Getting the lead out: understanding risks in the distribution ...

EPA Pesticide Factsheets

This presentation discusses the importance of the water distribution system as a component of the source-to-tap continuum in public health protection. Issues covered include: understanding source water quality changes and their impacts throughout the system; use of mitigation measures such as filters); and holistic approaches and/or strategies that could be used to avoid unintended consequences of decisions from source to tap. Invited presentation on topics indicated as of interest. With exposure to lead as the context, this presentation discusses the importance of the water distribution system as a component of the source-to-tap continuum in public health protection. Issues covered include: understanding source water quality changes and their impacts throughout the system; use of mitigation measures such as filters); and holistic approaches and/or strategies that could be used to avoid unintended consequences of decisions from source to tap.

Water pollution in Pakistan and its impact on public health--a review.

PubMed

Azizullah, Azizullah; Khattak, Muhammad Nasir Khan; Richter, Peter; Häder, Donat-Peter

2011-02-01

Water pollution is one of the major threats to public health in Pakistan. Drinking water quality is poorly managed and monitored. Pakistan ranks at number 80 among 122 nations regarding drinking water quality. Drinking water sources, both surface and groundwater are contaminated with coliforms, toxic metals and pesticides throughout the country. Various drinking water quality parameters set by WHO are frequently violated. Human activities like improper disposal of municipal and industrial effluents and indiscriminate applications of agrochemicals in agriculture are the main factors contributing to the deterioration of water quality. Microbial and chemical pollutants are the main factors responsible exclusively or in combination for various public health problems. This review discusses a detailed layout of drinking water quality in Pakistan with special emphasis on major pollutants, sources of pollution and the consequent health problems. The data presented in this review are extracted from various studies published in national and international journals. Also reports released by the government and non-governmental organizations are included. Copyright © 2010 Elsevier Ltd. All rights reserved.

Can we treat enough water to meet water quality goals

USDA-ARS?s Scientific Manuscript database

Denitrifying woodchip bioreactors are sized to treat a portion of subsurface drainage flow from a given system. Over sizing them can create conditions under which unintended consequences could occur. A potential solution for treating additional water is to use a cascading series of bioreactor cell...

The Impacts of Spatiotemporal Landscape Changes on Water Quality in Shenzhen, China

PubMed Central

Liu, Zhenhuan; Yang, Haiyan

2018-01-01

The urban landscape in China has changed rapidly over the past four decades, which has led to various environmental consequences, such as water quality degradation at the regional scale. To improve water restoration strategies and policies, this study assessed the relationship between water quality and landscape change in Shenzhen, China, using panel regression analysis. The results show that decreases in natural and semi-natural landscape compositions have had significant negative effects on water quality. Landscape composition and configuration changes accounted for 39–58% of the variation in regional water quality degradation. Additionally, landscape fragmentation indices, such as patch density (PD) and the number of patches (NP), are important indicators of the drivers of water quality degradation. PD accounted for 2.03–5.44% of the variability in water quality, while NP accounted for −1.63% to −4.98% of the variability. These results indicate that reducing landscape fragmentation and enhancing natural landscape composition at the watershed scale are vital to improving regional water quality. The study findings suggest that urban landscape optimization is a promising strategy for mitigating urban water quality degradation, and the results can be used in policy making for the sustainable development of the hydrological environment in rapidly urbanizing areas. PMID:29786672

The Impacts of Spatiotemporal Landscape Changes on Water Quality in Shenzhen, China.

PubMed

Liu, Zhenhuan; Yang, Haiyan

2018-05-22

The urban landscape in China has changed rapidly over the past four decades, which has led to various environmental consequences, such as water quality degradation at the regional scale. To improve water restoration strategies and policies, this study assessed the relationship between water quality and landscape change in Shenzhen, China, using panel regression analysis. The results show that decreases in natural and semi-natural landscape compositions have had significant negative effects on water quality. Landscape composition and configuration changes accounted for 39⁻58% of the variation in regional water quality degradation. Additionally, landscape fragmentation indices, such as patch density (PD) and the number of patches (NP), are important indicators of the drivers of water quality degradation. PD accounted for 2.03⁻5.44% of the variability in water quality, while NP accounted for -1.63% to -4.98% of the variability. These results indicate that reducing landscape fragmentation and enhancing natural landscape composition at the watershed scale are vital to improving regional water quality. The study findings suggest that urban landscape optimization is a promising strategy for mitigating urban water quality degradation, and the results can be used in policy making for the sustainable development of the hydrological environment in rapidly urbanizing areas.

Application of CCME Water Quality Index to monitor water quality: a case study of the Mackenzie River Basin, Canada.

PubMed

Lumb, Ashok; Halliwell, Doug; Sharma, Tribeni

2006-02-01

All six ecosystem initiatives evolved from many years of federal, provincial, First Nation, local government and community attention to the stresses on sensitive habitats and species, air and water quality, and the consequent threats to community livability. This paper assesses water quality aspect for the ecosystem initiatives and employs newly developed Canadian Council of Ministers of the Environment Water Quality Index (CCME WQI) which provides a convenient mean of summarizing complex water quality data that can be easily understood by the public, water distributors, planners, managers and policy makers. The CCME WQI incorporates three elements: Scope - the number of water quality parameters (variables) not meeting water quality objectives (F(1)); Frequency - the number of times the objectives are not met (F(2)); and Amplitude. the extent to which the objectives are not met (F(3)). The index produces a number between 0 (worst) to 100 (best) to reflect the water quality. This study evaluates water quality of the Mackenzie - Great Bear sub-basin by employing two modes of objective functions (threshold values): one based on the CCME water quality guidelines and the other based on site-specific values that were determined by the statistical analysis of the historical data base. Results suggest that the water quality of the Mackenzie-Great Bear sub-basin is impacted by high turbidity and total (mostly particulate) trace metals due to high suspended sediment loads during the open water season. Comments are also provided on water quality and human health issues in the Mackenzie basin based on the findings and the usefulness of CCME water quality guidelines and site specific values.

Modeling and Optimization for Management of Intermittent Water Supply

NASA Astrophysics Data System (ADS)

Lieb, A. M.; Wilkening, J.; Rycroft, C.

2014-12-01

In many urban areas, piped water is supplied only intermittently, as valves direct water to different parts of the water distribution system at different times. The flow is transient, and may transition between free-surface and pressurized, resulting in complex dynamical features with important consequences for water suppliers and users. These consequences include degradation of distribution system components, compromised water quality, and inequitable water availability. The goal of this work is to model the important dynamics and identify operating conditions that mitigate certain negative effects of intermittent water supply. Specifically, we will look at controlling valve parameters occurring as boundary conditions in a network model of transient, transition flow through closed pipes. Gradient-based optimization will be used to find boundary values to minimize pressure gradients and ensure equitable water availability at system endpoints.

Optimal Dynamics of Intermittent Water Supply

NASA Astrophysics Data System (ADS)

Lieb, Anna; Wilkening, Jon; Rycroft, Chris

2014-11-01

In many urban areas of the developing world, piped water is supplied only intermittently, as valves direct water to different parts of the water distribution system at different times. The flow is transient, and may transition between free-surface and pressurized, resulting in complex dynamical features with important consequences for water suppliers and users. These consequences include degradation of distribution system components, compromised water quality, and inequitable water availability. The goal of this work is to model the important dynamics and identify operating conditions that mitigate certain negative effects of intermittent water supply. Specifically, we will look at valve parameters occurring as boundary conditions in a network model of transient, transition flow through closed pipes. Optimization will be used to find boundary values to minimize pressure gradients and ensure equitable water availability.

Water quality key to protecting patients.

PubMed

Pearson, Susan

2012-11-01

According to David Graham of the Scottish National Blood Transfusion Service (SNBTS), "the importance of the safe diagnosis and treatment of patients cannot be overstated - yet the role played by water quality in patient safety has sometimes been under-stated". David Graham was speaking at a one day Pall Medical-sponsored meeting on the prevention and control of healthcare-associated waterborne infections in healthcare facilities held in Edinburgh earlier this year. David Graham, other speakers, and the chair, Consultant Microbiologist and Infection Prevention and Control Doctor for NHS Grampian, Dr Anne Marie Karcher, stressed that good quality water is essential in healthcare premises to prevent the potentially catastrophic consequences of contaminated water for some patients. Susan Pearson BSc reports.

Enhancing water quality in hydropower system operations

NASA Astrophysics Data System (ADS)

Hayes, Donald F.; Labadie, John W.; Sanders, Thomas G.; Brown, Jackson K.

1998-03-01

The quality of impounded waters often degrades over time because of thermal stratification, sediment oxygen demands, and accumulation of pollutants. Consequently, reservoir releases impact water quality in tailwaters, channels, and other downstream water bodies. Low dissolved oxygen (DO) concentrations in the Cumberland River below Old Hickory dam result from stratification of upstream reservoirs and seasonally low release rates. Operational changes in upstream hydropower reservoirs may be one method to increase DO levels without substantially impacting existing project purposes. A water quality model of the upper Cumberland basin is integrated into an optimal control algorithm to evaluate water quality improvement opportunities through operational modifications. The integrated water quantity/quality model maximizes hydropower revenues, subject to various flow and headwater operational restrictions for satisfying multiple project purposes, as well as maintenance of water quality targets. Optimal daily reservoir release policies are determined for the summer drawdown period which increase DO concentrations under stratification conditions with minimal impact on hydropower production and other project purposes. Appendixes A-D available with entire article on microfiche. Order by mail from AGU, 2000 Florida Ave., N.W., Washington, DC 20009 or by phone at 800-966-2481; $2.50. Document W97-003. Payment must accompany order.

Quality-assurance data, comparison to water-quality standards, and site considerations for total dissolved gas and water temperature, lower Columbia River, Oregon and Washington, 2001

USGS Publications Warehouse

Tanner, Dwight Q.; Bragg, Heather M.

2002-03-06

At times in July and August 2001, the total-dissolved-gas probe at Warrendale could not be positioned below the minimum compensation depth because the river was too shallow at that location. Consequently, degassing at probe depth may have occurred, and total dissolved gas may have been larger in locations with greater depths.

ATRAZINE ECOLOGICAL EFFECTS ASSESSMENT FOR OPP LEVEL OF CONCERN AND OW WATER QUALITY CRITERION FOR AQUATIC LIFE

EPA Science Inventory

Atrazine is a relatively water-soluble and persistent herbicide that can reach concentrations of possible ecological concern for aquatic plants in vulnerable watersheds in regions with high agricultural usage of atrazine. As a consequence, the U.S. EPA Office of Water is current...

The hydrological consequences of human impact in the Lublin Region

NASA Astrophysics Data System (ADS)

Michalczyk, Zdzisław; Mięsiak-Wójcik, Katarzyna; Sposób, Joanna; Turczyński, Marek

2012-01-01

The Lublin Region is an area where local transformations in the natural environment, including the hydrosphere, occur. They result from the impact of agriculture, industry as well as water supply and sewage disposal. These activities lead to changes in the water network resulting from land improvement works, channel straightening and water runoff acceleration, as well as to the formation of local, both point and diffuse sources, of water pollution. The consequences of human impact are manifested in local transformations of the quality or quantity of water resources. As a result of intense groundwater draw-off, hydrogeological conditions are transformed, which is reflected in the persistence of depression cones of varied size and depth, noticeable in the vicinity of water intakes for Lublin, Chełm, Zamość and Kraśnik. The lowering of the first-level groundwater table also occurs as a consequence of the drainage of chalk and marl mine workings in Chełm and Rejowiec, whereas in the area of the hard coal mine both shallow and deep groundwater was transformed. It is important to indicate the consequences of human impact changes of water conditions as the hydrosphere resources should be used according to the principles of sustainable development.

Linking water quality and well-being for improved assessment and valuation of ecosystem services

PubMed Central

Keeler, Bonnie L.; Polasky, Stephen; Brauman, Kate A.; Johnson, Kris A.; Finlay, Jacques C.; O’Neill, Ann; Kovacs, Kent; Dalzell, Brent

2012-01-01

Despite broad recognition of the value of the goods and services provided by nature, existing tools for assessing and valuing ecosystem services often fall short of the needs and expectations of decision makers. Here we address one of the most important missing components in the current ecosystem services toolbox: a comprehensive and generalizable framework for describing and valuing water quality-related services. Water quality is often misrepresented as a final ecosystem service. We argue that it is actually an important contributor to many different services, from recreation to human health. We present a valuation approach for water quality-related services that is sensitive to different actions that affect water quality, identifies aquatic endpoints where the consequences of changing water quality on human well-being are realized, and recognizes the unique groups of beneficiaries affected by those changes. We describe the multiple biophysical and economic pathways that link actions to changes in water quality-related ecosystem goods and services and provide guidance to researchers interested in valuing these changes. Finally, we present a valuation template that integrates biophysical and economic models, links actions to changes in service provision and value estimates, and considers multiple sources of water quality-related ecosystem service values without double counting. PMID:23091018

Linking water quality and well-being for improved assessment and valuation of ecosystem services.

PubMed

Keeler, Bonnie L; Polasky, Stephen; Brauman, Kate A; Johnson, Kris A; Finlay, Jacques C; O'Neill, Ann; Kovacs, Kent; Dalzell, Brent

2012-11-06

Despite broad recognition of the value of the goods and services provided by nature, existing tools for assessing and valuing ecosystem services often fall short of the needs and expectations of decision makers. Here we address one of the most important missing components in the current ecosystem services toolbox: a comprehensive and generalizable framework for describing and valuing water quality-related services. Water quality is often misrepresented as a final ecosystem service. We argue that it is actually an important contributor to many different services, from recreation to human health. We present a valuation approach for water quality-related services that is sensitive to different actions that affect water quality, identifies aquatic endpoints where the consequences of changing water quality on human well-being are realized, and recognizes the unique groups of beneficiaries affected by those changes. We describe the multiple biophysical and economic pathways that link actions to changes in water quality-related ecosystem goods and services and provide guidance to researchers interested in valuing these changes. Finally, we present a valuation template that integrates biophysical and economic models, links actions to changes in service provision and value estimates, and considers multiple sources of water quality-related ecosystem service values without double counting.

