced by a range of factors and to date, few studies have examined the effects of winds and waves on salt intrusion in the PRE. We investigate these effects using the Coupled Ocean-Atmosphere-Wave-Sediment Transport (COAWST) modeling system applied to the PRE. After careful validation, the model is used for a series of diagnostic simulations. It is revealed that the local wind considerably strengthens the salt intrusion by lowering the water level in the eastern part of the estuary and increasing the bottom landward flow. The remote wind increases the water mixing on the continental shelf, elevates the water level on the shelf and in the PRE and pumps saltier shelf water into the estuary by Ekman transport. Enhancement of the salt intrusion is comparable between the remote and local winds. Waves decrease the salt intrusion by increasing the water mixing. Sensitivity analysis shows that the axial down-estuary wind, is most efficient in driving increases in salt intrusion via wind straining effect.

Carbon dioxide water-bath treatment augments peripheral blood flow through the development of angiogenesis.

PubMed

Xu, Yan-Jun; Elimban, Vijayan; Dhalla, Naranjan S

2017-08-01

In this study, we investigated the effects of CO 2 water-bath therapy on blood flow and angiogenesis in the ischemic hind limb, as well as some plasma angiogenic factors in peripheral ischemic model. The hind limb ischemia was induced by occluding the femoral artery for 2 weeks in rats and treated with or without CO 2 water-bath therapy at 37 °C for 4 weeks (20 min treatment every day for 5 days per week). The peak blood flow and minimal and mean blood flow in the ischemic skeletal muscle were markedly increased by the CO 2 water-bath therapy. This increase in blood flow was associated with development of angiogenesis in the muscle, as well as reduction in the ischemia-induced increase in plasma malondialdehyde levels. Although plasma vascular endothelial growth factor and nitric oxide levels were increased in animals with peripheral ischemia, the changes in these biomarkers were not affected by CO 2 water-bath therapy. These results suggest that augmentation of blood flow in the ischemic hind limb by CO 2 water-bath therapy may be due to the development of angiogenesis and reduction in oxidative stress.

The noradrenaline precursor L-DOPS reduces pathology in a mouse model of Alzheimer’s disease

PubMed Central

Kalinin, Sergey; Polak, Paul E.; Lin, Shao Xia; Sakharkar, Amul J.; Pandey, Subhash C.; Feinstein, Douglas L.

2013-01-01

Damage to noradrenergic neurons in the locus coeruleus (LC) is a hallmark of Alzheimer’s disease (AD) and may contribute to disease progression. In 5xFAD transgenic mice, which accumulate amyloid burden at early ages, the LC undergoes stress as evidenced by increased astrocyte activation, neuronal hypertrophy, reduced levels of LC-enriched messenger RNAs (mRNAs), and increased inflammatory gene expression. Central nervous system (CNS) noradrenaline (NA) levels in 5-month-old male 5xFAD mice were increased using the NA precursor L-threo-3,4-dihydroxyphenylserine (L-DOPS). After 1 month, L-DOPS treatment improved learning in the Morris water maze test compared with vehicle-treated mice. L-DOPS increased CNS NA levels, and average latency times in the water maze test were inversely correlated to NA levels. L-DOPS reduced astrocyte activation and Thioflavin-S staining; increased mRNA levels of neprilysin and insulin degrading enzyme, and of several neurotrophins; and increased brain-derived neurotrophic factor protein levels. These data demonstrate the presence of LC stress in a robust mouse model of AD, and suggest that raising CNS NA levels could provide benefit in AD. PMID:21705113

The noradrenaline precursor L-DOPS reduces pathology in a mouse model of Alzheimer's disease.

PubMed

Kalinin, Sergey; Polak, Paul E; Lin, Shao Xia; Sakharkar, Amul J; Pandey, Subhash C; Feinstein, Douglas L

2012-08-01

Damage to noradrenergic neurons in the locus coeruleus (LC) is a hallmark of Alzheimer's disease (AD) and may contribute to disease progression. In 5xFAD transgenic mice, which accumulate amyloid burden at early ages, the LC undergoes stress as evidenced by increased astrocyte activation, neuronal hypertrophy, reduced levels of LC-enriched messenger RNAs (mRNAs), and increased inflammatory gene expression. Central nervous system (CNS) noradrenaline (NA) levels in 5-month-old male 5xFAD mice were increased using the NA precursor L-threo-3,4-dihydroxyphenylserine (L-DOPS). After 1 month, L-DOPS treatment improved learning in the Morris water maze test compared with vehicle-treated mice. L-DOPS increased CNS NA levels, and average latency times in the water maze test were inversely correlated to NA levels. L-DOPS reduced astrocyte activation and Thioflavin-S staining; increased mRNA levels of neprilysin and insulin degrading enzyme, and of several neurotrophins; and increased brain-derived neurotrophic factor protein levels. These data demonstrate the presence of LC stress in a robust mouse model of AD, and suggest that raising CNS NA levels could provide benefit in AD. Copyright © 2012 Elsevier Inc. All rights reserved.

Lake level fluctuations boost toxic cyanobacterial "oligotrophic blooms".

PubMed

Callieri, Cristiana; Bertoni, Roberto; Contesini, Mario; Bertoni, Filippo

2014-01-01

Global warming has been shown to strongly influence inland water systems, producing noticeable increases in water temperatures. Rising temperatures, especially when combined with widespread nutrient pollution, directly favour the growth of toxic cyanobacteria. Climate changes have also altered natural water level fluctuations increasing the probability of extreme events as dry periods followed by heavy rains. The massive appearance of Dolichospermum lemmermannii ( = planktonic Anabaena), a toxic species absent from the pelagic zone of the subalpine oligotrophic Lake Maggiore before 2005, could be a consequence of the unusual fluctuations of lake level in recent years. We hypothesized that these fluctuations may favour the cyanobacterium as result of nutrient pulses from the biofilms formed in the littoral zone when the lake level is high. To help verify this, we exposed artificial substrates in the lake, and evaluated their nutrient enrichment and release after desiccation, together with measurements of fluctuations in lake level, precipitation and D. lemmermannii population. The highest percentage of P release and the lowest C:P molar ratio of released nutrients coincided with the summer appearance of the D. lemmermannii bloom. The P pulse indicates that fluctuations in level counteract nutrient limitation in this lake and it is suggested that this may apply more widely to other oligotrophic lakes. In view of the predicted increase in water level fluctuations due to climate change, it is important to try to minimize such fluctuations in order to mitigate the occurrence of cyanobacterial blooms.

Effect of increasing bromide concentration on toxicity in treated drinking water.

PubMed

Sawade, Emma; Fabris, Rolando; Humpage, Andrew; Drikas, Mary

2016-04-01

Research is increasingly indicating the potential chronic health effects of brominated disinfection by-products (DBPs). This is likely to increase with elevated bromide concentrations resulting from the impacts of climate change, projected to include extended periods of drought and the sudden onset of water quality changes. This will demand more rigorous monitoring throughout distribution systems and improved water quality management at water treatment plants (WTPs). In this work the impact of increased bromide concentration on formation of DBPs following conventional treatment and chlorination was assessed for two water sources. Bioanalytical tests were utilised to determine cytotoxicity of the water post disinfection. Coagulation was shown to significantly reduce the cytotoxicity of the water, indicating that removal of natural organic matter DBP precursors continues to be an important factor in drinking water treatment. Most toxic species appear to form within the first half hour following disinfectant addition. Increasing bromide concentration across the two waters was shown to increase the formation of trihalomethanes and shifted the haloacetic acid species distribution from chlorinated to those with greater bromine substitution. This correlated with increasing cytotoxicity. This work demonstrates the challenges faced by WTPs and the possible effects increasing levels of bromide in source waters could have on public health.

Biomass Allocation Patterns Are Linked to Genotypic Differences in Whole-Plant Transpiration Efficiency in Sunflower

PubMed Central

Velázquez, Luciano; Alberdi, Ignacio; Paz, Cosme; Aguirrezábal, Luis

2017-01-01

Increased transpiration efficiency (the ratio of biomass to water transpired, TE) could lead to increased drought tolerance under some water deficit scenarios. Intrinsic (i.e., leaf-level) TE is usually considered as the primary source of variation in whole-plant TE, but empirical data usually contradict this assumption. Sunflower has a significant variability in TE, but a better knowledge of the effect of leaf and plant-level traits could be helpful to obtain more efficient genotypes for water use. The objective of this study was, therefore, to assess if genotypic variation in whole-plant TE is better related to leaf- or plant-level traits. Three experiments were conducted, aimed at verifying the existence of variability in whole-plant TE and whole-plant and leaf-level traits, and to assess their correlation. Sunflower public inbred lines and a segregating population of recombinant inbred lines were grown under controlled conditions and subjected to well-watered and water-deficit treatments. Significant genotypic variation was found for TE and related traits. These differences in whole-plant transpiration efficiency, both between genotypes and between plants within each genotype, showed no association to leaf-level traits, but were significantly and negatively correlated to biomass allocation to leaves and to the ratio of leaf area to total biomass. These associations are likely of a physiological origin, and not only a consequence of genetic linkage in the studied population. These results suggest that genotypic variation for biomass allocation could be potentially exploited as a source for increased transpiration efficiency in sunflower breeding programmes. It is also suggested that phenotyping for TE in this species should not be restricted to leaf-level measurements, but also include measurements of plant-level traits, especially those related to biomass allocation between photosynthetic and non-photosynthetic organs. PMID:29204153

Biomass Allocation Patterns Are Linked to Genotypic Differences in Whole-Plant Transpiration Efficiency in Sunflower.

PubMed

Velázquez, Luciano; Alberdi, Ignacio; Paz, Cosme; Aguirrezábal, Luis; Pereyra Irujo, Gustavo

2017-01-01

Increased transpiration efficiency (the ratio of biomass to water transpired, TE) could lead to increased drought tolerance under some water deficit scenarios. Intrinsic (i.e., leaf-level) TE is usually considered as the primary source of variation in whole-plant TE, but empirical data usually contradict this assumption. Sunflower has a significant variability in TE, but a better knowledge of the effect of leaf and plant-level traits could be helpful to obtain more efficient genotypes for water use. The objective of this study was, therefore, to assess if genotypic variation in whole-plant TE is better related to leaf- or plant-level traits. Three experiments were conducted, aimed at verifying the existence of variability in whole-plant TE and whole-plant and leaf-level traits, and to assess their correlation. Sunflower public inbred lines and a segregating population of recombinant inbred lines were grown under controlled conditions and subjected to well-watered and water-deficit treatments. Significant genotypic variation was found for TE and related traits. These differences in whole-plant transpiration efficiency, both between genotypes and between plants within each genotype, showed no association to leaf-level traits, but were significantly and negatively correlated to biomass allocation to leaves and to the ratio of leaf area to total biomass. These associations are likely of a physiological origin, and not only a consequence of genetic linkage in the studied population. These results suggest that genotypic variation for biomass allocation could be potentially exploited as a source for increased transpiration efficiency in sunflower breeding programmes. It is also suggested that phenotyping for TE in this species should not be restricted to leaf-level measurements, but also include measurements of plant-level traits, especially those related to biomass allocation between photosynthetic and non-photosynthetic organs.

Nitrates in drinking water and methemoglobin levels in pregnancy: a longitudinal study.

PubMed

Manassaram, Deana M; Backer, Lorraine C; Messing, Rita; Fleming, Lora E; Luke, Barbara; Monteilh, Carolyn P

2010-10-14

Private water systems are more likely to have nitrate levels above the maximum contaminant level (MCL). Pregnant women are considered vulnerable to the effects of exposure to high levels of nitrates in drinking water due to their altered physiological states. The level of methemoglobin in the blood is the biomarker often used in research for assessing exposure to nitrates. The objective of this study was to assess methemoglobin levels and examine how various factors affected methemoglobin levels during pregnancy. We also examined whether differences in water use practices existed among pregnant women based on household drinking water source of private vs. public supply. A longitudinal study of 357 pregnant women was conducted. Longitudinal regression models were used to examine changes and predictors of the change in methemoglobin levels over the period of gestation. Pregnant women showed a decrease in methemoglobin levels with increasing gestation although <1% had levels above the physiologic normal of 2% methemoglobin, regardless of the source of their drinking water. The multivariable analyses did not show a statistically significant association between methemoglobin levels and the estimated nitrate intake from tap water among pregnant women around 36 weeks gestation (β = 0.046, p = 0.986). Four women had tap water nitrate levels above the MCL of 10 mg/L. At enrollment, a greater proportion of women who reported using water treatment devices were private wells users (66%) compared to public system users (46%) (p < 0.0001). Also, a greater proportion of private well users (27%) compared to public system users (13%) were using devices capable of removing nitrate from water (p < 0.0001). Pregnant women potentially exposed to nitrate levels primarily below the MCL for drinking water were unlikely to show methemoglobin levels above the physiologic normal. Water use practices such as the use of treatment devices to remove nitrates varied according to water source and should be considered in the assessment of exposure to nitrates in future studies.

Nitrates in drinking water and methemoglobin levels in pregnancy: a longitudinal study

PubMed Central

2010-01-01

Background Private water systems are more likely to have nitrate levels above the maximum contaminant level (MCL). Pregnant women are considered vulnerable to the effects of exposure to high levels of nitrates in drinking water due to their altered physiological states. The level of methemoglobin in the blood is the biomarker often used in research for assessing exposure to nitrates. The objective of this study was to assess methemoglobin levels and examine how various factors affected methemoglobin levels during pregnancy. We also examined whether differences in water use practices existed among pregnant women based on household drinking water source of private vs. public supply. Methods A longitudinal study of 357 pregnant women was conducted. Longitudinal regression models were used to examine changes and predictors of the change in methemoglobin levels over the period of gestation. Results Pregnant women showed a decrease in methemoglobin levels with increasing gestation although <1% had levels above the physiologic normal of 2% methemoglobin, regardless of the source of their drinking water. The multivariable analyses did not show a statistically significant association between methemoglobin levels and the estimated nitrate intake from tap water among pregnant women around 36 weeks gestation (β = 0.046, p = 0.986). Four women had tap water nitrate levels above the MCL of 10 mg/L. At enrollment, a greater proportion of women who reported using water treatment devices were private wells users (66%) compared to public system users (46%) (p < 0.0001). Also, a greater proportion of private well users (27%) compared to public system users (13%) were using devices capable of removing nitrate from water (p < 0.0001). Conclusion Pregnant women potentially exposed to nitrate levels primarily below the MCL for drinking water were unlikely to show methemoglobin levels above the physiologic normal. Water use practices such as the use of treatment devices to remove nitrates varied according to water source and should be considered in the assessment of exposure to nitrates in future studies. PMID:20946657

Planning for the Electricity-Water Nexus

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tidwell, Vincent Carroll

2015-02-01

Energy production requires water, while the conveyance, storage, and treatment of water requires energy—this is the energy-water nexus. The importance of this nexus has recently been highlighted by droughts reducing hydropower production, heat waves impacting stream water temperatures forcing nuclear and coal-fired power plants to suspend operations, floods and hurricanes damaging energy infrastructure, and the denial of new power plant permits due to limited water availability. All this while the energy intensity of the water sector is increasing as water is moved from more distant locations and increasing water treatment is required. Tackling this energy-water nexus will require significant coordinationmore » between water and energy managers from the local to the federal level.« less

Summary of the Ground-Water-Level Hydrologic Conditions in New Jersey 2006

USGS Publications Warehouse

Jones, Walter; Pope, Daryll

2007-01-01

Ground water is one of the Nation's most important natural resources. It provides about 40 percent of our Nation's public water supply. Currently, nearly one-half of New Jersey's drinking-water is supplied by over 300,000 wells that serve more than 4.3 million people (John P. Nawyn, U.S. Geological Survey, written commun., 2007). New Jersey's population is projected to grow by more than a million people by 2030 (U.S. Census Bureau, accessed March 2, 2006, at http://www.census.gov). As demand for water increases, managing the development and use of the ground-water resource so that the supply can be maintained for an indefinite time without causing unacceptable environmental, economic, or social consequences is of paramount importance. This report describes the U.S. Geological Survey (USGS) New Jersey Water Science Center Observation Well Networks. Record low ground-water levels during water year 2006 (October 1, 2005 to September 30, 2006) are listed, and water levels in six selected water-table observation wells and three selected confined wells are shown in hydrographs. The report describes the trends in water levels in various confined aquifers in southern New Jersey and in water-table and fracture rock aquifers throughout the State. Web site addresses to access the data also are included. The USGS has operated a network of observation wells in New Jersey since 1923 for the purpose of monitoring ground-water-level changes throughout the State. Long-term systematic measurement of water levels in observation wells provides the data needed to evaluate changes in the ground-water resource over time. Records of ground-water levels are used to evaluate the effects of climate changes and water-supply development, to develop ground-water models, and to forecast trends.

Hydrogeology of, water withdrawal from, and water levels and chloride concentrations in the major Coastal Plain aquifers of Gloucester and Salem Counties, New Jersey

USGS Publications Warehouse

Cauller, S.J.; Carleton, G.B.; Storck, M.J.

1999-01-01

Eight aquifers underlying Gloucester and Salem Counties in the southwestern Coastal Plain of New Jersey provide nearly all the drinking water for the 295,000 people who live in the area. Ground-water withdrawals in the two-county area and adjoining counties have affected water levels in several of these aquifers. Ground-water withdrawals in the two-county area also have affected the quality of water, increasing the chloride concentration in several of the aquifers as a result of saltwater intrusion. This report contains hydrologic data from the two-county area, including geometry and extent of hydrogeologic units, thickness and altitude of each aquifer, withdrawals from and water levels in major aquifers, and chloride concentrations in water from each aquifer. Reported ground-water withdrawals in Gloucester and Salem Counties during 1975-95 averaged 7,800 Mgal/yr (million gallons per year) for public supply, 4,900 Mgal/yr for industrial use, 700 Mgal/yr for irrigation, 500 Mgal/yr for power plants, 50 Mgal/yr for commercial use, and about 40 Mgal/yr for mining. Withdrawals for domestic self-supply in 1994 are estimated to be about 2,600 Mgal/yr, but only about 20 percent (520 Mgal/yr) is thought to be consumptive use; the remainder is returned to the aquifer through septic systems. The most heavily used aquifer in Salem and Gloucester Counties is the Upper Potomac-Raritan-Magothy aquifer, followed by, in decreasing order of use, the Middle Potomac-Raritan-Magothy aquifer, the Lower Potomac-Raritan-Magothy aquifer, the Kirkwood-Cohansey aquifer system, and the Wenonah-Mount Laurel aquifer. Reported withdrawals from these aquifers during 1975-95 averaged 5,000, 3,700, 3,200, and 330 Mgal/yr, respectively. Withdrawals from the Wenonah-Mount Laurel aquifer in Gloucester County increased during 1993-96 because of New Jersey Department of Environmental Protection restrictions on new withdrawals from the deeper Potomac-Raritan-Magothy aquifer system. Because of the increased rate of withdrawal, water-level altitudes in the Wenonah-Mount Laurel aquifer in some parts of the two counties in 1996 were from 5 to 40 ft lower than water levels measured in 1993 and previous years, reaching a low of almost 40 ft below sea level in Washington Township, Gloucester County. Ground water in the Upper, Middle, and Lower Potomac-Raritan-Magothy aquifers in the study area is withdrawn from the outcrop areas near the Delaware River downdip to the Glassboro vicinity. Water-level altitudes in 1993 in the three aquifers were near sea level in the outcrop areas near the Delaware River, but were as low as 80 ft below sea level in parts of Gloucester County that were affected by withdrawals in Camden County and were 20 to 60 ft below sea level near major withdrawal centers in the study area. Chloride concentrations in water samples from selected wells in seven aquifers throughout Gloucester and Salem Counties have been monitored since 1949. These aquifers include the Kirkwood-Cohansey aquifer system, the Vincentown and Wenonah-Mount Laurel aquifers, the Englishtown aquifer system, and the Upper, Middle, and Lower Potomac-Raritan-Magothy aquifers. The results of chloride analyses of 4,221 samples from 496 wells indicate the extent and magnitude of saltwater intrusion in these aquifers, six of which have been affected to varying degrees by saltwater intrusion. The confined Piney Point aquifer and the unconfined Kirkwood-Cohansey aquifer system show no measurable effects of saltwater intrusion in the study area. Chloride concentrations in water from selected public-supply wells screened in the Upper, Middle, and Lower Potomac-Raritan-Magothy aquifers have increased over time in communities along the Delaware River and further inland in both Gloucester and Salem Counties. Elevated chloride concentrations in the Potomac-Raritan-Magothy aquifer system are widespread in this area but rarely exceed the drinking-water standard of 250 milligrams per liter.

Ground-Water Occurrence and Movement, 2006, and Water-Level Changes in the Detrital, Hualapai, and Sacramento Valley Basins, Mohave County, Arizona

USGS Publications Warehouse

Anning, David W.; Truini, Margot; Flynn, Marilyn E.; Remick, William H.

2007-01-01

Ground-water levels for water year 2006 and their change over time in Detrital, Hualapai, and Sacramento Valley Basins of northwestern Arizona were investigated to improve the understanding of current and past ground-water conditions in these basins. The potentiometric surface for ground water in the Basin-Fill aquifer of each basin is generally parallel to topography. Consequently, ground-water movement is generally from the mountain front toward the basin center and then along the basin axis toward the Colorado River or Lake Mead. Observed water levels in Detrital, Hualapai, and Sacramento Valley Basins have fluctuated during the period of historic water-level records (1943 through 2006). In Detrital Valley Basin, water levels in monitored areas have either remained the same, or have steadily increased as much as 3.5 feet since the 1980s. Similar steady conditions or water-level rises were observed for much of the northern and central parts of Hualapai Valley Basin. During the period of historic record, steady water-level declines as large as 60 feet were found in wells penetrating the Basin-Fill aquifer in areas near Kingman, northwest of Hackberry, and northeast of Dolan Springs within the Hualapai Valley Basin. Within the Sacramento Valley Basin, during the period of historic record, water-level declines as large as 55 feet were observed in wells penetrating the Basin-Fill aquifer in the Kingman and Golden Valley areas; whereas small, steady rises were observed in Yucca and in the Dutch Flat area.

Agent-Based Modelling of Agricultural Water Abstraction in Response to Climate, Policy, and Demand Changes: Results from East Anglia, UK

NASA Astrophysics Data System (ADS)

Swinscoe, T. H. A.; Knoeri, C.; Fleskens, L.; Barrett, J.

2014-12-01

Freshwater is a vital natural resource for multiple needs, such as drinking water for the public, industrial processes, hydropower for energy companies, and irrigation for agriculture. In the UK, crop production is the largest in East Anglia, while at the same time the region is also the driest, with average annual rainfall between 560 and 720 mm (1971 to 2000). Many water catchments of East Anglia are reported as over licensed or over abstracted. Therefore, freshwater available for agricultural irrigation abstraction in this region is becoming both increasingly scarce due to competing demands, and increasingly variable and uncertain due to climate and policy changes. It is vital for water users and policy makers to understand how these factors will affect individual abstractors and water resource management at the system level. We present first results of an Agent-based Model that captures the complexity of this system as individual abstractors interact, learn and adapt to these internal and external changes. The purpose of this model is to simulate what patterns of water resource management emerge on the system level based on local interactions, adaptations and behaviours, and what policies lead to a sustainable water resource management system. The model is based on an irrigation abstractor typology derived from a survey in the study area, to capture individual behavioural intentions under a range of water availability scenarios, in addition to farm attributes, and demographics. Regional climate change scenarios, current and new abstraction licence reforms by the UK regulator, such as water trading and water shares, and estimated demand increases from other sectors were used as additional input data. Findings from the integrated model provide new understanding of the patterns of water resource management likely to emerge at the system level.

Stimulation-induced decreases in the diffusion of extra-vascular water in the human visual cortex: a window in time and space on mechanisms of brain water transport and economy.

PubMed

Baslow, Morris H; Hu, Caixia; Guilfoyle, David N

2012-07-01

In a human magnetic resonance diffusion-weighted imaging (DWI) investigation at 3 T and high diffusion sensitivity weighting (b = 1,800 s/mm(2)), which emphasizes the contribution of water in the extra-vascular compartment and minimizes that of the vascular compartment, we observed that visual stimulation with a flashing checkerboard at 8 Hz for a period of 600 s in eight subjects resulted in significant increases in DWI signals (mean +2.70%, range +0.51 to 8.54%). The increases in DWI signals in activated areas of the visual cortex indicated that during stimulation, the apparent diffusion coefficient (ADC) of extra-vascular compartment water decreased. In response to continuous stimulation, DWI signals gradually increased from pre-stimulation controls, leveling off after 400-500 s. During recovery from stimulation, DWI signals gradually decreased, approaching control levels in 300-400 s. In this study, we show for the first time that the effects of visual stimulation on DWI signals in the human visual cortex are cumulative over an extended period of time. We propose that these relatively slow stimulation-induced changes in the ADC of water in the extra-vascular compartment are due to transient changes in the ratio of faster diffusing free water to slower diffusing bound water and reflect brain water transport processes between the vascular and extra-vascular compartments at the cellular level. The nature of these processes including possible roles of the putative glucose water import and N-acetylaspartate water export molecular water pumps in brain function are discussed.

Hydrologic assessment of three drainage basins in the Pinelands of southern New Jersey, 2004-06

USGS Publications Warehouse

Walker, Richard L.; Nicholson, Robert S.; Storck, Donald A.

2011-01-01

The New Jersey Pinelands is an ecologically diverse area in the southern New Jersey Coastal Plain, most of which overlies the Kirkwood-Cohansey aquifer system. The demand for groundwater from this aquifer system is increasing as local development increases. Because any increase in groundwater withdrawals has the potential to affect streamflows and wetland water levels, and ultimately threaten the ecological health and diversity of the Pinelands ecosystem, the U.S. Geological Survey, in cooperation with the New Jersey Pinelands Commission, began a multi-phase hydrologic investigation in 2004 to characterize the hydrologic system supporting the aquatic and wetland communities of the New Jersey Pinelands area (Pinelands). The current investigation of the hydrology of three representative drainage basins in the Pinelands (Albertson Brook, McDonalds Branch, and Morses Mill Stream basins) included a compilation of existing data; collection of water-level and streamflow data; mapping of the water-table altitude and depth to the water table; and analyses of water-level and streamflow variability, subsurface gradients and flow patterns, and water budgets. During 2004-06, a hydrologic database of existing and new data from wells and stream sites was compiled. Methods of data collection and analysis were defined, and data networks consisting of 471 wells and 106 surface-water sites were established. Hydrographs from 26 water-level-monitoring wells and four streamflow-gaging stations were analyzed to show the response of water levels and streamflow to precipitation and recharge with respect to the locations of these wells and streams within each basin. Water-level hydrographs show varying hydraulic gradients and flow potentials, and indicate that responses to recharge events vary with well depth and proximity to recharge and discharge areas. Results of the investigation provide a detailed characterization of hydrologic conditions, processes, and relations among the components of the hydrologic cycle in the Pinelands. In the Pinelands, recharge replenishes the aquifer system and contributes to groundwater flow, most of which moves to wetlands and surface water where natural discharge occurs. Some groundwater flow is intercepted by supply wells. Recharge rates generally are highest during the non-growing season and are inversely related to evapotranspiration. Analysis of subsurface hydraulic gradients, water-table fluctuations, and streamflow variability indicates a strong linkage between groundwater and wetlands, lakes and streams. Gradient analysis indicates that most wetlands are in groundwater discharge areas, but some wetlands are in groundwater recharge areas. The depth to the water table ranges from zero at surface-water features up to about 10 meters in topographically high areas. Depth to water fluctuates seasonally, and the magnitude of these fluctuations generally increases with distance from surface water. Variations in the permeability of the soils and sediments of the aquifer system strongly affect patterns of water movement through the subsurface and the interaction of groundwater with wetlands, lakes and streams. Mean annual streamflow during 2004-06 ranged from 83 to 106 percent of the long-term mean annual discharge, indicating that the data-collection period can be considered representative of average conditions. Measurements of groundwater levels, stream stage, and stream discharge and locations of start-of-flow are illustrated in basin-wide maps of water-table altitude, depth to the water table, and stream base flow during the period. Water-level data collected along 15 hydrologic transects that span the range of environments from uplands through wetlands to surface water were used to determine hydraulic gradients, potential flow directions, and areas of recharge and discharge. These data provide information about the localized interactions of groundwater with wetlands and surface water. Wetlands were categorized with r

Acute Toxicity of Ammonia, Nitrite and Nitrate to Shrimp Litopenaeus vannamei Postlarvae in Low-Salinity Water.

PubMed

Valencia-Castañeda, Gladys; Frías-Espericueta, Martin G; Vanegas-Pérez, Ruth C; Pérez-Ramírez, Jesús A; Chávez-Sánchez, María C; Páez-Osuna, Federico

2018-05-12

Shrimp farming in low salinities waters is an alternative to increasing production, and counteracting disease problems in brackish and marine waters. However, in low-salinity waters, toxicity of nitrogen compounds increases, and there is no available data of its acute toxicity in shrimp postlarvae. This study determined the acute toxicity of ammonia, nitrite and nitrate in Litopenaeus vannamei postlarvae in 1 and 3 g/L salinity, as well as the safety levels. The LC 50 confirms that nitrite is more toxic than ammonia and nitrate in low salinity waters, and that its toxicity increases with a decrease in salinity. The safe levels estimated for salinities of 1 and 3 g/L were 0.54 and 0.81 mg/L for total ammonia-N, 0.17 and 0.25 mg/L for NO 2 -N, and 5.6 and 21.5 mg/L for NO 3 -N, respectively.

Analog model study of the ground-water basin of the Upper Coachella Valley, California

USGS Publications Warehouse

Tyley, Stephen J.

1974-01-01

An analog model of the ground-water basin of the upper Coachella Valley was constructed to determine the effects of imported water on ground-water levels. The model was considered verified when the ground-water levels generated by the model approximated the historical change in water levels of the ground-water basin caused by man's activities for the period 1986-67. The ground-water basin was almost unaffected by man's activities until about 1945 when ground-water development caused the water levels to begin to decline. The Palm Springs area has had the largest water-level decline, 75 feet since 1986, because of large pumpage, reduced natural inflow from the San Gorgonio Pass area, and diversions of natural inflows at Snow and Falls Creeks and Chino Canyon starting in 1945. The San Gorgonio Pass inflow had been reduced from about 18,000 acre-feet in 1986 to about 9,000 acre-feet by 1967 because of increased ground-water pumpage in the San Gorgonio Pass area, dewatering of the San Gorgonio Pass area that took place when the tunnel for the Metropolitan Water District of Southern California was drilled, and diversions of surface inflow at Snow and Falls Creeks. In addition, 1944-64 was a period of below-normal precipitation which, in part, contributed to the declines in water levels in the Coachella Valley. The Desert Hot Springs, Garnet Hill, and Mission Creek subbasins have had relatively little development; consequently, the water-level declines have been small, ranging from 5 to 15 feet since 1986. In the Point Happy area a decline of about 2 feet per year continued until 1949 when delivery of Colorado River water to the lower valley through the Coachella Canal was initiated. Since 1949 the water levels in the Point Happy area have been rising and by 1967 were above their 1986 levels. The Whitewater River subbasin includes the largest aquifer in the basin, having sustained ground-water pumpage of about 740,000 acre-feet from 1986 to 1967, and will probably continue to provide the most significant supply of ground water for the upper valley. The total ground-water storage depletion for the entire upper valley for 1986-67 was about 600,000 acre-feet, an average storage decrease of about 25,000 acre-feet per year since 1945. Transmissivity for the Whitewater River subbasin ranges from 860,000 gallons per day per foot (near Point Happy) to 50,000 gallons per day per foot, with most of the subbasin about 800,000 gallons per day per foot. In contrast, the transmissivities of the Desert Hot Springs, Mission Creek, and Garnet Hill subbasins generally range from 2,000 to 100,000, but the highest value, beneath the Mission Creek streambed deposits, is 200,000 gallons per day per foot; the transmissivity for most of the area of th6 three subbasins is 80,000 gallons per day per foot. The storage coefficients are representative of water-table conditions, ranging from 0.18 beneath the Mission Creek stream deposits to 0.06 in the Palm Springs area. The model indicated that the outflow at Point Happy decreased from 50,000 acre-feet in 1936 to 30,000 acre-feet by 1967 as a result of the rising water levels in the lower valley. The most logical area to recharge the Colorado River water is the Windy Point-Whitewater area, where adequate percolation rates of 2-4 acre-feet per acre per day are probable. The Whitewater River bed may be the best location to spread the water if the largest part of the imported water can be recharged during low-flow periods. The area in sec. 21, T. 2 S., R. 4 E., would be adequate for the smaller quantities of recharge proposed for the Mission Creek area. Projected pumpage for the period 1968-2000 was programmed on the model with the proposed recharge of Colorado River water for the same period. The model indicated a maximum water-level increase of 200 feet above the 1967 water level at Windy Point, the proposed recharge site, by the year 2000, a 130-foot increase by 1990, and a 20-foot increas

Combined effects of projected sea level rise, storm surge, and peak river flows on water levels in the Skagit Floodplain

USGS Publications Warehouse

Hamman, Josheph J; Hamlet, Alan F.; Fuller, Roger; Grossman, Eric E.