Desert amphibian selection of arid land breeding habitat undermines reproductive effort.

PubMed

Kiesow, Anja B; Griffis-Kyle, Kerry L

2017-12-01

Understanding how animals select habitat is important for understanding how to better conserve those species. As droughts become more frequent and water availability declines in many systems, understanding selection of water sources becomes even more important for conservation. Tinajas and anthropogenic catchments are critical ephemeral breeding sites for Sonoran Desert anurans. Tadpoles have been documented in both water types even though anthropogenic catchments can contain very high concentrations of ammonia. We currently do not know how amphibians are selecting breeding habitat. We tested three hypotheses of habitat selection based on resource quality, resource quality and territoriality, and proximity of water site to other water sites. Male Anaxyrus punctatus called from all sites regardless of habitat quality or male quality; however, they were found more often at sites within 2 km of other sites. This suggests that male desert anurans are selecting close breeding habitat regardless of quality for breeding, indicating ammoniated sites are likely either population sinks or ecological traps. Consequently, adding anthropogenic water sites, without managing to reduce ammonia, will provide low quality habitat that could cause long-term declines in desert anuran populations.

Anticipated water quality changes in response to climate change and potential consequences for inland fishes

USGS Publications Warehouse

Chen, Yushun; Todd, Andrew S.; Murphy, Margaret H.; Lomnicky, Gregg

2016-01-01

Healthy freshwater ecosystems are a critical component of the world's economy, with a critical role in maintaining public health, inland biological diversity, and overall quality of life. Globally, our climate is changing, with air temperature and precipitation regimes deviating significantly from historical patterns. Healthy freshwater ecosystems are a critical component of the world's economy, with a critical role in maintaining public health, inland biological diversity, and overall quality of life. Globally, our climate is changing, with air temperature and precipitation regimes deviating significantly from historical patterns. Changes anticipated with climate change in the future are likely to have a profound effect on inland aquatic ecosystems through diverse pathways, including changes in water quality. In this brief article, we present an initial discussion of several of the water quality responses that can be anticipated to occur within inland water bodies with climate change and how those changes are likely to impact fishes.

Simulating ensembles of source water quality using a K-nearest neighbor resampling approach.

PubMed

Towler, Erin; Rajagopalan, Balaji; Seidel, Chad; Summers, R Scott

2009-03-01

Climatological, geological, and water management factors can cause significant variability in surface water quality. As drinking water quality standards become more stringent, the ability to quantify the variability of source water quality becomes more important for decision-making and planning in water treatment for regulatory compliance. However, paucity of long-term water quality data makes it challenging to apply traditional simulation techniques. To overcome this limitation, we have developed and applied a robust nonparametric K-nearest neighbor (K-nn) bootstrap approach utilizing the United States Environmental Protection Agency's Information Collection Rule (ICR) data. In this technique, first an appropriate "feature vector" is formed from the best available explanatory variables. The nearest neighbors to the feature vector are identified from the ICR data and are resampled using a weight function. Repetition of this results in water quality ensembles, and consequently the distribution and the quantification of the variability. The main strengths of the approach are its flexibility, simplicity, and the ability to use a large amount of spatial data with limited temporal extent to provide water quality ensembles for any given location. We demonstrate this approach by applying it to simulate monthly ensembles of total organic carbon for two utilities in the U.S. with very different watersheds and to alkalinity and bromide at two other U.S. utilities.

The Road to TMDL is Paved with Good Intentions--Total Maximum Daily Loads for a Wild and Scenic River in the Southern Appalachians

Treesearch

M.S. Riedel; J.M. Vose; D.S. Leigh

2003-01-01

We monitored water quality in the Chattooga River Watershed (NE Georgia, NW South Carolina, and SW North Carolina) to compare sediment TMDLs with observed water quality. A judicial consent decree required the EPA to establish TMDLs in one year. The EPA was unable to fully characterize the sediment budgets of these streams and consequently issued phased sediment TMDLs...

INVESTIGATING THE SOURCES OF THE MUTAGENIC ACTIVITY FOUND IN A RIVER USING THE SALMONELLA ASSAY AND DIFFERENT WATER EXTRACTION PROCEDURES

EPA Science Inventory

Abstract
As a consequence of the routine surface water quality-monitoring program of Sao Paulo State (Brazil), which includes the Salmonella microsome mutagenicity assay as one of its parameters, we detected a river used as a drinking water source after treatment, that repeate...

Controlling flooding and water pollution with upland and streamside vegetation systems

Treesearch

Michael Dosskey

2003-01-01

Substantial research and development effort in the U.S. is being spent on developing strategies that address flooding and water pollution problems in agricultural areas. Concerns have been raised about the costs of flood damage, degradation of productive farm land, and declining water quality that are now recognized as unintended consequences of intensive, high-yield...

Continuous exposure to dibromoacetic acid delays pubertal development and compromises sperm quality in the rat

EPA Science Inventory

Previously our work on the haloacid by-products of drinking water disinfection focused on adult exposures. Herein we evaluate the consequence of continuous exposure to dibromoacetic acid (DBA) via drinking water through reproductive development into adulthood. An initial study in...

Drinking water sources, availability, quality, access and utilization for goats in the Karak Governorate, Jordan.

PubMed

Al-Khaza'leh, Ja'far Mansur; Reiber, Christoph; Al Baqain, Raid; Valle Zárate, Anne

2015-01-01

Goat production is an important agricultural activity in Jordan. The country is one of the poorest countries in the world in terms of water scarcity. Provision of sufficient quantity of good quality drinking water is important for goats to maintain feed intake and production. This study aimed to evaluate the seasonal availability and quality of goats' drinking water sources, accessibility, and utilization in different zones in the Karak Governorate in southern Jordan. Data collection methods comprised interviews with purposively selected farmers and quality assessment of water sources. The provision of drinking water was considered as one of the major constraints for goat production, particularly during the dry season (DS). Long travel distances to the water sources, waiting time at watering points, and high fuel and labor costs were the key reasons associated with the problem. All the values of water quality (WQ) parameters were within acceptable limits of the guidelines for livestock drinking WQ with exception of iron, which showed slightly elevated concentration in one borehole source in the DS. These findings show that water shortage is an important problem leading to consequences for goat keepers. To alleviate the water shortage constraint and in view of the depleted groundwater sources, alternative water sources at reasonable distance have to be tapped and monitored for water quality and more efficient use of rainwater harvesting systems in the study area is recommended.

Documenting Environmental Degradation and Its Consequences Using Visual Methods as Pedagogical Tools in Social Work Education

ERIC Educational Resources Information Center

Moxley, David P.

2018-01-01

Environmental degradation, including the depletion of natural resources, the distortion of environmental aesthetics, diminished physical infrastructure, and the poisoning of essential environmental supplies involving air, water, and soil abridge environmental quality, particularly for those who are impoverished, possess qualities that do not fit…

Water resources between conditions of quality and quantity in the Oued Souf region!

NASA Astrophysics Data System (ADS)

Miloudi, Abdelmonem; Remini, Bouallem

2018-05-01

Waters from the Terminal complex (TC) in the Souf region have been gushing since Spring1956 through the first drilling carried out in the municipality of Guemmar (El-Oued) to ensure the need for drinking water requirements. Water needs of the habitat and farmers are increasing with the population growth in the Souf region; there are 153 boreholes in the Terminal complex for Habitat needs, of which more than 80% are available for drinking water supply. These needs are causing negative consequences for the serene life of the Souafa by the phenomenon of water upwellings, the free water table, and the change in the quality of the waters from the Terminal complex. Our work will be conducted to produce a piezometric map of the Souf Terminal complex and to conduct a study on the quality of water resources in the Algerian south-east, leading to a diagnosis of pollution and its impact on the water. The quality of water resources is examined by the establishment of sampling and water analysis campaigns for both irrigation and public consumption, following the static measurement of water levels in the network boreholes of TC Monitoring.

Regional Monitoring of Coral Condition in the Florida Keys

Treesearch

William S. Fisher; Deborah L. Santavy; William P. Davis; Lee A. Courtney

2006-01-01

Tropical reef corals have experienced unprecedented levels of bleaching and disease during the last three decades. Declining health has been attributed to several stressors, including exposures to elevated water temperature, increased solar radiation, and degraded water quality. Consequences of coral bleaching and disease vary; some recover, while others lose tissue,...

Are harmful algal blooms becoming the greatest inland water quality threat to public health and aquatic ecosystems?

PubMed

Brooks, Bryan W; Lazorchak, James M; Howard, Meredith D A; Johnson, Mari-Vaughn V; Morton, Steve L; Perkins, Dawn A K; Reavie, Euan D; Scott, Geoffrey I; Smith, Stephanie A; Steevens, Jeffery A

2016-01-01

In this Focus article, the authors ask a seemingly simple question: Are harmful algal blooms (HABs) becoming the greatest inland water quality threat to public health and aquatic ecosystems? When HAB events require restrictions on fisheries, recreation, and drinking water uses of inland water bodies significant economic consequences result. Unfortunately, the magnitude, frequency, and duration of HABs in inland waters are poorly understood across spatiotemporal scales and differentially engaged among states, tribes, and territories. Harmful algal bloom impacts are not as predictable as those from conventional chemical contaminants, for which water quality assessment and management programs were primarily developed, because interactions among multiple natural and anthropogenic factors determine the likelihood and severity to which a HAB will occur in a specific water body. These forcing factors can also affect toxin production. Beyond site-specific water quality degradation caused directly by HABs, the presence of HAB toxins can negatively influence routine surface water quality monitoring, assessment, and management practices. Harmful algal blooms present significant challenges for achieving water quality protection and restoration goals when these toxins confound interpretation of monitoring results and environmental quality standards implementation efforts for other chemicals and stressors. Whether HABs presently represent the greatest threat to inland water quality is debatable, though in inland waters of developed countries they typically cause more severe acute impacts to environmental quality than conventional chemical contamination events. The authors identify several timely research needs. Environmental toxicology, environmental chemistry, and risk-assessment expertise must interface with ecologists, engineers, and public health practitioners to engage the complexities of HAB assessment and management, to address the forcing factors for HAB formation, and to reduce the threats posed to inland surface water quality. © 2015 SETAC.

Influence of land use on water quality in a tropical landscape: a multi-scale analysis

PubMed Central

Yackulic, Charles B.; Lim, Yili; Arce-Nazario, Javier A.

2015-01-01

There is a pressing need to understand the consequences of human activities, such as land transformations, on watershed ecosystem services. This is a challenging task because different indicators of water quality and yield are expected to vary in their responsiveness to large versus local-scale heterogeneity in land use and land cover (LUC). Here we rely on water quality data collected between 1977 and 2000 from dozens of gauge stations in Puerto Rico together with precipitation data and land cover maps to (1) quantify impacts of spatial heterogeneity in LUC on several water quality indicators; (2) determine the spatial scale at which this heterogeneity influences water quality; and (3) examine how antecedent precipitation modulates these impacts. Our models explained 30–58% of observed variance in water quality metrics. Temporal variation in antecedent precipitation and changes in LUC between measurements periods rather than spatial variation in LUC accounted for the majority of variation in water quality. Urbanization and pasture development generally degraded water quality while agriculture and secondary forest re-growth had mixed impacts. The spatial scale over which LUC influenced water quality differed across indicators. Turbidity and dissolved oxygen (DO) responded to LUC in large-scale watersheds, in-stream nitrogen concentrations to LUC in riparian buffers of large watersheds, and fecal matter content and in-stream phosphorus concentration to LUC at the sub-watershed scale. Stream discharge modulated impacts of LUC on water quality for most of the metrics. Our findings highlight the importance of considering multiple spatial scales for understanding the impacts of human activities on watershed ecosystem services. PMID:26146455

Effect of degrading yellow oxo-biodegradable low-density polyethylene films to water quality

NASA Astrophysics Data System (ADS)

Requejo, B. A.; Pajarito, B. B.

2017-05-01

Polyethylene (PE) contributes largely to plastic wastes that are disposed in aquatic environment as a consequence of its widespread use. In this study, yellow oxo-biodegradable low-density PE films were immersed in deionized water at 50°C for 49 days. Indicators of water quality: pH, oxidation-reduction potential, turbidity, and total dissolved solids (TDS), were monitored at regular intervals. It was observed that pH initially rises and then slowly decreases with time, oxidation-reduction potential decreases then slowly increases with time, turbidity rises above the control at varied rates, and TDS increases abruptly and rises at a hindered rate. Moreover, the films potentially leach out lead chromate. The results imply that degrading oxo-biodegradable LDPE films results to significant reduction of water quality.

Water resources management strategies and its implications on hydrodynamic and hydrochemical changes of costal groundwater: Case of Grombalia shallow aquifer, NE Tunisia

NASA Astrophysics Data System (ADS)

Lachaal, Fethi; Chekirbane, Anis; Chargui, Sameh; Sellami, Haykel; Tsujimura, Maki; Hezzi, Hmida; Faycel, Jelassi; Mlayah, Ammar

2016-12-01

Information on groundwater quantity as well as quality is required by water managers and decision-makers for defining a sustainable management strategy. This requires a comprehensive assessment of the surface water and groundwater resources. This paper provides an assessment of water resources management strategy in the Grombalia region (Northeast Tunisia) and its impact on quantity and quality evolution of groundwater resources based on an approach that combines (i) hydro-climatic data, (ii) field monitoring, (iii) historic piezometric records, and (iv) geochemical and stable isotopes (δ18O and δ2H) analyses. We apply this approach to identify the origin of the various water resources and outline how the actual water management impact the quantity and quality of the groundwater in the region. As consequence of poor water resources management, the shallow groundwater levels have been disrupted: a groundwater rise is observed in the centre and a piezometric drawdown is observed in the upstream regions. Groundwater quality degradation was registered especially in the centre and downstream zones.

Flood frequency matters: Why climate change degrades deep-water quality of peri-alpine lakes

NASA Astrophysics Data System (ADS)

Fink, Gabriel; Wessels, Martin; Wüest, Alfred

2016-09-01

Sediment-laden riverine floods transport large quantities of dissolved oxygen into the receiving deep layers of lakes. Hence, the water quality of deep lakes is strongly influenced by the frequency of riverine floods. Although flood frequency reflects climate conditions, the effects of climate variability on the water quality of deep lakes is largely unknown. We quantified the effects of climate variability on the potential shifts in the flood regime of the Alpine Rhine, the main catchment of Lake Constance, and determined the intrusion depths of riverine density-driven underflows and the subsequent effects on water exchange rates in the lake. A simplified hydrodynamic underflow model was developed and validated with observed river inflow and underflow events. The model was implemented to estimate underflow statistics for different river inflow scenarios. Using this approach, we integrated present and possible future flood frequencies to underflow occurrences and intrusion depths in Lake Constance. The results indicate that more floods will increase the number of underflows and the intensity of deep-water renewal - and consequently will cause higher deep-water dissolved oxygen concentrations. Vice versa, fewer floods weaken deep-water renewal and lead to lower deep-water dissolved oxygen concentrations. Meanwhile, a change from glacial nival regime (present) to a nival pluvial regime (future) is expected to decrease deep-water renewal. While flood frequencies are not expected to change noticeably for the next decades, it is most likely that increased winter discharge and decreased summer discharge will reduce the number of deep density-driven underflows by 10% and favour shallower riverine interflows in the upper hypolimnion. The renewal in the deepest layers is expected to be reduced by nearly 27%. This study underlines potential consequences of climate change on the occurrence of deep river underflows and water residence times in deep lakes.

Classroom Activities about Water and Climate Change

NASA Astrophysics Data System (ADS)

Rodriguez, M.

2012-04-01

The purpose of this activity is to demonstrate practical work and experiments in the classroom, with students on Water: Water is the most neccesary Earth's resource, although it is decreasing because many human activities are changing its quality and its availability. The activity is designed in order to recreate experiments, simulations, and determine the aspects of the problematic environment currently plaguing our planet, especially those related to water and climate change. The selected activities have to be easy to make, and easy to understand. Each activity will be illustrated, explained and described using pictures and short texts, so teachers could replay them in their classroom. 1. Simulation of the Ocean Water Currents Convection to understand the heat distribution in our planet. 2. Ocean Water Stratification According to Water Salinity. We can understand the behaviour of water when we mix water from different densities 3. Melting of the Arctic and Antarctic Polar Caps. In this experiment, we can see the consequences of changing environment and climate conditions as it pertains to ice and our polar ice caps. We want to show the different behaviours of continental and floating ice and to evaluate the consequences of their melting. 4. Detecting water pollution. Here, we can analyse some water patterns and get to know the existence or absence of pollutants in the water, as well as learning how to determine its pH level, hardness, nitrogen composition, bacteria content and more. 5. Creating a home treatment. We show the necessity to preserve the water quality through a suitable treatment.

Storm water management in an urban catchment: effects of source control and real-time management of sewer systems on receiving water quality.

PubMed

Frehmann, T; Nafo, I; Niemann, A; Geiger, W F

2002-01-01

For the examination of the effects of different storm water management strategies in an urban catchment area on receiving water quality, an integrated simulation of the sewer system, wastewater treatment plant and receiving water is carried out. In the sewer system real-time control measures are implemented. As examples of source control measures the reduction of wastewater and the reduction of the amount of impervious surfaces producing storm water discharges are examined. The surface runoff calculation and the simulation of the sewer system and the WWTP are based on a MATLAB/SIMULINK simulation environment. The impact of the measures on the receiving water is simulated using AQUASIM. It can be shown that the examined storm water management measures, especially the source control measures, can reduce the combined sewer overflow volume and the pollutant discharge load considerably. All examined measures also have positive effects on the receiving water quality. Moreover, the reduction of impervious surfaces avoids combined sewer overflow activities, and in consequence prevents pollutants from discharging into the receiving water after small rainfall events. However, the receiving water quality improvement may not be seen as important enough to avoid acute receiving water effects in general.

Water quality of Danube Delta systems: ecological status and prediction using machine-learning algorithms.

PubMed

Stoica, C; Camejo, J; Banciu, A; Nita-Lazar, M; Paun, I; Cristofor, S; Pacheco, O R; Guevara, M

2016-01-01

Environmental issues have a worldwide impact on water bodies, including the Danube Delta, the largest European wetland. The Water Framework Directive (2000/60/EC) implementation operates toward solving environmental issues from European and national level. As a consequence, the water quality and the biocenosis structure was altered, especially the composition of the macro invertebrate community which is closely related to habitat and substrate heterogeneity. This study aims to assess the ecological status of Southern Branch of the Danube Delta, Saint Gheorghe, using benthic fauna and a computational method as an alternative for monitoring the water quality in real time. The analysis of spatial and temporal variability of unicriterial and multicriterial indices were used to assess the current status of aquatic systems. In addition, chemical status was characterized. Coliform bacteria and several chemical parameters were used to feed machine-learning (ML) algorithms to simulate a real-time classification method. Overall, the assessment of the water bodies indicated a moderate ecological status based on the biological quality elements or a good ecological status based on chemical and ML algorithms criteria.

Assessment of tap water quality and corrosion scales from the selected distribution systems in northern Pakistan.

PubMed

Baig, Shams Ali; Lou, Zimo; Baig, Muzaffar Ali; Qasim, Muhammad; Shams, Dilawar Farhan; Mahmood, Qaisar; Xu, Xinhua

2017-04-01

Corrosion deposits formed within drinking water distribution systems deteriorate drinking water quality and resultantly cause public health consequences. In the present study, an attempt was made to investigate the concurrent conditions of corrosion scales and the drinking water quality in selected water supply schemes (WSS) in districts Chitral, Peshawar, and Abbottabad, northern Pakistan. Characterization analyses of the corrosion by-products revealed the presence of α-FeOOH, γ-FeOOH, Fe 3 O 4 , and SiO 2 as major constituents with different proportions. The constituents of all the representative XRD peaks of Peshawar WSS were found insignificant as compared to other WSS, and the reason could be the variation of source water quality. Well-crystallized particles in SEM images indicated the formation of dense oxide layer on corrosion by-products. A wider asymmetric vibration peak of SiO 2 appeared only in Chitral and Abbottabad WSS, which demonstrated higher siltation in the water source. One-way ANOVA analysis showed significant variations in pH, turbidity, TDS, K, Mg, PO 4 , Cl, and SO 4 values, which revealed that these parameters differently contributed to the source water quality. Findings from this study suggested the implementation of proper corrosion prevention measures and the establishment of international collaboration for best corrosion practices, expertise, and developing standards.

Accounting for water quality in monitoring access to safe drinking-water as part of the Millennium Development Goals: lessons from five countries.

PubMed

Bain, Rob E S; Gundry, Stephen W; Wright, Jim A; Yang, Hong; Pedley, Steve; Bartram, Jamie K

2012-03-01

To determine how data on water source quality affect assessments of progress towards the 2015 Millennium Development Goal (MDG) target on access to safe drinking-water. Data from five countries on whether drinking-water sources complied with World Health Organization water quality guidelines on contamination with thermotolerant coliform bacteria, arsenic, fluoride and nitrates in 2004 and 2005 were obtained from the Rapid Assessment of Drinking-Water Quality project. These data were used to adjust estimates of the proportion of the population with access to safe drinking-water at the MDG baseline in 1990 and in 2008 made by the Joint Monitoring Programme for Water Supply and Sanitation, which classified all improved sources as safe. Taking account of data on water source quality resulted in substantially lower estimates of the percentage of the population with access to safe drinking-water in 2008 in four of the five study countries: the absolute reduction was 11% in Ethiopia, 16% in Nicaragua, 15% in Nigeria and 7% in Tajikistan. There was only a slight reduction in Jordan. Microbial contamination was more common than chemical contamination. The criterion used by the MDG indicator to determine whether a water source is safe can lead to substantial overestimates of the population with access to safe drinking-water and, consequently, also overestimates the progress made towards the 2015 MDG target. Monitoring drinking-water supplies by recording both access to water sources and their safety would be a substantial improvement.

Experimental study of solar still using local material in south of Algeria

NASA Astrophysics Data System (ADS)

Nasri., Bahous; Benatiallah, Ali; Kalloum, Slimane; Benatiallah, Djelloul

2018-05-01

South of Algeria has these last years increasing water demand associated with rapid urban development and expansion in the irrigated land have led to over-exploitation of groundwater resources, consequently, it caused a degradation of the groundwater quality by increasing its salinity. In arid areas of Algeria with a shortage of pure water and endowed with an important solar potential, solar distillation is an important alternative for the potable water production. In this study, an attempt has been made to study a novel solar still by using a local material tested under climatic conditions of Adrar city. Experiments proprieties and performance of this solar still were carried out for a long time. The measurement of solar intensity, ambient temperature, water productivity, saline water temperature, glasses temperatures inside and outside, and the distilled water quality were studied. The results show that the daily productivity was varied from 4.04 to 4.48 l/m²d. Local materials are very interesting to increase the productivity and to give a good quality of output water with a low cost. Also, the results show that the output water quality is using for drinking and in accordance with WHO standards guidelines.

Application of soil quality indices to assess the status of agricultural soils irrigated with treated wastewaters

NASA Astrophysics Data System (ADS)

Morugán-Coronado, A.; Arcenegui, V.; García-Orenes, F.; Mataix-Solera, J.; Mataix-Beneyto, J.

2012-12-01

The supply of water is limited in some parts of the Mediterranean region, such as southeastern Spain. The use of treated wastewater for the irrigation of agricultural soils is an alternative to using better-quality water, especially in semi-arid regions. On the other hand, this practice can modify some soil properties, change their relationships, the equilibrium reached and influence soil quality. In this work two soil quality indices were used to evaluate the effects of irrigation with treated wastewater in soils. The indices were developed studying different soil properties in undisturbed soils in SE Spain, and the relationships between soil parameters were established using multiple linear regressions. This study was carried out in three areas of Alicante Province (SE Spain) irrigated with wastewater, including four study sites. The results showed slight changes in some soil properties as a consequence of irrigation with wastewater, the obtained levels not being dangerous for agricultural soils, and in some cases they could be considered as positive from an agronomical point of view. In one of the study sites, and as a consequence of the low quality wastewater used, a relevant increase in soil organic matter content was observed, as well as modifications in most of the soil properties. The application of soil quality indices indicated that all the soils of study sites are in a state of disequilibrium regarding the relationships between properties independent of the type of water used. However, there were no relevant differences in the soil quality indices between soils irrigated with wastewater with respect to their control sites for all except one of the sites, which corresponds to the site where low quality wastewater was used.

Towards Sustainable Water Quality In Estuarine Impoundments: The Current State.

NASA Astrophysics Data System (ADS)

Wright, J.; Worrall, F.

Several estuarine impoundment schemes have been built or are proposed in the UK and worldwide. The impounding of estuaries is currently a popular approach to urban regeneration in the UK. By creation of an aesthetically pleasing amenity impound- ment, including the drowning of "unsightly" tidal mud flats, it is hoped that prestige development will be encouraged in the estuarine area. Impounding fundamentally alters the dynamics of estuaries, with consequences in terms of sedimentation patterns and rates, and water quality. The SIMBA Project at- tempts to understand the controls on water quality in impoundments, with a view to- wards long term and sustainable high water quality through good barrage design and management practice. Detailed water quality surveys have been carried out on a total of 79 dates on the Tees, Tawe, Wansbeck and Blyth estuaries. Water quality parameters which have been determined are pH, Eh, dissolved oxygen (DO), biochemical oxygen demand (BOD), conductivity, transparency, suspended solids, alkalinity, temperature, nutri- ents (nitrate+nitrite, ammonium and orthophosphate), and a large range of dissolved metals. Statistical analyses are used to demonstrate the major controls on water qual- ity in impoundments. A distinction is made between total tidal exclusion (freshwater) systems, in which water quality is primarily influenced by external/catchment factors, and partial tidal exclusion systems, in which water quality is processed internally. This internal processing is due to density stratification creating compartments of saline wa- ter in contact with oxygen demanding sediments and isolated from the atmosphere, which leads to conditions of low DO and changes in redox conditions which may lead to release of metals and phosphate from the sediment.

Assessment of domestic water quality: case study, Beirut, Lebanon.

PubMed

Korfali, Samira Ibrahim; Jurdi, Mey

2007-12-01

In urban cities, the environmental services are the responsibility of the public sector, where piped water supply is the norm for urban household. Likewise, in Beirut City (capital of Lebanon) official water authorities are the main supplier of domestic water through a network of piping system that leaks in many areas. Beirut City and its suburbs are overpopulated since it is the residence of 1/3 of the Lebanese citizens. Thus, Beirut suffers deficiency in meeting its water demand. Water rationing, as a remedial action, is firmly established since four decades by the Lebanese Water Authorities. Consumers resorted then to private wells to supplement their domestic water needs. Consequently, household water quality is influenced by external factors relating to well water characteristics and internal factors depending on the types of the pipes of the distribution network and cross connections to sewer pipes. These factors could result in chemical and microbial contamination of drinking water. The objective of this study is to investigate domestic water quality variation in Beirut City emerging form the aforementioned factors. The presented work encircles a typical case study of Beirut City (Ras Beirut). Results showed deterioration pattern in domestic water quality. The predicted metal species and scales within the water pipes of distribution network depended on water pH, hardness, sulfate, chloride, and iron. The corrosion of iron pipes mainly depended on Mg hardness.