2016-01-01

Current understanding of the combined effects of sea level rise (SLR), storm surge, and changes in river flooding on near-coastal environments is very limited. This project uses a suite of numerical models to examine the combined effects of projected future climate change on flooding in the Skagit floodplain and estuary. Statistically and dynamically downscaled global climate model scenarios from the ECHAM-5 GCM were used as the climate forcings. Unregulated daily river flows were simulated using the VIC hydrology model, and regulated river flows were simulated using the SkagitSim reservoir operations model. Daily tidal anomalies (TA) were calculated using a regression approach based on ENSO and atmospheric pressure forcing simulated by the WRF regional climate model. A 2-D hydrodynamic model was used to estimate water surface elevations in the Skagit floodplain using resampled hourly hydrographs keyed to regulated daily flood flows produced by the reservoir simulation model, and tide predictions adjusted for SLR and TA. Combining peak annual TA with projected sea level rise, the historical (1970–1999) 100-yr peak high water level is exceeded essentially every year by the 2050s. The combination of projected sea level rise and larger floods by the 2080s yields both increased flood inundation area (+ 74%), and increased average water depth (+ 25 cm) in the Skagit floodplain during a 100-year flood. Adding sea level rise to the historical FEMA 100-year flood resulted in a 35% increase in inundation area by the 2040's, compared to a 57% increase when both SLR and projected changes in river flow were combined.

Numerical Simulation of Regional Changes in Ground-Water Levels and in the Freshwater-Saltwater Interface Induced by Increased Pumpage at Barbers Point Shaft, Oahu, Hawaii

USGS Publications Warehouse

Souza, William R.; Meyer, William

1995-01-01

The effect on the regional ground-water system of southern Oahu from increased pumpage at Barbers Point shaft was estimated by a numerical ground-water model developed for the Oahu Regional Aquifer Systems Analysis (RASA) study. The RASA model was updated by revising pumping and ground-water recharge data. Pumpage data used in the new simulations were based on the allocated pumping rates for 1995 as set by the State Commission on Water Resource Management. On the basis of numerical simulation, Barbers Point shaft can sustain a withdrawal rate of 4.34 million gallons per day without adversely affecting wells in the Waianae aquifer. From results of numerical simulations, it is estimated that, as a result of increasing pumpage in Barbers Point shaft by 2 million gallons per day above the 1995-allocated rate of 2.337 million gallons per day, regional declines in ground-water levels will be about 0.4 to 0.7 feet throughout the Waianae aquifer and about 0.8 ft at the shaft. The corresponding rise of the freshwater-saltwater interface, as a result of declines in ground-water levels, is estimated to be about 20 to 30 feet. Numerical simulation also indicates that changes in ground-water levels greater than about 0.1 feet do not extend across either the Waianae-Koolau unconformity or the south Schofield barrier. The model-estimated position of the freshwater-saltwater interface, as a result of additional pumpage, ranges from 500 to 860 feet below sea level in the southern and northern parts of the aquifer, respectively, and about 540 feet below sea level at the shaft. On the basis of an estimate of the thickness of the transition-zone, the freshwater lens would remain about 240 feet thick below the shaft. In addition, the estimated declines in ground-water levels throughout the aquifer are small compared with the thickness of the freshwater lens and these declines would not be expected to affect the yields of other wells in terms of quantity. Chloride concentrations in the water pumped at Barbers Point shaft were about 240 milligrams per liter in 1992. The estimated background chloride concentration is 200 to 220 milligrams per liter because of low rainfall and the contamination of recharge water from natural salt accumulation in the soil. A reduction in irrigation through 1995 is expected to reduce recharge to the aquifer from irrigation-return water and chloride concentrations associated with the irrigation water throughout the Waianae aquifer. As a result of these combined effects, chloride concentrations of water pumped from the Barbers Point shaft will likely decrease, although the length of time required for this lowering is unknown.

Water budget considerations regarding groundwater extraction targets in the Calera Aquifer watershed, Mexico

USDA-ARS?s Scientific Manuscript database

Groundwater extraction from the Calera Aquifer in the State of Zacatecas, Mexico, for irrigation, urban, and industrial uses has increased over recent decades to unsustainable levels. An annual, watershed-scale water budget analysis was conducted to identify alternative water conservation and water...

Flint Water Crisis Caused By Interrupted Corrosion Control: Investigating "Ground Zero" Home.

PubMed

Pieper, Kelsey J; Tang, Min; Edwards, Marc A

2017-02-21

Flint, Michigan switched to the Flint River as a temporary drinking water source without implementing corrosion control in April 2014. Ten months later, water samples collected from a Flint residence revealed progressively rising water lead levels (104, 397, and 707 μg/L) coinciding with increasing water discoloration. An intensive follow-up monitoring event at this home investigated patterns of lead release by flow rate-all water samples contained lead above 15 μg/L and several exceeded hazardous waste levels (>5000 μg/L). Forensic evaluation of exhumed service line pipes compared to water contamination "fingerprint" analysis of trace elements, revealed that the immediate cause of the high water lead levels was the destabilization of lead-bearing corrosion rust layers that accumulated over decades on a galvanized iron pipe downstream of a lead pipe. After analysis of blood lead data revealed spiking lead in blood of Flint children in September 2015, a state of emergency was declared and public health interventions (distribution of filters and bottled water) likely averted an even worse exposure event due to rising water lead levels.

Dominant Alcohol-Protein Interaction via Hydration-Enabled Enthalpy-Driven Binding Mechanism

PubMed Central

Chong, Yuan; Kleinhammes, Alfred; Tang, Pei; Xu, Yan; Wu, Yue

2015-01-01

Water plays an important role in weak associations of small drug molecules with proteins. Intense focus has been on binding-induced structural changes in the water network surrounding protein binding sites, especially their contributions to binding thermodynamics. However, water is also tightly coupled to protein conformations and dynamics, and so far little is known about the influence of water-protein interactions on ligand binding. Alcohols are a type of low-affinity drugs, and it remains unclear how water affects alcohol-protein interactions. Here, we present alcohol adsorption isotherms under controlled protein hydration using in-situ NMR detection. As functions of hydration level, Gibbs free energy, enthalpy, and entropy of binding were determined from the temperature dependence of isotherms. Two types of alcohol binding were found. The dominant type is low-affinity nonspecific binding, which is strongly dependent on temperature and the level of hydration. At low hydration levels, this nonspecific binding only occurs above a threshold of alcohol vapor pressure. An increased hydration level reduces this threshold, with it finally disappearing at a hydration level of h~0.2 (g water/g protein), gradually shifting alcohol binding from an entropy-driven to an enthalpy-driven process. Water at charged and polar groups on the protein surface was found to be particularly important in enabling this binding. Although further increase in hydration has smaller effects on the changes of binding enthalpy and entropy, it results in significant negative change in Gibbs free energy due to unmatched enthalpy-entropy compensation. These results show the crucial role of water-protein interplay in alcohol binding. PMID:25856773

Changes in Biofilm Community Structure Associated with Monochloramine-treated Drinking Water Biofilms

EPA Science Inventory

Monochloramine is increasingly used as a drinking water disinfectant because it forms lower levels of traditional disinfectant by-products compared to free-chlorine disinfection treatment. The use of monochloramine has been shown to increase ammonia-oxidizing bacteria and the pr...

Establishment and Early Succession of Bacterial Communities in Monochloramine-Treated Drinking Water Biofilms

EPA Science Inventory

Monochloramine is increasingly used as a drinking water disinfectant because it forms lower levels of regulated disinfection by-products. While its use has been shown to increase nitrifying bacteria, little is known about the bacterial succession within biofilms in monochloramin...

Groundwater and surface-water interactions near White Bear Lake, Minnesota, through 2011

USGS Publications Warehouse

Jones, Perry M.; Trost, Jared J.; Rosenberry, Donald O.; Jackson, P. Ryan; Bode, Jenifer A.; O'Grady, Ryan M.

2013-01-01

The U.S. Geological Survey, in cooperation with the White Bear Lake Conservation District, the Minnesota Pollution Control Agency, the Minnesota Department of Natural Resources, and other State, county, municipal, and regional planning agencies, watershed organizations, and private organizations, conducted a study to characterize groundwater and surface-water interactions near White Bear Lake through 2011. During 2010 and 2011, White Bear Lake and other lakes in the northeastern part of the Twin Cities Metropolitan Area were at historically low levels. Previous periods of lower water levels in White Bear Lake correlate with periods of lower precipitation; however, recent urban expansion and increased pumping from the Prairie du Chien-Jordan aquifer have raised the question of whether a decline in precipitation is the primary cause for the recent water-level decline in White Bear Lake. Understanding and quantifying the amount of groundwater inflow to a lake and water discharge from a lake to aquifers is commonly difficult but is important in the management of lake levels. Three methods were used in the study to assess groundwater and surface-water interactions on White Bear Lake: (1) a historical assessment (1978-2011) of levels in White Bear Lake, local groundwater levels, and their relation to historical precipitation and groundwater withdrawals in the White Bear Lake area; (2) recent (2010-11) hydrologic and water-quality data collected from White Bear Lake, other lakes, and wells; and (3) water-balance assessments for White Bear Lake in March and August 2011. An analysis of covariance between average annual lake-level change and annual precipitation indicated the relation between the two variables was significantly different from 2003 through 2011 compared with 1978 through 2002, requiring an average of 4 more inches of precipitation per year to maintain the lake level. This shift in the linear relation between annual lake-level change and annual precipitation indicated the net effect of the non-precipitation terms on the water balance has changed relative to precipitation. The average amount of precipitation required each year to maintain the lake level has increased from 33 inches per year during 1978-2002 to 37 inches per year during 2003-11. The combination of lower precipitation and an increase in groundwater withdrawals can explain the change in the lake-level response to precipitation. Annual and summer groundwater withdrawals from the Prairie du Chien-Jordan aquifer have more than doubled from 1980 through 2010. Results from a regression model constructed with annual lake-level change, annual precipitation minus evaporation, and annual volume of groundwater withdrawn from the Prairie du Chien-Jordan aquifer indicated groundwater withdrawals had a greater effect than precipitation minus evaporation on water levels in the White Bear Lake area for all years since 2003. The recent (2003-11) decline in White Bear Lake reflects the declining water levels in the Prairie du Chien-Jordan aquifer; increases in groundwater withdrawals from this aquifer are a likely cause for declines in groundwater levels and lake levels. Synoptic, static groundwater-level and lake-level measurements in March/April and August 2011 indicated groundwater was potentially flowing into White Bear Lake from glacial aquifers to the northeast and south, and lake water was potentially discharging from White Bear Lake to the underlying glacial and Prairie du Chien-Jordan aquifers and glacial aquifers to the northwest. Groundwater levels in the Prairie du Chien-Jordan aquifer below White Bear Lake are approximately 0 to 19 feet lower than surface-water levels in the lake, indicating groundwater from the aquifer likely does not flow into White Bear Lake, but lake water may discharge into the aquifer. Groundwater levels from March/April to August 2011 declined more than 10 feet in the Prairie du Chien-Jordan aquifer south of White Bear Lake and to the north in Hugo, Minnesota. Water-quality analyses of pore water from nearshore lake-sediment and well-water samples, seepage-meter measurements, and hydraulic-head differences measured in White Bear Lake also indicated groundwater was potentially flowing into White Bear Lake from shallow glacial aquifers to the east and south. Negative temperature anomalies determined in shallow waters in the water-quality survey conducted in White Bear Lake indicated several shallow-water areas where groundwater may be flowing into the lake from glacial aquifers below the lake. Cool lake-sediment temperatures (less than 18 degrees Celsius) were measured in eight areas along the northeast, east, south, and southwest shores of White Bear Lake, indicating potential areas where groundwater may flow into the lake. Stable isotope analyses of well-water, precipitation, and lake-water samples indicated wells downgradient from White Bear Lake screened in the glacial buried aquifer or open to the Prairie du Chien-Jordan aquifer receive a mixture of surface water and groundwater; the largest surface-water contributions are in wells closer to White Bear Lake. A wide range in oxygen-18/oxygen-16 and deuterium/protium ratios was measured in well-water samples, indicating different sources of water are supplying water to the wells. Well water with oxygen-18/oxygen-16 and deuterium/protium ratios that plot close to the meteoric water line consisted mostly of groundwater because deuterium/protium ratios for most groundwater usually are similar to ratios for rainwater and snow, plotting close to meteoric water lines. Well water with oxygen-18/oxygen-16 and deuterium/protium ratios that plot between the meteoric water line and ratios for the surface-water samples from White Bear Lake consists of a mixture of surface water and groundwater; the percentage of each source varies relative to its ratios. White Bear Lake is the likely source of the surface water to the wells that have a mixture of surface water and groundwater because (1) it is the only large, deep lake near these wells; (2) these wells are near and downgradient from White Bear Lake; and (3) these wells obtain their water from relatively deep depths, and White Bear Lake is the deepest lake in that area. The percentages of surface-water contribution to the three wells screened in the glacial buried aquifer receiving surface water were 16, 48, and 83 percent. The percentages of surface-water contribution ranged from 5 to 79 percent for the five wells open to the Prairie du Chien-Jordan aquifer receiving surface water; wells closest to White Bear Lake had the largest percentages of surface-water contribution. Water-balance analysis of White Bear Lake in March and August 2011 indicated a potential discharge of 2.8 and 4.5 inches per month, respectively, over the area of the lake from the lake to local aquifers. Most of the sediments from a 12.4-foot lake core collected at the deepest part of White Bear Lake consisted of silts, sands, and gravels likely slumped from shallower waters, with a very low amount of low-permeability, organic material.

Hydrology of Cache Valley, Cache County, Utah, and adjacent part of Idaho, with emphasis on simulation of ground-water flow

USGS Publications Warehouse

Kariya, Kim A.; Roark, D. Michael; Hanson, Karen M.

1994-01-01

A hydrologic investigation of Cache Valley was done to better understand the ground-water system in unconsolidated basin-fill deposits and the interaction between ground water and surface water. Ground-water recharge occurs by infiltration of precipitation and unconsumed irrigation water, seepage from canals and streams, and subsurface inflow from adjacent consolidated rock and adjacent unconsolidated basin-fill deposit ground-water systems. Ground-water discharge occurs as seepage to streams and reservoirs, spring discharge, evapotranspiration, and withdrawal from wells.Water levels declined during 1984-90. Less-than-average precipitation during 1987-90 and increased pumping from irrigation and public-supply wells contributed to the declines.A ground-water-flow model was used to simulate flow in the unconsolidated basin-fill deposits. Data primarily from 1969 were used to calibrate the model to steady-state conditions. Transient-state calibration was done by simulating ground-water conditions on a yearly basis for 1982-90.A hypothetical simulation in which the dry conditions of 1990 were continued for 5 years projected an average lO-foot water-level decline between Richmond and Hyrum. When increased pumpage was simulated by adding three well fields, each pumping 10 cubic feet per second, in the Logan, Smithfield, and College Ward areas, water-level declines greater than 10 feet were projected in most of the southeastern part of the valley and discharge from springs and seepage to streams and reservoirs decreased.

Managed aquifer recharge through off-season irrigation in agricultural regions

USGS Publications Warehouse

Niswonger, Richard; Morway, Eric D.; Triana, Enrique; Huntington, Justin L.

2017-01-01

Options for increasing reservoir storage in developed regions are limited and prohibitively expensive. Projected increases in demand call for new long-term water storage to help sustain agriculture, municipalities, industry, and ecological services. Managed aquifer recharge (MAR) is becoming an integral component of water resources around the world. However, MAR faces challenges, including infrastructure costs, difficulty in enhancing recharge, water quality issues, and lack of available water supplies. Here we examine, through simulation modeling of a hypothetical agricultural subbasin in the western U.S., the potential of agricultural managed aquifer recharge (Ag-MAR) via canal seepage and off-season field irrigation. Weather phenomenon in many regions around the world exhibit decadal and other multiyear cycles of extreme precipitation. An ongoing challenge is to develop approaches to store greater amounts of water during these events. Simulations presented herein incorporate Ag-MAR programs and demonstrate that there is potential to enhance regional recharge by 7–13%, increase crop consumptive use by 9–12%, and increase natural vegetation consumption by 20–30%, where larger relative increases occur for lower aquifer hydraulic conductivity and higher specific yield values. Annual increases in groundwater levels were 7 m, and sustained levels following several years of drought were greater than 2 m. Results demonstrate that Ag-MAR has great potential to enhance long-term sustainability of water resources in agricultural basins.

Managed aquifer recharge through off-season irrigation in agricultural regions

NASA Astrophysics Data System (ADS)

Niswonger, Richard G.; Morway, Eric D.; Triana, Enrique; Huntington, Justin L.

2017-08-01

Options for increasing reservoir storage in developed regions are limited and prohibitively expensive. Projected increases in demand call for new long-term water storage to help sustain agriculture, municipalities, industry, and ecological services. Managed aquifer recharge (MAR) is becoming an integral component of water resources around the world. However, MAR faces challenges, including infrastructure costs, difficulty in enhancing recharge, water quality issues, and lack of available water supplies. Here we examine, through simulation modeling of a hypothetical agricultural subbasin in the western U.S., the potential of agricultural managed aquifer recharge (Ag-MAR) via canal seepage and off-season field irrigation. Weather phenomenon in many regions around the world exhibit decadal and other multiyear cycles of extreme precipitation. An ongoing challenge is to develop approaches to store greater amounts of water during these events. Simulations presented herein incorporate Ag-MAR programs and demonstrate that there is potential to enhance regional recharge by 7-13%, increase crop consumptive use by 9-12%, and increase natural vegetation consumption by 20-30%, where larger relative increases occur for lower aquifer hydraulic conductivity and higher specific yield values. Annual increases in groundwater levels were 7 m, and sustained levels following several years of drought were greater than 2 m. Results demonstrate that Ag-MAR has great potential to enhance long-term sustainability of water resources in agricultural basins.

Sustainable-yield estimation for the Sparta Aquifer in Union County, Arkansas

USGS Publications Warehouse

Hays, Phillip D.

2000-01-01

Options for utilizing alternative sources of water to alleviate overdraft from the Sparta aquifer and ensure that the aquifer can continue to provide abundant water of excellent quality for the future are being evaluated by water managers in Union County. Sustainable yield is a critical element in identifying and designing viable water supply alternatives. With sustainable yield defined and a knowledge of total water demand in an area, any unmet demand can be calculated. The ground-water flow model of the Sparta aquifer was used to estimate sustainable yield using an iterative approach. The Sparta aquifer is a confined aquifer of regional importance that comprises a sequence of unconsolidated sand units that are contained within the Sparta Sand. Currently, the rate of withdrawal in some areas greatly exceeds the rate of recharge to the aquifer and considerable water-level declines have occurred. Ground-water flow model results indicate that the aquifer cannot continue to meet growing water-use demands indefinitely and that water levels will drop below the top of the primary producing sand unit in Union County (locally termed the El Dorado sand) by 2008 if current water-use trends continue. Declines of that magnitude will initiate dewatering of the El Dorado sand. The sustainable yield of the aquifer was calculated by targeting a specified minimum acceptable water level within Union County and varying Union County pumpage within the model to achieve the target water level. Selection of the minimum target water level for sustainable-yield estimation was an important criterion for the modeling effort. In keeping with the State Critical Ground-Water Area designation criteria and the desire of water managers in Union County to improve aquifer conditions and bring the area out of the Critical Ground-Water Area designation, the approximate altitude of the top of the Sparta Sand in central Union County was used as the minimum water level target for estimation of sustainable yield in the county. A specific category of sustainable yield? stabilization yield, reflecting the amount of water that the aquifer can provide while maintaining current water levels? also was determined and provides information for short-term management. The top of the primary producing sand unit (the El Dorado sand) was used as the minimum water-level target for estimating stabilization yield in the county because current minimum water levels in central Union County are near the top of the El Dorado sand. Model results show that withdrawals from the Sparta aquifer in Union County must be reduced to 28 percent of 1997 values to achieve sustainable yield and maintain water levels at the top of the Sparta Sand if future pumpage outside of Union County is assumed to increase at the rate observed from 1985-1997. Results of the simulation define a very large current unmet demand and represent a substantial reduction in the county?s current dependence upon the aquifer. If future pumpage outside of Union County is assumed to increase at double the rate observed from 1985-1997, withdrawals from the Sparta aquifer in Union County must be reduced to 25 percent of 1997 values to achieve sustainable yield. Withdrawals from the Sparta aquifer in Union County must be reduced to about 88 to 91 percent (depending on pumpage growth outside of the county) of 1997 values to stabilize water levels at the top of the El Dorado sand. This result shows that 1997 rate of withdrawal in the county is considerably greater than the rate needed to halt the rapid decline in water levels.

The use of an integrated variable fuzzy sets in water resources management

NASA Astrophysics Data System (ADS)

Qiu, Qingtai; Liu, Jia; Li, Chuanzhe; Yu, Xinzhe; Wang, Yang

2018-06-01

Based on the evaluation of the present situation of water resources and the development of water conservancy projects and social economy, optimal allocation of regional water resources presents an increasing need in the water resources management. Meanwhile it is also the most effective way to promote the harmonic relationship between human and water. In view of the own limitations of the traditional evaluations of which always choose a single index model using in optimal allocation of regional water resources, on the basis of the theory of variable fuzzy sets (VFS) and system dynamics (SD), an integrated variable fuzzy sets model (IVFS) is proposed to address dynamically complex problems in regional water resources management in this paper. The model is applied to evaluate the level of the optimal allocation of regional water resources of Zoucheng in China. Results show that the level of allocation schemes of water resources ranging from 2.5 to 3.5, generally showing a trend of lower level. To achieve optimal regional management of water resources, this model conveys a certain degree of accessing water resources management, which prominently improve the authentic assessment of water resources management by using the eigenvector of level H.

Assessment of the Legionnaires' disease outbreak in Flint, Michigan.

PubMed

Zahran, Sammy; McElmurry, Shawn P; Kilgore, Paul E; Mushinski, David; Press, Jack; Love, Nancy G; Sadler, Richard C; Swanson, Michele S

2018-02-20

The 2014-2015 Legionnaires' disease (LD) outbreak in Genesee County, MI, and the outbreak resolution in 2016 coincided with changes in the source of drinking water to Flint's municipal water system. Following the switch in water supply from Detroit to Flint River water, the odds of a Flint resident presenting with LD increased 6.3-fold (95% CI: 2.5, 14.0). This risk subsided following boil water advisories, likely due to residents avoiding water, and returned to historically normal levels with the switch back in water supply. During the crisis, as the concentration of free chlorine in water delivered to Flint residents decreased, their risk of acquiring LD increased. When the average weekly chlorine level in a census tract was <0.5 mg/L or <0.2 mg/L, the odds of an LD case presenting from a Flint neighborhood increased by a factor of 2.9 (95% CI: 1.4, 6.3) or 3.9 (95% CI: 1.8, 8.7), respectively. During the switch, the risk of a Flint neighborhood having a case of LD increased by 80% per 1 mg/L decrease in free chlorine, as calculated from the extensive variation in chlorine observed. In communities adjacent to Flint, the probability of LD occurring increased with the flow of commuters into Flint. Together, the results support the hypothesis that a system-wide proliferation of legionellae was responsible for the LD outbreak in Genesee County, MI.

Association between lifetime exposure to inorganic arsenic in drinking water and coronary heart disease in Colorado residents.

PubMed

James, Katherine A; Byers, Tim; Hokanson, John E; Meliker, Jaymie R; Zerbe, Gary O; Marshall, Julie A

2015-02-01

Chronic diseases, including coronary heart disease (CHD), have been associated with ingestion of drinking water with high levels of inorganic arsenic (> 1,000 μg/L). However, associations have been inconclusive in populations with lower levels (< 100 μg/L) of inorganic arsenic exposure. We conducted a case-cohort study based on individual estimates of lifetime arsenic exposure to examine the relationship between chronic low-level arsenic exposure and risk of CHD. This study included 555 participants with 96 CHD events diagnosed between 1984 and 1998 for which individual lifetime arsenic exposure estimates were determined using data from structured interviews and secondary data sources to determine lifetime residence, which was linked to a geospatial model of arsenic concentrations in drinking water. These lifetime arsenic exposure estimates were correlated with historically collected urinary arsenic concentrations. A Cox proportional-hazards model with time-dependent CHD risk factors was used to assess the association between time-weighted average (TWA) lifetime exposure to low-level inorganic arsenic in drinking water and incident CHD. We estimated a positive association between low-level inorganic arsenic exposure and CHD risk [hazard ratio (HR): = 1.38, 95% CI: 1.09, 1.78] per 15 μg/L while adjusting for age, sex, first-degree family history of CHD, and serum low-density lipoprotein levels. The risk of CHD increased monotonically with increasing TWAs for inorganic arsenic exposure in water relative to < 20 μg/L (HR = 1.2, 95% CI: 0.6, 2.2 for 20-30 μg/L; HR = 2.2; 95% CI: 1.2, 4.0 for 30-45 μg/L; and HR = 3, 95% CI: 1.1, 9.1 for 45-88 μg/L). Lifetime exposure to low-level inorganic arsenic in drinking water was associated with increased risk for CHD in this population.

Trends in the components of extreme water levels signal a rotation of winds in strong storms in the eastern Baltic Sea

NASA Astrophysics Data System (ADS)

Pindsoo, Katri; Soomere, Tarmo

2016-04-01

The water level time series and particularly temporal variations in water level extremes usually do not follow any simple rule. Still, the analysis of linear trends in extreme values of surge levels is a convenient tool to obtain a first approximation of the future projections of the risks associated with coastal floodings. We demonstrate how this tool can be used to extract essential information about concealed changes in the forcing factors of seas and oceans. A specific feature of the Baltic Sea is that sequences of even moderate storms may raise the average sea level by almost 1 m for a few weeks. Such events occur once in a few years. They substantially contribute to the extreme water levels in the eastern Baltic Sea: the most devastating coastal floodings occur when a strong storm from unfortunate direction arrives during such an event. We focus on the separation of subtidal (weekly-scale) processes from those which are caused by a single storm and on establishing how much these two kinds of events have contributed to the increase in the extreme water levels in the eastern Baltic Sea. The analysis relies on numerically reconstructed sea levels produced by the RCO (Rossby Center, Swedish Meteorological and Hydrological Institute) ocean model for 1961-2005. The reaction of sea surface to single storm events is isolated from the local water level time series using a running average over a fixed interval. The distribution of average water levels has an almost Gaussian shape for averaging lengths from a few days to a few months. The residual (total water level minus the average) can be interpreted as a proxy of the local storm surges. Interestingly, for the 8-day average this residual almost exactly follows the exponential distribution. Therefore, for this averaging length the heights of local storm surges reflect an underlying Poisson process. This feature is universal for the entire eastern Baltic Sea coast. The slopes of the exponential distribution for low and high water levels are different, vary markedly along the coast and provide a useful quantification of the vulnerability of single coastal segments with respect to coastal flooding. The formal linear trends in the extreme values of these water level components exhibit radically different spatial variations. The slopes of the trends in the weekly average are almost constant (~4 cm/decade for 8-day running average) along the entire eastern Baltic Sea coast. This first of all indicates that the duration of storm sequences has increased. The trends for maxima of local storm surge heights represent almost the entire spatial variability in the water level extremes. Their slopes are almost zero at the open Baltic Proper coasts of the Western Estonian archipelago. Therefore, an increase in wind speed in strong storms is unlikely in this area. In contrast, the slopes in question reach 5-7 cm/decade in the eastern Gulf of Finland and Gulf of Riga. This feature suggests that wind direction in strongest storms may have rotated in the northern Baltic Sea.

Symbiosis with AMF and leaf Pi supply increases water deficit tolerance of woody species from seasonal dry tropical forest.

PubMed

Frosi, Gabriella; Barros, Vanessa A; Oliveira, Marciel T; Santos, Mariana; Ramos, Diego G; Maia, Leonor C; Santos, Mauro G

2016-12-01

In seasonal dry tropical forests, plants are subjected to severe water deficit, and the arbuscular mycorrhizal fungi (AMF) or inorganic phosphorus supply (P i ) can mitigate the effects of water deficit. This study aimed to assess the physiological performance of Poincianella pyramidalis subjected to water deficit in combination with arbuscular mycorrhizal fungi (AMF) and leaf inorganic phosphorus (P i ) supply. The experiment was conducted in a factorial arrangement of 2 water levels (+H 2 O and -H 2 O), 2 AMF levels (+AMF and -AMF) and 2P i levels (+P i and -P i ). Leaf primary metabolism, dry shoot biomass and leaf mineral nutrients were evaluated. Inoculated AMF plants under well-watered and drought conditions had higher photosynthesis and higher shoot biomass. Under drought, AMF, P i or AMF+P i plants showed metabolic improvements in photosynthesis, leaf biochemistry and higher biomass compared to the plants under water deficit without AMF or P i . After rehydration, those plants submitted to drought with AMF, P i or AMF+P i showed a faster recovery of photosynthesis compared to treatment under water deficit without AMF or P i . However, plants under the drought condition with AMF showed a higher net photosynthesis rate. These findings suggest that AMF, P i or AMF+P i increase the drought tolerance in P. pyramidalis, and AMF associations under well-watered conditions increase shoot biomass and, under drought, promoted faster recovery of photosynthesis. Copyright © 2016 Elsevier GmbH. All rights reserved.

Simulation of salinity intrusion along the Georgia and South Carolina coasts using climate-change scenarios

USGS Publications Warehouse

Conrads, Paul; Roehl, Edwin A.; Daamen, Ruby C.; Cook, John B.

2013-01-01

Potential changes in climate could alter interactions between environmental and societal systems and adversely affect the availability of water resources in many coastal communities. Changes in streamflow patterns in conjunction with sea-level rise may change the salinity-intrusion dynamics of coastal rivers. Several municipal water-supply intakes are located along the Georgia and South Carolina coast that are proximal to the present day saltwater-freshwater interface of tidal rivers. Increases in the extent of salinity intrusion resulting from climate change could threaten the availability of freshwater supplies in the vicinity of these intakes. To effectively manage these supplies, water-resource managers need estimates of potential changes in the frequency, duration, and magnitude of salinity intrusion near their water-supply intakes that may occur as a result of climate change. This study examines potential effects of climate change, including altered streamflow and sea-level rise, on the dynamics of saltwater intrusion near municipal water-supply intakes in two coastal areas. One area consists of the Atlantic Intracoastal Waterway (AIW) and the Waccamaw River near Myrtle Beach along the Grand Strand of the South Carolina Coast, and the second area is on or near the lower Savannah River near Savannah, Georgia. The study evaluated how future sea-level rise and a reduction in streamflows can potentially affect salinity intrusion and threaten municipal water supplies and the biodiversity of freshwater tidal marshes in these two areas. Salinity intrusion occurs as a result of the interaction between three principal forces—streamflow, mean coastal water levels, and tidal range. To analyze and simulate salinity dynamics at critical coastal gaging stations near four municipal water-supply intakes, various data-mining techniques, including artificial neural network (ANN) models, were used to evaluate hourly streamflow, salinity, and coastal water-level data collected over a period exceeding 10 years. The ANN models were trained (calibrated) to learn the specific interactions that cause salinity intrusions, and resulting models were able to accurately simulate historical salinity dynamics in both study areas. Changes in sea level and streamflow quantity and timing can be simulated by the salinity intrusion models to evaluate various climate-change scenarios. The salinity intrusion models for the study areas are deployed in a decision support system to facilitate the use of the models for management decisions by coastal water-resource managers. The report describes the use of the salinity-intrusion models decision support system to evaluate salinity-intrusion dynamics for various climate-change scenarios, including incremental increases in sea level in combination with incremental decreases in streamflow. Operation of municipal water-treatment plants is problematic when the specific-conductance values for source water are greater than 1,000 to 2,000 microsiemens per centimeter (µS/cm). High specific-conductance values contribute to taste problems that require treatment. Data from a gage downstream from a municipal water intake indicate specific conductance exceeded 1,000 µS/cm about 5.4 percent of the time over the 14-year period from August 1995 to August 2008. Simulations of specific conductance at this gaging station that incorporates sea-level rises resulted in a doubling of the exceedances to 11.0 percent for a 1-foot increase and 17.6 percent for a 2-foot increase. The frequency of intrusion of water with specific conductance values of 1,000 µS/cm was less sensitive to incremental reductions in streamflow than to incremental increases in sea level. Simulations of conditions associated with a 10-percent reduction in streamflow, in combination with a 1-foot rise in sea level, increased the percentage of time specific conductance exceeded 1,000 µS/cm at this site from 11.0 to 13.3 percent, and a 20-percent reduction in streamflow increased the percentage of time to 16.6 percent. Precipitation and temperature data from a global circulation model were used, after scale adjustments, as input to a watershed model of the Yadkin-Pee Dee River basin, which flows into the Waccamaw River and Atlantic Intracoastal Waterway study area in South Carolina. The simulated streamflow for historical conditions and projected climate change in the future was used as input for the ANN model in decision support system. Results of simulations incorporating climate-change projections for alterations in streamflow indicate an increase in the frequency of salinity-intrusion events and a shift in the seasonal occurrence of the intrusion events from the summer to the fall.