Spatial and temporal variations in the relationship between lake water surface temperatures and water quality - A case study of Dianchi Lake.

PubMed

Yang, Kun; Yu, Zhenyu; Luo, Yi; Yang, Yang; Zhao, Lei; Zhou, Xiaolu

2018-05-15

Global warming and rapid urbanization in China have caused a series of ecological problems. One consequence has involved the degradation of lake water environments. Lake surface water temperatures (LSWTs) significantly shape water ecological environments and are highly correlated with the watershed ecosystem features and biodiversity levels. Analysing and predicting spatiotemporal changes in LSWT and exploring the corresponding impacts on water quality is essential for controlling and improving the ecological water environment of watersheds. In this study, Dianchi Lake was examined through an analysis of 54 water quality indicators from 10 water quality monitoring sites from 2005 to 2016. Support vector regression (SVR), Principal Component Analysis (PCA) and Back Propagation Artificial Neural Network (BPANN) methods were applied to form a hybrid forecasting model. A geospatial analysis was conducted to observe historical LSWTs and water quality changes for Dianchi Lake from 2005 to 2016. Based on the constructed model, LSWTs and changes in water quality were simulated for 2017 to 2020. The relationship between LSWTs and water quality thresholds was studied. The results show limited errors and highly generalized levels of predictive performance. In addition, a spatial visualization analysis shows that from 2005 to 2020, the chlorophyll-a (Chla), chemical oxygen demand (COD) and total nitrogen (TN) diffused from north to south and that ammonia nitrogen (NH 3 -N) and total phosphorus (TP) levels are increases in the northern part of Dianchi Lake, where the LSWT levels exceed 17°C. The LSWT threshold is 17.6-18.53°C, which falls within the threshold for nutritional water quality, but COD and TN levels fall below V class water quality standards. Transparency (Trans), COD, biochemical oxygen demand (BOD) and Chla levels present a close relationship with LSWT, and LSWTs are found to fundamentally affect lake cyanobacterial blooms. Copyright © 2017 Elsevier B.V. All rights reserved.

MERCURY MEASUREMENTS USING DIRECT-ANALYZER METHODOLOGY

EPA Science Inventory

Under EPA's Water Quality Research Program, exposure studies are needed to determine how well control strategies and guidance are working. Consequently, reliable and convenient techniques that minimize waste production are of special interest. While traditional methods for determ...

Temporal and Spatial Variation of Chemical Water Quality in a Contour Canal.

NASA Astrophysics Data System (ADS)

Swanson, L. A.; Lunn, R. J.

2004-12-01

Chemical water quality is a highly variable aspect of any water body. Historically numerous researchers have investigated the chemical variability of rivers, streams and wetlands, artificial water bodies such as canals have been largely neglected. Canals are typically hydraulically characterised by low flows and a lack of mixing processes. This can potentially lead to significant spatial variability in water chemistry, and as a result many canals in the UK regularly fail water quality targets at specific locations. Recent changes to UK legislation, following the European Water Framework Directive (2000/60/EC), have resulted in canals being subject to achieving `good ecological status'. In the case of canals, what constitutes `good ecological status' is largely unknown and little expertise is available since historically canal management has not been driven by chemical and ecological quality targets. Consequently, there is an urgent need for new research to determine the main factors influencing canal water quality and their ecological status. This research presents results from a study based on a UK contour canal, the Union Canal in central Scotland. The Union Canal typically demonstrates spatially and temporally variable levels of dissolved oxygen (DO) and orthophosphate (PO4-P): simultaneously, seasonal and diel fluctuations of DO and PO4-P are pronounced at a small number of locations. During 1995, minimum levels of DO along the canal length ranged from 9mgl-1 in Edinburgh to as low as 2mgl-1 approximately 20kms away, this then rose again to 8mgl-1 after a further distance of 2km. These acutely low levels of DO are coupled with events of excessive PO4-P up to 0.235mgl-1:10 times greater than those normally found in rivers, causing localised eutrophication and extensive fish kills. To determine the cause of the `hot spots' of poor water quality found on the Union Canal, simultaneous investigations of the hydraulic regime, spatial and temporal water quality variation and the canal's biological status were carried out. Velocity metering in the canal identified extremely low flow rates ~0.15m3s-1. A tracer testing procedure for the canal's low flow conditions was designed and implemented which identified a lack of rapid dispersion processes with D~0.133m3s-1. Water quality sampling consisted of a year-long programme of high frequency temporal and spatial sampling along the canal length. Observations demonstrate significant variability, with widely differing measurements of DO as little as 5m apart. In addition, spot samples of water quality taken from individual incoming field drains showed PO4-P concentrations up to 2mgl-1, with a predominance of nutrient bound clay and silt sediments that ultimately settle on the canal bed. Due to low dispersion rates, residence times for pollutants are long and field drains, in combination with navigational activity, may well be one of the primary causes of raised nutrient levels at some locations. This research has shown that canal water quality is highly spatially and temporally variable; far in excess of the variability normally found in river systems. This is mainly determined by a lack of hydraulic mixing and the presence of small quantities of incoming runoff water of very low quality. Whilst low in volume, incoming sediment from the drains appears to strongly influence the nearby canal water quality. These results have important consequences both for future monitoring strategies of canals and management of their gradual ecological improvement.

Selenium Supplementation Affects Physiological and Biochemical Processes to Improve Fodder Yield and Quality of Maize (Zea mays L.) under Water Deficit Conditions

PubMed Central

Nawaz, Fahim; Naeem, Muhammad; Ashraf, Muhammad Y.; Tahir, Muhammad N.; Zulfiqar, Bilal; Salahuddin, Muhammad; Shabbir, Rana N.; Aslam, Muhammad

2016-01-01

Climate change is one of the most complex challenges that pose serious threats to livelihoods of poor people who rely heavily on agriculture and livestock particularly in climate-sensitive developing countries of the world. The negative effects of water scarcity, due to climate change, are not limited to productivity food crops but have far-reaching consequences on livestock feed production systems. Selenium (Se) is considered essential for animal health and has also been reported to counteract various abiotic stresses in plants, however, understanding of Se regulated mechanisms for improving nutritional status of fodder crops remains elusive. We report the effects of exogenous selenium supply on physiological and biochemical processes that may influence green fodder yield and quality of maize (Zea mays L.) under drought stress conditions. The plants were grown in lysimeter tanks under natural conditions and were subjected to normal (100% field capacity) and water stress (60% field capacity) conditions. Foliar spray of Se was carried out before the start of tasseling stage (65 days after sowing) and was repeated after 1 week, whereas, water spray was used as a control. Drought stress markedly reduced the water status, pigments and green fodder yield and resulted in low forage quality in water stressed maize plants. Nevertheless, exogenous Se application at 40 mg L-1 resulted in less negative leaf water potential (41%) and enhanced relative water contents (30%), total chlorophyll (53%), carotenoid contents (60%), accumulation of total free amino acids (40%) and activities of superoxide dismutase (53%), catalase (30%), peroxidase (27%), and ascorbate peroxidase (27%) with respect to control under water deficit conditions. Consequently, Se regulated processes improved fodder yield (15%) and increased crude protein (47%), fiber (10%), nitrogen free extract (10%) and Se content (36%) but did not affect crude ash content in water stressed maize plants. We propose that Se foliar spray (40 mg L-1) is a handy, feasible and cost-effective approach to improve maize fodder yield and quality in arid and semi-arid regions of the world facing acute shortage of water. PMID:27729917

Environmental Consequences of the Failure of the New Orleans Levee System During Hurricane Katrina; Microbiological Analysis

DTIC Science & Technology

2007-06-01

Love, G. Lovelace, J. Stewart, and B. Robinson. 2005. Methods to detect and genotype coliphages in water and shellfish. Methodology for a demonstra... Water fecal coliform counts (colony forming units (cfu) per 100 mL of water ) ranged from 100 to 490,000 (mean=21,381, standard deviation =74,541...100) in St. Bernard Parish and the Lower Ninth Ward polders. The LADEQ primary contact recreational water quality criterion for fecal coliforms is

[Ground water improvement in the Ruhr--then and now].

PubMed

Schmidt, W D

1989-05-01

The waterworks founded during the second half of the last century obtained the raw water exclusively from the Ruhr-valley; they were responsible for the water supply of the industrial area situated on the right of the river Rhine. The rapidly growing water demand, limited possibilities in water catchment, the very bad quality of the Ruhr-water and epidemic typhoid fever required new methods in the water supply. Consequently, the Hygiene-Institute of Gelsenkirchen was founded and a new method of water production developed: the artificial ground water recharge. In 1913 two associations were founded: the Ruhrtalsperrenverein responsible for the provision of water quantity, and the Ruhrverband, responsible for the improvement of water quality. These associations formed the essential base for the rapid development of the so-called "Revier". In spite of the excellent elimination of bacteria by artificial ground water recharge-operating according to the principle of slow sand filtration-a disinfection of drinking water with chlorine became necessary; this disinfection was started in 1910 by the waterworks of the Ruhr. The construction of reservoirs and clarification plants ameliorated temporary the overall situation in water resources management. These improvements were, however, destroyed by consequences arising from the rapid economical growth before the second world war and the following break-down. After this period, great efforts were necessary to enlarge the reservoirs and increase the capacity of sewage plants. The waterworks pre-purified the water from the Ruhr before infiltration into the underground in order to increase the quantity and quality of the recharged water. Downstream, the number of sewage plants increased; a more and more refined method of analysis indicates now the pollution load of the raw ater and signalized trends which lead to further treatment measures or to the change of existing ones like substitution of chlorine by chlorine-dioxide. The artificial ground water recharge-because of its many advantages-should always be the nucleus of water treatment of the river Ruhr. For the sake of the natural character of water catchment and in order not to degrade the waterworks to mere "water-manufacturers", we are all requested to handle thoroughly and cautiously water-endangering substances.

Water Quality Index for measuring drinking water quality in rural Bangladesh: a cross-sectional study.

PubMed

Akter, Tahera; Jhohura, Fatema Tuz; Akter, Fahmida; Chowdhury, Tridib Roy; Mistry, Sabuj Kanti; Dey, Digbijoy; Barua, Milan Kanti; Islam, Md Akramul; Rahman, Mahfuzar

2016-02-09

Public health is at risk due to chemical contaminants in drinking water which may have immediate health consequences. Drinking water sources are susceptible to pollutants depending on geological conditions and agricultural, industrial, and other man-made activities. Ensuring the safety of drinking water is, therefore, a growing problem. To assess drinking water quality, we measured multiple chemical parameters in drinking water samples from across Bangladesh with the aim of improving public health interventions. In this cross-sectional study conducted in 24 randomly selected upazilas, arsenic was measured in drinking water in the field using an arsenic testing kit and a sub-sample was validated in the laboratory. Water samples were collected to test water pH in the laboratory as well as a sub-sample of collected drinking water was tested for water pH using a portable pH meter. For laboratory testing of other chemical parameters, iron, manganese, and salinity, drinking water samples were collected from 12 out of 24 upazilas. Drinking water at sample sites was slightly alkaline (pH 7.4 ± 0.4) but within acceptable limits. Manganese concentrations varied from 0.1 to 5.5 mg/L with a median value of 0.2 mg/L. The median iron concentrations in water exceeded WHO standards (0.3 mg/L) at most of the sample sites and exceeded Bangladesh standards (1.0 mg/L) at a few sample sites. Salinity was relatively higher in coastal districts. After laboratory confirmation, arsenic concentrations were found higher in Shibchar (Madaripur) and Alfadanga (Faridpur) compared to other sample sites exceeding WHO standard (0.01 mg/L). Of the total sampling sites, 33 % had good-quality water for drinking based on the Water Quality Index (WQI). However, the majority of the households (67 %) used poor-quality drinking water. Higher values of iron, manganese, and arsenic reduced drinking water quality. Awareness raising on chemical contents in drinking water at household level is required to improve public health.

Quantifying Impact of Biofeedstock Production on Hydrology/Water Quality in Midwest USA

NASA Astrophysics Data System (ADS)

Chaubey, Indrajeet; Engel, Bernard; Thomas, Mark; Raj, Cibin; Saraswat, Dharmendra

2010-05-01

The production of biofeedstocks for biofuels is likely to impact the hydrology and water quality of watersheds. Communities potentially impacted are increasingly concerned, and at present, little is known regarding the magnitude of impacts of biofeedstock production on hydrology and water quality. We have initiated a national facilitation project to answer the following questions: What are the unintended environmental consequences of increased corn production to meet biofuel demands? What are the environmental impacts of various second generation biofeedstock production systems to meet cellulosic ethanol demands? Would the management of cropping systems involving corn silage meet cellulosic ethanol demands with minimal environmental impact? What are the broad-scale water quality implications of energy crops, such as switchgrass, grown for bioenergy production on highly erodible soils? This presentation will discuss development of multi-regional agricultural land management practices that can be implemented to mitigate potential negative environmental impacts associated with biofeedstock production while meeting the biofuel production demand. Specifically, we will discuss how watershed scale modeling can be utilized to evaluate the environmental impacts of various biofeedstock production strategies. We will also discuss regional differences in alternative biofeedstock production and associated hydrologic/water quality impacts.

Evaluation of military field-water quality: Volume 9, Data for assessing health risks in potential theaters of operation for US military forces: (Final report)

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

Daniels, J.I.; Layton, D.W.

1988-02-01

Data are presented in this volume for assessing the health risks in populations of military personnel that could result as a consequence of exposure to field waters containing constituents or infectious organisms of military concern, which are from natural and anthropogenic sources, at levels above those recommended as field-water-quality standards (i.e., above safe levels). Turbidity and color are the physical properties that are of military concern in field water. The other constituents that are of military concern in field water are (1) total dissolved solids, (2) chloride, (3) magnesium, (4) sulfate, (5) arsenic, (6) cyanide, (7) the pesticide lindane, andmore » (8) metabolites of algae and associated bacteria. Bacteria, viruses, and parasites (e.g., protozoa and helminths) are categories of water-related infectious organisms that are of military concern. Figures were developed from dose-response data to enable military risk managers to quickly assess the potential performance-degrading effects in personnel exposed to a measured concentration of a particular constituent in field water. The general physical, chemical, and biological quality of field waters in geographic regions worldwide, representing potential theaters of operation for U.S. military forces, also are evaluated. This analysis is based on available water-quality monitoring data and indicators of likely water-quality conditions (e.g., geohydrology, climate, sanitation, industrialization, etc.). Accompanying our evaluation are maps and tables alerting military planners and risk managers to the physical, chemical, or biological quality of field water that can be expected generally in geographic regions of concern.« less

Accounting for water quality in monitoring access to safe drinking-water as part of the Millennium Development Goals: lessons from five countries

PubMed Central

Bain, Rob ES; Wright, Jim A; Yang, Hong; Pedley, Steve; Bartram, Jamie K

2012-01-01

Abstract Objective To determine how data on water source quality affect assessments of progress towards the 2015 Millennium Development Goal (MDG) target on access to safe drinking-water. Methods Data from five countries on whether drinking-water sources complied with World Health Organization water quality guidelines on contamination with thermotolerant coliform bacteria, arsenic, fluoride and nitrates in 2004 and 2005 were obtained from the Rapid Assessment of Drinking-Water Quality project. These data were used to adjust estimates of the proportion of the population with access to safe drinking-water at the MDG baseline in 1990 and in 2008 made by the Joint Monitoring Programme for Water Supply and Sanitation, which classified all improved sources as safe. Findings Taking account of data on water source quality resulted in substantially lower estimates of the percentage of the population with access to safe drinking-water in 2008 in four of the five study countries: the absolute reduction was 11% in Ethiopia, 16% in Nicaragua, 15% in Nigeria and 7% in Tajikistan. There was only a slight reduction in Jordan. Microbial contamination was more common than chemical contamination. Conclusion The criterion used by the MDG indicator to determine whether a water source is safe can lead to substantial overestimates of the population with access to safe drinking-water and, consequently, also overestimates the progress made towards the 2015 MDG target. Monitoring drinking-water supplies by recording both access to water sources and their safety would be a substantial improvement. PMID:22461718

Climate change impacts on marine water quality: The case study of the Northern Adriatic sea.

PubMed

Rizzi, J; Torresan, S; Critto, A; Zabeo, A; Brigolin, D; Carniel, S; Pastres, R; Marcomini, A

2016-01-30

Climate change is posing additional pressures on coastal ecosystems due to variations in water biogeochemical and physico-chemical parameters (e.g., pH, salinity) leading to aquatic ecosystem degradation. With the main aim of analyzing the potential impacts of climate change on marine water quality, a Regional Risk Assessment methodology was developed and applied to coastal marine waters of the North Adriatic. It integrates the outputs of regional biogeochemical and physico-chemical models considering future climate change scenarios (i.e., years 2070 and 2100) with site-specific environmental and socio-economic indicators. Results showed that salinity and temperature will be the main drivers of changes, together with macronutrients, especially in the area of the Po' river delta. The final outputs are exposure, susceptibility and risk maps supporting the communication of the potential consequences of climate change on water quality to decision makers and stakeholders and provide a basis for the definition of adaptation and management strategies. Copyright © 2015 Elsevier Ltd. All rights reserved.

Influence of the South-North Water Diversion Project and the mitigation projects on the water quality of Han River.

PubMed

Zhu, Y P; Zhang, H P; Chen, L; Zhao, J F

2008-11-15

Situated in the central part of China, the Han River Basin is undergoing rapid social and economic development with some human interventions to be made soon which will profoundly influence the water environment of the basin. The integrated MIKE 11 model system comprising of a rainfall-runoff model (NAM), a non-point load evaluation model (LOAD), a hydrodynamic model (MIKE 11 HD) and a water quality model (ECOLab) was applied to investigate the impact of the Middle Route of the South-North Water Diversion Project on the Han River and the effectiveness of the 2 proposed mitigation projects, the 22 wastewater treatment plants (WWTPs) and the Yangtze-Han Water Diversion Project. The study concludes that business as usual will lead to a continuing rapid deterioration of the water quality of the Han River. Implementation of the Middle Route of the South-North Water Diversion Project in 2010 will bring disastrous consequence in the form of the remarkably elevated pollution level and high risk of algae bloom in the middle and lower reaches. The proposed WWTPs will merely lower the pollution level in the reach by around 10%, while the Yangtze-Han Water Diversion Project can significantly improve the water quality in the downstream 200-km reach. The results reveal that serious water quality problem will emerge in the middle reach between Xiangfan and Qianjiang in the future. Implementation of the South-North Water Diversion Project (phase II) in 2030 will further exacerbate the problem. In order to effectively improve the water quality of the Han River, it is suggested that nutrient removal processes should be adopted in the proposed WWTPs, and the pollution load from the non-point sources, especially the load from the upstream Henan Province, should be effectively controlled.

A decision support system for drinking water production integrating health risks assessment.

PubMed

Delpla, Ianis; Monteith, Donald T; Freeman, Chris; Haftka, Joris; Hermens, Joop; Jones, Timothy G; Baurès, Estelle; Jung, Aude-Valérie; Thomas, Olivier

2014-07-18

The issue of drinking water quality compliance in small and medium scale water services is of paramount importance in relation to the 98/83/CE European Drinking Water Directive (DWD). Additionally, concerns are being expressed over the implementation of the DWD with respect to possible impacts on water quality from forecast changes in European climate with global warming and further anticipated reductions in north European acid emissions. Consequently, we have developed a decision support system (DSS) named ARTEM-WQ (AwaReness Tool for the Evaluation and Mitigation of drinking Water Quality issues resulting from environmental changes) to support decision making by small and medium plant operators and other water stakeholders. ARTEM-WQ is based on a sequential risk analysis approach that includes consideration of catchment characteristics, climatic conditions and treatment operations. It provides a holistic evaluation of the water system, while also assessing human health risks of organic contaminants potentially present in treated waters (steroids, pharmaceuticals, pesticides, bisphenol-a, polychlorobiphenyls, polycyclic aromatic hydrocarbons, petrochemical hydrocarbons and disinfection by-products; n = 109). Moreover, the system provides recommendations for improvement while supporting decision making in its widest context. The tool has been tested on various European catchments and shows a promising potential to inform water managers of risks and appropriate mitigative actions. Further improvements should include toxicological knowledge advancement, environmental background pollutant concentrations and the assessment of the impact of distribution systems on water quality variation.

Legislation and policy for the protection of the drinking water supply in The Netherlands.

PubMed

van Dijk-Looijaard, A M; de Kruijf, H A

1985-12-01

The drinking water supply in The Netherlands is particularly influenced by the pollution of surface water with organic micropollutants as the country is located at the delta of the polluted rivers Rhine and Meuse. Also ground water pollution, resulting from intensive industrial and agricultural activities in this densely populated country, is becoming increasingly important. Consequently the Dutch Government has great interest in international research, discussions and agreements concerning the protection of raw water sources. This paper summarizes the drinking water quality regulations together with the present legislation and activities carried out for the protection of both surface water and ground water. Most measures are now taken in the international frameworks of the EC (European Community) or IRC (International Rhine Commission), but in the Dutch legislation and sanitation policy additional activities are being carried out to safeguard the quality of drinking water in The Netherlands. Finally the policy of the Dutch government to continue the safe and durable provision of drinking water in the future is discussed.

Climate change and drinking water production in The Netherlands: a flexible approach.

PubMed

Ramaker, T A B; Meuleman, A F M; Bernhardi, L; Cirkel, G

2005-01-01

Climate change increases water system dynamics through temperature changes, changes in precipitation patterns, evaporation, water quality and water storage in ice packs. Water system dependent economical stakeholders, such as drinking water companies in The Netherlands, have to cope with consequences of climate change, e.g. floods and water shortages in river systems, upconing brackish ground water, salt water intrusion, increasing peak demands and microbiological activity. In the past decades, however, both water systems and drinking water production have become more and more inflexible; water systems have been heavily regulated and the drinking water supply has grown into an inflexible, but cheap and reliable, system. Flexibility and adaptivity are solutions to overcome climate change related consequences. Flexible adaptive strategies for drinking water production comprise new sources for drinking water production, application of storage concepts in the short term, and a redesign of large centralised systems, including flexible treatment plants, in the long term. Transition to flexible concepts will take decades because investment depreciation periods of assets are long. This implies that long-term strategies within an indicated time path have to be developed. These strategies must be based on thorough knowledge of current assets to seize opportunities for change.

Drought allocations using the Systems Impact Assessment Model: Klamath River

USGS Publications Warehouse

Flug, M.; Campbell, S.G.

2005-01-01

Water supply and allocation scenarios for the Klamath River, Ore. and Calif., were evaluated using the Systems Impact Assessment Model (SIAM), a decision support system developed by the U.S. Geological Survey. SIAM is a set of models with a graphical user interface that simulates water supply and delivery in a managed river system, water quality, and fish production. Simulation results are presented for drought conditions, one aspect of Klamath River water operations. The Klamath River Basin has experienced critically dry conditions in 1992, 1994, and 2001. Drought simulations are useful to estimate the impacts of specific legal or institutional flow constraints. In addition, simulations help to identify potential adverse water quality consequences including evaluating the potential for reducing adverse temperature impacts on anadromous fish. In all drought simulations, water supply was insufficient to fully meet upstream and downstream targets for endangered species.

Assessing watershed-wildfire risks on National Forest System lands in the Rocky Mountain Region of the United States

Treesearch

Matthew P. Thompson; Joe Scott; Paul G. Langowski; Julie W. Gilbertson-Day; Jessica R. Haas; Elise M. Bowne

2013-01-01

Wildfires can cause significant negative impacts to water quality with resultant consequences for the environment and human health and safety, as well as incurring substantial rehabilitation and water treatment costs. In this paper we will illustrate how state-of-the-art wildfire simulation modeling and geospatial risk assessment methods can be brought to bear to...

Modelling the impact of future socio-economic and climate change scenarios on river microbial water quality.

PubMed

Islam, M M Majedul; Iqbal, Muhammad Shahid; Leemans, Rik; Hofstra, Nynke

2018-03-01

Microbial surface water quality is important, as it is related to health risk when the population is exposed through drinking, recreation or consumption of irrigated vegetables. The microbial surface water quality is expected to change with socio-economic development and climate change. This study explores the combined impacts of future socio-economic and climate change scenarios on microbial water quality using a coupled hydrodynamic and water quality model (MIKE21FM-ECOLab). The model was applied to simulate the baseline (2014-2015) and future (2040s and 2090s) faecal indicator bacteria (FIB: E. coli and enterococci) concentrations in the Betna river in Bangladesh. The scenarios comprise changes in socio-economic variables (e.g. population, urbanization, land use, sanitation and sewage treatment) and climate variables (temperature, precipitation and sea-level rise). Scenarios have been developed building on the most recent Shared Socio-economic Pathways: SSP1 and SSP3 and Representative Concentration Pathways: RCP4.5 and RCP8.5 in a matrix. An uncontrolled future results in a deterioration of the microbial water quality (+75% by the 2090s) due to socio-economic changes, such as higher population growth, and changes in rainfall patterns. However, microbial water quality improves under a sustainable scenario with improved sewage treatment (-98% by the 2090s). Contaminant loads were more influenced by changes in socio-economic factors than by climatic change. To our knowledge, this is the first study that combines climate change and socio-economic development scenarios to simulate the future microbial water quality of a river. This approach can also be used to assess future consequences for health risks. Copyright © 2017 The Authors. Published by Elsevier GmbH.. All rights reserved.

Inactive supply wells as conduits for flow and contaminant migration: conditions of occurrence and suggestions for management

NASA Astrophysics Data System (ADS)

Gailey, Robert M.

2017-11-01

Water supply wells can act as conduits for vertical flow and contaminant migration between water-bearing strata under common hydrogeologic and well construction conditions. While recognized by some for decades, there is little published data on the magnitude of flows and extent of resulting water quality impacts. Consequently, the issue may not be acknowledged widely enough and the need for better management persists. This is especially true for unconsolidated alluvial groundwater basins that are hydrologically stressed by agricultural activities. Theoretical and practical considerations indicate that significant water volumes can migrate vertically through wells. The flow is often downward, with shallow groundwater, usually poorer in quality, migrating through conduit wells to degrade deeper water quality. Field data from locations in California, USA, are presented in combination with modeling results to illustrate both the prevalence of conditions conducive to intraborehole flow and the resulting impacts to water quality. Suggestions for management of planned wells include better enforcement of current regulations and more detailed consideration of hydrogeologic conditions during design and installation. A potentially greater management challenge is presented by the large number of existing wells. Monitoring for evidence of conduit flow and solute transport in areas of high well density is recommended to identify wells that pose greater risks to water quality. Conduit wells that are discovered may be addressed through approaches that include structural modification and changes in operations.

The Mao Ethic and Environmental Quality

ERIC Educational Resources Information Center

Orleans, Leo A.; Suttmeier, Richard P.

1970-01-01

Reviews reports on efforts to improve the Communist Chinese natural environment. National campaigns for water and air pollution control, sanitation improvement, and industrial development are related to Mao Tse-tung's philosophy of frugality and comprehensive resource use. Concern is expressed regarding possible ecological consequences from…

Standardised survey method for identifying catchment risks to water quality.