Groundwater mining of bedrock aquifers in the Denver Basin - Past, present, and future

USGS Publications Warehouse

Moore, J.E.; Raynolds, R.G.; Barkmann, P.E.

2004-01-01

The Denver Basin bedrock aquifer system is an important source of water for municipal and agricultural uses in the Denver and Colorado Springs metropolitan areas. The Denver area is one of the fastest growing areas in the United States with a population of 1.2 million in 1960 that has increased to over 2.4 million by 2000. This rapid population growth has produced a corresponding increase in demand for potable water. Historically, the Denver area has relied on surface water, however, in the past 10 years new housing and recreation developments have begun to rely on groundwater from the bedrock aquifers as the surface water is fully appropriated and in short supply. The Denver Basin bedrock aquifer system consists of Tertiary and Cretaceous age sedimentary rocks known as the Dawson, Denver, Arapahoe and Laramie-Fox Hills Aquifers. The number of bedrock wells has increased from 12,000 in 1985 to 33,700 in 2001 and the withdrawal of groundwater has caused water level declines of 76 m. Water level declines for the past 10 years have ranged from 3 to 12 m per year. The groundwater supplies were once thought to last 100 years but there is concern that the groundwater supplies may be essentially depleted in 10 to 15 years in areas on the west side of the basin. Extensive development of the aquifer system has occurred in the last 25 years especially near the center of the basin in Douglas and El Paso Counties where rapid urban growth continues and surface water is lacking. Groundwater is being mined from the aquifer system because the discharge by wells exceeds the rate of recharge. Concern is mounting that increased groundwater withdrawal will cause water level declines, increased costs to withdraw groundwater, reduced well yield, and reduced groundwater storage. As the long-term sustainability of the groundwater resource is in doubt, water managers believe that the life of the Denver Basin aquifers can be extended with artificial recharge, water reuse, restrictions on lawn watering, well permit restrictions and conservation measures.

Effects of water level on three wetlands soil seed banks on the Tibetan Plateau.

PubMed

Ma, Miaojun; Ma, Zhen; Du, Guozhen

2014-01-01

Although the effect of water level on germination in soil seed banks has been documented in many ecosystems, the mechanism is not fully understood, and to date no empirical studies on this subject exist. Further, no work has been done on the effect of water level on seed banks of drying and saline-alkaline wetlands in alpine areas on the Tibetan Plateau. We examined the effects of water level (0 cm, 5 cm and 10 cm) on seed germination and seedling establishment from soil seed banks at 0-5 cm and 5-10 cm depths in typical, drying, and saline-alkaline wetlands. We also explore the potential role of soil seed bank in restoration of drying and saline-alkaline wetlands. Species richness decreased with increase in water level, but there almost no change in seed density. A huge difference exists in species composition of the seed bank among different water levels in all three wetlands, especially between 0 cm and 5 cm and 0 cm and 10 cm. Similarity of species composition between seed bank and plant community was higher in 0 cm water level in drying wetland than in the other two wetlands. The similarity was much higher in 0 cm water level than in 5 cm and 10 cm water levels in all three wetlands. Species composition of the alpine wetland plant community changed significantly after drying and salinization, however, species composition of the seed bank was unchanged regardless of the environment change. Water level greatly affects seed bank recruitment and plant community establishment. Further, different water levels in restored habitats are likely to determine its species composition of the plant community. The seed bank is important in restoration of degraded wetlands. Successful restoration of drying and salinization wetlands could depend on the seed bank.

Multicausal analysis on water deterioration processes present in a drinking water treatment system.

PubMed

Wang, Li; Ma, Fang; Pang, Changlong; Firdoz, Shaik

2013-03-01

The fluctuation of water turbidity has been studied during summer in the settling tanks of a drinking water treatment plant. Results from the multiple cause-effect model indicated that five main pathways interactively influenced thequalityof tank water. During rain, turbidity levels increased mainly as a result of decreasing pH and anaerobic reactions (partial effect = 68%). Increasing water temperature combined with dissolved oxygen concentration (partial effect = 64%) was the key parameterforcontrolling decreases in water turbidity during nighttime periods after a rainy day. The dominant factor influencing increases in turbidity during sunny daytime periods was algal blooms (partial effect = 86%). However, short-circuiting waves (partial effect = 77%) was the main cause for increased nighttime water turbidity after a sunny day. The trade offbetween regulatory pathways was responsible for environmental changes, and the outcome was determined by the comparative strengths of each pathway.

The use of geoinformatic data and spatial analysis to predict faecal pollution during extreme precipitation events

NASA Astrophysics Data System (ADS)

Ward, Ray; Purnell, Sarah; Ebdon, James; Nnane, Daniel; Taylor, Huw

2013-04-01

The Water Framework Directive (WFD) regulates surface water quality standards in the European Union (EU). The Directive call for the identification and management of point and diffuse sources of pollution and requires the establishment of a 'programme of measures' for identified river basin districts, in order to achieve a "good status" by 2015. The hygienic quality of water is normally monitored using faecal indicator organisms (FIO), such as Escherichia coli, which indicate a potential risk to public health from human waterborne pathogens. Environmental factors influence the transmission of these pathogens and indicator organisms, and statistically significant relationships have been found between rainfall and outbreaks of waterborne disease. Climate change has been predicted to lead to an increase in severe weather events in many parts of Europe, including an increase in the frequency of extreme rainfall events. This in turn is likely to lead to an increase in incidents of human waterborne disease in Europe, unless measures are taken to predict and mitigate for such events. This study investigates a variety of environmental factors that influence the concentration of FIO in surface waters receiving faecal contamination from a variety of sources. Levels of FIO, including Escherichia coli, intestinal enterococci, somatic coliphage and GB124 (a human-specific microbial source tracking marker), were monitored in the Sussex Ouse catchment in Southeast England over a period of 26 months. These data were combined with geoinformatic environmental data within a GIS to map faecal contamination within the river. Previously, precipitation and soil erosion have been identified as major factors that can influence the concentration of these faecal markers, and studies have shown that slope, soil type and vegetation influence both the mechanisms and the rate by which erosion occurs in river catchments. Of the environmental variables studied, extreme precipitation was found to be a major factor contributing to increased levels of FIO. This study identifies areas within the catchment that are likely to demonstrate elevated erosion rates during extreme precipitation events, which are likely to result in raised levels of FIO. The results also demonstrate that increases in the human faecal marker were associated with the discharge points of wastewater treatment works, and that levels of the marker increased whenever the works discharged untreated wastewaters during extreme precipitation. Spatial analysis also highlighted locations where human faecal pollution was present in areas away from wastewater treatment plants, highlighting the potential significance of inputs from septic tanks and other un-sewered domestic wastewater systems. Increases in the frequency of extreme precipitation events in many parts of Europe are likely to result in increased levels of water pollution from both point- and diffuse-sources, increasing the input of pathogens into surface waters, and elevating the health risks to downstream consumers of abstracted drinking water. This study suggests an approach that integrates water microbiology and geoinformatic data to support a 'prediction and prevention' approach, in place of the traditional focus on water quality monitoring. This work may therefore make a significant contribution to future European water resource management and health protection.

The effect of solvent polarity on the accumulation of leachables from pharmaceutical product containers.

PubMed

Jenke, Dennis; Odufu, Alex; Poss, Mitchell

2006-02-01

Material/water equilibrium interaction constants (E(b)) were determined for 12 organic model solutes and a plastic material used in pharmaceutical product containers (non-PVC polyolefin). An excellent correlation was obtained between the measured interaction constants and the organic solute's octanol/water partition coefficient. The effect of solvent polarity on E(b) was assessed by examining the interaction between the plastic and selected model solutes in binary ethanol/water mixtures. In general, logE(b) could be linearily related to the polarity of the ethanol/water mixture. This information, coupled with the interaction model, was used to estimate the levels to which container leachables could accumulate in contacted solutions. Such estimates were made for six known leachables of the polyolefin material and compared to the leachable's measured accumulation levels in binary ethanol/water systems. In general, the accumulation level of the leachables increased with increasing solution polarity. For most of the leachables, the measured accumulation level was less than the calculated levels, suggesting that equilibrium was not achieved in the leaching portion of this study. This lack of equilibrium is attributable to the layered structure of the material studied, as such layering retards the migration of the leachables that are derived from the material's non-solution contact layers.

Molecular dynamics simulations reveal that water diffusion between graphene oxide layers is slow

DOE PAGES

Devanathan, Ram; Chase-Woods, Dylan; Shin, Yongsoon; ...

2016-07-08

Membranes made of stacked layers of graphene oxide (GO) hold the tantalizing promise of revolutionizing desalination and water filtration if selective transport of molecules can be controlled. We present the findings of a molecular dynamics simulation study of water intercalated between GO layers that have a C/O ratio of 4. We simulated a range of hydration levels from 1 wt.% to 23.3 wt.% water. The interlayer spacing increased upon hydration from 0.8 nm to 1.1 nm. We also synthesized GO membranes that showed an increase in spacing from about 0.7 nm to 0.8 nm and an increase in mass ofmore » about 14% on hydration. Water diffusion through GO layers is an order of magnitude slower than that in bulk water, because of strong hydrogen bonded interactions. Most of the water molecules are bound to OH groups even at the highest hydration level. We observed large water clusters that could span graphitic regions, oxidized regions and holes that have been experimentally observed in GO. As a result, slow interlayer diffusion can be consistent with experimentally observed water transport in GO if holes lead to a shorter path length than previously assumed and sorption serves as a key rate-limiting step.« less

Using Value-Focused Thinking to Evaluate the Use of Innovative Stormwater Management Technologies on Air Force Installations

DTIC Science & Technology

2007-03-01

11 Figure 2: Comparison of Water Cycle across Varying Levels of Development...Comparison of Water Cycle across Varying Levels of Development (PWUD, 2006). 2.2.1. Problems Increased volume and flow rate of stormwater runoff...in which the water cycle is undisturbed. The movement of Americans in the later half of the twentieth century from cities to suburbs has resulted

Hydrology of the Sevier-Sigurd ground-water basin and other ground-water basins, central Sevier Valley, Utah.

USGS Publications Warehouse

Lambert, P.M.; Mason, J.L.; Puchta, R.W

1995-01-01

The hydrologic system in the central Sevier Valley, and more specifically the Sevier-Sigurd basin, is a complex system in which surface- and ground-water systems are interrelated. Seepage from an extensive irrigation system is the primary source of recharge to the basin-fill aquifer in the Sevier-Sigurd basin.Water-quality data indicate that inflow from streams and subsurface inflow that intersect evaporite deposits in the Arapien Shale does not adversely affect ground-water quality in the Sevier-Sigurd basin. Stable-isotope data indicate that large sulfate concentrations in water from wells are from the dissolution of gypsum within the basin fill rather than inflow from the Arapien Shale.A ground-water-flow model of the basin-fill aquifer in the Sevier-Sigurd basin was calibrated to steady-state conditions and transient conditions using yearly water-level changes from 1957-88 and monthly water-level changes from 1958-59. Predictive simulations were made to test the effects of reduced recharge from irrigation and increased well discharge. To simulate the effects of conversion from flood to sprinkler irrigation, recharge from irrigated fields was reduced by 50 percent. After twenty years, this reduction resulted in water-level declines of 1 to 8 feet in most of the basin, and a reduction in ground-water discharge to the Sevier River of 4,800 acre-ft/yr. Water-level declines of as much as 12 feet and a reduction in recharge to the Sevier River of 4,800 acre-ft/yr were the result of increasing well discharge near Richfield and Monroe by 25,000 acre-ft/yr. 

Hydrogeology of confined-drift aquifers near the Pomme de Terre and Chippewa rivers, western Minnesota

USGS Publications Warehouse

Delin, G.N.

1986-01-01

A ground-water-flow model indicated that increased pumping from two of the confined aquifers simulated, the Appleton and Benson-middle aquifers, would not adversely affect water levels. The addition of 30 hypothetical wells in the Benson-middle aquifer, pumping a total of approximately 792 million gallons per year, resulted in regional water-level declines of as much as 1.4 and 2.7 feet in the surficial and Benson-middle aquifers, respectively. The addition of 28 hypothetical wells in the Appleton aquifer, pumping a total of approximately 756 million gallons per year, lowered water levels as much as 5 feet in the surficial and Appleton aquifers. Simulations of reduced recharge and increased pumping, which could represent a 3-year drought, probably would lower water levels 2 to 6 feet regionally in the surficial and confined aquifers and as much as 11 feet near aquifer boundaries. Ground-water discharge to the Pomme de Terre and Chippewa Rivers in the southern part of the study area probably would be reduced by approximately 15.2 and 7.4 cubic feet per second, respectively, as a result of the simulated drought. Mean discharge of the Pomme de Terre and Chippewa Rivers is 104 and 267 cubic feet per second, respectively.

Integrated Modeling Approach for Verifying Water Storage Services for a Payment for Environmental Service Programs

NASA Astrophysics Data System (ADS)

Hendricks, G.; Shukla, S.; Guzha, A. C.

2013-12-01

Hydrologic models have been used for improved understanding of how an ecosystem's hydrologic response to human intervention and may provide substantial insight into the viability of payment for environmental services (PES) programs. Little is currently known about how hydrologic models can contribute to the design and evaluation of PES programs. Increased water storage is a desired environmental service (ES) for the Florida Everglades' watershed to reduce nutrient loads and excessive flows to lakes and estuaries in the region. We present monitoring and modeling results to verify the water storage PES for two ranch sites (wetland and watershed scales) located in the Northern Everglades region located north of the Lake Okeechobee (LO). Verification of the water storage PES using at least 3 years of hydrologic data was inconclusive due to variable rainfall during pre- and post-PES periods. An integrated surface and groundwater model, MIKE-SHE/MIKE11, was used to help verify the water storage service as well as predict ecological responses for different water storage scenarios (different levels of storage). The hydrological model was calibrated and validated using field measurements and was able to effectively simulate the surface and groundwater levels for the watershed (Nash Sutcliffe Efficiency, NSE = 0.54 to 0.82) and for surface water levels within wetlands (NSE = 0.54 to 0.84). Scenario analyses for storage levels showed an inverse relationship between board heights for water control structures and flows at the watershed outlet. Changes in flow were marginal when board heights approached a maximum indicating movement of water into subsurface storage. Combining simulation results with field measurements showed reduced flows and increased subsurface storage (2 cm/yr.), a desired outcome for protecting LO and estuarine systems from excessive flows. Simulated wetland water levels were combined with LIDAR-based topography to predict inundation for wetlands at the two PES sites for exploring the addition of biodiversity related ES. Simulations showed that effects of increased storage on enhanced hydro-periods and biodiversity was limited to the wetlands close to the drainage ditches. Results for a variety of water management scenarios showed that modeling can be used as an effective tool for optimizing the ES for a desired PES scheme. Measured and predicted surface flows from watershed and wetland water levels for different scenarios are currently being combined with ecological measurements to develop hydro-ecological models that predict the effects of enhanced water storage on ecological diversity.

Widespread groundwater-level offsets caused by the Mw 5.8 Mineral, Virginia, earthquake of 23 August 2011

USGS Publications Warehouse

Roeloffs, Evelyn A.; Nelms, David L.; Sheets, Rodney A.

2015-01-01

Groundwater levels were offset in bedrock observation wells, measured by the U.S. Geological Survey or others, as far as 553 km from the Mw 5.8 Mineral, Virginia (USA), earthquake on 23 August 2011. Water levels dropped as much as 0.47 m in 34 wells and rose as much as 0.15 m in 12 others. In some wells, which are as much as 213 m deep, the water levels recovered from these deviations in hours to days, but in others the water-level offset may have persisted. The groundwater-level offsets occurred in locations where the earthquake was at least weakly felt, and the maximum water-level excursion increased with felt intensity, independent of epicentral distance. Coseismic static strain from the earthquake was too small and localized to have contributed significantly to the groundwater-level offsets. The relation with intensity is consistent with ground motion from seismic waves leading to the water-level offsets. Examination of the hydrographs indicates that short-period ground motion most likely affected the permeability of the bedrock aquifers monitored by the wells.

Natural and human drivers of salinity in reservoirs and their implications in water supply operation through a Decision Support System

NASA Astrophysics Data System (ADS)

Contreras, Eva; Gómez-Beas, Raquel; Linares-Sáez, Antonio

2016-04-01

Salt can be a problem when is originally in aquifers or when it dissolves in groundwater and comes to the ground surface or flows into streams. The problem increases in lakes hydraulically connected with aquifers affecting water quality. This issue is even more alarming when water resources are used for urban and irrigation supply and water quantity and quality restrict that water demand. This work shows a data based and physical modeling approach in the Guadalhorce reservoir, located in southern Spain. This water body receives salt contribution from mainly groundwater flow, getting salinity values in the reservoir from 3500 to 5500 μScm-1. Moreover, Guadalhorce reservoir is part of a complex system of reservoirs fed from the Guadalhorce River that supplies all urban, irrigation, tourism, energy and ecology water uses, which makes that implementation and validation of methods and tools for smart water management is required. Meteorological, hydrological and water quality data from several monitoring networks and data sources, with both historical and real time data during a 40-years period, were used to analyze the impact salinity. On the other hand, variables that mainly depend on the dam operation, such as reservoir water level and water outflow, were also analyzed to understand how they affect to salinity in depth and time. Finally surface and groundwater inflows to the reservoir were evaluated through a physically based hydrological model to forecast when the major contributions take place. Reservoir water level and surface and groundwater inflows were found to be the main drivers of salinity in the reservoir. When reservoir water level is high, daily water inflow around 0.4 hm3 causes changes in salinity (both drop and rise) up to 500 μScm-1, but no significant changes are found when water level falls 2-3 m. However the gradual water outflows due to dam operation and consequent decrease in reservoir water levels makes that, after dry periods, salinity changes from 3800 to 5100 μScm-1 in the deepest layers are found with a similar daily water inflow. On the other hand, when reservoir water level is low, salinity increases around 1000 μScm-1 are found with a 2 m water level falling. In view of the influence of water level in the reservoir dynamics, this factor should be considered when dam operation decisions are taken by managers in terms of satisfying the water demand. The results will be implemented in a Decision Support System that is being displayed in the Guadalhorce River and which includes prediction of water quantity and quality in the reservoir in terms of salinity, involving water level and water inflow forecasting as the main factors to control the state of the reservoir and therefore with implications in water management. This methodology could be implemented in other reservoirs with high salinity and be adapted to other substances (such as nutrients and heavy metals) associated to water inflow in water bodies where water quality and quantity are driven by human decisions factors besides natural factors such as floods and dynamics of flows in the reservoir.

Private Drinking Water Wells as a Source of Exposure to Perfluorooctanoic Acid (PFOA) in Communities Surrounding a Fluoropolymer Production Facility

PubMed Central

Hoffman, Kate; Webster, Thomas F.; Bartell, Scott M.; Weisskopf, Marc G.; Fletcher, Tony; Vieira, Verónica M.

2011-01-01

Background The C8 Health Project was established in 2005 to collect data on perfluorooctanoic acid (PFOA, or C8) and human health in Ohio and West Virginia communities contaminated by a fluoropolymer production facility. Objective We assessed PFOA exposure via contaminated drinking water in a subset of C8 Health Project participants who drank water from private wells. Methods Participants provided demographic information and residential, occupational, and medical histories. Laboratory analyses were conducted to determine serum-PFOA concentrations. PFOA data were collected from 2001 through 2005 from 62 private drinking water wells. We examined the relationship between drinking water and PFOA levels in serum using robust regression methods. As a comparison with regression models, we used a first-order, single-compartment pharmacokinetic model to estimate the serum:drinking-water concentration ratio at steady state. Results The median serum PFOA concentration in 108 study participants who used private wells was 75.7 μg/L, approximately 20 times greater than the levels in the U.S. general population but similar to those of local residents who drank public water. Each 1 μg/L increase in PFOA levels in drinking water was associated with an increase in serum concentrations of 141.5 μg/L (95% confidence interval, 134.9–148.1). The serum:drinking-water concentration ratio for the steady-state pharmacokinetic model was 114. Conclusions PFOA-contaminated drinking water is a significant contributor to PFOA levels in serum in the study population. Regression methods and pharmacokinetic modeling produced similar estimates of the relationship. PMID:20920951

Water-quality assessment of Francis E Walter reservoir, Luzerne and Carbon counties, Pennsylvania

USGS Publications Warehouse

Barker, J.L.

1983-01-01

Water-quality data, both past and present, show that the waters of the upper Lehigh River basin are somewhat acidic, but otherwise are generally of good quality. This report contains a summary of all known water-quality data collected by the U.S. Geological Survey and other agencies, as well as a synopsis of current water-quality conditions in the reservoir and its tributaries. Water-quality data collected from June 1981 to May 1982 indicate that raising the pool level from 1,300 to approximately 1,392 feet above sea level (NGVD of 1929) has had some significant, if only temporary, detrimental impacts on the reservoir system and its discharge. Depth profile measurements show that, while the impoindment was thermally stratified for only about 2 weeks, the dissolved oxygen concentrations were depressed to levels critical to fishlife throughout much of the reservoir. Another effect of the raised pool was the lowering of pH in the impoinded water. Median pH values were less than 6.0 throughout the reservoir, whereas they commonly exceeded 6.5 at the normal pool elevation. Tests for fecal coliform and fecal streptococcus indicate the impoinded water is nearly free of enteric bacteria. Algal analyses and nutrient concentrations support the premise that the impoundment is nutrient poor and phosphorus limited. Raising the water level an additional 125 feet should have no permanent detrimental effect upon water quality and will greatly increase available habitat for fish and waterflow. Increased retention time should not alter the current trophic status and may decrease the concentration of available nutrients.

Availability of streamflow for recharge of the basal aquifer in the Pearl Harbor area, Hawaii

USGS Publications Warehouse

Hirashima, George Tokusuke

1971-01-01

The Pearl Harbor area is underlain by an extensive basal aquifer that contains large supplies of fresh water. Because of the presence of a cap rock composed of sedimentary material that is less permeable than the basaltic lava of the basal aquifer, seaward movement of ground water is retarded. The cap rock causes the basal water to stand at a high level; thus, the lens of fresh water that floats on sea water is thick. Discharge from the basal ground-water body, which includes pumpage from wells and shafts, averaged 250 million gallons per day during 1931-65. Because the water level in the basal aquifer did not decline progressively, recharge to the ground-water body must have been approximately equal to discharge. Although pumping for agricultural use has decreased since 1931, net ground-water discharge has increased because of a large increase in pumping for urban use. Substitution of ground water for surface water in the irrigation of sugarcane has also contributed to a net increase in ground-water discharge. The development of Mililani Town will further increase discharge. The increase in ground-water discharge may cause an increase in chloride content of the water pumped from wells near the shore of Pearl Harbor unless the increased discharge is balanced by increased recharge to the local aquifer. The aquifer is recharged by direct infiltration and deep percolation of rain, principally in the high forested area, by infiltration and percolation of irrigation water applied in excess of plant requirements, by seepage of water through streambeds, and possibly by ground-water inflow from outside the area. Recharge is greatest in the uplands, where rainfall is heavy and where much infiltration takes place before rainwater collects in the middle and lower reaches of stream channels. Once water collects in and saturates the alluvium of stream channels, additional inflow to the streams will flow out to sea, only slightly decreased by seepage. Average annual direct runoff from the 90-square-mile Pearl Harbor area is 47.27 million gallons per day, or 11.1 inches; this is 13.3 percent of the average annual rainfall (83.3 in.) over the area. Average annual direct runoff in streams at the 800- and 400-foot altitudes is 29 and 38 million gallons per day, respectively. Kipapa Stream has the largest average annual direct runoff at those altitudes--6 and 9 million gallons per day, respectively. Because streams are flashy and have a wide range in discharge, only 60 percent of the average annual runoff can be economically diverted through ditches to recharge areas. The diversion may be increased slightly if reservoirs are used in conjunction with ditches to temporarily detain flows in excess of ditch capacity. The planned irrigation use of some of the perennial flow available in Waikele Stream near sea level will decrease pumping from and increase recharge to the basal aquifer. Suspended-sediment load is mainly silt and clay, and it increases rapidly with increased discharge. Thus, the use of streamflow for artificial recharge poses problems. High flows must be used if recharge is to be effective, but flows must not be so high as to cause clogging of recharge facilities with sediment or woodland debris. Practical tests are needed to determine the advantages and disadvantages of different types of recharge structures, such as a reservoir or basin, large-diameter deep shafts, deep wells, or combinations of all these structures.

Azospirillum and arbuscular mycorrhizal colonization enhance rice growth and physiological traits under well-watered and drought conditions.

PubMed

Ruíz-Sánchez, Michel; Armada, Elisabet; Muñoz, Yaumara; García de Salamone, Inés E; Aroca, Ricardo; Ruíz-Lozano, Juan Manuel; Azcón, Rosario

2011-07-01

The response of rice plants to inoculation with an arbuscular mycorrhizal (AM) fungus, Azospirillum brasilense, or combination of both microorganisms, was assayed under well-watered or drought stress conditions. Water deficit treatment was imposed by reducing the amount of water added, but AM plants, with a significantly higher biomass, received the same amount of water as non-AM plants, with a poor biomass. Thus, the water stress treatment was more severe for AM plants than for non-AM plants. The results showed that AM colonization significantly enhanced rice growth under both water conditions, although the greatest rice development was reached in plants dually inoculated under well-watered conditions. Water level did not affect the efficiency of photosystem II, but both AM and A. brasilense inoculations increased this value. AM colonization increased stomatal conductance, particularly when associated with A. brasilense, which enhanced this parameter by 80% under drought conditions and by 35% under well-watered conditions as compared to single AM plants. Exposure of AM rice to drought stress decreased the high levels of glutathione that AM plants exhibited under well-watered conditions, while drought had no effect on the ascorbate content. The decrease of glutathione content in AM plants under drought stress conditions led to enhance lipid peroxidation. On the other hand, inoculation with the AM fungus itself increased ascorbate and proline as protective compounds to cope with the harmful effects of water limitation. Inoculation with A. brasilense also enhanced ascorbate accumulation, reaching a similar level as in AM plants. These results showed that, in spite of the fact that drought stress imposed by AM treatments was considerably more severe than non-AM treatments, rice plants benefited not only from the AM symbiosis but also from A. brasilense root colonization, regardless of the watering level. However, the beneficial effects of A. brasilense on most of the physiological and biochemical traits of rice plants were only clearly visible when the plants were mycorrhized. This microbial consortium was effective for rice plants as an acceptable and ecofriendly technology to improve plant performance and development. Copyright © 2011 Elsevier GmbH. All rights reserved.

Water levels in major artesian aquifers of the New Jersey Coastal Plain, 1983

USGS Publications Warehouse

Eckel, J.A.; Walker, R.L.

1986-01-01

Water levels and changes in water levels in the major aquifers of the New Jersey Coastal Plain are documented. Water levels in 1,071 wells were measured in 1983, and are compared with 827 water level measurements made in the same wells in 1978. Increased groundwater withdrawals from the major artesian aquifers that underlie the New Jersey Coastal Plain have caused large cones of depression in the artesian heads. These cones are delineated on detailed potentiometric surface maps based on water level data collected in the fall of 1983. Hydrographs from observation wells show trends of water levels for the 6-year period of 1978 through 1983. The Potomac-Raritan-Magothy aquifer system is divided into the lower, middle, and upper aquifers. The potentiometric surfaces in these aquifers form large cones of depression centered in the Camden and Middlesex-Monmouth County areas. Measured water levels declined as much as 23 ft in these areas for the period of study. The lowest levels are 96 ft below sea level in Camden County and 91 ft below sea level in the Middlesex-Monmouth County area. Deep cones of depression in coastal Monmouth and Ocean counties in both the Englishtown aquifer system and Wenonah-Mount Laurel aquifer are similar in location and shape. This is because of an effective hydraulic connection between these aquifers. Measured water levels declined as much as 29 ft in the Englishtown aquifer system and 21 ft in the Wenonah-Mount Laurel aquifer during the period of study. The lowest levels are 249 ft below sea level in the Englishtown aquifer system and 196 ft below sea level in the Wenonah-Mount Laurel aquifer. Water levels in the Piney Point aquifer are as low as 75 ft below sea level at Seaside Park, Ocean County and 35 ft below sea level in southern Cumberland County. Water levels in Cumberland County are affected by large withdrawals of groundwater in Kent County, Delaware. Water levels in the Atlantic City 800 ft sand of the Kirkwood Formation define an extensive elongated cone of depression. Water levels are as low as 76 ft below sea level near Margate and Ventnor, Atlantic County. Measured water levels declined as much as 9 ft in the coastal region between Cape May County and Ocean County for the period of study. (Author 's abstract)

Is fluoride a risk factor for bone cancer? Small area analysis of osteosarcoma and Ewing sarcoma diagnosed among 0–49-year-olds in Great Britain, 1980–2005

PubMed Central

Blakey, Karen; Feltbower, Richard G; Parslow, Roger C; James, Peter W; Gómez Pozo, Basilio; Stiller, Charles; Vincent, Tim J; Norman, Paul; McKinney, Patricia A; Murphy, Michael F; Craft, Alan W; McNally, Richard JQ

2014-01-01

Background: Artificial fluoridation of drinking water to improve dental health has long been a topic of controversy. Opponents of this public health measure have cited the possibility of bone cancer induction. The study objective was to examine whether increased risk of primary bone cancer was associated with living in areas with higher concentrations of fluoride in drinking water. Methods: Case data on osteosarcoma and Ewing sarcoma, diagnosed at ages 0–49 years in Great Britain (GB) (defined here as England, Scotland and Wales) during the period 1980–2005, were obtained from population-based cancer registries. Data on fluoride levels in drinking water in England and Wales were accessed through regional water companies and the Drinking Water Inspectorate. Scottish Water provided data for Scotland. Negative binomial regression was used to examine the relationship between incidence rates and level of fluoride in drinking water at small area level. Results: The study analysed 2566 osteosarcoma and 1650 Ewing sarcoma cases. There was no evidence of an association between osteosarcoma risk and fluoride in drinking water [relative risk (RR) per one part per million increase in the level of fluoride = 1·001; 90% confidence interval (CI) 0·871, 1·151] and similarly there was no association for Ewing sarcoma (RR = 0·929; 90% CI 0·773, 1·115). Conclusions: The findings from this study provide no evidence that higher levels of fluoride (whether natural or artificial) in drinking water in GB lead to greater risk of either osteosarcoma or Ewing sarcoma. PMID:24425828

Estimating salinity intrusion effects due to climate change on the Lower Savannah River Estuary

USGS Publications Warehouse

Conrads, Paul; Roehl, Edwin A.; Daamen, Ruby C.; Cook, John B.; Sexton, Charles T.; Tufford, Daniel L.; Carbone, Gregory J.; Dow, Kristin

2010-01-01

The ability of water-resource managers to adapt to future climatic change is especially challenging in coastal regions of the world. The East Coast of the United States falls into this category given the high number of people living along the Atlantic seaboard and the added strain on resources as populations continue to increase, particularly in the Southeast. Increased temperatures, changes in regional precipitation regimes, and potential increased sea level may have a great impact on existing hydrological systems in the region. The Savannah River originates at the confluence of the Seneca and Tugaloo Rivers, near Hartwell, Ga., and forms the state boundary between South Carolina and Georgia. The J. Strom Thurmond Dam and Lake, located 238 miles upstream from the Atlantic Ocean, is responsible for most of the flow regulation that affects the Savannah River from Augusta, Ga., to the coast. The Savannah Harbor experiences semi-diurnal tides of two low and two high tides in a 24.8-hour period with pronounced differences in tidal range between neap and spring tides occurring on a 14-day and 28-day lunar cycle. Salinity intrusion results from the interaction of three principal forces - streamflow, mean tidal water levels, and tidal range. To analyze, model, and simulate hydrodynamic behaviors at critical coastal streamgages in the Lower Savannah River Estuary, data-mining techniques were applied to over 15 years of hourly streamflow, coastal water-quality, and water-level data. Artificial neural network (ANN) models were trained to learn the variable interactions that cause salinity intrusions. Streamflow data from the 9,850 square-mile Savannah River Basin were input into the model as time-delayed variables. Tidal inputs to the models were obtained by decomposing tidal water-level data into a “periodic” signal of tidal range and a “chaotic” signal of mean water levels. The ANN models were able to convincingly reproduce historical behaviors and generate alternative scenarios of interest. Important freshwater resources are located proximal to the freshwater-saltwater interface of the estuary. The Savannah National Wildlife Refuge is located in the upper portion of the Savannah River Estuary. The tidal freshwater marsh is an essential part of the 28,000-acre refuge and is home to a diverse variety of wildlife and plant communities. Two municipal freshwater intakes are located upstream from the refuge. To evaluate the impact of climate change on salinity intrusion on these resources, inputs of streamflows and mean tidal water levels were modified to incorporate estimated changes in precipitation patterns and sea-level rise appropriate for the Southeastern United States. Changes in mean tidal water levels were changed parametrically for various sea-level rise conditions. Preliminary model results at the U.S. Geological Survey (USGS) Interstate-95 streamgage (station 02198840) for a 7½-year simulation show that historical daily salinity concentrations never exceeded 0.5 practical salinity units (psu). A 1-foot sea-level rise (ft, 30.5 centimeters [cm]) would increase the number of days of salinity concentrations greater than 0.5 psu to 47 days. A 2-ft (61 cm) sea-level rise would increase the number of days to 248.