PubMed

Baker, D L; Ferguson, C M; Chier, P; Warnecke, M; Watkinson, A

2016-06-01

This paper describes the development and application of a systematic methodology to identify and quantify risks in drinking water and recreational catchments. The methodology assesses microbial and chemical contaminants from both diffuse and point sources within a catchment using Escherichia coli, protozoan pathogens and chemicals (including fuel and pesticides) as index contaminants. Hazard source information is gathered by a defined sanitary survey process involving use of a software tool which groups hazards into six types: sewage infrastructure, on-site sewage systems, industrial, stormwater, agriculture and recreational sites. The survey estimates the likelihood of the site affecting catchment water quality, and the potential consequences, enabling the calculation of risk for individual sites. These risks are integrated to calculate a cumulative risk for each sub-catchment and the whole catchment. The cumulative risks process accounts for the proportion of potential input sources surveyed and for transfer of contaminants from upstream to downstream sub-catchments. The output risk matrices show the relative risk sources for each of the index contaminants, highlighting those with the greatest impact on water quality at a sub-catchment and catchment level. Verification of the sanitary survey assessments and prioritisation is achieved by comparison with water quality data and microbial source tracking.

Applications of Geographic Information System (GIS) analysis of Lake Uluabat.

PubMed

Hacısalihoğlu, Saadet; Karaer, Feza; Katip, Aslıhan

2016-06-01

Lake Uluabat is one of the most important wetlands in Turkey because of its rich biodiversity, lying on a migratory bird route with almost all its shores being covered by submerged plants. The lake has been protected by the Ramsar Convention since 1998. However, the Lake is threatened by natural and anthropogenic stressors as a consequence of its location. Geographic Information System (GIS) analysis is a tool that has been widely used, especially for water quality management in recent years. This study aimed to investigate the water quality and determined most polluted points using GIS analysis of the lake. Temperature, pH, dissolved oxygen, chemical oxygen demand, Kjeldahl nitrogen, total phosphorus, chlorophyll-a, arsenic, boron, iron, and manganese were monitored monthly from June 2008 to May 2009, with the samples taken from 8 points in the lake. Effect of pH, relation of temperature, and Chl-a with other water quality parameters and metals are designated as statistically significant. Data were mapped using ArcGIS 9.1 software and were assessed according to the Turkish Water Pollution Control Regulations (TWPCR). The research also focused on classifying and mapping the water quality in the lake by using the spatial analysis functions of GIS. As a result, it was determined that Lake Uluabat belonged to the 4th class, i.e., highly polluted water, including any water of lower quality. A remarkable portion of the pollution in the water basin was attributed to domestic wastewater discharges, industrial and agricultural activities, and mining.

Application of automated measurement stations for continuous water quality monitoring of the Dender river in Flanders, Belgium.

PubMed

Vandenberghe, V; Goethals, P L M; Van Griensven, A; Meirlaen, J; De Pauw, N; Vanrolleghem, P; Bauwens, W

2005-09-01

During the summer of 1999, two automated water quality measurement stations were installed along the Dender river in Belgium. The variables dissolved oxygen, temperature, conductivity, pH, rain-intensity, flow and solar radiation were measured continuously. In this paper these on-line measurement series are presented and interpreted using also additional measurements and ecological expert-knowledge. The purpose was to demonstrate the variability in time and space of the aquatic processes and the consequences of conducting and interpreting discrete measurements for river quality assessment and management. The large fluctuations of the data illustrated the importance of continuous measurements for the complete description and modelling of the biological processes in the river.

Workshop: Market Mechanisms and Incentives: Applications to Environmental Policy (2009-part 3)

EPA Pesticide Factsheets

Presentations on the use of market mechanisms and incentives in the areas of fuel economy, water quality, land use and the distributional consequences of using market incentives. There was also a panel discussion on the role of market mechanisms on climate

A Decision Support System for Drinking Water Production Integrating Health Risks Assessment

PubMed Central

Delpla, Ianis; Monteith, Donald T.; Freeman, Chris; Haftka, Joris; Hermens, Joop; Jones, Timothy G.; Baurès, Estelle; Jung, Aude-Valérie; Thomas, Olivier

2014-01-01

The issue of drinking water quality compliance in small and medium scale water services is of paramount importance in relation to the 98/83/CE European Drinking Water Directive (DWD). Additionally, concerns are being expressed over the implementation of the DWD with respect to possible impacts on water quality from forecast changes in European climate with global warming and further anticipated reductions in north European acid emissions. Consequently, we have developed a decision support system (DSS) named ARTEM-WQ (AwaReness Tool for the Evaluation and Mitigation of drinking Water Quality issues resulting from environmental changes) to support decision making by small and medium plant operators and other water stakeholders. ARTEM-WQ is based on a sequential risk analysis approach that includes consideration of catchment characteristics, climatic conditions and treatment operations. It provides a holistic evaluation of the water system, while also assessing human health risks of organic contaminants potentially present in treated waters (steroids, pharmaceuticals, pesticides, bisphenol-a, polychlorobiphenyls, polycyclic aromatic hydrocarbons, petrochemical hydrocarbons and disinfection by-products; n = 109). Moreover, the system provides recommendations for improvement while supporting decision making in its widest context. The tool has been tested on various European catchments and shows a promising potential to inform water managers of risks and appropriate mitigative actions. Further improvements should include toxicological knowledge advancement, environmental background pollutant concentrations and the assessment of the impact of distribution systems on water quality variation. PMID:25046634

Water use benefit index as a tool for community-based monitoring of water related trends in the Great Barrier Reef region

NASA Astrophysics Data System (ADS)

Smajgl, A.; Larson, S.; Hug, B.; De Freitas, D. M.

2010-12-01

SummaryThis paper presents a tool for documenting and monitoring water use benefits in the Great Barrier Reef catchments that allows temporal and spatial comparison along the region. Water, water use benefits and water allocations are currently receiving much attention from Australian policy makers and conservation practitioners. Because of the inherent complexity and variability in water quality, it is essential that scientific information is presented in a meaningful way to policy makers, managers and ultimately, to the general public who have to live with the consequences of the decisions. We developed an inexpensively populated and easily understandable water use benefit index as a tool for community-based monitoring of water related trends in the Great Barrier Reef region. The index is developed based on a comparative list of selected water-related indices integrating attributes across physico-chemical, economic, social, and ecological domains currently used in the assessment of water quality, water quantity and water use benefits in Australia. Our findings indicate that the proposed index allows the identification of water performance indicators by temporal and spatial comparisons. Benefits for decision makers and conservation practitioners include a flexible way of prioritization towards the domain with highest concern. The broader community benefits from a comprehensive and user-friendly tool, communicating changes in water quality trends more effectively.

Identification of water quality degradation hotspots in developing countries by applying large scale water quality modelling

NASA Astrophysics Data System (ADS)

Malsy, Marcus; Reder, Klara; Flörke, Martina

2014-05-01

Decreasing water quality is one of the main global issues which poses risks to food security, economy, and public health and is consequently crucial for ensuring environmental sustainability. During the last decades access to clean drinking water increased, but 2.5 billion people still do not have access to basic sanitation, especially in Africa and parts of Asia. In this context not only connection to sewage system is of high importance, but also treatment, as an increasing connection rate will lead to higher loadings and therefore higher pressure on water resources. Furthermore, poor people in developing countries use local surface waters for daily activities, e.g. bathing and washing. It is thus clear that water utilization and water sewerage are indispensable connected. In this study, large scale water quality modelling is used to point out hotspots of water pollution to get an insight on potential environmental impacts, in particular, in regions with a low observation density and data gaps in measured water quality parameters. We applied the global water quality model WorldQual to calculate biological oxygen demand (BOD) loadings from point and diffuse sources, as well as in-stream concentrations. Regional focus in this study is on developing countries i.e. Africa, Asia, and South America, as they are most affected by water pollution. Hereby, model runs were conducted for the year 2010 to draw a picture of recent status of surface waters quality and to figure out hotspots and main causes of pollution. First results show that hotspots mainly occur in highly agglomerated regions where population density is high. Large urban areas are initially loading hotspots and pollution prevention and control become increasingly important as point sources are subject to connection rates and treatment levels. Furthermore, river discharge plays a crucial role due to dilution potential, especially in terms of seasonal variability. Highly varying shares of BOD sources across regions, and across sectors demand for an integrated approach to assess main causes of water quality degradation.

The Water Quality in Rio Highlights the Global Public Health ...

EPA Pesticide Factsheets

Water quality issues in Rio have been widely publicized because of the 2016 Olympics. Recent concerns about polluted waters that athletes may be exposed to highlights the conditions that more than a billion people globally are exposed to daily. Despite these unhealthy conditions, much is unknown about the risks and exposure pathways associated with bathing in or drinking untreated or partially treated sewage. Beyond acute illness, we are learning more about the chronic sequelae that arise from repeated exposure to pathogens found in sewage. Additionally, we do not know enough about how to measure water quality, especially in developing countries. A consequence of these knowledge gaps is that data from developed countries are used to guide public health approaches in low· and middle-income settings. More data that are locally specific are needed to inform guidelines for improving sanitation and water quality in Rio and other cities in developing countries. Recent media reports of high levels of sewage contamination have caused wide-ranging concerns about the safety of sailing, rowing, and other open water events at the upcoming Olympics. This commentary discusses the global public health problem of exposures to untreated sewage and describes the need for context specific solutions to monitoring and communication and risk assessment.

Towards a Real-Time Embedded System for Water Monitoring Installed in a Robotic Sailboat

PubMed Central

da Silva Junior, Andouglas Goncalves; de Lima Sa, Sarah Thomaz; dos Santos, Davi Henrique; de Negreiros, Álvaro Pinto Ferrnandes; de Souza Silva, João Moreno Vilas Boas; Álvarez Jácobo, Justo Emílio; Garcia Gonçalves, Luiz Marcos

2016-01-01

Problems related to quality (and quantity) of water in natural resources or in artificial reservoirs are frequently arising and are at the center of attention of authorities and governments around the world. Many times the monitoring is not performed in an efficient time frame and a precise manner, whereas the adoption of fast and punctual solutions would undoubtedly improve the water quality and consequently enhance the life of people. To minimize or diminish such kinds of problems, we propose an architecture for sensors installed in a robotic platform, an autonomous sail boat, able to acquire raw data relative to water quality, to process and make them available to people that might be interested in such information. The main contributions are the sensors architecture itself, which uses low cost sensors, with practical experimentation done with a prototype. Results show data collected for points in lakes and rivers in the northeast of Brazil. This embedded system is fixed in the sailboat robot with the intention to facilitate the study of water quality for long endurance missions. This robot can help monitoring water bodies in a more consistent manner. Nonetheless the system can also be used with fixed vases or buoys in strategic points. PMID:27509506

When climate change is a fact! Adaptive strategies for drinking water production in a changing natural environment.

PubMed

Meuleman, A F M; Cirkel, G; Zwolsman, G J J

2007-01-01

Climate change increases water system dynamics through temperature changes, changes in precipitation patterns, evaporation, and water quality and water storage in ice packs. Water system dependent economical stakeholders, such as drinking water companies in the Netherlands, have to cope with consequences of climate change, e.g. floods and water shortages in river systems, upcoming of brackish ground water, salt water intrusion, increasing peak demands and microbiological activity due to temperature rise. In the past decades, however, both water systems and drinking water production have become more and more inflexible; water systems have been heavily regulated aiming at maximum security and economic functions and the drinking water supply in the Netherlands has grown into an inflexible, but cheap and reliable, system. At a water catchment scale, flexibility and adaptation are solutions to overcome climate change related consequences. Flexible adaptive strategies for drinking water production comprise new sources for drinking water production, application of storage concepts in the short term, and a redesign of large centralized systems, including flexible treatment plants, in the long term. Transition to flexible concepts will take decades because investment depreciation periods of assets are long. These strategies must be based on thorough knowledge of current assets to seize opportunities for change.

Desert basins of the Southwest

USGS Publications Warehouse

Leake, Stanley A.; Konieczki, Alice D.; Rees, Julie A.H.

2000-01-01

Ground water is among the Nation’s most important natural resources. It provides drinking water to urban and rural communities, supports irrigation and industry, sustains the flow of streams and rivers, and maintains riparian and wetland ecosystems. In many areas of the Nation, the future sustainability of ground-water resources is at risk from overuse and contamination. Because ground-water systems typically respond slowly to human actions, a long-term perspective is needed to manage this valuable resource. This publication is one in a series of fact sheets that describe ground-water-resource issues across the United States, as well as some of the activities of the U.S. Geological Survey that provide information to help others develop, manage, and protect ground-water resources in a sustainable manner. Ground-water resources in the Southwest are among the most overused in the United States. Natural recharge to aquifers is low and pumping in many areas has resulted in lowering of water tables. The consequences of large-scale removal of water from storage are becoming increasingly evident. These consequences include land subsidence; loss of springs, streams, wetlands and associated habitat; and degradation of water quality. Water managers are now seeking better ways of managing ground-water resources while looking for supplemental sources of water. This fact sheet reviews basic information on ground water in the desert basins of the Southwest. Also described are some activities of the U.S. Geological Survey (USGS) that are providing scientific information for sustainable management of ground-water resources in the Southwest. Ground-water sustainability is defined as developing and using ground water in a way that can be maintained for an indefinite time without causing unacceptable environmental, economic, or social consequences.

The implications of drought and water conservation on the reuse of municipal wastewater: Recognizing impacts and identifying mitigation possibilities.