Water resources during drought conditions and postfire water quality in the upper Rio Hondo Basin, Lincoln County, New Mexico, 2010-13

USGS Publications Warehouse

Sherson, Lauren R.; Rice, Steven E.

2015-07-16

Changes in climate and increased groundwater and surface-water use are likely to affect the availability of water in the upper Rio Hondo Basin. Increased drought probably will increase the potential for wildfires, which can affect downstream water quality and increase flood potential. Climate-research predicted decreases in winter precipitation may have an adverse effect on the amount of groundwater recharge that occurs in the upper Rio Hondo Basin, given the predominance of winter precipitation recharge as indicated by the stable isotope results. Decreases in surface-water supplies because of persistent drought conditions and reductions in the quality of water because of the effects of wildfire may lead to a larger reliance on groundwater reserves in the upper Rio Hondo Basin. Decreasing water levels because of increasing groundwater withdrawal could reduce base flows in the Rio Bonito and Rio Ruidoso. Well organized and scientifically supported regional water-resources management will be necessary for dealing with the likely scenario of increases in demand coupled with decreases in supply in the upper Rio Hondo Basin.

Evaluation of Handheld Assays for the Detection of Ricin and Staphylococcal Enterotoxin B in Disinfected Waters

PubMed Central

Wade, Mary Margaret; Biggs, Tracey D.; Insalaco, Joseph M.; Neuendorff, Lisa K.; Bevilacqua, Vicky L. H.; Schenning, Amanda M.; Reilly, Lisa M.; Shah, Saumil S.; Conley, Edward K.; Emanuel, Peter A.; Zulich, Alan W.

2011-01-01

Development of a rapid field test is needed capable of determining if field supplies of water are safe to drink by the warfighter during a military operation. The present study sought to assess the effectiveness of handheld assays (HHAs) in detecting ricin and Staphylococcal Enterotoxin B (SEB) in water. Performance of HHAs was evaluated in formulated tap water with and without chlorine, reverse osmosis water (RO) with chlorine, and RO with bromine. Each matrix was prepared, spiked with ricin or SEB at multiple concentrations, and then loaded onto HHAs. HHAs were allowed to develop and then read visually. Limits of detection (LOD) were determined for all HHAs in each water type. Both ricin and SEB were detected by HHAs in formulated tap water at or below the suggested health effect levels of 455 ng/mL and 4.55 ng/mL, respectively. However, in brominated or chlorinated waters, LODs for SEB increased to approximately 2,500 ng/mL. LODs for ricin increased in chlorinated water, but still remained below the suggested health effect level. In brominated water, the LOD for ricin increased to approximately 2,500 ng/mL. In conclusion, the HHAs tested were less effective at detecting ricin and SEB in disinfected water, as currently configured. PMID:21792355

Evaluating the response of Lake Prespa (SW Balkan) to future climate change projections from a high-resolution model

NASA Astrophysics Data System (ADS)

van der Schriek, Tim; Varotsos, Konstantinos V.; Giannakopoulos, Christos

2017-04-01

The Mediterranean stands out globally due to its sensitivity to (future) climate change. Projections suggest that the Balkans will experience precipitation and runoff decreases of up to 30% by 2100. However, these projections show large regional spatial variability. Mediterranean lake-wetland systems are particularly threatened by projected climate changes that compound increasingly intensive human impacts (e.g. water extraction, drainage, pollution and dam-building). Protecting the remaining systems is extremely important for supporting global biodiversity. This protection should be based on a clear understanding of individual lake-wetland hydrological responses to future climate changes, which requires fine-resolution projections and a good understanding of the impact of hydro-climate variability on individual lakes. Climate change may directly affect lake level (variability), volume and water temperatures. In turn, these variables influence lake-ecology, habitats and water quality. Land-use intensification and water abstraction multiply these climate-driven changes. To date, there are no projections of future water level and -temperature of individual Mediterranean lakes under future climate scenarios. These are, however, of crucial importance to steer preservation strategies on the relevant catchment-scale. Here we present the first projections of water level and -temperature of the Prespa Lakes covering the period 2071-2100. These lakes are of global significance for biodiversity, and of great regional socio-economic importance as a water resource and tourist attraction. Impact projections are assessed by the Regional Climate Model RCA4 of the Swedish Meteorological and Hydrological Institute (SMHI) driven by the Max Planck Institute for Meteorology global climate model MPI-ESM-LR under two RCP future emissions scenarios, the RCP4.5 and the RCP8.5, with the simulations carried out in the framework of EURO-CORDEX. Temperature, evapo(transpi)ration and precipitation over the Prespa catchment were simulated with this high horizontal resolution (12 × 12 km) regional climate model. Lake temperatures were derived from surface temperatures based on physical models, while water levels were calculated with the lake water balance model. Climate simulations indicate that annual- and wet season catchment precipitation does not significantly change by the end of the century. The median precipitation decreases, while precipitation variability increases. The percentage of annual precipitation falling in the wet season increases by 5-10%, indicating a stronger seasonality in the precipitation regime. Summer (lake) temperatures and lake surface evaporation will rise significantly under both explored climate change scenarios. Lake impact projections indicate that evaporation changes will cause the water level of Lake Megali Prespa to fall by 5m to 840-839m. The increased precipitation variability will cause large inter-annual water level fluctuations. Average water level may fall even further if: (1) drier summers lead to more water abstraction for irrigation, and (2) there is a reduction in winter snowfall/accumulation and thus less discharge. These findings are of key importance for developing sustainable lake water resource management in a region that is highly vulnerable to future climate change and already experiences significant water stress. Research paves the way for innovative management adaptation strategies focussed on decreasing water abstraction, for example through introducing smart irrigation and selecting more water efficient crops.

Effects of Irrigation, Drought, and Ground-Water Withdrawals on Ground-Water Levels in the Southern Lihue Basin, Kauai, Hawaii

USGS Publications Warehouse

Izuka, Scot K.

2006-01-01

A numerical ground-water-flow model was used to investigate the effects of irrigation on ground-water levels in the southern Lihue Basin, Kauai, Hawaii, and the relation between declining ground-water levels observed in the basin in the 1990s and early 2000s and concurrent drought, irrigation reduction, and changes in ground-water withdrawal. Results of steady-state model simulations indicate that changing from pre-development to 1981 irrigation and ground-water-withdrawal conditions could, given enough time for steady state to be achieved, raise ground-water levels in some areas of the southern Lihue Basin by as much as 200 feet, and that changing from 1981 to 1998 irrigation and ground-water-withdrawal conditions could lower ground-water levels in some areas by as much as 100 feet. Transient simulations combining drought, irrigation reduction, and changes in ground-water withdrawal show trends that correspond with those observed in measured water levels. Results of this study indicate that irrigation reduction was the primary cause of the observed decline in ground-water-levels. In contrast, ground-water withdrawal had a long-duration but small-magnitude effect, and drought had a widespread, high-magnitude but short-duration effect. Inasmuch as irrigation in the future is unlikely to return to the same levels as during the period of peak sugarcane agriculture, the decline in ground-water levels resulting from the reduction and ultimate end of sugarcane irrigation can be considered permanent. Assuming that irrigation does not return to the southern Lihue Basin and that, on average, normal rainfall persists and ground-water withdrawal remains at 1998 rates, model projections indicate that average ground-water levels in the Kilohana-Puhi area will continue to recover from the drought of 1998-2002 and eventually rise to within about 4 feet of the pre-drought conditions. Long-term climate trends, increases in ground-water withdrawal, or other factors not simulated in the model could also affect ground-water levels in the southern Lihue Basin in the future.

Hydraulic analysis of Chenango River, Broome County, New York in relation to state highway plan

USGS Publications Warehouse

Dunn, Bernard

1981-01-01

Hydraulic analyses of the 50- and 100-year floods in a 3.2 mile reach of the Chenango River in the towns of Fenton and Chenango in New York were made to determine the effects of two alternative bridge designs on flood levels. Neither design would cause more than a 0.1-foot increase in water level of the 50-year flood nor more than a 0.2-foot increase in water level of the 100-year flood above levels that would occur during these floods under present channel conditions. The discharges used in the analyses were 55,200 cubic feet per second for the 50-year flood and 63,000 cubic feet per second for the 100-year flood. Mean flow velocities and water-surface elevations at 17 cross sections are given for both bridge designs and are compared with those that would occur under present conditions. (USGS)

[Succession of Larix olgensis and Betula platyphlla-marsh ecotone communities in Changbai Mountain].

PubMed

Mu, Changcheng

2003-11-01

The succession of communities within the ecotone between forest and marsh in Changbai Mountain was studied to identify the interrelation between the succession of ecotone communities and the mesophytization of the ecotone. The succession regime of the ecotone communities was studies by patch size (the volume of each mound) and age class of different tree species, water transmission from soil to atmosphere through the transpiration of different tree species, and regional climate warming and community succession. The results demonstrated that both patch size and water loss through transpiration were increased with age class. The increased volume of mounds and water loss through transpiration of trees were converted to the raised ground surface level and the lowered ground surface water level. Within 60 years, the ground surface level would be raised by 0.405-0.590 m, depending on the distance to the marsh, and the aboveground water level would be lowered by 1.050-1.442 m. Climate had a great effect on the community dynamics. Community succession and regional climate warming intensified the mesophytization process of forest-marsh ecotone, and the ecotone communities would eventually change into forest communities within a relatively short period.

Hydrogeology of the Faultless site, Nye County, Nevada

DOE Office of Scientific and Technical Information (OSTI.GOV)

Thordarson, W.

The Faultless event was the detonation of an intermediate-yield nuclear device on January 19, 1968, at a depth of 975 m below the surface of Hot Creek Valley, Nevada. This report presents details of the hydrogeology of the rubble chimney and radiochemical monitoring in re-entry hole UC-1-P-2SR. The surface location of re-entry hole UC-1-P-2SR is about 91 m north of the emplacement hole, UC-1. Re-entry hole UC-1-P-2SR was drilled to a total depth of about 1097 m. The hole penetrated Quaternary and Tertiary valley-fill sediments above the rubble chimney, as well as Quaternary and Tertiary valley-fill and Tertiary tuffaceous sedimentsmore » within the chimney and rubble-filled cavity. Monitoring of the water level in re-entry hole UC-1-P-2SR indicated that, from 1970 to 1974, the water level was 695 m below land surface. During filling of the rubble chimney from 1974 to 1983, the water level rose slowly to a depth of 335.1 m. The 1983 level was about 167 m below the pre-event level that was about 168 m below land surface. Water with temperatures ranging from 37 to 61/sup 0/C occurred at the bottom of the re-entry hole at depths ranging from 728 to 801 m. A temperature of 100/sup 0/C at a depth of 820 m was projected from temperature logs. The hydraulic connection between the re-entry hole and the rubble chimney is considered poor to fair. Chemical analyses of water samples indicate that the water predominantly was a sodium bicarbonate type. Chemical and radiochemical analyses indicated that, although the constituents generally increased with increasing depth, three distinct water-quality zones have lasted for more than 16 years, even during the rising water level. The hot, radioactive water from the Faultless event apparently rose into the lower zone concomitant with the rising water level, as the rubble chimney was being filled. This general rise was interrupted by the apparently major dilution from colder water descending from the upper zone during 1975 and 1977.« less

Quantification of umu genotoxicity level of urban river water.

PubMed

Kameya, T; Nagato, T; Nakagawa, K; Yamashita, D; Kobayashi, T; Fujie, K

2011-01-01

In recent years, the request of environmental safety management for carcinogenic substances, mutagenic substances and/or reproductive toxicity substances (CMR) has increased. This study focused on clarifying the genotoxicity level of environmental water and its release source by using the umu test provided in ISO13829. Although a genotoxicity index "induction ratio (IR)" is used in ISO13829, we normalised it to make it possible to compare various environmental water quantitatively to each other as a new index "genotoxic activity (GA=(IR-1)/Dose)". Sample water was collected and concentrated to 100 times or 1,000 times by a solid phase extraction method. As the test results, it was found that GA level in actual river water varied widely from less than the determination limit of 23 [1/L] to 1,100 [1/L] by quantitative comparison, and the value was also equivalent to more than 50 times the level of tap water. The GA level of household wastewater was not so high, but the levels of treated water from wastewater treatment plant (WTP) were from 220 [1/L] to 3,200 [1/L]. Raw sewage of some WTP shows high level genotoxicity. A part of genotoxicity substances, for example 50%, could be removed by conventional wastewater treatment, but it was not enough to reduce the water environmental load of genotoxicity.

SPECIES-SPECIFIC PARTITIONING OF SOIL WATER RESOURCES IN AN OLD-GROWTH DOUGLAS-FIR/WESTERN HEMLOCK FOREST

EPA Science Inventory

Although tree- and stand-level estimates of forest water use are increasingly common, relatively little is known about partitioning of soil water resources among co-occurring tree species. We studied seasonal courses of soil water utilization in a 450-year-old Pseudotsuga menzies...

Impacts of Vegetation Change on the Water Balance of Superficial, Coastal Aquifers: a Comparative Study of Pre-clearing and Post-clearing Recharge Under Native Vegetation, and Pine Plantations

NASA Astrophysics Data System (ADS)

Bekele, E. B.; Salama, R. B.

2003-12-01

Replacing native vegetation with pasture across the northern Perth Basin in Western Australia has profoundly altered the water balance and led to dramatic increases in recharge and groundwater levels from about the mid-1960's, whereas replacing native vegetation with pine plantations and market gardens further south in the Gnangara groundwater Mound together with declining rainfall has caused continuous declines in recharge and water levels. Long-term monitoring of water levels in the Parmelia Formation, a superficial, semi-confined aquifer of predominantly weathered sand in the northern Perth Basin, indicates maximum rates of water level rise on the order of 40 to 55 cm/yr within the past decade. In the Gnangara Mound, water levels are falling by 10 to 20 cm/yr in the unconfined aquifer. Quantifying groundwater capture due to the removal of native vegetation is crucial for predicting the extent of groundwater development in the northern Perth Basin, whereas in the Gnangara Mound, it is necessary to limit the total water use to the declining resource to arrest the trend in falling water levels. Estimates of groundwater recharge before the removal of native vegetation in the northern Perth Basin determined from chloride tracer measurements in the soil water beneath native bushland and from groundwater samples ranged from 12 to 16 mm/yr, while estimates from soil water flux at the water table are approximately 5 mm/yr. In contrast, recharge estimates under cleared conditions since 1970 are between 24 and 50 mm/yr, based on hydrograph analyses of different bores. CFC and chloride analyses of water sampled from piezometers screened at the water table gave recharge estimates of 20 to 30 mm/yr and less than 10 mm/yr, respectively. In the Gnangara Mound recharge varies between 70 to 200 mm/year; the lowest recharge values were under the pines and the highest in the urban areas. Due to increasing demand on the groundwater resources and the declining water levels, additional resources can be provided only by removing the pine plantations, proper management of the Banksia woodland areas and capture of fresh groundwater discharging to the sea.

Hydrology and trout populations of cold-water rivers of Michigan and Wisconsin

USGS Publications Warehouse

Hendrickson, G.E.; Knutilla, R.L.

1974-01-01

Statistical multiple-regression analyses showed significant relationships between trout populations and hydrologic parameters. Parameters showing the higher levels of significance were temperature, hardness of water, percentage of gravel bottom, percentage of bottom vegetation, variability of streamflow, and discharge per unit drainage area. Trout populations increase with lower levels of annual maximum water temperatures, with increase in water hardness, and with increase in percentage of gravel and bottom vegetation. Trout populations also increase with decrease in variability of streamflow, and with increase in discharge per unit drainage area. Most hydrologic parameters were significant when evaluated collectively, but no parameter, by itself, showed a high degree of correlation with trout populations in regression analyses that included all the streams sampled. Regression analyses of stream segments that were restricted to certain limits of hardness, temperature, or percentage of gravel bottom showed improvements in correlation. Analyses of trout populations, in pounds per acre and pounds per mile and hydrologic parameters resulted in regression equations from which trout populations could be estimated with standard errors of 89 and 84 per cent, respectively.

Groundwater geochemistry in shallow aquifers above longwall mines in Illinois, USA

NASA Astrophysics Data System (ADS)

Booth, C. J.; Bertsch, L. P.

1999-12-01

Aquifers above high-extraction underground coal mines are not affected by mine drainage, but they may still exhibit changes in groundwater chemistry due to alterations in groundwater flow induced by mine subsidence. At two active longwall mine sites in Illinois, USA, glacial-drift aquifers were largely unaffected by mining, but the geochemistry of the bedrock aquifers changed during the post-mining water-level recovery. At the Jefferson site, brackish, high-sulfate water present in the upper bedrock shale briefly had lower values of total dissolved solids (TDS) after mining due to increased recharge from the overlying drift, whereas TDS and sulfate increased in the sodium-bicarbonate water present in the underlying sandstone due to downward leakage from the shale and lateral inflow of water through the sandstone. At the Saline site, sandstones contained water ranging from brackish sodium-chloride to fresh sodium-bicarbonate type. Post-mining recovery of the potentiometric levels was minimal, and the water had minor quality changes. Longwall mining affects geochemistry due to subsidence-related fracturing, which increases downward leakage from overlying units, and due to the temporary potentiometric depression and subsequent recovery, whereby water from surrounding areas of the aquifer recharges the affected zone above and adjacent to the mine.

Evaluation of water levels in major aquifers of the New Jersey coastal plain, 1978

USGS Publications Warehouse

Walker, R.L.

1983-01-01

Increased withdrawals from the major artesian aquifers that underlie the New Jersey Coastal Plain have caused water-level declines and large regional cones of depression. These cones of depression are delineated on detailed potentiometric surface maps produced from water-level data collected in the field in 1978. Water levels for 1978 are compared with those from 1970 or 1973, and water-level changes are evaluated and compared with hydrographs from observation wells. The Potomac-Raritan-Magothy aquifer system is divided into regionally extensive lower and upper aquifers. These aquifers have large cones of depression centered in Camden, Middlesex, and Monmouth Counties. Water levels declined 5 to 20 feet in these areas between 1973 and 1978. Deep cones of depression in coastal Monmouth and Ocean Counties in the Englishtown and Wenonah-Mount Laurel aquifers are similar in location and shape, due to a good hydraulic connection between these aquifers. Water levels declined 2 to 31 feet in the Englishtown aquifer and 12 to 26 feet in the Wenonah-Mount Laurel aquifer between 1973 and 1978. Water levels in the Atlantic City 800-foot sand of the Kirkwood Formation define an extensive elongated cone of depression centered near Margate, Atlantic County. Head changes ranged from a decline of 4 feet to a recovery of 9 feet during 1970-78. The lowest heads in the Cohansey Sand were about 26 feet below sea level at Cape May, Cape May County, and less than 0.5 miles from salty ground water. (USGS)

Freeze-drying of tert-butyl alcohol/water cosolvent systems: effects of formulation and process variables on residual solvents.

PubMed

Wittaya-Areekul, S; Nail, S L

1998-04-01

The objective of this study was to identify significant formulation and processing variables affecting levels of tert-butyl alcohol (TBA) and isopropyl alcohol (IPA) in freeze-dried solids prepared from TBA/water cosolvent systems. The variables examined were the physical state of the solute (crystalline vs amorphous), initial TBA concentration, freezing rate, cake thickness, and the temperature and duration of secondary drying. Sucrose and glycine were used as models for noncrystallizing and crystallizing solutes, respectively. The TBA concentration above which eutectic crystallization takes place was determined by differential scanning calorimetry. Model formulations were subjected to extremes of freezing rate by either dipping in liquid nitrogen or by slowly freezing on the shelf of a freeze-dryer. Dynamics of solvent loss during secondary drying was determined by withdrawing samples as a function of time at different shelf temperatures using a thief system. On the basis of these studies, the most important determinant of residual TBA level is the physical state of the solute. Freeze-dried glycine contained very low levels of residual TBA (0.01-0.03%) regardless of freezing rate or initial TBA concentration. For freeze-dried sucrose, residual TBA levels were approximately 2 orders of magnitude higher and were significantly affected by initial TBA concentration and freezing rate. For the sucrose/TBA/water system, relatively low residual TBA levels were obtained when the initial TBA level was above the threshold concentration for eutectic crystallization of TBA, whereas samples freeze-dried from solutions containing TBA concentrations below this threshold contained significantly higher levels of TBA. Residual IPA levels increased continuously with initial concentration of TBA in the sucrose/TBA/water system. Formulations of sucrose/TBA/water which were frozen rapidly contained residual TBA levels which were approximately twice those measured in the same formulation after slow freezing and drying under the same conditions. For the sucrose/TBA/water system, the temperature and time of secondary drying had only minimal influence on residual TBA in the freeze-dried solid. At low initial TBA concentrations (2%), residual TBA increases with increased cake thickness, perhaps because of the influence of depth of fill on effective freezing rate.

Environmental controls on sap flow in a northern hardwood forest.

PubMed

Bovard, B D; Curtis, P S; Vogel, C S; Su, H-B; Schmid, H P

2005-01-01

Our objective was to gain a detailed understanding of how photosynthetically active radiation (PAR), vapor pressure deficit (D) and soil water interact to control transpiration in the dominant canopy species of a mixed hardwood forest in northern Lower Michigan. An improved understanding of how these environmental factors affect whole-tree water use in unmanaged ecosystems is necessary in assessing the consequences of climate change on the terrestrial water cycle. We used continuously heated sap flow sensors to measure transpiration in mature trees of four species during two successive drought events. The measurements were scaled to the stand level for comparison with eddy covariance estimates of ecosystem water flux (Fw). Photosynthetically active radiation and D together explained 82% of the daytime hourly variation in plot-level transpiration, and low soil water content generally resulted in increased stomatal sensitivity to increasing D. There were also species-specific responses to drought. Quercus rubra L. showed low water use during both dry and wet conditions, and during periods of high D. Among the study species, Acer rubrum L. showed the greatest degree of stomatal closure in response to low soil water availability. Moderate increases in stomatal sensitivity to D during dry periods were observed in Populus grandidentata Michx. and Betula papyrifera Marsh. Sap flow scaled to the plot level and Fw demonstrated similar temporal patterns of water loss suggesting that the mechanisms controlling sap flow of an individual tree also control ecosystem evapotranspiration. However, the absolute magnitude of scaled sap flow estimates was consistently lower than Fw. We conclude that species-specific responses to PAR, D and soil water content are key elements to understanding current and future water fluxes in this ecosystem.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Koo, Ja-Kong; Do, Nam-Young

The K site near Seoul began landfilling in 1992. The landfilled wastes include municipal solid waste (66.4%), construction residues (20.4%), water and wastewater sludges (trace levels), and hazardous waste (trace levels). The water content of the municipal solid waste is very high (47.3%); as a result, the leachate level (average E.L.) of the landfill, the design value of which is 7.0 m, was measured at 10.3 m in January 1995 and is increasing. The increase of leachate level in the landfill site causes a problem with slope stability. The leachate level at each disposal stage divided by the intermediate covermore » layer was calculated with the HELP (Hydrologic Evaluation of Landfill Performance) model and calibrated with the data measured from February 1993 to June 1995. Also, the hydraulic conductivities of the waste layer and the intermediate cover layer in each stage were calibrated continuously with HELP model analysis. To verify these results, the total water balance in the landfill site was calculated using the infiltration rate calculated from HELP modeling. The leachate level was E.L. 10.0 m, which was close to the measured leachate level. To estimate the change of the leachate level in the future, the total water balances with different leachate discharge rates of 3,000, 3,500, and 5,000 m{sup 3}/day were analyzed. When the leachate discharge rate was 5,000 ton/day and the initial water content was decreased below 25%, the average leachate level was 10.8 m. This result satisfies the safety factor requirements (=1.3) for landfill slope stability. 4 refs., 8 figs., 1 tab.« less

Ground-water, surface-water, and water-chemistry data, Black Mesa area, northeastern Arizona--2004-05

USGS Publications Warehouse

Truini, Margot; Macy, J.P.

2006-01-01

The N aquifer is the major source of water in the 5,400-square-mile area of Black Mesa in northeastern Arizona. Availability of water is an important issue in this area because of continued industrial and municipal use, a growing population, and precipitation of about 6 to 14 inches per year. The monitoring program in the Black Mesa area has been operating since 1971 and is designed to determine the long-term effects of ground-water withdrawals from the N aquifer for industrial and municipal uses. The monitoring program includes measurements of (1) ground-water pumping, (2) ground-water levels, (3) spring discharge, (4) surface-water discharge, (5) ground-water chemistry, and (6) periodic testing of ground-water withdrawal meters. In 2004, total ground-water withdrawals were 7,210 acre-feet, industrial withdrawals were 4,370 acre-feet, and municipal withdrawals were 2,840 acre-feet. From 2003 to 2004, total withdrawals decreased by less than 1 percent, industrial withdrawals decreased by 2 percent, and municipal withdrawals increased by 2 percent. From 2004 to 2005, annually measured water levels declined in 6 of 13 wells in the unconfined areas of the aquifer, and the median change was -0.1 foot. Water levels declined in 8 of 12 wells in the confined area of the aquifer, and the median change was -1.2 feet. From the prestress period (prior to 1965) to 2005, the median water-level change for 33 wells was -9.0 feet. Median water-level changes were -0.6 foot for 16 wells in the unconfined areas and -32.0 feet for 17 wells in the confined area. Discharges were measured once in 2004 and once in 2005 at four springs. Discharge increased by 8 percent at Pasture Canyon Spring, decreased by 5 percent at Moenkopi School Spring, increased by 71 percent at an unnamed spring near Dennehotso, and stayed the same at Burro Spring. For the period of record at each spring, discharges from the four springs have fluctuated; however, an increasing or decreasing trend is not apparent. Continuous records of surface-water discharge have been collected from 1976 to 2004 at Moenkopi Wash, 1996 to 2004 at Laguna Creek, 1993 to 2004 at Dinnebito Wash, 1994 to 2004 at Polacca Wash, and August 2004 to December 2004 at Pasture Canyon Spring. Median flows for November, December, January, and February of each water year were used as an index of ground-water discharge to those streams. Since 1995, the median winter flows have decreased for Moenkopi Wash, Dinnebito Wash, and Polacca Wash. Since the first continuous record of surface-water discharge in 1997, there is no consistent trend in the median winter flow for Laguna Creek. In 2005, water samples were collected from 11 wells and 4 springs and analyzed for selected chemical constituents. Dissolved-solids concentrations ranged from 122 to 639 milligrams per liter. Water samples from 9 of the wells and from all the springs had less than 500 milligrams per liter of dissolved solids. There are some long-term trends in the chemistry of water samples from 7 wells having more than 10 years of data and from 2 springs. Rough Rock PM5, Keams Canyon PM2, Second Mesa PM2, and Kayenta PM2 show an increasing trend in dissolved solids; Forest Lake NTUA1 and PWCC 2 show a decreasing trend in dissolved solids; and Kykostmovi PM2 shows a steady trend. Increasing trends in dissolved-solids and chloride concentrations were evident from the more than 11 years of data for 2 springs.

Can water-level management reduce malaria mosquito abundance around large dams in sub-Saharan Africa?

PubMed Central

Wilson, G. Glenn; Ryder, Darren; Tekie, Habte; Petros, Beyene

2018-01-01

Background Water level management has been suggested as a potential tool to reduce malaria around large reservoirs. However, no field-based test has been conducted to assess the effect of water level management on mosquito larval abundance in African settings. The objective of the present study is to evaluate the effects of water level drawdown rates on mosquito larval abundance. Methods Twelve experimental dams were constructed on the foreshore of the Koka Dam in Ethiopia. These were grouped into four daily water drawdown treatments, each with three replicates: no water-level drawdown (Group 1; Control), 10 mm.d-1 (Group 2), 15 mm.d-1 (Group 3) and 20 mm.d-1 (Group 4). Larval sampling was conducted weekly for a period of 6 weeks each in the main malaria transmission season (October to November 2013) and subsequent dry season (February to March 2014). Larval densities were compared among treatments over time using repeated measures Analysis of Variance (ANOVA). Results A total of 284 Anopheles mosquito larvae were collected from the experimental dams during the study period. Most (63.4%; n = 180) were collected during the main malaria transmission season while the remaining (36.6%; n = 104) were collected during the dry season. Larvae comprised four Anopheles species, dominated by Anopheles arabiensis (48.1% of total larval samples; n = 136) and An. pharoensis (33.2%; n = 94). Mean larval density was highest in control treatment dams with stable water levels throughout the study, and decreased significantly (P < 0.05) with increasing water drawdown rates in both seasons. During the main transmission season, anopheline larval density was generally lower by 30%, 70% and 84% in Groups 2, Group 3 and Group 4, respectively, compared with the control dams (Group 1). In the dry season, larval density was reduced by 45%, 70% and 84% in Groups 2, Group 3 and Group 4, respectively, when compared to the control dams. Conclusion Increased water drawdown rates were associated with lower mosquito larval abundance. Water level management could thus serve as a potential control measure for malaria vectors around reservoirs by regulating the persistence of shallow shoreline breeding habitats. Dam operators and water resource managers should consider incorporating water level management as a malaria control mechanism into routine dam operations to manage the risk of malaria transmission to human populations around reservoirs. PMID:29672560

Mouse genetic differences in voluntary wheel running, adult hippocampal neurogenesis and learning on the multi-strain-adapted plus water maze

PubMed Central

Merritt, Jennifer; Rhodes, Justin S.

2014-01-01

Moderate levels of aerobic exercise broadly enhance cognition throughout the lifespan. One hypothesized contributing mechanism is increased adult hippocampal neurogenesis. Recently, we measured the effects of voluntary wheel running on adult hippocampal neurogenesis in 12 different mouse strains, and found increased neurogenesis in all strains, ranging from 2 to 5 fold depending on the strain. The purpose of this study was to determine the extent to which increased neurogenesis from wheel running is associated with enhanced performance on the water maze for 5 of the 12 strains, chosen based on their levels of neurogenesis observed in the previous study (C57BL/6J, 129S1/SvImJ, B6129SF1/J, DBA/2J, and B6D2F1/J). Mice were housed with or without a running wheels for 30 days then tested for learning and memory on the plus water maze, adapted for multiple strains, and rotarod test of motor performance. The first 10 days, animals were injected with BrdU to label dividing cells. After behavioral testing animals were euthanized to measure adult hippocampal neurogenesis using standard methods. Levels of neurogenesis depended on strain but all mice had a similar increase in neurogenesis in response to exercise. All mice acquired the water maze but performance depended on strain. Exercise improved water maze performance in all strains to a similar degree. Rotarod performance depended on strain. Exercise improved rotarod performance only in DBA/2J and B6D2F1/J mice. Taken together, results demonstrate that despite different levels of neurogenesis, memory performance and motor coordination in these mouse strains, all strains have the capacity to increase neurogenesis and improve learning on the water maze through voluntary wheel running. PMID:25435316

Temperatures and Water Levels at Tanana Flats Monitoring Stations

DTIC Science & Technology

2008-04-01

a Druck pressure trans- ducer near the bottom. In response to this drawdown, the initial record showed a water level of 1.13 m on 1 April 2005, which...gradually increased to 1.68 m on 8 April. Freezing of the sensor on 9–10 April ended the reli- able water level record. A pair of replacement Drucks ...again, and a new Druck was installed to replace those that had been frozen. With rising tem- peratures at the bottom of the well, an injection of 400 g

Natural thermal adaptation increases heat shock protein levels and decreases oxidative stress.

PubMed

Oksala, Niku K J; Ekmekçi, F Güler; Ozsoy, Ergi; Kirankaya, Serife; Kokkola, Tarja; Emecen, Güzin; Lappalainen, Jani; Kaarniranta, Kai; Atalay, Mustafa

2014-01-01

Heat shock proteins (HSPs), originally identified as heat-inducible gene products, are a family of highly conserved proteins that respond to a wide variety of stress including oxidative stress. Although both acute and chronic oxidative stress have been well demonstrated to induce HSP responses, little evidence is available whether increased HSP levels provide enhanced protection against oxidative stress under elevated yet sublethal temperatures. We studied relationships between oxidative stress and HSPs in a physiological model by using Garra rufa (doctor fish), a fish species naturally acclimatized to different thermal conditions. We compared fish naturally living in a hot spring with relatively high water temperature (34.4±0.6°C) to those living in normal river water temperature (25.4±4.7°C), and found that levels of all the studied HSPs (HSP70, HSP60, HSP90, HSC70 and GRP75) were higher in fish living in elevated water temperature compared with normal river water temperature. In contrast, indicators of oxidative stress, including protein carbonyls and lipid hydroperoxides, were decreased in fish living in the elevated temperature, indicating that HSP levels are inversely associated with oxidative stress. The present results provide evidence that physiologically increased HSP levels provide protection against oxidative stress and enhance cytoprotection. Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Medrano, Ma Jose, E-mail: pmedrano@isciii.es; Boix, Raquel; Pastor-Barriuso, Roberto

Background: High-chronic arsenic exposure in drinking water is associated with increased cardiovascular disease risk. At low-chronic levels, as those present in Spain, evidence is scarce. In this ecological study, we evaluated the association of municipal drinking water arsenic concentrations during the period 1998-2002 with cardiovascular mortality in the population of Spain. Methods: Arsenic concentrations in drinking water were available for 1721 municipalities, covering 24.8 million people. Standardized mortality ratios (SMRs) for cardiovascular (361,750 deaths), coronary (113,000 deaths), and cerebrovascular (103,590 deaths) disease were analyzed for the period 1999-2003. Two-level hierarchical Poisson models were used to evaluate the association of municipalmore » drinking water arsenic concentrations with mortality adjusting for social determinants, cardiovascular risk factors, diet, and water characteristics at municipal or provincial level in 651 municipalities (200,376 cardiovascular deaths) with complete covariate information. Results: Mean municipal drinking water arsenic concentrations ranged from <1 to 118 {mu}g/L. Compared to the overall Spanish population, sex- and age-adjusted mortality rates for cardiovascular (SMR 1.10), coronary (SMR 1.18), and cerebrovascular (SMR 1.04) disease were increased in municipalities with arsenic concentrations in drinking water >10 {mu}g/L. Compared to municipalities with arsenic concentrations <1 {mu}g/L, fully adjusted cardiovascular mortality rates were increased by 2.2% (-0.9% to 5.5%) and 2.6% (-2.0% to 7.5%) in municipalities with arsenic concentrations between 1-10 and>10 {mu}g/L, respectively (P-value for trend 0.032). The corresponding figures were 5.2% (0.8% to 9.8%) and 1.5% (-4.5% to 7.9%) for coronary heart disease mortality, and 0.3% (-4.1% to 4.9%) and 1.7% (-4.9% to 8.8%) for cerebrovascular disease mortality. Conclusions: In this ecological study, elevated low-to-moderate arsenic concentrations in drinking water were associated with increased cardiovascular mortality at the municipal level. Prospective cohort studies with individual measures of arsenic exposure, standardized cardiovascular outcomes, and adequate adjustment for confounders are needed to confirm these ecological findings. Our study, however, reinforces the need to implement arsenic remediation treatments in water supply systems above the World Health Organization safety standard of 10 {mu}g/L.« less

Estimation of missing water-level data for the Everglades Depth Estimation Network (EDEN), 2013 update

USGS Publications Warehouse

Petkewich, Matthew D.; Conrads, Paul

2013-01-01

The Everglades Depth Estimation Network is an integrated network of real-time water-level gaging stations, a ground-elevation model, and a water-surface elevation model designed to provide scientists, engineers, and water-resource managers with water-level and water-depth information (1991-2013) for the entire freshwater portion of the Greater Everglades. The U.S. Geological Survey Greater Everglades Priority Ecosystems Science provides support for the Everglades Depth Estimation Network in order for the Network to provide quality-assured monitoring data for the U.S. Army Corps of Engineers Comprehensive Everglades Restoration Plan. In a previous study, water-level estimation equations were developed to fill in missing data to increase the accuracy of the daily water-surface elevation model. During this study, those equations were updated because of the addition and removal of water-level gaging stations, the consistent use of water-level data relative to the North American Vertical Datum of 1988, and availability of recent data (March 1, 2006, to September 30, 2011). Up to three linear regression equations were developed for each station by using three different input stations to minimize the occurrences of missing data for an input station. Of the 667 water-level estimation equations developed to fill missing data at 223 stations, more than 72 percent of the equations have coefficients of determination greater than 0.90, and 97 percent have coefficients of determination greater than 0.70.

Hydrology and snowmelt simulation of Snyderville Basin, Park City, and adjacent areas, Summit County, Utah

USGS Publications Warehouse

Brooks, Lynette E.; Mason, James L.; Susong, David D.

1998-01-01

Increasing residential and commercial development is placing increased demands on the ground- and surface-water resources of Snyderville Basin, Park City, and adjacent areas in the southwestern corner of Summit County, Utah. Data collected during 1993-95 were used to assess the quantity and quality of the water resources in the study area.Ground water within the study area is present in consolidated rocks and unconsolidated valley fill. The complex geology makes it difficult to determine the degree of hydraulic connection between different blocks of consolidated rocks. Increased ground-water withdrawal during 1983- 95 generally has not affected ground-water levels. Ground-water withdrawal in some areas, however, caused seasonal fluctuations and a decline in ground-water levels from 1994 to 1995, despite greater-than-normal recharge in the spring of 1995.Ground water generally has a dissolved-solids concentration that ranges from 200 to 600 mg/L. Higher sulfate concentrations in water from wells and springs near Park City and in McLeod Creek and East Canyon Creek than in other parts of the study area are the result of mixing with water that discharges from the Spiro Tunnel. The presence of chloride in water from wells and springs near Park City and in streams and wells near Interstate Highway 80 is probably caused by the dissolution of applied road salt. Chlorofluorocarbon analyses indicate that even though water levels rise within a few weeks of snowmelt, the water took 15 to 40 years to move from areas of recharge to areas of discharge.Water budgets for the entire study area and for six subbasins were developed to better understand the hydrologic system. Ground-water recharge from precipitation made up about 80 percent of the ground-water recharge in the study area. Ground-water discharge to streams made up about 40 percent of the surface water in the study area and ground-water discharge to springs and mine tunnels made up about 25 percent. Increasing use of ground water has the potential to decrease discharge to streams and affect both the amount and quality of surface water in the study area. A comparison of the 1995 to 1994 water budgets emphasizes that the hydrologic system in the study area is very dependent upon the amount of annual precipitation. Although precipitation on the study area was much greater in 1995 than in 1994, most of the additional water resulted in additional streamflow and spring discharge that flows out of the study area. Ground-water levels and groundwater discharge are dependent upon annual precipitation and can vary substantially from year to year.Snowmelt runoff was simulated to assist in estimating ground-water recharge to consolidated rock and unconsolidated valley fill. A topographically distributed snowmelt model controlled by independent inputs of net radiation, meteorological parameters, and snowcover properties was used to calculate the energy and mass balance of the snowcover.

Water-level altitudes and continuous and discrete water quality at and near an aquifer storage and recovery site, Bexar, Atascosa, and Wilson Counties, Texas, June 2004-September 2011

USGS Publications Warehouse

Crow, Cassi L.

2012-01-01

The U.S. Geological Survey (USGS), in cooperation with the San Antonio Water System (SAWS), collected data during 2004–11 to characterize the quality of native groundwater from the San Antonio segment of the Edwards aquifer (hereinafter, Edwards aquifer) and preinjection and postinjection water from the Carrizo aquifer (informal name commonly applied to the upper part of the Carrizo-Wilcox aquifer in the area) at and near an aquifer storage and recovery (ASR) site in Bexar, Atascosa, and Wilson Counties, Texas. Daily mean water-level altitude, water temperature, and specific conductance were measured continuously in a monitoring well on the ASR site to determine how injection and withdrawal at the ASR site might affect local groundwater. Groundwater samples were collected and analyzed for selected physical properties and constituents to characterize the quality of native groundwater from the Edwards aquifer and preinjection and postinjection water from the Carrizo aquifer near the ASR site to provide a better understanding of possible changes in the quality of groundwater near an active ASR site that might result from the mixing of water from different aquifers. During injection periods, the water-level altitude in the monitoring well generally increased as the amount of water being injected into all wells at the ASR site increased and decreased as the amount of water being injected into all wells at the ASR site decreased. During withdrawal periods, the water-level altitude in the monitoring well generally increased as the total volume of water being withdrawn from all wells at the ASR site decreased and generally decreased as the total volume of water being withdrawn from all wells increased. Daily mean water temperature fluctuated by less than 1 degree Celsius and was determined to be independent of injection or withdrawal conditions at the ASR site. Changes in daily mean specific-conductance values measured at four depths in the monitoring well at the ASR site occurred without regard to total ASR site injection or withdrawal volumes. No substantial differences were measured over time in major-ion, trace-element, or isotope chemistry of water samples collected from the wells that supplied water from the Edwards aquifer. Little variation in water chemistry was detected in the samples collected from four wells designed to inject and withdraw water at the ASR site, regardless of whether the ASR site was injecting or withdrawing water. The similarity of major-ion and isotope chemistry between the Edwards aquifer source wells and the four ASR wells indicates that little, if any, migration of injected water away from the ASR wells has occurred. In a well located closest to the ASR site in the direction of regional flow for the Carrizo aquifer, a greater alkalinity value and a smaller concentration of chloride were measured in the most recent sample than in all other samples collected at this well. Substantial increases in dissolved iron and manganese concentrations also were observed in this well. The increased alkalinity value and dissolved iron and manganese concentrations and the decreased chloride concentration in the well could indicate that the injected water from the Edwards aquifer had begun to move into at least a part of the strata supplying these wells and might be causing iron and manganese mobilization in the Carrizo aquifer.

Blue water scarcity and the economic impacts of future agricultural trade and demand

NASA Astrophysics Data System (ADS)

Schmitz, Christoph; Lotze-Campen, Hermann; Gerten, Dieter; Dietrich, Jan Philipp; Bodirsky, Benjamin; Biewald, Anne; Popp, Alexander

2013-06-01

An increasing demand for agricultural goods affects the pressure on global water resources over the coming decades. In order to quantify these effects, we have developed a new agroeconomic water scarcity indicator, considering explicitly economic processes in the agricultural system. The indicator is based on the water shadow price generated by an economic land use model linked to a global vegetation-hydrology model. Irrigation efficiency is implemented as a dynamic input depending on the level of economic development. We are able to simulate the heterogeneous distribution of water supply and agricultural water demand for irrigation through the spatially explicit representation of agricultural production. This allows in identifying regional hot spots of blue water scarcity and explicit shadow prices for water. We generate scenarios based on moderate policies regarding future trade liberalization and the control of livestock-based consumption, dependent on different population and gross domestic product (GDP) projections. Results indicate increased water scarcity in the future, especially in South Asia, the Middle East, and north Africa. In general, water shadow prices decrease with increasing liberalization, foremost in South Asia, Southeast Asia, and the Middle East. Policies to reduce livestock consumption in developed countries not only lower the domestic pressure on water but also alleviate water scarcity to a large extent in developing countries. It is shown that one of the two policy options would be insufficient for most regions to retain water scarcity in 2045 on levels comparable to 2005.

Visioning the Future: Scenarios Modeling of the Florida Coastal Everglades

NASA Astrophysics Data System (ADS)

Flower, Hilary; Rains, Mark; Fitz, Carl

2017-11-01

In this paper, we provide screening-level analysis of plausible Everglades ecosystem response by 2060 to sea level rise (0.50 m) interacting with macroclimate change (1.5 °C warming, 7% increase in evapotranspiration, and rainfall that either increases or decreases by 10%). We used these climate scenarios as input to the Ecological Landscape Model to simulate changes to seven interactive hydro-ecological metrics. Mangrove forest and other marine influences migrated up to 15 km inland in both scenarios, delineated by the saltwater front. Freshwater habitat area decreased by 25-30% under our two climate change scenarios and was largely replaced by mangroves and, in the increased rainfall scenario, open water as well. Significant mangroves drowned along northern Florida Bay in both climate change scenarios due to sea level rise. Increased rainfall of 10% provided significant benefits to the spatial and temporal salinity regime within the marine-influenced zone, providing a more gradual and natural adjustment for at-risk flora and fauna. However, increased rainfall also increased the risk of open water, due to water depths that inhibited mangrove establishment and reduced peat accumulation rates. We infer that ecological effects related to sea level rise may occur in the extreme front-edge of saltwater intrusion, that topography will control the incursion of this zone as sea level rises, and that differences in freshwater availability will have ecologically significant effects on ecosystem resilience through the temporal and spatial pattern of salinity changes.

Visioning the Future: Scenarios Modeling of the Florida Coastal Everglades.

PubMed

Flower, Hilary; Rains, Mark; Fitz, Carl

2017-11-01

In this paper, we provide screening-level analysis of plausible Everglades ecosystem response by 2060 to sea level rise (0.50 m) interacting with macroclimate change (1.5 °C warming, 7% increase in evapotranspiration, and rainfall that either increases or decreases by 10%). We used these climate scenarios as input to the Ecological Landscape Model to simulate changes to seven interactive hydro-ecological metrics. Mangrove forest and other marine influences migrated up to 15 km inland in both scenarios, delineated by the saltwater front. Freshwater habitat area decreased by 25-30% under our two climate change scenarios and was largely replaced by mangroves and, in the increased rainfall scenario, open water as well. Significant mangroves drowned along northern Florida Bay in both climate change scenarios due to sea level rise. Increased rainfall of 10% provided significant benefits to the spatial and temporal salinity regime within the marine-influenced zone, providing a more gradual and natural adjustment for at-risk flora and fauna. However, increased rainfall also increased the risk of open water, due to water depths that inhibited mangrove establishment and reduced peat accumulation rates. We infer that ecological effects related to sea level rise may occur in the extreme front-edge of saltwater intrusion, that topography will control the incursion of this zone as sea level rises, and that differences in freshwater availability will have ecologically significant effects on ecosystem resilience through the temporal and spatial pattern of salinity changes.

Geochemical characterization of shallow ground water in the Eutaw aquifer, Montgomery, Alabama

USGS Publications Warehouse

Robinson, J.L.; Journey, C.A.

2004-01-01

Ground water samples were collected from 30 wells located in, or directly down gradient from, recharge areas of the Eutaw aquifer in Montgomery, Alabama. The major ion content of the water evolves from calcium-sodium-chloride- dominated type in the recharge area to calcium-bicarbonate-dominated type in the confined portion of the aquifer. Ground water in the recharge area was undersaturated with respect to aluminosilicate and carbonate minerals. Ground water in the confined portion of the aquifer was at equilibrium levels for calcite and potassium feldspar. Dissolved oxygen and nitrite-plus-nitrate concentrations decreased as ground water age increased; pH, iron, and sulfate concentrations increased as ground water age increased. Aluminum, copper, and zinc concentrations decreased as ground water age and pH increased. These relations indicate that nitrate, aluminum, copper, and zinc are removed from solution as water moves from recharge areas to the confined areas of the Eutaw aquifer. The natural evolution of ground water quality, which typically increases the pH and decreases the dissolved oxygen content, may be an important limiting factor to the migration of nitrogen based compounds and metals.

Training-induced elevations in extracellular lactate in hippocampus and striatum: Dissociations by cognitive strategy and type of reward.

PubMed

Newman, Lori A; Scavuzzo, Claire J; Gold, Paul E; Korol, Donna L

2017-01-01

Recent evidence suggests that astrocytes convert glucose to lactate, which is released from the astrocytes and supports learning and memory. This report takes a multiple memory perspective to test the role of astrocytes in cognition using real-time lactate measurements during learning and memory. Extracellular lactate levels in the hippocampus or striatum were determined with lactate biosensors while rats were learning place (hippocampus-sensitive) or response (striatum-sensitive) versions of T-mazes. In the first experiment, rats were trained on the place and response tasks to locate a food reward. Extracellular lactate levels in the hippocampus increased beyond those of feeding controls during place training but not during response training. However, striatal lactate levels did not increase beyond those of controls when rats were trained on either the place or the response version of the maze. Because food ingestion itself increased blood glucose and brain lactate levels, the contribution of feeding may have confounded the brain lactate measures. Therefore, we conducted a second similar experiment using water as the reward. A very different pattern of lactate responses to training emerged when water was used as the task reward. First, provision of water itself did not result in large increases in either brain or blood lactate levels. Moreover, extracellular lactate levels increased in the striatum during response but not place learning, whereas extracellular lactate levels in the hippocampus did not differ across tasks. The findings from the two experiments suggest that the relative engagement of the hippocampus and striatum dissociates not only by task but also by reward type. The divergent lactate responses of the hippocampus and striatum in place and response tasks under different reward conditions may reflect ethological constraints tied to foraging for food and water. Copyright © 2016 Elsevier Inc. All rights reserved.

Nitrate and drinking water from private wells: will there be an epidemic of cancers of the digestive tract, urinary bladder and thyroid?

PubMed

Njeze, G E; Dilibe, U; Ilo, C

2014-01-01

To estimate the nitrate levels in private wells located in different parts of Enugu and discuss the future health implications following chronic ingestion of well water. The map of Enugu was used to divide the city into many 25 units, using grid lines 1 cm apart. Cluster sampling method was used to collect samples. These samples were sent to two laboratories for estimation of nitrate levels. The people drawing water from the different wells were interviewed to determine what they used the water for. The subjects who were interviewed said they ingested the water. The nitrate levels found in these wells (median value of 31 mg/L) were significantly higher than the internationally accepted levels of nitrate in water for ingestion, (P < 0.0001). High nitrate levels drinking water is dangerous to health and can cause methemoglobinemia in children. It may also increase cancer risk in adults because nitrate is endogenously reduced to nitrite and subsequent nitrosation reactions give rise to N-nitroso compounds (NOCs), which are highly carcinogenic and can act systemically.

Water trimer torsional spectrum from accurate ab initio and semiempirical potentials

NASA Astrophysics Data System (ADS)

van der Avoird, Ad; Szalewicz, Krzysztof

2008-01-01

The torsional levels of (H2O)3 and (D2O)3 were calculated in a restricted dimensionality (three-dimensional) model with several recently proposed water potentials. Comparison with the experimental data provides a critical test, not only of the pair interactions that have already been probed on the water dimer spectra, but also of the nonadditive three-body contributions to the potential. The purely ab initio CC-pol and HBB potentials that were previously shown to yield very accurate water dimer levels, also reproduce the trimer levels well when supplemented with an appropriate three-body interaction potential. The TTM2.1 potential gives considerably less good agreement with experiment. Also the semiempirical VRT(ASP-W)III potential, fitted to the water dimer vibration-rotation-tunneling levels, gives substantial disagreement with the measured water trimer levels, which shows that the latter probe the potential for geometries other than those probed by the dimer spectrum. Although the three-body nonadditive interactions significantly increase the stability of the water trimer, their effect on the torsional energy barriers and vibration-tunneling frequencies is less significant.

Ground Water in the Anchorage Area, Alaska--Meeting the Challenges of Ground-Water Sustainability

USGS Publications Warehouse

Moran, Edward H.; Galloway, Devin L.

2006-01-01

Ground water is an important component of Anchorage's water supply. During the 1970s and early 80s when ground water extracted from aquifers near Ship Creek was the principal source of supply, area-wide declines in ground-water levels resulted in near record low streamflows in Ship Creek. Since the importation of Eklutna Lake water in the late 1980s, ground-water use has been reduced and ground water has contributed 14-30 percent of the annual supply. As Anchorage grows, given the current constraints on the Eklutna Lake water availability, the increasing demand for water could place an increasing reliance on local ground-water resources. The sustainability of Anchorage's ground-water resources challenges stakeholders to develop a comprehensive water-resources management strategy.

Louisiana Ground-Water Map No. 22: Generalized Potentiometric Surface of the Amite Aquifer and the "2,800-Foot" Sand of the Baton Rouge Area in Southeastern Louisiana, June-August 2006

USGS Publications Warehouse

Fendick, Robert B.

2007-01-01

The Amite aquifer and the '2,800-foot' sand of the Baton Rouge area (hereafter referred to as the '2,800-foot' sand) are principal sources of fresh ground water in southeastern Louisiana. Both the Amite aquifer and the '2,800-foot' sand are part of the Jasper equivalent aquifer system. The Amite aquifer is heavily pumped in the Bogalusa area, and the '2,800-foot' sand is one of the most heavily pumped aquifers in East Baton Rouge Parish. The Baton Rouge fault zone, which acts as a barrier to flow, trends approximately west-northwest from a point just south of The Rigolets through southern West Baton Rouge Parish, and is the approximate southern limit of freshwater in the aquifers. For the purposes of this report, freshwater is defined as water having less than 250 milligrams per liter (mg/L) of chloride, and most of the water withdrawals described in this report were assumed to be fresh. In 2005, about 18 million gallons per day (Mgal/d) was withdrawn from the Amite aquifer, primarily for public-supply use (8.4 Mgal/d) and industrial use (9.6 Mgal/d). During this same period, about 32 Mgal/d was withdrawn from the '2,800-foot' sand, primarily for public-supply use (13 Mgal/d) and industrial use (19 Mgal/d). Public-supply and industrial withdrawals from the Amite aquifer and the '2,800-foot' sand are listed in table 1. According to data from the Louisiana State Census Data Center, some of the largest population increases in the State during the period 1990 to 2000 occurred in St. Tammany (32.4 percent), Livingston (30.2 percent), and Tangipahoa (17.4 percent) Parishes. These population increases have been accompanied by increased withdrawals of ground water during the same period: 40 percent in St. Tammany Parish, 63 percent in Livingston Parish, and 35 percent in Tangipahoa Parish. An increase in population in these parishes is expected from population displacement due to damages from Hurricanes Katrina and Rita crossing the Louisiana coast in August and September of 2005. Additional information about ground-water flow and effects of increased withdrawals on water levels in the Amite aquifer and the '2,800-foot' sand is needed to assess ground-water-development potential and to protect this resource. To meet this need, the U.S. Geological Survey, in cooperation with the Louisiana Department of Transportation and Development, began a study in 2005 to determine water levels, flow direction, and water-level trends for the Amite aquifer and '2,800-foot' sand. This report presents data and a map that describe the generalized potentiometric surface of the Amite aquifer and '2,800-foot' sand in southeastern Louisiana. Graphs of water levels in selected wells and a table of withdrawals from the Amite aquifer and '2,800-foot' sand show historical changes in water levels and water use. The generalized potentiometric-surface map illustrates the water levels and ground-water flow directions for June-August 2006. These data are on file at the USGS office in Baton Rouge, Louisiana.

Increased levels of arginine vasotocin and neurophysin during nesting in sea turtles.

PubMed

Figler, R A; MacKenzie, D S; Owens, D W; Licht, P; Amoss, M S

1989-02-01

Arginine vasotocin (AVT) and neurophysin (NP) levels were measured by radioimmunoassay in two species of sea turtle, the olive ridley, Lepidochelys olivacea, and the loggerhead, Caretta caretta, during the brief period of nesting and oviposition. In both species, AVT was low in animals which were not reproductively active. AVT was also low at the time animals emerged from the surf to nest, but increased significantly during oviposition and then declined as the animals returned to the water. NP increased in concert with AVT, also reaching highest levels during oviposition. In both species, however, NP levels remained elevated over prenesting levels at the time of return to the water. These findings are consistent with the hypothesis that an AVT-neurophysin complex is released from the neurohypophysis during nesting, and that AVT is a physiological regulator of oviducal contractions in sea turtles.

Regional hydrology and simulation of deep ground-water flow in the Southeastern Coastal Plain aquifer system in Mississippi, Alabama, Georgia, and South Carolina

USGS Publications Warehouse

Barker, R.A.; Pernik, Maribeth

1994-01-01

The Southeastern Coastal Plain aquifer system is a coastward-sloping, wedge-shaped sand and gravel reservoir exposed in outcrop to a humid climate and drained by an extensive surface-water network. Ground-water pumpage has increased to about 765 cubic feet per second since 1900, causing water-level declines of more than 150 feet in places, while base flow to major streams has decreased about 350 cubic feet per second. The water-level declines and adjustments in recharge and discharge are not expected to seriously restrict future ground-water development.

Occurrence of aromatic amines and N-nitrosamines in the different steps of a drinking water treatment plant.

PubMed

Jurado-Sánchez, Beatriz; Ballesteros, Evaristo; Gallego, Mercedes

2012-09-15

The occurrence of 24 amines within a full scale drinking water treatment plant that used chlorinated agents as disinfectants was evaluated for the first time in this research. Prior to any treatment (raw water), aniline, 3-chloroaniline, 3,4-dichloroaniline and N-nitrosodimethylamine were detected at low levels (up to 18 ng/L) but their concentration increased ∼10 times after chloramination while 9 new amines were produced (4 aromatic amines and 5 N-nitrosamines). Within subsequent treatments, there were no significant changes in the amine levels, although the concentrations of 2-nitroaniline, N-nitrosodimethylamine and N-nitrosodiethylamine increased slightly within the distribution system. Eleven of the 24 amines studied were undetected either in the raw and in the treatment plant samples analysed. There is an important difference in the behaviour of the aromatic amines and N-nitrosamines with respect to water temperature and rainfall events. Amine concentrations were higher in winter due to low water temperatures, this effect being more noticeable for N-nitrosamines. Aromatic amines were detected at their highest concentrations (especially 3,4-dichloroaniline and 2-nitroaniline) in treated water after rainfall events. These results may be explained by the increase in the levels of amine precursors (pesticides and their degradation products) in raw water since the rainfall facilitated the transport of these compounds from soil which was previously contaminated as a result of intensive agricultural practices. Copyright © 2012 Elsevier Ltd. All rights reserved.

Consumption of low-moderate level arsenic contaminated water does not increase spontaneous pregnancy loss: a case control study.

PubMed

Bloom, Michael S; Neamtiu, Iulia A; Surdu, Simona; Pop, Cristian; Lupsa, Ioana Rodica; Anastasiu, Doru; Fitzgerald, Edward F; Gurzau, Eugen S

2014-10-13

Previous work suggests an increased risk for spontaneous pregnancy loss linked to high levels of inorganic arsenic (iAs) in drinking water sources (>10 μg/L). However, there has been little focus to date on the impact of low-moderate levels of iAs in drinking water (<10 μg/L). To address this data gap we conducted a hospital-based case-control study in Timis County, Romania. We recruited women with incident spontaneous pregnancy loss of 5-20 weeks completed gestation as cases (n = 150), and women with ongoing pregnancies matched by gestational age (±1 week) as controls (n = 150). Participants completed a physician-administered questionnaire and we collected water samples from residential drinking sources. We reconstructed residential drinking water exposure histories using questionnaire data weighted by iAs determined using hydride generation-atomic absorption spectrometry (HG-AAS). Logistic regression models were used to generate odds ratios (OR) and 95% confidence intervals (CI) for associations between iAs exposure and loss, conditioned on gestational age and adjusted for maternal age, cigarette smoking, education and prenatal vitamin use. We explored potential interactions in a second set of models. Drinking water arsenic concentrations ranged from 0.0 to 175.1 μg/L, with median 0.4 μg/L and 90th%tile 9.4 μg/L. There were no statistically significant associations between loss and average or peak drinking water iAs concentrations (OR 0.98, 95% CI 0.96-1.01), or for daily iAs intake (OR 1.00, 95% CI 0.98-1.02). We detected modest evidence for an interaction between average iAs concentration and cigarette smoking during pregnancy (P = 0.057) and for daily iAs exposure and prenatal vitamin use (P = 0.085). These results suggest no increased risk for spontaneous pregnancy loss in association with low to moderate level drinking water iAs exposure. Though imprecise, our data also raise the possibility for increased risk among cigarette smokers. Given the low exposures overall, these data should reassure pregnant women and policy makers with regard to the potential effect of drinking water iAs on early pregnancy, though a larger more definitive study to investigate the potential risk increase in conjunction with cigarette smoking is merited.

Parthenolide and abscisic acid synthesis in feverfew are associated but environmental factors affect them dissimilarly.

PubMed

Fonseca, Jorge M; Rushing, James W; Rajapakse, Nihal C; Thomas, Ronald L; Riley, Melissa B

2005-05-01

The effect of harvest time, shading prior to harvest and water stress on parthenolide (PRT) concentration in feverfew and its possible connection with the abscisic acid (ABA) pathway were investigated. In plants harvested at different times of the day, acetumar the PRT levels were highest during late afternoon while ABA levels were greatest during morning hours. Shading plants during the afternoon prior to harvest caused a two-fold increase in ABA and no significant difference in PRT levels. ABA was higher in water-stressed plants while PRTcontent increased in plants following recovery from a water stress event. ABA inhibitors, norflurazon, sodium tungstate, naproxen and sodium bisulfite, were used to determine the connection between the biosynthesis of PRTand ABA. Norflurazon and naproxen reduced PRT concentration in cut flowers and in 2-month old plants. Sodium bisulfite and sodium tungstate reduced PRT only in cut flowers. Application of 2,4-D, a promoter of ABA synthesis, to potted plants resulted in a 2.5 fold increase in PRT levels. The inhibition of PRT formation in response to ABA inhibitors and the increase in PRT concentration observed with 2,4-D application indicated that PRT is derived from carotenoid synthesis similarly to ABA and not directly from farnesyl pyrosphosphate (FPP) as suggested for other sesquiterpene Lactones. However, PRT and ABA levels are affected dissimilarly by environmental conditions. The overall results of the study indicated that simple agricultural practices, such as harvesting during afternoon and subjecting plants to a single water stress event, can increase PRT concentration in the final feverfew product with no additional costs of production prior to harvest.

Analysis of water-level fluctuations in Wisconsin wells

USGS Publications Warehouse

Patterson, G.L.; Zaporozec, A.

1987-01-01

Long-term trends are apparent on hydrographs of wells Br-46, Mr-2S, Pt-276, Ro-3, and Ve-8. The trend of average annual water levels has been generally increasing since the late 1950's and is in general agreement with the increasing trend of precipitation. Hydrographs of well Ve-8, which has the longest period of record in Wisconsin, indicate that the generally rising trend started even earlier at the end of an extensive drought period in the 1930's.

Land subsidence in the San Joaquin Valley, California, USA, 2007-2014

NASA Astrophysics Data System (ADS)

Sneed, M.; Brandt, J. T.

2015-11-01

Rapid land subsidence was recently measured using multiple methods in two areas of the San Joaquin Valley (SJV): between Merced and Fresno (El Nido), and between Fresno and Bakersfield (Pixley). Recent land-use changes and diminished surface-water availability have led to increased groundwater pumping, groundwater-level declines, and land subsidence. Differential land subsidence has reduced the flow capacity of water-conveyance systems in these areas, exacerbating flood hazards and affecting the delivery of irrigation water. Vertical land-surface changes during 2007-2014 were determined by using Interferometric Synthetic Aperture Radar (InSAR), Continuous Global Positioning System (CGPS), and extensometer data. Results of the InSAR analysis indicate that about 7600 km2 subsided 50-540 mm during 2008-2010; CGPS and extensometer data indicate that these rates continued or accelerated through December 2014. The maximum InSAR-measured rate of 270 mm yr-1 occurred in the El Nido area, and is among the largest rates ever measured in the SJV. In the Pixley area, the maximum InSAR-measured rate during 2008-2010 was 90 mm yr-1. Groundwater was an important part of the water supply in both areas, and pumping increased when land use changed or when surface water was less available. This increased pumping caused groundwater-level declines to near or below historical lows during the drought periods 2007-2009 and 2012-present. Long-term groundwater-level and land-subsidence monitoring in the SJV is critical for understanding the interconnection of land use, groundwater levels, and subsidence, and evaluating management strategies that help mitigate subsidence hazards to infrastructure while optimizing water supplies.

Association between drinking water uranium content and cancer risk in Bavaria, Germany.

PubMed

Radespiel-Tröger, M; Meyer, M

2013-10-01

To evaluate the possible association between uranium (U) content in public drinking water on the one hand and the risk of cancer of the colorectum, lung, female breast, prostate, kidney, and urinary bladder, total cancer, and leukemia on the other hand in Bavaria, an ecologic study on the level of municipalities was performed. Cancer incidence data for the years 2002-2008 were obtained from the population-based cancer registry Bavaria according to sex. Current U content data of public drinking water on the level of municipalities were obtained from a publicly available source. The possible association between drinking water U content and cancer risk adjusted for average socio-economic status was evaluated using Poisson regression. Drinking water U content was below 20 μg/L in 458 out of 461 included municipalities. We found a significantly increased risk of leukemia in men in the intermediate (U level, 1.00-4.99 μg/L; relative risk [RR], 1.14) and in the highest U exposure category (U level, ≥5 μg/L; RR, 1.28). Moreover, in women, a significantly elevated risk was identified with respect to kidney cancer in the highest exposure category (RR, 1.16) and with respect to lung cancer in the intermediate exposure category (RR, 1.12). The slightly increased risk of leukemia in men, kidney cancer in women, and lung cancer in women may require further investigation. If an increased cancer risk is confirmed, preventive measures (e.g., introduction of U filters in public water systems) may be considered.

Desiccation and freezing tolerance of embryonic axes from Citrus sinensis [L.] osb. pretreated with sucrose.

PubMed

Santos, Izulmé R I; Stushnoff, Cecil

2003-01-01

Embryonic axes of Citrus sinensis L. were successfully cryopreserved. While fully hydrated unfrozen axes germinated 100%, survival decreased as axes water content dropped, and total loss of viability was observed when the water content dropped to 0.04 and 0.10 mg H2O/mg dry mass, for axes without and with sucrose preculture, respectively. Fully hydrated axes did not survive exposure to liquid nitrogen. Highest seedling recovery (93-100%) for untreated axes was observed at 0.26 to 0.15 mg H2O/mg dry mass. Differential scanning calorimetry revealed the presence of broad melting peaks in fully hydrated embryonic axes. The size of the melting peak diminished as water was removed by desiccation. Minimum melting of water was observed at the point axes survived cryopreservation. Occurrence of a glass transition upon warming was not a condition for axes to survive liquid nitrogen exposure. In untreated axes, glucose, increased with desiccation to 0.2 mg H2O/mg dry mass, and decreased as the axes were desiccated to lower water contents. Fructose and sucrose levels did not increase when untreated samples were desiccated for the same periods of time. Raffinose and stachyose levels decreased as untreated and precultured embryonic axes were desiccated. In sucrose precultured axes, sucrose and fructose levels increased when they were dehydrated, reaching maximum levels at 0.2 mg H2O/mg dry mass. Tissue glucose did not change significantly with desiccation. Raffinose and stachyose levels dropped as precultured embryonic axes were dried.