PubMed

Tran, Quynh K; Jassby, David; Schwabe, Kurt A

2017-11-01

As water agencies continue to investigate opportunities to increase resilience and local water supply reliability in the face of drought and rising water scarcity, water conservation strategies and the reuse of treated municipal wastewater are garnering significant attention and adoption. Yet a simple water balance thought experiment illustrates that drought, and the conservation strategies that are often enacted in response to it, both likely limit the role reuse may play in improving local water supply reliability. For instance, as a particular drought progresses and agencies enact water conservation measures to cope with drought, influent flows likely decrease while influent pollution concentrations increase, particularly salinity, which adversely affects wastewater treatment plant (WWTP) costs and effluent quality and flow. Consequently, downstream uses of this effluent, whether to maintain streamflow and quality, groundwater recharge, or irrigation may be impacted. This is unfortunate since reuse is often heralded as a drought-proof mechanism to increase resilience. The objectives of this paper are two-fold. First, we illustrate-using a case study from Southern California during its most recent drought- how drought and water conservation strategies combine to reduce influent flow and quality and, subsequently, effluent flow and quality. Second, we use a recently developed regional water reuse decision support model (RWRM) to highlight cost-effective strategies that can be implemented to mitigate the impacts of drought on effluent water quality. While the solutions we identify cannot increase the flow of influent or effluent coming into or out of a treatment plant, they can improve the value of the remaining effluent in a cost-effective manner that takes into account the characteristics of its demand, whether it be for landscaping, golf courses, agricultural irrigation, or surface water augmentation. Copyright © 2017 Elsevier Ltd. All rights reserved.

Assessment of the Impacts of Climate Change on Stream Discharge and Water Quality in an Arid, Urbanized Watershed

NASA Astrophysics Data System (ADS)

Ranatunga, T.; Tong, S.; Yang, J.

2011-12-01

Hydrologic and water quality models can provide a general framework to conceptualize and investigate the relationships between climate and water resources. Under a hot and dry climate, highly urbanized watersheds are more vulnerable to changes in climate, such as excess heat and drought. In this study, a comprehensive watershed model, Hydrological Simulation Program FORTRAN (HSPF), is used to assess the impacts of future climate change on the stream discharge and water quality in Las Vegas Wash in Nevada, the only surface water body that drains from the Las Vegas Valley (an area with rapid population growth and urbanization) to Lake Mead. In this presentation, the process of model building, calibration and validation, the generation of climate change scenarios, and the assessment of future climate change effects on stream hydrology and quality are demonstrated. The hydrologic and water quality model is developed based on the data from current national databases and existing major land use categories of the watershed. The model is calibrated for stream discharge, nutrients (nitrogen and phosphorus) and sediment yield. The climate change scenarios are derived from the outputs of the Global Climate Models (GCM) and Regional Climate Models (RCM) simulations, and from the recent assessment reports from the Intergovernmental Panel on Climate Change (IPCC). The Climate Assessment Tool from US EPA's BASINS is used to assess the effects of likely future climate scenarios on the water quantity and quality in Las Vegas Wash. Also the presentation discusses the consequences of these hydrologic changes, including the deficit supplies of clean water during peak seasons of water demand, increased eutrophication potentials, wetland deterioration, and impacts on wild life habitats.

Land cover impacts on stream nutrients and fecal coliform in the lower Piedmont of West Georgia

NASA Astrophysics Data System (ADS)

Schoonover, Jon E.; Lockaby, B. Graeme

2006-12-01

SummaryAs urbanization infiltrates into rural areas, stream water quality is expected to decline as a result from increased impervious surface and greater sources for pollutants. Consequently, West Georgia's water quality is threatened by extensive development as well as other land uses such as livestock grazing and silvicultural activity. Maintenance of stream water quality, as land development occurs, is critical for the protection of drinking water and biotic integrity. A 2-phase, watershed-scale study was established to develop relationships among land cover and water quality within western Georgia. During phase 1, nutrient and fecal coliform data were collected within 18 mixed land use watersheds, ranging in size from 500 to 2500 ha. Regression models were developed that related land cover to stream water nutrient and fecal coliform concentrations. Nutrient and fecal coliform concentrations within watersheds having >24% impervious surface (IS) were often higher than those in nonurban watersheds (i.e., <5% IS) during both base flow (N: 1.64 mg/L versus 0.61 mg/L, and FC: 430 versus 120 MPN/100 ml) and storm flow (N: 1.93 mg/L versus 0.36 mg/L, and FC: 1600 versus 167 MPN/100 ml). Fecal coliform bacteria in urbanized areas consistently exceeded the US EPA's review criterion for recreational waters during both base flow and to a greater extent storm flow. During phase 2, regression models were tested based on data from six newly chosen watersheds with similar land use/cover patterns. Lastly, theoretical watersheds, based on land use percentages, were created to illustrate trends in water quality impairment as land development occurs. The models developed from this research could be used to forecast water quality changes under various land use scenarios in the developing Piedmont region of the US.

Impacts of biodiversity loss on ocean ecosystem services.

PubMed

Worm, Boris; Barbier, Edward B; Beaumont, Nicola; Duffy, J Emmett; Folke, Carl; Halpern, Benjamin S; Jackson, Jeremy B C; Lotze, Heike K; Micheli, Fiorenza; Palumbi, Stephen R; Sala, Enric; Selkoe, Kimberley A; Stachowicz, John J; Watson, Reg

2006-11-03

Human-dominated marine ecosystems are experiencing accelerating loss of populations and species, with largely unknown consequences. We analyzed local experiments, long-term regional time series, and global fisheries data to test how biodiversity loss affects marine ecosystem services across temporal and spatial scales. Overall, rates of resource collapse increased and recovery potential, stability, and water quality decreased exponentially with declining diversity. Restoration of biodiversity, in contrast, increased productivity fourfold and decreased variability by 21%, on average. We conclude that marine biodiversity loss is increasingly impairing the ocean's capacity to provide food, maintain water quality, and recover from perturbations. Yet available data suggest that at this point, these trends are still reversible.

Water mass interaction in the confluence zone of the Daning River and the Yangtze River--a driving force for algal growth in the Three Gorges Reservoir.

PubMed

Holbach, Andreas; Wang, Lijing; Chen, Hao; Hu, Wei; Schleicher, Nina; Zheng, Binghui; Norra, Stefan

2013-10-01

Increasing eutrophication and algal bloom events in the Yangtze River Three Gorges Reservoir, China, are widely discussed with regard to changed hydrodynamics and nutrient transport and distribution processes. Insights into water exchange and interaction processes between water masses related to large-scale water level fluctuations in the reservoir are crucial to understand water quality and eutrophication dynamics. Therefore, confluence zones of tributaries with the Yangtze River main stream are dedicated key interfaces. In this study, water quality data were recorded in situ and on-line in varying depths with the MINIBAT towed underwater multi-sensor system in the confluence zone of the Daning River and the Yangtze River close to Wushan City during 1 week in August 2011. Geostatistical evaluation of the water quality data was performed, and results were compared to phosphorus contents of selective water samples. The strongly rising water level throughout the measurement period caused Yangtze River water masses to flow upstream into the tributary and supply their higher nutrient and particulate loads into the tributary water body. Rapid algal growth and sedimentation occurred immediately when hydrodynamic conditions in the confluence zone became more serene again. Consequently, water from the Yangtze River main stream can play a key role in providing nutrients to the algal bloom stricken water bodies of its tributaries.

Water quality assessment in terms of water quality index (WQI): case study of the Kolong River, Assam, India

NASA Astrophysics Data System (ADS)

Bora, Minakshi; Goswami, Dulal C.

2017-10-01

The Kolong River of Nagaon district, Assam has been facing serious degradation leading to its current moribund condition due to a drastic human intervention in the form of an embankment put across it near its take-off point from the Brahmaputra River in the year 1964. The blockage of the river flow was adopted as a flood control measure to protect its riparian areas, especially the Nagaon town, from flood hazard. The river, once a blooming distributary of the mighty Brahmaputra, had high navigability and rich riparian biodiversity with a well established agriculturally productive watershed. However, the present status of Kolong River is highly wretched as a consequence of the post-dam effects thus leaving it as stagnant pools of polluted water with negligible socio-economic and ecological value. The Central Pollution Control Board, in one of its report has placed the Kolong River among 275 most polluted rivers of India. Thus, this study is conducted to analyze the seasonal water quality status of the Kolong River in terms of water quality index (WQI). The WQI scores shows very poor to unsuitable quality of water samples in almost all the seven sampling sites along the Kolong River. The water quality is found to be most deteriorated during monsoon season with an average WQI value of 122.47 as compared to pre-monsoon and post-monsoon season having average WQI value of 85.73 and 80.75, respectively. Out of the seven sampling sites, Hatimura site (S1) and Nagaon Town site (S4) are observed to be the most polluted sites.

Physico-Chemical and Microbial Analysis of Selected Borehole Water in Mahikeng, South Africa.

PubMed

Palamuleni, Lobina; Akoth, Mercy

2015-07-23

Groundwater is generally considered a "safe source" of drinking water because it is abstracted with low microbial load with little need for treatment before drinking. However, groundwater resources are commonly vulnerable to pollution, which may degrade their quality. An assessment of microbial and physicochemical qualities of borehole water in the rural environs of Mahikeng town, South Africa, was carried out. The study aimed at determining levels of physicochemical (temperature, pH, turbidity and nitrate) and bacteriological (both faecal and total coliform bacteria) contaminants in drinking water using standard microbiology methods. Furthermore, identities of isolates were determined using the API 20E assay. Results were compared with World Health Organisation (WHO) and Department of Water Affairs (DWAF-SA) water quality drinking standards. All analyses for physicochemical parameters were within acceptable limits except for turbidity while microbial loads during spring were higher than the WHO and DWAF thresholds. The detection of Escherichia coli, Salmonella and Klebsiella species in borehole water that was intended for human consumption suggests that water from these sources may pose severe health risks to consumers and is unsuitable for direct human consumption without treatment. The study recommends mobilisation of onsite treatment interventions to protect the households from further possible consequences of using the water.

Physico-Chemical and Microbial Analysis of Selected Borehole Water in Mahikeng, South Africa

PubMed Central

Palamuleni, Lobina; Akoth, Mercy

2015-01-01

Groundwater is generally considered a “safe source” of drinking water because it is abstracted with low microbial load with little need for treatment before drinking. However, groundwater resources are commonly vulnerable to pollution, which may degrade their quality. An assessment of microbial and physicochemical qualities of borehole water in the rural environs of Mahikeng town, South Africa, was carried out. The study aimed at determining levels of physicochemical (temperature, pH, turbidity and nitrate) and bacteriological (both faecal and total coliform bacteria) contaminants in drinking water using standard microbiology methods. Furthermore, identities of isolates were determined using the API 20E assay. Results were compared with World Health Organisation (WHO) and Department of Water Affairs (DWAF-SA) water quality drinking standards. All analyses for physicochemical parameters were within acceptable limits except for turbidity while microbial loads during spring were higher than the WHO and DWAF thresholds. The detection of Escherichia coli, Salmonella and Klebsiella species in borehole water that was intended for human consumption suggests that water from these sources may pose severe health risks to consumers and is unsuitable for direct human consumption without treatment. The study recommends mobilisation of onsite treatment interventions to protect the households from further possible consequences of using the water. PMID:26213950

Human health and groundwater

USDA-ARS?s Scientific Manuscript database

The high quality of most groundwaters, consequent upon the self-purification capacity of subsurface strata, has long been a key factor in human health and wellbeing. More than 50% of the world’s population now rely on groundwater for their supply of drinking water – and in most circumstances a prope...

A classification of freshwater Louisiana lakes based on water quality and user perception data.

PubMed

Burden, D G; Malone, R F

1987-09-01

An index system developed for Louisiana lakes was based on correlations between measurable water quality parameters and perceived lake quality. Support data was provided by an extensive monitoring program of 30 lakes coordinated with opinion surveys undertaken during summer 1984. Lakes included in the survey ranged from 4 to 735 km(2) in surface area with mean depths ranging from 0.5 to 8.0 m. Water quality data indicated most of these lakes are eutrophic, although many have productive fisheries and are considered recreational assets. Perception ratings of fishing quality and its associated water quality were obtained by distributing approximately 1200 surveys to Louisiana Bass Club Associaton members. The ability of Secchi disc transparency, total organic carbon, total Kjeldahl nitrogen, total phosphorus, and chlorophyll a to discriminate between perception classes was examined using probability distributions and multivariate analyses. Secchi disc and total organic carbon best reflected perceived lake conditions; however, these parameters did not provide the discrimination necessary for developing a quantitative risk assessment of lake trophic state. Consequently, an interim lakes index system was developed based on total organic carbon and perceived lake conditions. The developed index system will aid State officials in interpretating and evaluating regularly collected lake quality data, recognizing potential problem areas, and identifying proper management policies for protecting fisheries usage within the State.

Continuous water-quality and suspended-sediment transport monitoring in the San Francisco Bay, California, water years 2011–13

USGS Publications Warehouse

Buchanan, Paul A.; Downing-Kunz, Maureen; Schoellhamer, David H.; Shellenbarger, Gregory; Weidich, Kurt

2014-01-01

The U.S. Geological Survey (USGS) monitors water quality and suspended-sediment transport in the San Francisco Bay. The San Francisco Bay area is home to millions of people, and the bay teems with both resident and migratory wildlife, plants, and fish. Fresh water mixes with salt water in the bay, which is subject both to riverine and marine (tides, waves, influx of salt water) influences. To understand this environment, the USGS, along with its partners, has been monitoring the bay’s waters continuously since 1988. Several water-quality variables are of particular importance to State and Federal resource managers and are monitored at key locations throughout the bay. Salinity, which indicates the relative mixing of fresh and ocean waters in the bay, is derived from specific conductance measurements. Water temperature, along with salinity, affects the density of water, which causes gravity driven circulation patterns and stratification in the water column. Turbidity is measured using light-scattering from suspended solids in water, and is used as a surrogate for suspended-sediment concentration (SSC). Suspended sediment often carries adsorbed contaminants; attenuates sunlight in the water column; deposits on tidal marsh and intertidal mudflats, which can help sustain these habitats as sea level rises; and deposits in ports and shipping channels, which can necessitate dredging. Dissolved oxygen, which is essential to a healthy ecosystem, is a fundamental indicator of water quality, and its concentration is affected by water temperature, salinity, ecosystem metabolism, tidal currents, and wind. Tidal currents in the bay reverse four times a day, and wind direction and intensity typically change on a daily cycle: consequently, salinity, water temperature, suspendedsediment concentration, and dissolvedoxygen concentration vary spatially and temporally throughout the bay, and continuous measurements are needed to observe these changes. The purpose of this fact sheet is to inform the public and resource managers of the availability of these water-quality data.