Simulated Ground-Water Withdrawals by Cabot WaterWorks from the Mississippi River Valley Alluvial Aquifer, Lonoke County, Arkansas

USGS Publications Warehouse

Czarnecki, John B.

2007-01-01

Cabot WaterWorks, located in Lonoke County, Arkansas, plans to increase ground-water withdrawals from the Mississippi River Valley alluvial aquifer from a 2004 rate of approximately 2.24 million gallons per day to between 4.8 and 8 million gallons per day by the end of 2049. The effects of increased pumping from several wells were simulated using a digital model of ground-water flow. The proposed additional withdrawals by Cabot WaterWorks were specified in three 1-square-mile model cells with increased pumping beginning in 2007. Increased pumping was specified at various combined rates for a period of 44 years. In addition, augmented pumping from wells owned by Grand Prairie Water Users Association, located about 2 miles from the nearest Cabot WaterWorks wells, was added to the model beginning in 2007 and continuing through to the end of 2049 in 10 of the 16 scenarios analyzed. Eight of the scenarios included reductions in pumping rates in model cells corresponding to either the Grand Prairie Water Users Association wells or to wells contained within the Grand Prairie Area Demonstration Project. Drawdown at the end of 44 years of pumping at 4.8 million gallons per day from the Cabot WaterWorks wells ranged from 15 to 25 feet in the three model cells; pumping at 8 million gallons per day resulted in water-level drawdown ranging from about 15 to 40 feet. Water levels in those cells showed no indication of leveling out at the end of the simulation period, indicating non-steady-state conditions after 44 years of pumping. From one to four new dry cells occurred in each of the scenarios by the end of 2049 when compared to a baseline scenario in which pumping was maintained at 2004 rates, even in scenarios with reduced pumping in the Grand Prairie Area Demonstration Project; however, reduced pumping produced cells that were no longer dry when compared to the baseline scenario at the end of 2049. Saturated thickness at the end of 2049 in the three Cabot WaterWorks wells ranged from about 52 to 68.5 feet for pumping rates of 4.8 million gallons per day, and from about 38 to 64 feet for pumping rates of 8 million gallons per day, the latter causing water level to fall below half the aquifer thickness in the most heavily pumped of the three cells.

Louisiana Coastal Area, Louisiana. Notice of Study Findings. Water Supply

DTIC Science & Technology

1984-09-01

without a reel or artificial bait. 33 0 Hunting activities are as varied as fishing activities. Hunting for small game is the most prevalent activity and a...structure would be severe. Artificial elevation and manipulation of the water level in the incoming streams could be detrimental to the fishery and...routes that presently exist. In addition, artificial manipulation of the water levels would increase an already acute erosion problem in the area

Water Stress in Global Transboundary River Basins: Significance of Upstream Water Use on Downstream Stress

NASA Technical Reports Server (NTRS)

Munia, H.; Guillaume, J. H. A.; Mirumachi, N.; Porkka,M.; Wada, Yoshihide; Kummu, M.

2016-01-01

Growing population and water demand have increased pressure on water resources in various parts of the globe, including many transboundary river basins. While the impacts of upstream water use on downstream water availability have been analyzed in many of these international river basins, this has not been systematically done at the global scale using coherent and comparable datasets. In this study, we aim to assess the change in downstream water stress due to upstream water use in the world's transboundary river basins. Water stress was first calculated considering only local water use of each sub-basin based on country-basin mesh, then compared with the situation when upstream water use was subtracted from downstream water availability. Wefound that water stress was generally already high when considering only local water use, affecting 0.95-1.44 billion people or 33%-51% of the population in transboundary river basins. After accounting for upstream water use, stress level increased by at least 1 percentage-point for 30-65 sub-basins, affecting 0.29-1.13 billion people. Altogether 288 out of 298 middle-stream and downstream sub-basin areas experienced some change in stress level. Further, we assessed whether there is a link between increased water stress due to upstream water use and the number of conflictive and cooperative events in the transboundary river basins, as captured by two prominent databases. No direct relationship was found. This supports the argument that conflicts and cooperation events originate from a combination of different drivers, among which upstream-induced water stress may play a role. Our findings contribute to better understanding of upstream-downstream dynamics in water stress to help address water allocation problems.

Water reuse and cost-benefit of pumping at different spatial levels in a rice irrigation system in UPRIIS, Philippines

NASA Astrophysics Data System (ADS)

Hafeez, M. M.; Bouman, B. A. M.; Van de Giesen, N.; Mushtaq, S.; Vlek, P.; Khan, S.

As agricultural water resources in Asia become increasingly scarce, the irrigation efficiency of rice must be improved. However, in this region there is very limited information available about water use efficiency across spatial levels in irrigation systems. This study quantifies the volume of water reuse and its related cost-benefits at five different spatial levels, ranging from 1500 ha to 18,000 ha, under gravity-fed irrigation system in Upper Pumpanga River Integrated Irrigation System (UPRIIS), Philippines. The major sources of water reuse are considered, namely groundwater pumping, pumping from creeks, combined use and irrigation supplies from check dams. The volume of water available from all four sources of water reuse was quantified through extensive measurements. Production functions were developed to quantify water-yield relationships and to measure the economic value of water reuse. This study was conducted during the dry season of 2001, which existed from 19 November 2000 until 18 May 2001. The water reuse by pumping and check dams was 7% and 22% of the applied surface water at District 1 level. The reuse of surface water through check dams increased linearly with 4.6 Mm 3 per added 1000 ha. Similarly, the total amount of reused water from pumping is equivalent to 30% of the water lost through rice evapotranspiration during the dry season 2001. The results showed that water reuse plays a dominant role in growing a rice crop during the dry season. The result showed no difference in pumping costs between the creek (US0.011/m 3) and shallow pumps (US0.012/m 3). The marginal value of productivity (MVP) of water reuse from creek (US0.044/m 3) was slightly higher than the water reuse through the pumping ground water (US0.039/m 3). Results also indicated that the total volume pumped per ha (m 3/ha) was ranging from 0.39 to 6.93 m 3/ha during the dry season. The results clearly indicate that the quantification of amount of water reuse is very crucial for understanding and finding of water use efficiency at the irrigation system level. The results also revealed that rice production systems are still profitable despite high pumping costs and other associated expenses at all spatial levels in District 1. More than 1500 farmers, from a total of 10,000, use 1154 pumps to draw water from shallow tube wells (or from drains and creeks) for supplementary irrigation at a District level. Reuse of water plays a vital role in growing a profitable rice crop during the dry season.

Groundwater levels, trends, and relations to pumping in the Bureau of Reclamation Klamath Project, Oregon and California

USGS Publications Warehouse

Gannett, Marshall W.; Breen, Katherine H.

2015-07-28

The use of groundwater to supplement surface-water supplies for the Bureau of Reclamation Klamath Project in the upper Klamath Basin of Oregon and California markedly increased between 2000 and 2014. Pre-2001 groundwater pumping in the area where most of this increase occurred is estimated to have been about 28,600 acre-feet per year. Subsequent supplemental pumping rates have been as high as 128,740 acre-feet per year. During this period of increased pumping, groundwater levels in and around the Bureau of Reclamation Klamath Project have declined by about 20-25 feet. Water-level declines are largely due to the increased supplemental pumping, but other factors include increased pumping adjacent to the Klamath Project and drying climate conditions. This report summarizes the distribution and magnitude of supplemental groundwater pumping and groundwater-level declines, and characterizes the relation between the stress and response in subareas of the Klamath Project to aid decision makers in developing groundwater-management strategies.

Dental caries, its surface susceptibility and dental fluorosis in South India.

PubMed

Acharya, Shashidhar

2005-12-01

To correlate water fluoride levels with dental caries and dental fluorosis in areas with different levels of fluoride in the drinking water and to establish the surface susceptibility of dental caries in an endemic fluoride area. 544 schoolchildren 12 to 15 years of age from the Davangere region of India were examined. The DMFS index was used to measure dental caries, which was further differentiated into smooth surface and pit and fissure lesions. Dean's index was used to diagnose dental fluorosis. Five villages with fluoride levels ranging from 0.43 ppm to 3.41 ppm were studied. There was a highly significant negative correlation (r = -0.16) between water fluoride levels and dental caries. Dental fluorosis increased from 16% at 0.43 ppm to 100% at 3.41 ppm. Pit and fissure lesions made up the vast majority of the lesions in all the villages and showed a decreasing trend with increasing fluoride levels, however no such trend was seen for smooth surface lesions. Water fluoride was an important factor responsible for the low caries prevalence. The prevalence of fluorosis and low caries even in low fluoride areas may point to a halo effect.

Impact of climate change on Gironde Estuary

NASA Astrophysics Data System (ADS)

Laborie, Vanessya; Hissel, François; Sergent, Philippe

2014-05-01

Within the THESEUS European project, a simplified mathematical model for storm surge levels in the Bay of Biscay was adjusted on 10 events at Le Verdon using wind and pressure fields from CLM/SGA, so that the water levels at Le Verdon have the same statistic quantiles as observed tide records for the period [1960-2000]. The analysis of future storm surge levels shows a decrease in their quantiles at Le Verdon, whereas there is an increase of the quantiles of total water levels. This increase is smaller than the sea level rise and gets even smaller as one enters farther upstream in the estuary. A numerical model of the Gironde Estuary was then used to evaluate future water levels at 6 locations of the estuary from Le Verdon to Bordeaux and to assess the changes in the quantiles of water levels during the XXIst century using ONERC's pessimistic scenario for sea level rise (60 cm). The model was fed by several data sources : wind fields at Royan and Mérignac interpolated from the grid of the European Climatolologic Model CLM/SGA, a tide signal at Le Verdon, the discharges of Garonne (at La Réole), the Dordogne (at Pessac) and Isle (at Libourne). A series of flood maps for different return periods between 2 and 100 years and for four time periods ([1960-1999], [2010-2039], [2040-2069] and [2070-2099]) have been built for the region of Bordeaux. Quantiles of water levels in the floodplain have also been calculated. The impact of climate change on the evolution of flooded areas in the Gironde Estuary and on quantiles of water levels in the floodplain mainly depends on the sea level rise. Areas which are not currently flooded for low return periods will be inundated in 2100. The influence of river discharges and dike breaching should also be taken into account for more accurate results.

Household Effectiveness vs. Laboratory Efficacy of Point-of-use Chlorination

PubMed Central

Levy, Karen; Anderson, Larissa; Robb, Katharine A.; Cevallos, William; Trueba, Gabriel; Eisenberg, Joseph N.S.

2014-01-01

Treatment of water at the household level offers a promising approach to combat the global burden of diarrheal diseases. In particular, chlorination of drinking water has been a widely promoted strategy due to persistence of residual chlorine after initial treatment. However, the degree to which chlorination can reduce microbial levels in a controlled setting (efficacy) or in a household setting (effectiveness) can vary as a function of chlorine characteristics, source water characteristics, and household conditions. To gain more understanding of these factors, we carried out an observational study within households in rural communities of northern coastal Ecuador. We found that the efficacy of chlorine treatment under controlled conditions was significantly better than its effectiveness when evaluated both by ability to meet microbiological safety standards and by log reductions. Water treated with chlorine achieved levels of microbial contamination considered safe for human consumption after 24 hours of storage in the household only 39 – 51% of the time, depending on chlorine treatment regimen. Chlorine treatment would not be considered protective against diarrheal disease according to WHO log reduction standards. Factors that explain the observed compromised effectiveness include: source water turbidity, source water baseline contamination levels, and in-home contamination. Water in 38% of the households that had low turbidity source water (< 10 NTU) met the safe water standard as compared with only 17% of the households that had high turbidity source water (> 10 NTU). A 10 MPN/100mL increase in baseline E. coli levels was associated with a 2.2% increase in failure to meet the E. colistandard. Higher mean microbial contamination levels in 54% of household samples in comparison to their matched controls, which is likely the result of in-home contamination during storage. Container characteristics (size of the container mouth) did not influence chlorine effectiveness. We found no significant differences between chlorine treatment regimens in ability to meet the safe water standards or in overall log reductions, although chlorine dosage did modify the effect of source conditions. These results underscore the importance of measuring both source water and household conditions to determine appropriate chlorine levels, as well as to evaluate the appropriateness of chlorine treatment and other point-of-use water quality improvement interventions. PMID:24561887

Household effectiveness vs. laboratory efficacy of point-of-use chlorination.

PubMed

Levy, Karen; Anderson, Larissa; Robb, Katharine A; Cevallos, William; Trueba, Gabriel; Eisenberg, Joseph N S

2014-05-01

Treatment of water at the household level offers a promising approach to combat the global burden of diarrheal diseases. In particular, chlorination of drinking water has been a widely promoted strategy due to persistence of residual chlorine after initial treatment. However, the degree to which chlorination can reduce microbial levels in a controlled setting (efficacy) or in a household setting (effectiveness) can vary as a function of chlorine characteristics, source water characteristics, and household conditions. To gain more understanding of these factors, we carried out an observational study within households in rural communities of northern coastal Ecuador. We found that the efficacy of chlorine treatment under controlled conditions was significantly better than its household effectiveness when evaluated both by ability to meet microbiological safety standards and by log reductions. Water treated with chlorine achieved levels of microbial contamination considered safe for human consumption after 24 h of storage in the household only 39-51% of the time, depending on chlorine treatment regimen. Chlorine treatment would not be considered protective against diarrheal disease according to WHO log reduction standards. Factors that explain the observed compromised effectiveness include: source water turbidity, source water baseline contamination levels, and in-home contamination. Water in 38% of the households that had low turbidity source water (<10 NTU) met the safe water standard as compared with only 17% of the households that had high turbidity source water (>10 NTU). A 10 MPN/100 mL increase in baseline Escherichia coli levels was associated with a 2.2% increase in failure to meet the E. coli standard. Higher mean microbial contamination levels were seen in 54% of household samples in comparison to their matched controls, which is likely the result of in-home contamination during storage. Container characteristics (size of the container mouth) did not influence chlorine effectiveness. We found no significant differences between chlorine treatment regimens in ability to meet the safe water standards or in overall log reductions, although chlorine dosage did modify the effect of source conditions. These results underscore the importance of measuring both source water and household conditions to determine appropriate chlorine levels, as well as to evaluate the appropriateness of chlorine treatment and other point-of-use water quality improvement interventions. Copyright © 2014 Elsevier Ltd. All rights reserved.

Subsurface information from eight wells drilled at the Idaho National Engineering Laboratory, southeastern Idaho

USGS Publications Warehouse

Goldstein, F.J.; Weight, W.D.

1982-01-01

The Idaho National Engineering Laboratory (INEL) covers about 890 square miles of the eastern Snake River Plain, in southeastern Idaho. The eastern Snake River Plain is a structural basin which has been filled with thin basaltic lava flows, rhyolitic deposits, and interbedded sediments. These rocks form an extensive ground-water reservoir known as the Snake River Plain aquifer. Six wells were drilled and two existing wells were deepened at the INEL from 1969 through 1974. Interpretation of data from the drilling program confirms that the subsurface is dominated by basalt flows interbedded with layers of sediment, cinders, and silicic volcanic rocks. Water levels in the wells show cyclic seasonal fluctuations of maximum water levels in winter and minimum water levels in mid-summer. Water levels in three wells near the Big Lost River respond to changes in recharge to the Snake River Plain aquifer from the Big Lost River. Measured water levels in multiple piezometers in one well indicate increasing pressure heads with depth. A marked decline in water levels in the wells since 1977 is attributed to a lack of recharge to the Snake River Plain aquifer.

Nitrates in drinking water and the risk of death from rectal cancer: does hardness in drinking water matter?

PubMed

Chang, Chih-Ching; Chen, Chih-Cheng; Wu, Deng-Chuang; Yang, Chun-Yuh

2010-01-01

The objectives of this study were to (1) examine the relationship between nitrate levels in public water supplies and increased risk of death from rectal cancer and (2) determine whether calcium (Ca) and magnesium (Mg) levels in drinking water might modify the effects of nitrate on development of rectal cancer. A matched case-control study was used to investigate the relationship between the risk of death from rectal cancer and exposure to nitrate in drinking water in Taiwan. All rectal cancer deaths of Taiwan residents from 2003 through 2007 were obtained from the Bureau of Vital Statistics of the Taiwan Provincial Department of Health. Controls were deaths from other causes and were pair-matched to the cases by gender, year of birth, and year of death. Information on the levels of nitrate-nitrogen (NO(3)-N), Ca, and Mg in drinking water was collected from Taiwan Water Supply Corporation (TWSC). The municipality of residence for cancer cases and controls was presumed to be the source of the subject's NO(3)-N, Ca, and Mg exposure via drinking water. Relative to individuals whose NO(3)-N exposure level was <0.38 ppm, the adjusted odds ratio (OR) (95% CI) for rectal cancer occurrence was 1.15 (1.01-1.32) for individuals who resided in municipalities served by drinking water with a NO(3)-N exposure > or =0.38 ppm. There was no apparent evidence of an interaction between drinking water NO(3)-N levels with low Mg intake via drinking water. However, evidence of a significant interaction was noted between drinking-water NO(3)-N concentrations and Ca intake via drinking water. Our findings showed that the correlation between NO(3)-N exposure and risk of rectal cancer development was influenced by Ca in drinking water. This is the first study to report effect modification by Ca intake from drinking water on the association between NO(3)-N exposure and risk of rectal cancer occurrence. Increased knowledge of the mechanistic interaction between Ca and NO(3)-N in reducing rectal cancer risk will aid in public policymaking and setting threshold standards.

Association between domestic water hardness, chlorine, and atopic dermatitis risk in early life: A population-based cross-sectional study.

PubMed

Perkin, Michael R; Craven, Joanna; Logan, Kirsty; Strachan, David; Marrs, Tom; Radulovic, Suzana; Campbell, Linda E; MacCallum, Stephanie F; McLean, W H Irwin; Lack, Gideon; Flohr, Carsten

2016-08-01

Domestic water hardness and chlorine have been suggested as important risk factors for atopic dermatitis (AD). We sought to examine the link between domestic water calcium carbonate (CaCO3) and chlorine concentrations, skin barrier dysfunction (increased transepidermal water loss), and AD in infancy. We recruited 1303 three-month-old infants from the general population and gathered data on domestic water CaCO3 (in milligrams per liter) and chlorine (Cl2; in milligrams per liter) concentrations from local water suppliers. At enrollment, infants were examined for AD and screened for filaggrin (FLG) skin barrier gene mutation status. Transepidermal water loss was measured on unaffected forearm skin. CaCO3 and chlorine levels were strongly correlated. A hybrid variable of greater than and less than median levels of CaCO3 and total chlorine was constructed: a baseline group of low CaCO3/low total chlorine (CaL/ClL), high CaCO3/low total chlorine (CaH/ClL), low CaCO3/high total chlorine (CaL/ClH) and high CaCO3/high total chlorine (CaH/ClH). Visible AD was more common in all 3 groups versus the baseline group: adjusted odds ratio (AOR) of 1.87 (95% CI, 1.25-2.80; P = .002) for the CaH/ClL group, AOR of 1.46 (95% CI, 0.97-2.21; P = .07) for the CaL/ClH, and AOR of 1.61 (95% CI, 1.09-2.38; P = .02) for the CaH/ClH group. The effect estimates were greater in children carrying FLG mutations, but formal interaction testing between water quality groups and filaggrin status was not statistically significant. High domestic water CaCO3 levels are associated with an increased risk of AD in infancy. The influence of increased total chlorine levels remains uncertain. An intervention trial is required to see whether installation of a domestic device to decrease CaCO3 levels around the time of birth can reduce this risk. Copyright © 2016 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

Modification of land-atmosphere interactions by CO2 effects

NASA Astrophysics Data System (ADS)

Lemordant, Leo; Gentine, Pierre

2017-04-01

Plant stomata couple the energy, water and carbon cycles. Increased CO2 modifies the seasonality of the water cycle through stomatal regulation and increased leaf area. As a result, the water saved during the growing season through higher water use efficiency mitigates summer dryness and the impact of potential heat waves. Land-atmosphere interactions and CO2 fertilization together synergistically contribute to increased summer transpiration. This, in turn, alters the surface energy budget and decreases sensible heat flux, mitigating air temperature rise. Accurate representation of the response to higher CO2 levels, and of the coupling between the carbon and water cycles are therefore critical to forecasting seasonal climate, water cycle dynamics and to enhance the accuracy of extreme event prediction under future climate.

Water-level changes induced by local and distant earthquakes at Long Valley caldera, California

USGS Publications Warehouse

Roeloffs, Evelyn A.; Sneed, Michelle; Galloway, Devin L.; Sorey, Michael L.; Farrar, Christopher D.; Howle, James F.; Hughes, J.

2003-01-01

Distant as well as local earthquakes have induced groundwater-level changes persisting for days to weeks at Long Valley caldera, California. Four wells open to formations as deep as 300 m have responded to 16 earthquakes, and responses to two earthquakes in the 3-km-deep Long Valley Exploratory Well (LVEW) show that these changes are not limited to weathered or unconsolidated near-surface rocks. All five wells exhibit water-level variations in response to earth tides, indicating they can be used as low-resolution strainmeters. Earthquakes induce gradual water-level changes that increase in amplitude for as long as 30 days, then return more slowly to pre-earthquake levels. The gradual water-level changes are always drops at wells LKT, LVEW, and CH-10B, and always rises at well CW-3. At a dilatometer just outside the caldera, earthquake-induced strain responses consist of either a step followed by a contractional strain-rate increase, or a transient contractional signal that reaches a maximum in about seven days and then returns toward the pre-earthquake value. The sizes of the gradual water-level changes generally increase with earthquake magnitude and decrease with hypocentral distance. Local earthquakes in Long Valley produce coseismic water-level steps; otherwise the responses to local earthquakes and distant earthquakes are indistinguishable. In particular, water-level and strain changes in Long Valley following the 1992 M7.3 Landers earthquake, 450 km distant, closely resemble those initiated by a M4.9 local earthquake on November 22, 1997, during a seismic swarm with features indicative of fluid involvement. At the LKT well, many of the response time histories are identical for 20 days after each earthquake, and can be matched by a theoretical solution giving the pore pressure as a function of time due to diffusion of a nearby, instantaneous, pressure drop. Such pressure drops could be produced by accelerated inflation of the resurgent dome by amounts too small to be detected by the two-color electronic distance-measuring network. Opening-mode displacement in the south moat, inferred to have followed a M4.9 earthquake on November 22, 1997, could also create extensional strain on the dome and lead to water-level changes similar to those following dome inflation. Contractional strain that could account for earthquake-induced water-level rises at the CW-3 well is inconsistent with geodetic observations. We instead attribute these water-level rises to diffusion of elevated fluid pressure localized in the south moat thermal aquifer. For hydraulic diffusivities appropriate to the upper few hundred meters at Long Valley, an influx of material at temperatures of 300°C can thermally generate pressure of 6 m of water or more, an order of magnitude larger than needed to account for the CW-3 water-level rises. If magma or hot aqueous fluid rises to within 1 km of the surface in the eastern part of the south moat, then hydraulic diffusivities are high enough to allow fluid pressure to propagate to CW-3 on the time scale observed. The data indicate that seismic waves from large distant earthquakes can stimulate upward movement of fluid in the hydrothermal system at Long Valley.

PPARβ/δ ameliorates fructose-induced insulin resistance in adipocytes by preventing Nrf2 activation.

PubMed

Barroso, Emma; Rodríguez-Rodríguez, Rosalía; Chacón, Matilde R; Maymó-Masip, Elsa; Ferrer, Laura; Salvadó, Laia; Salmerón, Emilio; Wabistch, Martin; Palomer, Xavier; Vendrell, Joan; Wahli, Walter; Vázquez-Carrera, Manuel

2015-05-01

We studied whether PPARβ/δ deficiency modifies the effects of high fructose intake (30% fructose in drinking water) on glucose tolerance and adipose tissue dysfunction, focusing on the CD36-dependent pathway that enhances adipose tissue inflammation and impairs insulin signaling. Fructose intake for 8 weeks significantly increased body and liver weight, and hepatic triglyceride accumulation in PPARβ/δ-deficient mice but not in wild-type mice. Feeding PPARβ/δ-deficient mice with fructose exacerbated glucose intolerance and led to macrophage infiltration, inflammation, enhanced mRNA and protein levels of CD36, and activation of the JNK pathway in white adipose tissue compared to those of water-fed PPARβ/δ-deficient mice. Cultured adipocytes exposed to fructose also exhibited increased CD36 protein levels and this increase was prevented by the PPARβ/δ activator GW501516. Interestingly, the levels of the nuclear factor E2-related factor 2 (Nrf2), a transcription factor reported to up-regulate Cd36 expression and to impair insulin signaling, were increased in fructose-exposed adipocytes whereas co-incubation with GW501516 abolished this increase. In agreement with Nrf2 playing a role in the fructose-induced CD36 protein level increases, the Nrf2 inhibitor trigonelline prevented the increase and the reduction in insulin-stimulated AKT phosphorylation caused by fructose in adipocytes. Protein levels of the well-known Nrf2 target gene quinone oxidoreductase 1 (Nqo1) were increased in water-fed PPARβ/δ-null mice, suggesting that PPARβ/δ deficiency increases Nrf2 activity; and this increase was exacerbated in fructose-fed PPARβ/δ-deficient mice. These findings indicate that the combination of high fructose intake and PPARβ/δ deficiency increases CD36 protein levels via Nrf2, a process that promotes chronic inflammation and insulin resistance in adipose tissue. Copyright © 2015 Elsevier B.V. All rights reserved.

Effect of chronic intracerebroventricular angiotensin II infusion on vasopressin release in rats

NASA Technical Reports Server (NTRS)

Sterling, G. H.; Chee, O.; Riggs, R. V.; Keil, L. C.

1980-01-01

The effects of the chronic infusion of angiotensin II into the lateral cerebral ventricle on the release of arginine vasopressin in rats are investigated. Rats were subjected to a continuous infusion of angiotensin at a rate of 1 microgram/h for five days, during which they were offered water, isotonic saline or hypertonic saline ad libitum or 40 ml water/day, and fluid intake, changes in body weight, plasma sodium ion concentrations and plasma and pituitary arginine vasopressin levels were measured. Angiotensin II is found to increase the fluid intake of rats given isotonic saline and decrease plasma sodium ion levels with no changes in plasma or pituitary arginine vasopressin in those given water or isotonic saline. However, in rats given hypertonic saline, plasma sodium concentrations remained at control levels while plasma vasopressin increased, and in water-restricted rats the effects of angiotensin II were intermediate. Results thus demonstrate that angiotensin II-stimulated arginine vasopressin release is reduced under conditions in which plasma sodium ion concentration becomes dilute, compatible with a central role of angiotensin in the regulation of salt and water balance.

Effects of assimilable organic carbon and free chlorine on bacterial growth in drinking water.

PubMed

Liu, Xiaolu; Wang, Jingqi; Liu, Tingting; Kong, Weiwen; He, Xiaoqing; Jin, Yi; Zhang, Bolin

2015-01-01

Assimilable organic carbon (AOC) is one of the most important factors affecting the re-growth of microorganisms in drinking water. High AOC concentrations result in biological instability, but disinfection kills microbes to ensure the safety of drinking water. Free chlorine is an important oxidizing agent used during the disinfection process. Therefore, we explored the combined effects of AOC and free chlorine on bacterial growth in drinking water using flow cytometry (FCM). The initial AOC concentration was 168 μg.L(-1) in all water samples. Without free chlorine, the concentrations of intact bacteria increased but the level of AOC decreased. The addition of sodium hypochlorite caused an increase and fluctuation in AOC due to the oxidation of organic carbon. The concentrations of intact bacteria decreased from 1.1 × 10(5) cells.mL(-1) to 2.6 × 10(4) cells.mL(-1) at an initial free chlorine dose of 0.6 mg.L(-1) to 4.8 × 10(4) cells.mL(-1) at an initial free chlorine dose of 0.3 mg.L(-1) due to free chlorine originating from sodium hypochlorite. Additionally, free chlorine might be more obviously affected AOC concentrations than microbial growth did. These results suggested that AOC and free chlorine might have combined effects on microbial growth. In this study, our results showed concentrations determined by FCM were higher than those by HPC, which indicated that some E. coli detected by FCM might not be detected using HPC in drinking water. The level of free chlorine might restrain the consumption of AOC by inhibiting the growth of E. coli; on the other hand, chlorination might increase the level of AOC, thereby increase the potential for microbial growth in the drinking water network.

Effects of Assimilable Organic Carbon and Free Chlorine on Bacterial Growth in Drinking Water

PubMed Central

Liu, Tingting; Kong, Weiwen; He, Xiaoqing; Jin, Yi; Zhang, Bolin

2015-01-01

Assimilable organic carbon (AOC) is one of the most important factors affecting the re-growth of microorganisms in drinking water. High AOC concentrations result in biological instability, but disinfection kills microbes to ensure the safety of drinking water. Free chlorine is an important oxidizing agent used during the disinfection process. Therefore, we explored the combined effects of AOC and free chlorine on bacterial growth in drinking water using flow cytometry (FCM). The initial AOC concentration was 168 μg.L-1 in all water samples. Without free chlorine, the concentrations of intact bacteria increased but the level of AOC decreased. The addition of sodium hypochlorite caused an increase and fluctuation in AOC due to the oxidation of organic carbon. The concentrations of intact bacteria decreased from 1.1×105 cells.mL-1 to 2.6×104 cells.mL-1 at an initial free chlorine dose of 0.6 mg.L-1 to 4.8×104 cells.mL-1 at an initial free chlorine dose of 0.3 mg.L-1 due to free chlorine originating from sodium hypochlorite. Additionally, free chlorine might be more obviously affected AOC concentrations than microbial growth did. These results suggested that AOC and free chlorine might have combined effects on microbial growth. In this study, our results showed concentrations determined by FCM were higher than those by HPC, which indicated that some E. coli detected by FCM might not be detected using HPC in drinking water. The level of free chlorine might restrain the consumption of AOC by inhibiting the growth of E. coli; on the other hand, chlorination might increase the level of AOC, thereby increase the potential for microbial growth in the drinking water network. PMID:26034988

Sustainable Management of Springs and Associated Wetlands in Aridland Regions: A Water Quality Perspective for Cibola National Forest, NM

NASA Astrophysics Data System (ADS)

Paffett, K.; Crossey, L. J.; Crowley, L.; Karlstrom, K. E.

2010-12-01

In the arid southwestern U.S., springs and their associated wetlands provide an opportunity for diverse ecosystems to flourish. With increasing encroachment, multiple-use requirements and increasing groundwater depletion, a better understanding of how the springs function is needed in order to properly manage the springs as a resource. Critical data on spring status (discharge patterns across seasons and water quality) are lacking for most springs. New strategies and environmental sensors can be employed to provide baseline information, as well as continuous data. We report here on systematic evaluation of a suite of springs of the Cibola National Forest in central New Mexico, including characteristics of discharge and water quality. The work is prompted by concerns on preservation of vital habitat for the Zuni Bluehead Sucker in portions of the Cibola National Forest. Spring occurrence includes a range of elevation (2000-2500m), vegetation type (arid grasslands to alpine wilderness), impact (livestock use, increased groundwater withdrawal, species of concern, and increased recreational use), and water quality (potable to saline). Many of the springs occur along fault structures, and are fed by groundwater from confined aquifer systems. Two levels of protocols are described: Level One for developing a baseline survey for water quality in managed lands (geospatial data, geologic map, systematic photography, discharge estimate and field-determined water quality parameters); and Level Two Impact Evaluation Monitoring (includes high-resolution geologic mapping, major ion chemistry, multiple sampling dates, and real-time autonomous logging of several parameters including temperature, pH, conductance and dissolved oxygen). Data collected from the surveys are stored in a geospatial repository to serve as background for future monitoring of the water resources in the area.

Iron-mediated changes in phytoplankton photosynthetic competence during SOIREE

NASA Astrophysics Data System (ADS)

Boyd, P. W.; Abraham, E. R.

Active fluorescence (fast repetition rate fluorometry, FRRF) was used to follow the photosynthetic response of the phytoplankton community during the 13-day Southern Ocean Iron RElease Experiment (SOIREE). This in situ iron enrichment was conducted in the polar waters of the Australasian-Pacific sector of the Southern Ocean in February 1999. Iron fertilisation of these high nitrate low chlorophyll (HNLC) waters resulted in an increase in the photosynthetic competence ( Fv/ Fm) of the resident cells from around 0.20 to greater than 0.60 (i.e. close to the theoretical maximum) by 10/11 days after the first enrichment. Although a significant iron-mediated response in Fv/ Fm was detected as early as 24 h after the initial fertilisation, the increase in Fv/ Fm to double ambient levels took 6 days. This response was five-fold slower than observed in iron enrichments (in situ and in vitro) in the HNLC waters of the subarctic and equatorial Pacific. Although little is known about the relationship between water temperature and Fv/ Fm, it is likely that low water temperatures — and possibly the deep mixed layer — were responsible for this slow response time. During SOIREE, the photosynthetic competence of the resident phytoplankton in iron-enriched waters increased at dissolved iron levels above 0.2 nM, suggesting that iron limitation was alleviated at this concentration. Increases in Fv/ Fm of cells within four algal size classes suggested that all taxa displayed a photosynthetic response to iron enrichment. Other physiological proxies of algal iron stress (such as flavodoxin levels in diatoms) exhibited different temporal trends to iron-enrichment than Fv/ Fm during the time-course of SOIREE. The relationship between Fv/ Fm, algal growth rate and such proxies in Southern Ocean waters is discussed.

Evaluating exposure of pedestrians to airborne contaminants associated with non-potable water use for pavement cleaning.

PubMed

Seidl, M; Da, G; Ausset, P; Haenn, S; Géhin, E; Moulin, L

2016-04-01

Climate change and increasing demography press local authorities to look after affordable water resources and replacement of drinking water for city necessities like street and pavement cleaning by more available raw water. Though, the substitution of drinking by non-drinking resources demands the evaluation of sanitary hazards. This article aims therefore to evaluate the contribution of cleaning water to the overall exposure of city dwellers in case of wet pavement cleaning using crossed physical, chemical and biological approaches. The result of tracer experiments with fluorescein show that liquid water content of the cleaning aerosol produced is about 0.24 g m(-3), rending possible a fast estimation of exposure levels. In situ analysis of the aerosol particles indicates a significant increase in particle number concentration and particle diameter, though without change in particle composition. The conventional bacterial analysis using total coliforms as tracer suggests that an important part of the contamination is issued from the pavement. The qPCR results show a more than 20-fold increase of background genome concentration for Escherichia coli and 10-fold increase for Enterococcus but a negligible contribution of the cleaning water. The fluorescence analysis of the cleaning aerosol confirms the above findings identifying pavement surface as the major contributor to aerosol organic load. The physical, chemical and microbiological approaches used make it possible to describe accurately the cleaning bioaerosol and to identify the existence of significantly higher levels of all parameters studied during the wet pavement cleaning. Though, the low level of contamination and the very short time of passage of pedestrian in the zone do not suggest a significant risk for the city dwellers. As the cleaning workers remain much longer in the impacted area, more attention should be paid to their chronic exposure.

Influence of Seasonality on the Genetic Diversity of Vibrio parahaemolyticus in New Hampshire Shellfish Waters as Determined by Multilocus Sequence Analysis

PubMed Central

Ellis, Crystal N.; Schuster, Brian M.; Striplin, Megan J.; Jones, Stephen H.; Whistler, Cheryl A.

2012-01-01

Risk of gastric infection with Vibrio parahaemolyticus increases with favorable environmental conditions and population shifts that increase prevalence of infective strains. Genetic analysis of New Hampshire strains revealed a unique population with some isolates similar to outbreak-causing strains and high-level diversity that increased as waters warmed. PMID:22407686

Influence of seasonality on the genetic diversity of Vibrio parahaemolyticus in New Hampshire shellfish waters as determined by multilocus sequence analysis.

PubMed

Ellis, Crystal N; Schuster, Brian M; Striplin, Megan J; Jones, Stephen H; Whistler, Cheryl A; Cooper, Vaughn S

2012-05-01

Risk of gastric infection with Vibrio parahaemolyticus increases with favorable environmental conditions and population shifts that increase prevalence of infective strains. Genetic analysis of New Hampshire strains revealed a unique population with some isolates similar to outbreak-causing strains and high-level diversity that increased as waters warmed.

Unregulated private wells in the Republic of Ireland: consumer awareness, source susceptibility and protective actions.

PubMed

Hynds, Paul D; Misstear, Bruce D; Gill, Laurence W

2013-09-30

While the safety of public drinking water supplies in the Republic of Ireland is governed and monitored at both local and national levels, there are currently no legislative tools in place relating to private supplies. It is therefore paramount that private well owners (and users) be aware of source specifications and potential contamination risks, to ensure adequate water quality. The objective of this study was to investigate the level of awareness among private well owners in the Republic of Ireland, relating to source characterisation and groundwater contamination issues. This was undertaken through interviews with 245 private well owners. Statistical analysis indicates that respondents' source type significantly influences owner awareness, particularly regarding well construction and design parameters. Water treatment, source maintenance and regular water quality testing are considered the three primary "protective actions" (or "stewardship activities") to consumption of contaminated groundwater and were reported as being absent in 64%, 72% and 40% of cases, respectively. Results indicate that the level of awareness exhibited by well users did not significantly affect the likelihood of their source being contaminated (source susceptibility); increased awareness on behalf of well users was associated with increased levels of protective action, particularly among borehole owners. Hence, lower levels of awareness may result in increased contraction of waterborne illnesses where contaminants have entered the well. Accordingly, focused educational strategies to increase awareness among private groundwater users are advocated in the short-term; the development and introdiction of formal legislation is recommended in the long-term, including an integrated programme of well inspections and risk assessments. Copyright © 2013 Elsevier Ltd. All rights reserved.

Drinking water systems, hydrology, and childhood gastrointestinal illness in central and northern Wisconsin

USDA-ARS?s Scientific Manuscript database

Background: Current United States drinking water regulations create areas with different levels of water quality. Municipalities accessing untreated groundwater and households with unmonitored private wells may be at increased risk for acquiring waterborne disease. Objectives: The study investigat...

BIOLOGICAL FILTRATION FOR THE NITRIFICATION OF EXCESSIVE LEVELS OF FREE AMMONIA

EPA Science Inventory

Ammonia in source waters can cause water treatment and distribution system problems. Research on the presence of ammonia in drinking water distribution systems for example has suggested some correlation between excess ammonia and increased biological activity (Servais, 1995; Wilc...

Evaluation of availability of water from drift aquifers near the Pomme de Terre and Chippewa rivers, western Minnesota

USGS Publications Warehouse

Delin, G.N.

1987-01-01

The model was used to simulate the effects of below-normal precipitation (drought) and hypothetical increases in ground-water development. Model results indicate that reduced recharge and increased pumping during a three-year extended drought probably would lower water levels 2 to 6 feet regionally in the surficial aquifer and in the Appleton and Benson-middle aquifers and as much as 11 feet near aquifer boundaries. Ground-water discharge to the Pomme de Terre and Chippewa Rivers in the modeled area probably would be reduced during the simulated drought by 15.2 and 7.4 cubic feet per second, respectively, compared to 1982 conditions. The addition of 30 hypothetical wells in the Benson-middle aquifer near Benson, pumping a total of 810 million gallons per year, resulted in water-level declines of as much as 1.3 and 2.7 feet in the surficial and Benson-middle aquifers, respectively. The addition of 28 hypothetical wells in the Appleton aquifer east and southeast of Appleton, pumping a total of 756 million gallons per year, lowered water levels in the surficial and Appleton confined aquifers as much as 5 feet.

Towards health impact assessment of drinking-water privatization--the example of waterborne carcinogens in North Rhine-Westphalia (Germany).

PubMed Central

Fehr, Rainer; Mekel, Odile; Lacombe, Martin; Wolf, Ulrike

2003-01-01

Worldwide there is a tendency towards deregulation in many policy sectors - this, for example, includes liberalization and privatization of drinking-water management. However, concerns about the negative impacts this might have on human health call for prospective health impact assessment (HIA) on the management of drinking-water. On the basis of an established generic 10-step HIA procedure and on risk assessment methodology, this paper aims to produce quantitative estimates concerning health effects from increased exposure to carcinogens in drinking-water. Using data from North Rhine-Westphalia in Germany, probabilistic estimates of excess lifetime cancer risk, as well as estimates of additional cases of cancer from increased carcinogen exposure levels are presented. The results show how exposure to contaminants that are strictly within current limits could increase cancer risks and case-loads substantially. On the basis of the current analysis, we suggest that with uniform increases in pollutant levels, a single chemical (arsenic) is responsible for a large fraction of expected additional risk. The study also illustrates the uncertainty involved in predicting the health impacts of changes in water quality. Future analysis should include additional carcinogens, non-cancer risks including those due to microbial contamination, and the impacts of system failures and of illegal action, which may be increasingly likely to occur under changed management arrangements. If, in spite of concerns, water is privatized, it is particularly important to provide adequate surveillance of water quality. PMID:12894324

RIVER LEVEL ESTIMATION USING ARTIFICIAL NEURAL NETWORK FOR URBAN SMALL RIVER IN TIDAL REACH

NASA Astrophysics Data System (ADS)

Takasaki, Tadakatsu; Kawamura, Akira; Amaguchi, Hideo

Prediction of water level in small rivers is great interest for flood control in an urban area located in the river mouth. The tidal river water level is affected by not only flood discharge but also tide, atmospheric pressure, wind direction and speed. We propose a method of estimating river water level considering these factors using an artificial neural network model for the Kanda River located in the center of Tokyo. The effects by those factors are quantitatively investigated. As for the effects by the atmospheric pressure, river water level rises about 7cm per 5hPa increase of the pressure regardless of river discharge under the conditions of 1m/s wind speed and north wind direction. The accurate rating curve for the tidal river is finally obtained.

Monitoring duration and extent of storm-surge and flooding in Western Coastal Louisiana marshes with Envisat ASAR data

USGS Publications Warehouse

Ramsey, E.; Lu, Z.; Suzuoki, Y.; Rangoonwala, A.; Werle, D.

2011-01-01

Inundation maps of coastal marshes in western Louisiana were created with multitemporal Envisat Advanced Synthetic Aperture (ASAR) scenes collected before and during the three months after Hurricane Rita landfall in September 2005. Corroborated by inland water-levels, 7 days after landfall, 48% of coastal estuarine and palustrine marshes remained inundated by storm-surge waters. Forty-five days after landfall, storm-surge inundated 20% of those marshes. The end of the storm-surge flooding was marked by an abrupt decrease in water levels following the passage of a storm front and persistent offshore winds. A complementary dramatic decrease in flood extent was confirmed by an ASAR-derived inundation map. In nonimpounded marshes at elevations <;80 cm, storm-surge waters rapidly receded while slower recession was dominantly associated with impounded marshes at elevations >;80 cm during the first month after Rita landfall. After this initial period, drainage from marshes-especially impounded marshes-was hastened by the onset of offshore winds. Following the abrupt drops in inland water levels and flood extent, rainfall events coinciding with increased water levels were recorded as inundation re-expansion. This postsurge flooding decreased until only isolated impounded and palustrine marshes remained inundated. Changing flood extents were correlated to inland water levels and largely occurred within the same marsh regions. Trends related to incremental threshold increases used in the ASAR change-detection analyses seemed related to the preceding hydraulic and hydrologic events, and VV and HH threshold differences supported their relationship to the overall wetland hydraulic condition.

How much will be economic impact of climate change on water resources? A Meta-Analytic Review of previous literature

NASA Astrophysics Data System (ADS)

Yoshikawa, S.; Iseri, Y.; Kanae, S.

2016-12-01

Water resources is vital in social and economic activities. Total global water use is increasing, mainly due to economic and population growth in developing countries. It has one of risk with high agreement and robust evidence that freshwater-related risks of climate change increase significantly with increasing greenhouse gas concentrations. It is difficult to compare the risk with other field risk (e.g. agriculture, forestry, sea level rise) for considering both adaptation and mitigation policy with the level of decision makers and public servants. Economic impacts of climate change on water scarcity has been estimated by economic researchers. We have no certainty at all about integration between hydrological and economical fields on global scale. In this study, we highlight key concerns about conventional estimations of economic impact on water resources through meta-analysis. The economic impact on water resource in same base year using consumer price index is shown with increase in the global mean temperature. We clarified four concerns which are involved in 1) classification of economic mechanism, 2) estimated items of economic impact, 3) difference in estimating equations, and 4) definition of parameters related with economic impact of climate change. This study would be essential to next challenge as transdisciplinary research between hydrologic and economic fields.

Ground-water, surface-water, and water-chemistry data, Black Mesa area, northeastern Arizona, 1997

USGS Publications Warehouse

Littin, Gregory R.; Baum, Bradley M.; Truini, Margot

1999-01-01

The Black Mesa monitoring program is designed to document long-term effects of ground-water from the N aquifer by industrial and municipal users. The N aquifer is the major source of water in the 5,400-square-mile Black Mesa area, and the ground water occurs under confined and unconfined conditions. Monitoring activities include continuous and periodic measurements of (1) ground-water pumpage from the confined and unconfined parts of the aquifer, (2) ground-water levels in the confined and unconfined parts of the aquifer, (3) surface-water discharge, and (4) chemistry of the ground water and surface water. In 1997, ground-water withdrawals for industrial and municipal use totaled about 7,090 acre-feet, which is less than a 1-percent increase from 1996. Pumpage from the confined part of the aquifer increased by about 2 percent to 5,510 acre-feet, and pumpage from the unconfined part of the aquifer decreased by about 4 percent to 1,580 acre-feet. Water-level declines in the confined part during 1997 were recorded in 5 of 12 wells; however, the median change was a rise of about 0.2 foot as opposed to a decline of 2.8 feet for 1996. Water-level declines in the unconfined part were recorded in 7 of 15 wells, and the median change was 0.0 foot in 1997 as opposed to a decline of 0.5 foot in 1996. The low-flow discharge at the Moenkopi streamflow-gaging station ranged from 1.6 to 2.0 cubic feet per second in 1997. Streamflow-discharge measurements also were made at Laguna Creek, Dinnebito Wash, and Polacca Wash during 1997. The low-flow discharge ranged from 2.3 to 4.2 cubic feet per second at Laguna Creek, 0.44 to 0.48 cubic foot per second at Dinnebito Wash, and 0.15 to 0.26 cubic foot per second at Polacca Wash. Discharge was measured at three springs. Discharge from Moenkopi School Spring increased by about 3 gallons per minute from the measurement in 1996. Discharge from an unnamed spring near Dennehotso increased by 9.9 gallons per minute from the measurement made in 1996; however, discharge decreased slightly at Burro Spring. Regionally, long-term water-chemistry data for wells and springs have remained stable. Locally, water-chemistry data for some wells have shown marked increases in concentrations of major constituents.

Effects of Aquifer Development and Changes in Irrigation Practices on Ground-Water Availability in the Santa Isabel Area, Puerto Rico

USGS Publications Warehouse

Kuniansky, Eve L.; Gómez-Gómez, Fernando; Torres-Gonzalez, Sigfredo

2003-01-01

The alluvial aquifer in the area of Santa Isabel is located within the South Coastal Plain aquifer of Puerto Rico. Variations in precipitation, changes in irrigation practices, and increasing public-supply water demand have been the primary factors controlling water-level fluctuations within the aquifer. Until the late 1970s, much of the land in the study area was irrigated using inefficient furrow flooding methods that required large volumes of both surface and ground water. A gradual shift in irrigation practices from furrow systems to more efficient micro-drip irrigation systems occurred between the late 1970s and the late 1980s. Irrigation return flow from the furrow-irrigation systems was a major component of recharge to the aquifer. By the early 1990s, furrow-type systems had been replaced by the micro-drip irrigation systems. Water levels declined about 20 feet in the aquifer from 1985 until present (February 2003). The main effect of the changes in agricultural practices is the reduction in recharge to the aquifer and total irrigation withdrawals. Increases in ground-water withdrawals for public supply offset the reduction in ground-water withdrawals for irrigation such that the total estimated pumping rate in 2003 was only 8 percent less than in 1987. Micro-drip irrigation resulted in the loss of irrigation return flow to the aquifer. These changes resulted in lowering the water table below sea level over most of the Santa Isabel area. By 2002, lowering of the water table reversed the natural discharge along the coast and resulted in the inland movement of seawater, which may result in increased salinity of the aquifer, as had occurred in other parts of the South Coastal Plain. Management alternatives for the South Coastal Plain aquifer in the vicinity of Santa Isabel include limiting groundwater withdrawals or implementing artificial recharge measures. Another alternative for the prevention of saltwater intrusion is to inject freshwater or treated sewage effluent into wells along the coast. A digital ground-water flow model was developed to provide information for water managers to evaluate some of these alternatives. After calibration of the ground-water model to historical data, four simulations of ground-water management strategies were performed: ground-water conservation, surface infiltration over existing agricultural fields, or infiltration along streams and canals, or injection wells along the coast. Simulations of four alternative water management strategies indicate that current condition of water levels below sea level near the coast can be reversed to raise water levels above sea level by either: (1) about a 27 percent reduction in 2003 ground-water withdrawal rates; (2) application of about 1,700 million gallons per year of artificial recharge over more than half of the current agricultural areas; (3) injection of about 3 million gallons per day (1,095 million gallons per year) of freshwater or treated wastewater in wells distributed along the coast; (4) injection of about 3.5 million gallons per day (1,280 million gallons per year) of freshwater or treated wastewater in wells distributed along canals and streams.

Water quality in select regions of Cauvery Delta River basin, southern India, with emphasis on monsoonal variation.

PubMed

Solaraj, Govindaraj; Dhanakumar, Selvaraj; Murthy, Kuppuraj Rutharvel; Mohanraj, Rangaswamy

2010-07-01

Delta regions of the Cauvery River basin are one of the significant areas of rice production in India. In spite of large-scale utilization of the river basin for irrigation and drinking purposes, the lack of appropriate water management has seemingly deteriorated the water quality due to increasing anthropogenic activities. To assess the extent of deterioration, physicochemical characteristics of surface water were analyzed monthly in select regions of Cauvery Delta River basin, India, during July 2007 to December 2007. Total dissolved solids, chemical oxygen demand, and phosphate recorded maximum levels of 1,638, 96, and 0.43 mg/l, respectively, exceeding the permissible levels at certain sampling stations. Monsoonal rains in Cauvery River basin and the subsequent increase in river flow rate influences certain parameters like dissolved solids, phosphate, and dissolved oxygen. Agricultural runoff from watershed, sewage, and industrial effluents are suspected as probable factors of water pollution.

Two-dimensional ground-water flow model of the Cretaceous aquifer system of Lee County and vicinity, Mississippi

USGS Publications Warehouse

Kernodle, John Michael

1981-01-01

A two-dimensional ground-water flow model of the Eutaw-McShan and Gordo aquifers in the area of Lee County, Miss., was successfully calibrated and verified using data from six long-term observation wells and two intensive studies of areal water levels. The water levels computed by the model were found to be most sensitive to changes in simulated aquifer hydraulic conductivity and to changes in head in the overlying Coffee Sand aquifer. The two-dimensional model performed reasonably well in simulating the aquifer system except possibly in southern Lee County and southward where a clay bed at the top of the Gordo Formation partially isolated the Gordo from the overlying Eutaw-McShan aquifer. The verified model was used to determine theoretical aquifer response to increased ground-water withdrawal to the year 2000. Two estimated rates of increase and five possible well field locations were examined. (USGS)

The effects of season and sand mining activities on thermal regime and water quality in a large shallow tropical lake.

PubMed

Sharip, Zati; Zaki, Ahmad Taqiyuddin Ahmad

2014-08-01

Thermal structure and water quality in a large and shallow lake in Malaysia were studied between January 2012 and June 2013 in order to understand variations in relation to water level fluctuations and in-stream mining activities. Environmental variables, namely temperature, turbidity, dissolved oxygen, pH, electrical conductivity, chlorophyll-A and transparency, were measured using a multi-parameter probe and a Secchi disk. Measurements of environmental variables were performed at 0.1 m intervals from the surface to the bottom of the lake during the dry and wet seasons. High water level and strong solar radiation increased temperature stratification. River discharges during the wet season, and unsustainable sand mining activities led to an increased turbidity exceeding 100 NTU, and reduced transparency, which changed the temperature variation and subsequently altered the water quality pattern.

Effect of addition of ripe bananas on some physico-chemical properties of maize 'extract'.

PubMed

Okezie, U; Akanbi, C T; Otunola, E T; Adeyemi, I A

2003-11-01

Flour mixes obtained by the addition of banana pulp in various proportions (0-50%) to maize 'extracts' were evaluated for some quality characteristics. All the mixes had significantly lower values of crude protein, fat and water-holding capacity. Gelation, however, significantly increased the water-holding capacity in all cases. The ash content, titratable acidity and total sugars increased tremendously with an increase in the level of banana substitution. While both Adam's consistency values and equilibrium moisture content decreased with an increase in the level of banana substitution, the syneresis values did not show any consistent pattern. The consistently low moisture content and the results of the moisture sorption isotherms suggest a good storage stability of all the mixes, especially when kept under conditions of water activity of 0.30 and below, and their possible suitability for baked products.

Social Justice and Water Issues in the 21st Century

NASA Astrophysics Data System (ADS)

Boyer, E. W.; Fowler, L.

2014-12-01

Water resources are critical to human and ecosystem health. Population growth, land use changes, and environmental changes are intensifying stresses on water resources throughout the world. Increasing and competing demands for water require decision-making about water management and allocation to support multiple and competing uses. Further, climatic variability and periods of floods and drought are threats to humans, ecosystems, and economies. Inequalities in the distribution of water resources and access to safe and affordable water abound, greatly affecting communities. Here, we provide examples aiming to bridge the gap between social justice and environmental science literacy through college-level course work in watershed hydrology and management and in water law and policy. Examples are drawn considering water use, water pollution, and water governance. For example, we explore relationships between water governance (e.g., via land ownership and policy), land use (e.g., food production), water use (e.g., irrigation of agricultural lands), water pollution (e.g., pollution of surface and ground waters with agricultural nutrient runoff), and societal well-being (e.g., effects on communities). Course outcomes include increased social awareness, increased knowledge of water resources, and increased scientific literacy.

Vasopressin and angiotensin II in reflex regulation of ACTH, glucocorticoids, and renin: effect of water deprivation

NASA Technical Reports Server (NTRS)

Brooks, V. L.; Keil, L. C.

1992-01-01

Angiotensin II (ANG II) and vasopressin participate in baroreflex regulation of adrenocorticotropic hormone (ACTH), glucocorticoid, and renin secretion. The purpose of this study was to determine whether this participation is enhanced in water-deprived dogs, with chronically elevated plasma ANG II and vasopressin levels, compared with water-replete dogs. The baroreflex was assessed by infusing increasing doses of nitroprusside (0.3, 0.6, 1.5, and 3.0 micrograms.kg-1.min-1) in both groups of animals. To quantitate the participation of ANG II and vasopressin, the dogs were untreated or pretreated with the competitive ANG II antagonist saralasin, a V1-vasopressin antagonist, or combined V1/V2-vasopressin antagonist, either alone or in combination. The findings were as follows. 1) Larger reflex increases in ANG II, vasopressin, and glucocorticoids, but not ACTH, were produced in water-deprived dogs compared with water-replete dogs. 2) ANG II blockade blunted the glucocorticoid and ACTH responses to hypotension in water-deprived dogs, but not water-replete dogs. In contrast, vasopressin blockade reduced the ACTH response only in water-replete dogs. 3) Vasopressin or combined vasopressin and ANG II blockade reduced the plasma level of glucocorticoids related either to the fall in arterial pressure or to the increase in plasma ACTH concentration in water-replete dogs, and this effect was enhanced in water-deprived dogs. 4) In both water-deprived and water-replete animals, saralasin and/or a V1-antagonist increased the renin response to hypotension, but a combined V1/V2-antagonist did not. These results reemphasize the importance of endogenous ANG II and vasopressin in the regulation of ACTH, glucocorticoid, and renin secretion.(ABSTRACT TRUNCATED AT 250 WORDS).

Broken Chains: The Effect of Ocean Acidification on Bivalve and Echinoid Development

NASA Astrophysics Data System (ADS)

Richardson, K.

2016-12-01

Global warming is one of the most urgent issues facing the interconnected systems of our planet. One important impact of global warming is ocean acidification, which is a change in the pH of the oceans due to increased levels of carbon dioxide in the atmosphere. This can harm ocean life in many ways, including the disintegration of reef structures and the weakening of many types of sea animals' shells. The purpose of this project is to assess the efficacy of a novel method of raising the pH of increasingly acidic ocean waters. The experiment was set up with water of varying pH levels. There were three different experiment groups, including current ocean water (pH 8.1), increased acidity ocean water (pH 7.5), and an increased acidity ocean water with an activated carbon filter (pH 7.5). Six bivalve shells were placed in each solution . Mass loss data was taken from bivalve shells every three days over the course of thirty days (for a total of ten measurements). I hypothesized that the carbon filter would improve the pH of the ocean water (by raising the pH from 7.5) to that of normal ocean water (pH 8.1). The data showed that while the acidic ocean water shell's weight decreased (by 13%), the acidic water with the filter and current ocean water decreased by 0.3% and 0.5%, respectively. Overall, the activated carbon filter decreased the amount of weight change from the acidic water. The data is applicable to helping solve ocean acidification - activated charcoal greatly improved the effects of very acidic ocean water, which could be used in the future to help offset the impact of ocean acidification on its creatures.

76 FR 37663 - Endangered and Threatened Wildlife and Plants; Designation of Critical Habitat for Tumbling Creek...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-06-28

... that the species requires adequate water quality, water quantity, water flow, a stable stream channel, minimal sedimentation, and energy input from the guano of bats, particularly gray bats (Myotis grisescens... water levels on Bull Shoals Reservoir (such as increased sedimentation or bank erosion from backwater...

Detection and Measurement of Land Subsidence Using Global Positioning System Surveying and Interferometric Synthetic Aperture Radar, Coachella Valley, California, 1996-2005

USGS Publications Warehouse

Sneed, Michelle; Brandt, Justin T.

2007-01-01

Land subsidence associated with ground-water-level declines has been investigated by the U.S. Geological Survey in the Coachella Valley, California, since 1996. Ground water has been a major source of agricultural, municipal, and domestic supply in the valley since the early 1920s. Pumping of ground water resulted in water-level declines as large as 15 meters (50 feet) through the late 1940s. In 1949, the importation of Colorado River water to the southern Coachella Valley began, resulting in a reduction in ground-water pumping and a recovery of water levels during the 1950s through the 1970s. Since the late 1970s, demand for water in the valley has exceeded deliveries of imported surface water, resulting in increased pumping and associated ground-water-level declines and, consequently, an increase in the potential for land subsidence caused by aquifer-system compaction. Global Positioning System (GPS) surveying and interferometric synthetic aperture radar (InSAR) methods were used to determine the location, extent, and magnitude of the vertical land-surface changes in the southern Coachella Valley. GPS measurements made at 13 geodetic monuments in 1996 and in 2005 in the southern Coachella Valley indicate that the elevation of the land surface had a net decline of 333 to 22 millimeters ?58 millimeters (1.1 to 0.07 foot ?0.19 foot) during the 9-year period. Changes at 10 of the 13 monuments exceeded the maximum uncertainty of ?58 millimeters (?0.19 foot) at the 95-percent confidence level, indicating that subsidence occurred at these monuments between June 1996 and August 2005. GPS measurements made at 20 geodetic monuments in 2000 and in 2005 indicate that the elevation of the land surface changed -312 to +25 millimeters ?42 millimeters (-1.0 to +0.08 foot ?0.14 foot) during the 5-year period. Changes at 14 of the 20 monuments exceeded the maximum uncertainty of ?42 millimeters (?0.14 foot) at the 95-percent confidence level, indicating that subsidence occurred at these monuments between August 2000 and August 2005. Eight of the fourteen monuments for which subsidence rates could be compared indicate that subsidence rates increased by as much as a factor of 10 between 2000 and 2005 compared with subsidence rates before 2000. InSAR measurements made between May 7, 2003, and September 25, 2005, indicate that land subsidence, ranging from about 75 to 180 millimeters (0.25 to 0.59 foot), occurred in three areas of the Coachella Valley: near Palm Desert, Indian Wells, and La Quinta; the equivalent subsidence rates range from about 3 to more than 6 mm/month (0.01 to 0.02 ft/month). The subsiding areas near Palm Desert, Indian Wells, and La Quinta were previously identified using InSAR measurements for 1996-2000, which indicated that about 35 to 150 mm (0.11 to 0.49 ft) of subsidence occurred during the four-year period; the equivalent subsidence rates range from about 1 to 3 mm/month (0.003 to 0.01 ft/month). Comparison of the InSAR results indicates that subsidence rates have increased 2 to 4 times since 2000 in these three areas. Water-level measurements made at wells near the subsiding monuments and in the three subsiding areas generally indicated that the water levels fluctuated seasonally and declined annually between 1996 and 2005; some water levels in 2005 were at the lowest levels in their recorded histories. The coincident areas of subsidence and declining water levels suggest that aquifer-system compaction may be causing subsidence. If the stresses imposed by the historically lowest water levels exceeded the preconsolidation stress, the aquifer-system compaction and associated land subsidence may be permanent. Although the localized character of the subsidence signals is typical of the type of subsidence characteristically caused by localized ground-water pumping, the subsidence may also be related to tectonic activity in the valley.

Estimation of solar collector area for water heating in buildings of Malaysia

NASA Astrophysics Data System (ADS)

Manoj Kumar, Nallapaneni; Sudhakar, K.; Samykano, M.

2018-04-01

Solar thermal energy (STE) utilization for water heating at various sectorial levels became popular and still growing especially for buildings in the residential area. This paper aims to study and identify the solar collector area needed based on the user requirements in an efficient manner. A step by step mathematical approach is followed to estimate the area in Sq. m. Four different cases each having different hot water temperatures (45°, 50°C, 55°C, and 60°C) delivered by the solar water heating system (SWHS) for typical residential application at Kuala Lumpur City, Malaysia is analysed for the share of hot and cold water mix. As the hot water temperature levels increased the share of cold water mix is increased to satisfy the user requirement temperature, i.e. 40°C. It is also observed that as the share of hot water mix is reduced, the collector area can also be reduced. Following this methodology at the installation stage would help both the user and installers in the effective use of the solar resource.

Utilization of LANDSAT data for water quality surveys in the Choptank River

NASA Technical Reports Server (NTRS)

Johnson, J. M.; Cressy, P.; Dallam, W. C.

1975-01-01

Computer processing of LANDSAT-1 multispectral digital data demonstrated the applicability of remotely sensed data to water quality survey in the Choptank River. Water classes derived by automated analysis correlate to river nuisance levels of chlorophyll a and sediment loading as defined by the Maryland Department of Water Resources and the U.S. Corps of Engineers. Results indicate that an increase in chlorophyll a concentration corresponds, relative to MSS 5, to decreases in 4 and increases in 6 relative to the trends with increasing sediment load. It appears that for the purpose of water quality analysis, under favorable atmospheric conditions, only MSS 4, 5 and 6 are necessary.

Mercury contamination level and speciation inventory in Lakes Titicaca & Uru-Uru (Bolivia): Current status and future trends.

PubMed

Guédron, S; Point, D; Acha, D; Bouchet, S; Baya, P A; Tessier, E; Monperrus, M; Molina, C I; Groleau, A; Chauvaud, L; Thebault, J; Amice, E; Alanoca, L; Duwig, C; Uzu, G; Lazzaro, X; Bertrand, A; Bertrand, S; Barbraud, C; Delord, K; Gibon, F M; Ibanez, C; Flores, M; Fernandez Saavedra, P; Ezpinoza, M E; Heredia, C; Rocha, F; Zepita, C; Amouroux, D

2017-12-01

Aquatic ecosystems of the Bolivian Altiplano (∼3800 m a.s.l.) are characterized by extreme hydro-climatic constrains (e.g., high UV-radiations and low oxygen) and are under the pressure of increasing anthropogenic activities, unregulated mining, agricultural and urban development. We report here a complete inventory of mercury (Hg) levels and speciation in the water column, atmosphere, sediment and key sentinel organisms (i.e., plankton, fish and birds) of two endorheic Lakes of the same watershed differing with respect to their size, eutrophication and contamination levels. Total Hg (THg) and monomethylmercury (MMHg) concentrations in filtered water and sediment of Lake Titicaca are in the lowest range of reported levels in other large lakes worldwide. Downstream, Hg levels are 3-10 times higher in the shallow eutrophic Lake Uru-Uru than in Lake Titicaca due to high Hg inputs from the surrounding mining region. High percentages of MMHg were found in the filtered and unfiltered water rising up from <1 to ∼50% THg from the oligo/hetero-trophic Lake Titicaca to the eutrophic Lake Uru-Uru. Such high %MMHg is explained by a high in situ MMHg production in relation to the sulfate rich substrate, the low oxygen levels of the water column, and the stabilization of MMHg due to abundant ligands present in these alkaline waters. Differences in MMHg concentrations in water and sediments compartments between Lake Titicaca and Uru-Uru were found to mirror the offset in MMHg levels that also exist in their respective food webs. This suggests that in situ MMHg baseline production is likely the main factor controlling MMHg levels in fish species consumed by the local population. Finally, the increase of anthropogenic pressure in Lake Titicaca may probably enhance eutrophication processes which favor MMHg production and thus accumulation in water and biota. Copyright © 2017 Elsevier Ltd. All rights reserved.

Assessment of yeast as a dietary additive on haematology and water quality of common carp in a recirculating aquaculture system

NASA Astrophysics Data System (ADS)

Goran, Siraj Muhammed Abdulla; Omar, Samad Sofy; Anwer, Ayub Youns

2017-09-01

Feeding experiment was accomplished at the Aquaculture unit (Close system), Grdarasha station, Agriculture College, University of Salahaddin, Erbil, Kurdistan Region, to investigate different levels of Aquagrow E (AGEY) brewer's yeast cell Saccharomyces cerevisiae on the haematological and water quality of common carp fingerlings Cyprinus carpio. The basal diet was formulated to contain 34% protein and 10% lipid and the dietary treatments were supplemented with 0.5%, 1% and 1.5% of AGEY diet. A total of 180 Common carp (10.30 ± 0.27 g) fed on experimental diets for 10 weeks. Water quality assessment for well water and pond water for rearing Cyprinus carpio in cage system conducted weekly, while some parameters including pH, EC, water temperature and DO were monitored daily during the entire periods of study. Values of total hardness, alkalinity, ammonia and nitrate for studied water samples were within normal ranges for rearing Cyprinus carpio. Mean concentration of GPT, GOT and Glucose were 104 to 170 U/L, 1371 to 3308 U/L and 34 to 63mg/dl respectively, moreover, highest levels were observed in treatments with higher concentrations of yeast in its food except for blood sugar. Slight variation in lipase enzyme were found between control and treatment groups, while levels of amylase enzyme were increased toward cages with higher levels of yeast until T1 and then decreased toward T3. Total protein levels were increased to toward higher levels of yeast in food of Cyprinus carpio fish. Haematological results showed highest levels of WBC and platelets in treatments cages than control group. Levels of RBCs and hemoglobin were highest in treatment group 1 with 0.5%of yeast than treatments higher yeast concentrations. Significant correlation was found in haematological parameters between control and treatments.

Fog interception by Sequoia sempervirens (D. Don) crowns decouples physiology from soil water deficit.

PubMed

Simonin, Kevin A; Santiago, Louis S; Dawson, Todd E

2009-07-01

Although crown wetting events can increase plant water status, leaf wetting is thought to negatively affect plant carbon balance by depressing photosynthesis and growth. We investigated the influence of crown fog interception on the water and carbon relations of juvenile and mature Sequoia sempervirens trees. Field observations of mature trees indicated that fog interception increased leaf water potential above that of leaves sheltered from fog. Furthermore, observed increases in leaf water potential exceeded the maximum water potential predicted if soil water was the only available water source. Because field observations were limited to two mature trees, we conducted a greenhouse experiment to investigate how fog interception influences plant water status and photosynthesis. Pre-dawn and midday branchlet water potential, leaf gas exchange and chlorophyll fluorescence were measured on S. sempervirens saplings exposed to increasing soil water deficit, with and without overnight canopy fog interception. Sapling fog interception increased leaf water potential and photosynthesis above the control and soil water deficit treatments despite similar dark-acclimated leaf chlorophyll fluorescence. The field observations and greenhouse experiment show that fog interception represents an overlooked flux into the soil-plant-atmosphere continuum that temporarily, but significantly, decouples leaf-level water and carbon relations from soil water availability.

Recharge characteristics of an unconfined aquifer from the rainfall-water table relationship

NASA Astrophysics Data System (ADS)

Viswanathan, M. N.

1984-02-01

The determination of recharge levels of unconfined aquifers, recharged entirely by rainfall, is done by developing a model for the aquifer that estimates the water-table levels from the history of rainfall observations and past water-table levels. In the present analysis, the model parameters that influence the recharge were not only assumed to be time dependent but also to have varying dependence rates for various parameters. Such a model is solved by the use of a recursive least-squares method. The variable-rate parameter variation is incorporated using a random walk model. From the field tests conducted at Tomago Sandbeds, Newcastle, Australia, it was observed that the assumption of variable rates of time dependency of recharge parameters produced better estimates of water-table levels compared to that with constant-recharge parameters. It was observed that considerable recharge due to rainfall occurred on the very same day of rainfall. The increase in water-table level was insignificant for subsequent days of rainfall. The level of recharge very much depends upon the intensity and history of rainfall. Isolated rainfalls, even of the order of 25 mm day -1, had no significant effect on the water-table levels.

Simulation of proposed increases in ground-water withdrawals on the Atlantic City 800-foot sand, New Jersey coastal plain

USGS Publications Warehouse

Pope, Daryll A.

2006-01-01

The confined Atlantic City 800-foot sand and the unconfined Kirkwood-Cohansey aquifer system (surficial aquifer) are major sources of water for southeastern New Jersey. Because of recent concerns about streamflow depletion resulting from ground-water withdrawals and the potential ecological effects on stream habitat in the area, the focus on future withdrawals has been shifted away from the surficial aquifer to the confined Atlantic City 800-foot sand until the effects of increased withdrawals from the surficial aquifer can be investigated. A study was conducted to evaluate the effects of seven proposed increases in ground-water withdrawals from the Atlantic City 800-foot sand and the Kirkwood-Cohansey aquifer system on the Atlantic City 800-foot sand. The proposed withdrawals are increases above the 2004 allocated rates (full allocation). The effects of full-allocation ground-water withdrawals and the cumulative effect of withdrawals for each of seven proposed increases in withdrawals were simulated using three previously published ground-water flow models: the New Jersey Coastal Plain Regional Aquifer System Analysis model, the Coastal Plain Optimization model, and a model of the Atlantic City 800-foot sand in Atlantic County, New Jersey. These models were used to simulate changes in water levels, the source supplying the increased ground-water flow, and the effects on saltwater movement towards production wells in Cape May County as a result of the proposed increased withdrawals at proposed or existing wells. The results of the simulations represent the effects of the proposed increase from full-allocation withdrawals to an additional 1,825 Mgal/yr (million gallons per year) from the Atlantic City 800-foot sand and an additional 1,045 Mgal/yr from the deep part of the Kirkwood-Cohansey aquifer system near the updip limit of the Atlantic City 800-foot sand. Most of the simulated decline in water levels in Atlantic County occurred as the result of the proposed increased withdrawals simulated for the New Jersey American Water Company wells. Simulated declines in water levels in Cape May were caused mainly by the simulated increased withdrawals for the Cape May City Desalination Plant wells. The additional water to supply the proposed increases in the scenarios was primarily horizontal flow from the unconfined updip part of the Kirkwood-Cohansey aquifer system, which accounted for 63 percent of the inflow, and flow from the overlying Kirkwood-Cohansey aquifer system into the Atlantic City 800-foot sand, which supplied 27 percent of the additional water. Because the withdrawals were made from the confined aquifer and the deeper part of the unconfined aquifer, the effect on streamflow was substantially less than would have occurred had the withdrawals been made directly from the shallower parts of the unconfined aquifer. The travel times from the 250-mg/L isochlor to production wells in Stone Harbor were longer as a result of all the additional withdrawals. For some scenarios, withdrawals in Atlantic County caused the saltwater to move slightly faster towards the production wells. These effects were offset by the increase in travel time caused by the potential increased withdrawals simulated for the Cape May City desalination wells, which either diverted water towards the desalination wells or increased the travel time towards production wells.

Potentiometric Surface of the Aquia Aquifer in Southern Maryland, September 2002

USGS Publications Warehouse

Curtin, Stephen E.; Andreasen, David C.; Wheeler, Judith C.

2003-01-01

This report presents a map showing the potentiometric surface of the Aquia aquifer in the Aquia Formation of Paleocene age in Southern Maryland during September 2002. The map is based on water-level measurements in 94 wells. The highest measured water level was 38 feet above sea level near the northern boundary and outcrop area of the aquifer in the central part of Anne Arundel County, and was below sea level just south of this area and in the remainder of the study area. The hydraulic gradient increased southeastward toward an extensive cone of depression around well fields at Lexington Park and Solomons Island. Another cone of depression occurred in northern Calvert County due to pumpage at and near Chesapeake Beach and North Beach. The water level measured in this area has declined to 55 feet below sea level. The lowest water level measured was 169 feet below sea level at the center of a cone of depression at Lexington Park.

Potentiometric surface of the Aquia Aquifer in southern Maryland, September 2003

USGS Publications Warehouse

Curtin, Stephen E.; Andreason, David C.; Wheeler, Judith C.

2005-01-01

This report presents a map showing the potentiometric surface of the Aquia aquifer in the Aquia Formation of Paleocene age in Southern Maryland during September 2003. The map is based on water-level measurements in 91 wells. The highest measured water level was 40 feet above sea level near the northern boundary and outcrop area of the aquifer in the central part of Anne Arundel County, and was below sea level just south of this area and in the remainder of the study area. The hydraulic gradient increased southeastward toward an extensive cone of depression around well fields at Lexington Park and Solomons Island. Another cone of depression occurred in northern Calvert County due to pumpage at and near North Beach and Chesapeake Beach. The water level measured in this area has declined to 48 feet below sea level. The lowest water level measured was 156 feet below sea level at the center of a cone of depression at Lexington Park.

Energy-Water Nexus: Balancing the Tradeoffs between Two-Level Decision Makers

DOE PAGES

Zhang, Xiaodong; Vesselinov, Velimir Valentinov

2016-09-03

Energy-water nexus has substantially increased importance in the recent years. Synergistic approaches based on systems-analysis and mathematical models are critical for helping decision makers better understand the interrelationships and tradeoffs between energy and water. In energywater nexus management, various decision makers with different goals and preferences, which are often conflicting, are involved. These decision makers may have different controlling power over the management objectives and the decisions. They make decisions sequentially from the upper level to the lower level, challenging decision making in energy-water nexus. In order to address such planning issues, a bi-level decision model is developed, which improvesmore » upon the existing studies by integration of bi-level programming into energy-water nexus management. The developed model represents a methodological contribution to the challenge of sequential decisionmaking in energy-water nexus through provision of an integrated modeling framework/tool. An interactive fuzzy optimization methodology is introduced to seek a satisfactory solution to meet the overall satisfaction of the two-level decision makers. The tradeoffs between the two-level decision makers in energy-water nexus management are effectively addressed and quantified. Application of the proposed model to a synthetic example problem has demonstrated its applicability in practical energy-water nexus management. Optimal solutions for electricity generation, fuel supply, water supply including groundwater, surface water and recycled water, capacity expansion of the power plants, and GHG emission control are generated. In conclusion, these analyses are capable of helping decision makers or stakeholders adjust their tolerances to make informed decisions to achieve the overall satisfaction of energy-water nexus management where bi-level sequential decision making process is involved.« less

Energy-Water Nexus: Balancing the Tradeoffs between Two-Level Decision Makers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Xiaodong; Vesselinov, Velimir Valentinov

Energy-water nexus has substantially increased importance in the recent years. Synergistic approaches based on systems-analysis and mathematical models are critical for helping decision makers better understand the interrelationships and tradeoffs between energy and water. In energywater nexus management, various decision makers with different goals and preferences, which are often conflicting, are involved. These decision makers may have different controlling power over the management objectives and the decisions. They make decisions sequentially from the upper level to the lower level, challenging decision making in energy-water nexus. In order to address such planning issues, a bi-level decision model is developed, which improvesmore » upon the existing studies by integration of bi-level programming into energy-water nexus management. The developed model represents a methodological contribution to the challenge of sequential decisionmaking in energy-water nexus through provision of an integrated modeling framework/tool. An interactive fuzzy optimization methodology is introduced to seek a satisfactory solution to meet the overall satisfaction of the two-level decision makers. The tradeoffs between the two-level decision makers in energy-water nexus management are effectively addressed and quantified. Application of the proposed model to a synthetic example problem has demonstrated its applicability in practical energy-water nexus management. Optimal solutions for electricity generation, fuel supply, water supply including groundwater, surface water and recycled water, capacity expansion of the power plants, and GHG emission control are generated. In conclusion, these analyses are capable of helping decision makers or stakeholders adjust their tolerances to make informed decisions to achieve the overall satisfaction of energy-water nexus management where bi-level sequential decision making process is involved.« less

Predicted water-level and water-quality effects of artificial recharge in the Upper Coachella Valley, California, using a finite-element digital model

USGS Publications Warehouse

Swain, Lindsay A.

1978-01-01

From 1936 to 1974, water levels declined more than 100 feet in the Palm Springs area and 60 feet in the Palm Desert area of the upper Coachella Valley, Calif. Water from the Colorado River Aqueduct is presently being recharged to the basin. The dissolved-solids concentration of native ground water in the recharge area is about 210 mg/liter and that of recharge water ranges from 600 to 750 mg/liter. A finite-element model indicates that without recharge the 1974 water levels in the Palm Springs area will decline 200 feet by the year 2000 because of pumpage. If the aquifer is recharged at a rate from about 7 ,500 acre-feet per year in 1973 increasing to 61,200 acre-feet per year in 1990 and thereafter, the water level in the Palm Springs area will decline about 20 feet below the 1974 level by 1991 and recover to the 1974 level by 2000. The solute-transport finite-element model of the recharge area indicates that the artificial recharge plume (bounded by the 300-mg/liter line) will move about 1.1 miles downgradient of the recharge ponds by 1981 and about 4.5 miles from the ponds by 2000. 

Hydrogeology, hydraulic characteristics, and water-quality conditions in the surficial, Castle Hayne and Peedee aquifers of the greater New Hanover County area, North Carolina, 2012-13

USGS Publications Warehouse

McSwain, Kristen Bukowski; Gurley, Laura N.; Antolino, Dominick J.

2014-01-01

A major issue facing the greater New Hanover County, North Carolina, area is the increased demand for drinking water resources as a result of rapid growth. The principal sources of freshwater supply in the greater New Hanover County area are withdrawals of surface water from the Cape Fear River and groundwater from the underlying Castle Hayne and Peedee aquifers. Industrial, mining, irrigation, and aquaculture groundwater withdrawals increasingly compete with public-supply utilities for freshwater resources. Future population growth and economic expansion will require increased dependence on high-quality sources of fresh groundwater. An evaluation of the hydrogeology and water-quality conditions in the surficial, Castle Hayne, and Peedee aquifers was conducted in New Hanover, eastern Brunswick, and southern Pender Counties, North Carolina. A hydrogeologic framework was delineated by using a description of the geologic and hydrogeologic units that compose aquifers and their confining units. Current and historic water-level, water-quality, and water-isotope data were used to approximate the present boundary between freshwater and brackish water in the study area. Water-level data collected during August–September 2012 and March 2013 in the Castle Hayne aquifer show that recharge areas with the highest groundwater altitudes are located in central New Hanover County, and the lowest are located in a discharge area along the Atlantic Ocean. Between 1964 and 2012, groundwater levels in the Castle Hayne aquifer in central New Hanover County have rebounded by about 10 feet, but in the Pages Creek area groundwater levels declined in excess of 20 feet. In the Peedee aquifer, the August–September 2012 groundwater levels were affected by industrial withdrawals in north-central New Hanover County. Groundwater levels in the Peedee aquifer declined more than 20 feet between 1964 and 2012 in northeastern New Hanover County because of increased withdrawals. Vertical gradients calculated between the Castle Hayne and Peedee aquifers at six well cluster sites were downward in August–September 2012 and March 2013 with the exception of one well pair that had a slight upward gradient in March 2013. Major ion chemistry results from samples collected in August–September 2012 from 97 well sites suggest that seawater is mixing with groundwater in both the Castle Hayne and Peedee aquifers in several locations in Brunswick, New Hanover, and Pender Counties. The 250 milligram per liter line of equal chloride concentration has moved inland in both aquifers since 1965, with the area between Futch and Pages Creeks in northeastern New Hanover County experiencing the greatest increase. Groundwater from the surficial, Castle Hayne, and Peedee aquifers had a stable isotope of water composition similar to that of modern precipitation. A comparison of chloride concentration data collected from public-supply wells in the 1960s with that collected in 2012 shows marked increases in chloride concentrations in the Peedee aquifer near the town of Carolina Beach at the southern end of New Hanover County.

Estimation of Missing Water-Level Data for the Everglades Depth Estimation Network (EDEN)

USGS Publications Warehouse

Conrads, Paul; Petkewich, Matthew D.

2009-01-01

The Everglades Depth Estimation Network (EDEN) is an integrated network of real-time water-level gaging stations, ground-elevation models, and water-surface elevation models designed to provide scientists, engineers, and water-resource managers with current (2000-2009) water-depth information for the entire freshwater portion of the greater Everglades. The U.S. Geological Survey Greater Everglades Priority Ecosystems Science provides support for EDEN and their goal of providing quality-assured monitoring data for the U.S. Army Corps of Engineers Comprehensive Everglades Restoration Plan. To increase the accuracy of the daily water-surface elevation model, water-level estimation equations were developed to fill missing data. To minimize the occurrences of no estimation of data due to missing data for an input station, a minimum of three linear regression equations were developed for each station using different input stations. Of the 726 water-level estimation equations developed to fill missing data at 239 stations, more than 60 percent of the equations have coefficients of determination greater than 0.90, and 92 percent have an coefficient of determination greater than 0.70.

Ground-Water, Surface-Water, and Water-Chemistry Data, Black Mesa Area, Northeastern Arizona-2005-06

USGS Publications Warehouse

Truini, Margot; Macy, J.P.

2007-01-01

The N aquifer is the major source of water in the 5,400 square-mile Black Mesa area in northeastern Arizona. Availability of water is an important issue in northeastern Arizona because of continued water requirements for industrial and municipal use and the needs of a growing population. Precipitation in the Black Mesa area averages about 6 to 14 inches per year. The water monitoring program in the Black Mesa area began in 1971 and is designed to provide information about the long-term effects of ground-water withdrawals from the N aquifer for industrial and municipal uses. This report presents results of data collected for the monitoring program in the Black Mesa area from January 2005 to September 2006. The monitoring program includes measurements of (1) ground-water pumping, (2) ground-water levels, (3) spring discharge, (4) surface-water discharge, (5) ground-water chemistry, and (6) periodic testing of ground-water withdrawal meters. In 2005, ground-water withdrawals in the Black Mesa area totaled 7,330 acre-feet, including ground-water withdrawals for industrial (4,480 acre-feet) and municipal (2,850 acre-feet) uses. From 2004 to 2005, total withdrawals increased by less than 2 percent, industrial withdrawals increased by approximately 3 percent, and total municipal withdrawals increased by 0.35 percent. From 2005 to 2006, annually measured water levels in the Black Mesa area declined in 10 of 13 wells in the unconfined areas of the N aquifer, and the median change was -0.5 foot. Measurements indicated that water levels declined in 12 of 15 wells in the confined area of the aquifer, and the median change was -1.4 feet. From the prestress period (prior to 1965) to 2006, the median water-level change for 29 wells was -8.5 feet. Median water-level changes were -0.2 foot for 13 wells in the unconfined areas and -46.6 feet for 16 wells in the confined area. Ground-water discharges were measured once in 2005 and once in 2006 at Moenkopi School Spring and Burro Spring. Discharge decreased by 3.5 percent at Moenkopi School Spring and by 15 percent at Burro Spring. During the period of record at each spring, discharges fluctuated; a decreasing trend was apparent. Continuous records of surface-water discharge in the Black Mesa area have been collected from streamflow gages at the following sites: Moenkopi Wash (1976 to 2005), Dinnebito Wash (1993 to 2005), Polacca Wash (1994 to 2005), Pasture Canyon Spring (August 2004 to December 2005), and Laguna Creek (1996 to 2005). Median flows during November, December, January, and February of each water year were used as an index of the amount of ground-water discharge to the above named sites. For the period of record at each streamflow-gaging station, the median winter flows have decreased for Moenkopi Wash, Dinnebito Wash, and Polacca Wash. There is not a long enough period of record for Pasture Canyon Spring and Laguna Creek was discontinued at the end of December 2005. In 2006, water samples were collected from 6 wells and 2 springs in the Black Mesa area and analyzed for selected chemical constituents. Dissolved-solids concentrations ranged from 111 to 588 milligrams per liter. Water samples from 5 of the wells and both of the springs had less than 500 milligrams per liter of dissolved solids. Trends in the chemistry of water samples from the 6 wells show the Pi?on NTUA 1 and Peabody 9 wells increasing in dissolved solids, Forest Lake NTUA 1 and Peabody 2 wells decreasing in dissolved solids, and Kykotsmovi PM2 and Keams Canyon PM2 wells show a steady trend. Increasing trends in dissolved-solids, chloride, and sulfate concentrations were evident from the more than 11 years of data for the 2 springs.

Water Quality Assessment for Deep-water Channel area of Guangzhou Port based on the Comprehensive Water Quality Identification Index Method

NASA Astrophysics Data System (ADS)

Chen, Yi

2018-03-01

The comprehensive water quality identification index method is able to assess the general water quality situation comprehensively and represent the water quality classification; water environment functional zone achieves pollution level and standard objectively and systematically. This paper selects 3 representative zones along deep-water channel of Guangzhou port and applies comprehensive water quality identification index method to calculate sea water quality monitoring data for different selected zones from year 2006 to 2014, in order to investigate the temporal variation of water quality along deep-water channel of Guangzhou port. The comprehensive water quality level from north to south presents an increased trend, and the water quality of the three zones in 2014 is much better than in 2006. This paper puts forward environmental protection measurements and suggestions for Pearl River Estuary, provides data support and theoretical basis for studied sea area pollution prevention and control.

Water Quality and Hydrology of Whitefish (Bardon) Lake, Douglas County, Wisconsin, With Special Emphasis on Responses of an Oligotrophic Seepage Lake to Changes in Phosphorus Loading and Water Level

USGS Publications Warehouse

Robertson, Dale M.; Rose, William J.; Juckem, Paul F.

2009-01-01

Whitefish Lake, which is officially named Bardon Lake, is an oligotrophic, soft-water seepage lake in northwestern Wisconsin, and classified by the Wisconsin Department of Natural Resources as an Outstanding Resource Water. Ongoing monitoring of the lake demonstrated that its water quality began to degrade (increased phosphorus and chlorophyll a concentrations) around 2002 following a period of high water level. To provide a better understanding of what caused the degradation in water quality, and provide information to better understand the lake and protect it from future degradation, the U.S. Geological Survey did a detailed study from 2004 to 2008. The goals of the study were to describe the past and present water quality of the lake, quantify water and phosphorus budgets for the lake, simulate the potential effects of changes in phosphorus inputs on the lake's water quality, analyze changes in the water level in the lake since 1900, and relate the importance of changes in climate and changes in anthropogenic (human-induced) factors in the watershed to the water quality of the lake. Since 1998, total phosphorus concentrations increased from near the 0.005-milligrams per liter (mg/L) detection limit to about 0.010 mg/L in 2006, and then decreased slightly in 2007-08. During this time, chlorophyll a concentrations and Secchi depths remained relatively stable at about 1.5 micrograms per liter (ug/L) and 26 feet, respectively. Whitefish Lake is typically classified as oligotrophic. Because the productivity in Whitefish Lake is limited by phosphorus, phosphorus budgets were constructed for the lake. Because it was believed that much of its phosphorus comes from the atmosphere, phosphorus deposition was measured in this study. Phosphorus input from the atmosphere was greater than computed based on previously reported wetfall phosphorus concentrations. The concentrations and deposition rates can be used to estimate atmospheric loading in future lake studies. The average annual load of phosphorus to the lake was 232 pounds: 56 percent from precipitation, 27 percent from groundwater, and 16 percent from septic systems. During a series of dry years (low water levels) and wet years (high water levels), the inputs of water and phosphorus ranged by only 10-13 percent. Results from the Canfield and Bachmann eutrophication model and Carlson trophic-state-index equations demonstrated that the lake directly responds to changes in external phosphorus loading, with percent change in chlorophyll a being similar to the percent change in loading and the change in total phosphorus and Secchi depth being slightly smaller. Therefore, changes in phosphorus loading should affect the water quality of the lake. Specific scenarios that simulated the effects of anthropogenic (human-induced) and climatic (water level) changes demonstrated that: surface-water inflow (runoff) based on current development has little effect on pelagic water quality, changes in the inputs from septic systems and development in the watershed could have a large effect on water quality, and decreases in water and phosphorus loading during periods of low water level had little effect on water quality. Sustained high water levels, resulting from several wet years with relatively high water and phosphorus input, however, could cause a small degradation in water quality. Although high water levels may be associated with a degradation in water quality, it appears that anthropogenic changes in the watershed may be more important in affecting the future water quality of the lake. Fluctuations in water levels since 1998 are representative of what has occurred since 1900, with fluctuations of about 3 feet occurring about every 15 years. Based on total phosphorus concentrations inferred from sediment core analysis, there has been little long-term change in water quality and there has been a slight deterioration in water quality following most periods of high water levels. There

Hydrochemical water evolution in the Aral Sea Basin. Part I: Unconfined groundwater of the Amu Darya Delta - Interactions with surface waters

NASA Astrophysics Data System (ADS)

Schettler, Georg; Oberhänsli, Hedi; Stulina, Galina; Mavlonov, Aslon A.; Naumann, Rudolf

2013-07-01

The Aral Sea, which has been affected by lake level lowering of approximately 25 m and a salinity increase from 10 to >100 g/l since 1963, represents, along with the Amu Dary Delta a dynamic hydrological system under an arid climate regime. The system receives river water inflow at high seasonal and inter-annual variability from remote alpine source areas. In the Amu Darya Delta, there is a distinct salinity contrast between the low-salinity river water (∼1 g/l) and the salinity of the unconfined GW (GWunconf: 10-95 g/l). The GWunconf levels are predominantly controlled by the seepage of the river water inflow and GW discharge into the shrinking Aral Sea. In June 2009 and August 2009, we sampled water from various sources including surface waters, GWunconf, lake water and soil leachates for chemical analyses. Evaporative enrichment, precipitation/dissolution of gypsum and precipitation of calcite drive the GWunconf to an NaCl(SO4) water type presenting a positive correlation between Na and SO4. We model the hydrochemical evolution of the GWunconf in a box model which considers the capillary rise of near-surface GW, the precipitation of minerals in the unsaturated horizon and the seasonal re-flushing of adhesive residual brines and soluble salts. The model documents a rapid increase in salinity over a few annual cycles. Furthermore, the model simulations demonstrate the importance of the aeolian redistribution of soluble salts on the hydrochemical GW evolution. In a lab experiment, halite, hexahydrite and starkeyite are precipitated during the late stages of evaporative enrichment from a representative local brine. Processes specific to different water compartments plausibly explain the variations of selected element ratios. For example, the precipitation of low-Sr calcite in irrigation canals and natural river branches of the delta lowers Ca/Sr. The dissolution of gypsum in soils (Ca/Sr mole ratio ∼ 150) and the possible precipitation of SrSO4 associated with Sr-depletion in adhesive residual brines increases Ca/Sr in seepage and re-increases Ca/Sr in the unconfined GW. Aral Sea water, which receives high-Ca/Sr surface and groundwater inflow, developed due to continued precipitation of high-Ca/Sr calcite the almost lowest Ca/Sr ratio (∼25) over time. We observed spatial variations in the GWunconf composition: (i) ammonium levels increase strongly due to interaction with lake sediments rich in organic matter and (ii) distinct increases in levels of nitrate, U, Mo and Se locally reflect oxygenation when GW levels decrease. The Amu Darya Delta acts as a sink for boron (uptake via terrestrial vegetation) and a source for bromide (release by degradation of organically-bound Br). Our results concerning the hydrochemical evolution of the GWunconf and additional data from the Aral Sea constrain the parameter ‘GW discharge’ in water budget models of the lake and improve the basis for palaeoclimatic interpretations of sediment records from the Aral Sea.

Destruction processes of mining on water environment in the mining area combining isotopic and hydrochemical tracer.

PubMed

Yang, Yonggang; Guo, Tingting; Jiao, Wentao

2018-06-01

There is less research on the hydrological system and its destruction processes mechanism in the mining areas, especially combined application of isotope technology and chemical signals, which is a key scientific problem that need to be solved. This study takes Jinci spring area in Shanxi as a case study. It is based on the data of hydrology and mining condition from 1954 to 2015, combining monitoring experiments, O 18 , D, S 34 and N 15 tracing, chemical and model simulation. This study investigates the hydrological regularity and impacts of mining activities on water quantity and quality, and reveals the destruction process of hydrological system. The results show that: (1) Water chemical type shows an evolutionary trend of HCO 3 - -Ca 2+ -Mg 2+ →SO 4 2- -HCO 3 - -Ca 2+ -Mg 2+ →SO 4 2- -Ca 2+ -Mg 2+ , due to the influence of exploitation and fault zones. Isotope tracer shows that mine pit water is formed by a mixture of pore water, karst water and surface water. (2) Although precipitation and seepage have a certain impact on the reducing of groundwater quantity, over-exploitation of water resource is still the main reason for reducing of groundwater quantity. Under the conditions of keeping the exploitation intensity at the current level or reducing it by 10%, groundwater level shows a declining trend. Under the condition of reducing it by 30%, groundwater level starts to rise up. When reducing by 50%, groundwater level reaches its highest point. Coalmining changes the runoff, recharge and discharge paths. (3) From 1985 to 2015, Water quality in the mining area is worsening. Ca 2+ increases by 35.30%, SO 4 2- increases by 52.80%, and TDS (Total Dissolved Solid) increases by 67.50%. Nitrates come from the industrial and domestic wastewater, which is generated by mining. The percentage of groundwater coming from gypsum dissolusion is 67.51%, and the percentage from coal measure strata water is 34.49%. The water qualities of river branches are generally deteriorated. Copyright © 2018 Elsevier Ltd. All rights reserved.

Cattail invasion of sedge/grass meadows in Lake Ontario: Photointerpretation analysis of sixteen wetlands over five decades

USGS Publications Warehouse

Wilcox, D.A.; Kowalski, K.P.; Hoare, H.L.; Carlson, M.L.; Morgan, H.N.

2008-01-01

Photointerpretation studies were conducted to evaluate vegetation changes in wetlands of Lake Ontario and the upper St. Lawrence River associated with regulation of water levels since about 1960. The studies used photographs from 16 sites (four each from drowned river mouth, barrier beach, open embayment, and protected embayment wetlands) and spanned a period from the 1950s to 2001 at roughly decadal intervals. Meadow marsh was the most prominent vegetation type in most wetlands in the late 1950s when water levels had declined following high lake levels in the early 1950s. Meadow marsh increased at some sites in the mid-1960s in response to low lake levels and decreased at all sites in the late 1970s following a period of high lake levels. Typha increased at nearly all sites, except wave-exposed open embayments, in the 1970s. Meadow marsh continued to decrease and Typha to increase at most sites during sustained higher lake levels through the 1980s, 1990s, and into 2001. Most vegetation changes could be correlated with lake-level changes and with life-history strategies and physiological tolerances to water depth of prominent taxa. Analyses of GIS coverages demonstrated that much of the Typha invasion was landward into meadow marsh, largely by Typha x glauca. Lesser expansion toward open water included both T. x glauca and T. angustifolia. Although many models focus on the seed bank as a key component of vegetative change in wetlands, our results suggest that canopy-dominating, moisture-requiring Typha was able to invade meadow marsh at higher elevations because sustained higher lake levels allowed it to survive and overtake sedges and grasses that can tolerate periods of drier soil conditions.

A novel therapeutic effect of statins on nephrogenic diabetes insipidus

PubMed Central

Bonfrate, Leonilde; Procino, Giuseppe; Wang, David Q-H; Svelto, Maria; Portincasa, Piero

2015-01-01

Statins competitively inhibit hepatic 3-hydroxy-3-methylglutaryl-coenzyme A reductase, resulting in reduced plasma total and low-density lipoprotein cholesterol levels. Recently, it has been shown that statins exert additional ‘pleiotropic’ effects by increasing expression levels of the membrane water channels aquaporin 2 (AQP2). AQP2 is localized mainly in the kidney and plays a critical role in determining cellular water content. This additional effect is independent of cholesterol homoeostasis, and depends on depletion of mevalonate-derived intermediates of sterol synthetic pathways, i.e. farnesylpyrophosphate and geranylgeranylpyrophosphate. By up-regulating the expression levels of AQP2, statins increase water reabsorption by the kidney, thus opening up a new avenue in treating patients with nephrogenic diabetes insipidus (NDI), a hereditary disease that yet lacks high-powered and limited side effects therapy. Aspects related to water balance determined by AQP2 in the kidney, as well as standard and novel therapeutic strategies of NDI are discussed. PMID:25594563

Differences in Field Effectiveness and Adoption between a Novel Automated Chlorination System and Household Manual Chlorination of Drinking Water in Dhaka, Bangladesh: A Randomized Controlled Trial

PubMed Central

Pickering, Amy J.; Crider, Yoshika; Amin, Nuhu; Bauza, Valerie; Unicomb, Leanne; Davis, Jennifer; Luby, Stephen P.

2015-01-01

The number of people served by networked systems that supply intermittent and contaminated drinking water is increasing. In these settings, centralized water treatment is ineffective, while household-level water treatment technologies have not been brought to scale. This study compares a novel low-cost technology designed to passively (automatically) dispense chlorine at shared handpumps with a household-level intervention providing water disinfection tablets (Aquatab), safe water storage containers, and behavior promotion. Twenty compounds were enrolled in Dhaka, Bangladesh, and randomly assigned to one of three groups: passive chlorinator, Aquatabs, or control. Over a 10-month intervention period, the mean percentage of households whose stored drinking water had detectable total chlorine was 75% in compounds with access to the passive chlorinator, 72% in compounds receiving Aquatabs, and 6% in control compounds. Both interventions also significantly improved microbial water quality. Aquatabs usage fell by 50% after behavioral promotion visits concluded, suggesting intensive promotion is necessary for sustained uptake. The study findings suggest high potential for an automated decentralized water treatment system to increase consistent access to clean water in low-income urban communities. PMID:25734448