Impact of short-term climate variation and hydrology change on thermal structure and water quality of a canyon-shaped, stratified reservoir.

PubMed

Ma, Wei-Xing; Huang, Ting-Lin; Li, Xuan; Zhang, Hai-Han; Ju, Tuo

2015-12-01

Climate variation can have obvious effects on hydrologic conditions, which in turn can have direct consequences for the thermal regime and quality of water for human use. In this research, weekly surveys were conducted from 2011 to 2013 to investigate how changes of climate and hydrology affect the thermal regime and water quality at the Heihe Reservoir. Our results show that the hydrology change during the flooding season can both increase the oxygen concentration and accelerate the consumption of dissolved oxygen. Continuous heavy rainfall events occurred in September 2011 caused the mixing of the entire reservoir, which led to an increase in dissolved oxygen at the bottom until the next year. Significant turbid density flow was observed following the extreme rainfall events in 2012 which leading to a rapid increase in turbidity at the bottom (up to 3000 NTU). Though the dissolved oxygen at the bottom increased from 0 to 9.02 mg/L after the rainfall event, it became anoxic within 20 days due to the increase of water oxygen demand caused by the suspended matter brought by the storm runoff. The release of compounds from the sediments was more serious during the anaerobic period after the rainfall events and the concentration of total iron, total phosphorus, and total manganese at the bottom reached 1.778, 0.102, and 0.125 mg/L. The improved water-lifting aerators kept on running after the storm runoff occurred in 2013 to avoid the deterioration of water quality during anaerobic conditions and ensured the good water quality during the mixing period. Our results suggest preventive and remediation actions that are necessary to improve water quality and status.

Factors Affecting Source-Water Quality after Disturbance of Forests by Wildfire

NASA Astrophysics Data System (ADS)

Murphy, S. F.; Martin, D. A.; McCleskey, R. B.; Writer, J. H.

2015-12-01

Forests yield high-quality water supplies to communities throughout the world, in part because forest cover reduces flooding and the consequent transport of suspended and dissolved constituents to surface water. Disturbance by wildfire reduces or eliminates forest cover, leaving watersheds susceptible to increased surface runoff during storms and reduced ability to retain contaminants. We assessed water-quality response to hydrologic events for three years after a wildfire in the Fourmile Creek Watershed, near Boulder, Colorado, and found that hydrologic and geochemical responses downstream of a burned area were primarily driven by small, brief convective storms that had relatively high, but not unusual, rainfall intensity. Total suspended sediment, dissolved organic carbon, nitrate, and manganese concentrations were 10-156 times higher downstream of a burned area compared to upstream, and water quality was sufficiently impaired to pose water-treatment concerns. The response in both concentration and yield of water-quality constituents differed depending on source availability and dominant watershed processes controlling the constituent. For example, while all constituent concentrations were highest during storm events, annual sediment yields downstream of the burned area were controlled by storm events and subsequent mobilization, whereas dissolved organic carbon yields were more dependent on spring runoff from upstream areas. The watershed response was affected by a legacy of historical disturbance: the watershed had been recovering from extensive disturbance by mining, railroad and road development, logging, and fires in the late 19th and early 20th centuries, and we observed extensive erosion of mine waste in response to these summer storms. Therefore, both storm characteristics and historical disturbance in a burned watershed must be considered when evaluating the role of wildfire on water quality.

The valuation of water quality: effects of mixing different drinking water qualities.

PubMed

Rygaard, Martin; Arvin, Erik; Binning, Philip J

2009-03-01

As water supplies increasingly turn to use desalination technologies it becomes relevant to consider the options for remineralization and blending with mineral rich water resources. We present a method for analyzing economic consequences due to changes in drinking water mineral content. Included impacts are cardiovascular diseases, dental caries, atopic eczema, lifetime of dish and clothes washing machines, heat exchangers, distribution systems, bottled water consumption and soap usage. The method includes an uncertainty assessment that ranks the impacts having the highest influence on the result and associated uncertainty. Effects are calculated for a scenario where 50% of Copenhagen's water supply is substituted by desalinated water. Without remineralization the total impact is expected to be negative (euro -0.44+/-0.2/m(3)) and individual impacts expected in the range of euro 0.01-0.51/m(3) delivered water. Health impacts have the highest contribution to impact size and uncertainty. With remineralization it is possible to reduce several negative impacts and the total impact is expected to be positive (euro 0.14+/-0.08/m(3)).

Consequences of Climate Change, Eutrophication, and Other Anthropogenic Impacts to Coastal Salt Marshes: Multiple Stressors Reduce Resiliency and Sustainability

EPA Science Inventory

Coastal salt marshes provide a wide variety of ecosystem services, including habitat for protected vertebrates and ecologically valuable invertebrate fauna, flood protection, and improvements in water quality for adjacent marine and estuarine environments. Here, we consider the ...

A SIMPLE MODEL FOR FORECASTING THE EFFECTS OF NITROGEN LOADS ON CHESAPEAKE BAY HYPOXIA

EPA Science Inventory

The causes and consequences of oxygen depletion in Chesapeake Bay have been the focus of research, assessment, and policy action over the past several decades. An ongoing scientific re-evaluation of what nutrients load reductions are necessary to meet the water quality goals is ...

Water technology for specific water usage.

PubMed

Frimmel, Fritz H

2003-01-01

Water is the basis for life and culture. In addition to the availability of water its quality has become a major issue in industrialized areas and in developing countries as well. Water usage has to be seen as part of the hydrological cycle. As a consequence water management has to be sustainable. The aim of the contribution is to give water usage oriented quality criteria and to focus on the technical means to achieve them. Water is used for many purposes, ranging from drinking and irrigation to a broad variety of technical processes. Most applications need specific hygienic, chemical and/or physical properties. To meet these demands separation and reaction principles are applied. The reuse of water and the application of water treatment with little or no waste and by-product formation is the way to go. Membrane separation and advanced oxidation including catalytic reactions are promising methods that apply natural processes in sustainable technical performance. Thus elimination of specific water constituents (e.g. salts and metals, microorganisms) and waste water cleaning (e.g. pollutants, nutrients and organic water) can be done efficiently. Learning from nature and helping nature with appropriate technology is a convincing strategy for sustainable water management.

Climate change, water resources and child health.

PubMed

Kistin, Elizabeth J; Fogarty, John; Pokrasso, Ryan Shaening; McCally, Michael; McCornick, Peter G

2010-07-01

Climate change is occurring and has tremendous consequences for children's health worldwide. This article describes how the rise in temperature, precipitation, droughts, floods, glacier melt and sea levels resulting from human-induced climate change is affecting the quantity, quality and flow of water resources worldwide and impacting child health through dangerous effects on water supply and sanitation, food production and human migration. It argues that paediatricians and healthcare professionals have a critical leadership role to play in motivating and sustaining efforts for policy change and programme implementation at the local, national and international level.

Identification, assessment, and control of hazards in water supply: experiences from Water Safety Plan implementations in Germany.

PubMed

Mälzer, H-J; Staben, N; Hein, A; Merkel, W

2010-01-01

According to the recommendations of the World Health Organization (WHO) for Water Safety Plans (WSP), a Technical Risk Management was developed, which considers standard demands in drinking water treatment in Germany. It was already implemented at several drinking water treatment plants of different size and treatment processes in Germany. Hazards affecting water quality, continuity, and the reliability of supply from catchment to treatment and distribution could be identified by a systematic approach, and suitable control measures were defined. Experiences are presented by detailed examples covering methods, practical consequences, and further outcomes. The method and the benefits for the water suppliers are discussed and an outlook on the future role of WSPs in German water supply is given.

Categorical Indicator Kriging for assessing the risk of groundwater nitrate pollution: the case of Vega de Granada aquifer (SE Spain).

PubMed

Chica-Olmo, Mario; Luque-Espinar, Juan Antonio; Rodriguez-Galiano, Victor; Pardo-Igúzquiza, Eulogio; Chica-Rivas, Lucía

2014-02-01

Groundwater nitrate pollution associated with agricultural activity is an important environmental problem in the management of this natural resource, as acknowledged by the European Water Framework Directive. Therefore, specific measures aimed to control the risk of water pollution by nitrates must be implemented to minimise its impact on the environment and potential risk to human health. The spatial probability distribution of nitrate contents exceeding a threshold or limit value, established within the quality standard, will be helpful to managers and decision-makers. A methodology based on non-parametric and non-linear methods of Indicator Kriging was used in the elaboration of a nitrate pollution categorical map for the aquifer of Vega de Granada (SE Spain). The map has been obtained from the local estimation of the probability that a nitrate content in an unsampled location belongs to one of the three categories established by the European Water Framework Directive: CL. 1 good quality [Min - 37.5 ppm], CL. 2 intermediate quality [37.5-50 ppm] and CL. 3 poor quality [50 ppm - Max]. The obtained results show that the areas exceeding nitrate concentrations of 50 ppm, poor quality waters, occupy more than 50% of the aquifer area. A great proportion of the area's municipalities are located in these poor quality water areas. The intermediate quality and good quality areas correspond to 21% and 28%, respectively, but with the highest population density. These results are coherent with the experimental data, which show an average nitrate concentration value of 72 ppm, significantly higher than the quality standard limit of 50 ppm. Consequently, the results suggest the importance of planning actions in order to control and monitor aquifer nitrate pollution. © 2013.

Climate Adaptation Capacity for Conventional Drinking Water Treatment Facilities

NASA Astrophysics Data System (ADS)

Levine, A.; Goodrich, J.; Yang, J.

2013-12-01

Water supplies are vulnerable to a host of climate- and weather-related stressors such as droughts, intense storms/flooding, snowpack depletion, sea level changes, and consequences from fires, landslides, and excessive heat or cold. Surface water resources (lakes, reservoirs, rivers, and streams) are especially susceptible to weather-induced changes in water availability and quality. The risks to groundwater systems may also be significant. Typically, water treatment facilities are designed with an underlying assumption that water quality from a given source is relatively predictable based on historical data. However, increasing evidence of the lack of stationarity is raising questions about the validity of traditional design assumptions, particularly since the service life of many facilities can exceed fifty years. Given that there are over 150,000 public water systems in the US that deliver drinking water to over 300 million people every day, it is important to evaluate the capacity for adapting to the impacts of a changing climate. Climate and weather can induce or amplify changes in physical, chemical, and biological water quality, reaction rates, the extent of water-sediment-air interactions, and also impact the performance of treatment technologies. The specific impacts depend on the watershed characteristics and local hydrological and land-use factors. Water quality responses can be transient, such as erosion-induced increases in sediment and runoff. Longer-term impacts include changes in the frequency and intensity of algal blooms, gradual changes in the nature and concentration of dissolved organic matter, dissolved solids, and modulation of the microbiological community structure, sources and survival of pathogens. In addition, waterborne contaminants associated with municipal, industrial, and agricultural activities can also impact water quality. This presentation evaluates relationships between climate and weather induced water quality variability and the capacity of treatment facilities and supporting water infrastructure to deliver safe drinking water consistently and reliably. Simulation models of water treatment facilities are used to evaluate the outcome of specific source water quality scenarios on treatment system performance and reliability. Modeling results are used to evaluate the process and operational capacity to respond to transient water quality changes and adapt to longer-term variability in water quality and availability. In some cases, changes in temperature and mineral content serve to improve the overall treatment performance. In addition, the integration of microbially enhanced treatment systems such as biological filtration can provide additional capacity. Conversely, changes in the nutrient and temperature dynamics can trigger algal and cyanobacterial blooms that can impair performance. Research needs are identified and the importance of developing more integrated modeling systems is highlighted.

Does the bathing water classification depend on sampling strategy? A bootstrap approach for bathing water quality assessment, according to Directive 2006/7/EC requirements.

PubMed

López, Iago; Alvarez, César; Gil, José L; Revilla, José A

2012-11-30

Data on the 95th and 90th percentiles of bacteriological quality indicators are used to classify bathing waters in Europe, according to the requirements of Directive 2006/7/EC. However, percentile values and consequently, classification of bathing waters depend both on sampling effort and sample-size, which may undermine an appropriate assessment of bathing water classification. To analyse the influence of sampling effort and sample size on water classification, a bootstrap approach was applied to 55 bacteriological quality datasets of several beaches in the Balearic Islands (Spain). Our results show that the probability of failing the regulatory standards of the Directive is high when sample size is low, due to a higher variability in percentile values. In this way, 49% of the bathing waters reaching an "Excellent" classification (95th percentile of Escherichia coli under 250 cfu/100 ml) can fail the "Excellent" regulatory standard due to sampling strategy, when 23 samples per season are considered. This percentage increases to 81% when 4 samples per season are considered. "Good" regulatory standards can also be failed in bathing waters with an "Excellent" classification as a result of these sampling strategies. The variability in percentile values may affect bathing water classification and is critical for the appropriate design and implementation of bathing water Quality Monitoring and Assessment Programs. Hence, variability of percentile values should be taken into account by authorities if an adequate management of these areas is to be achieved. Copyright © 2012 Elsevier Ltd. All rights reserved.

Hydraulic design to optimize the treatment capacity of Multi-Stage Filtration units

NASA Astrophysics Data System (ADS)

Mushila, C. N.; Ochieng, G. M.; Otieno, F. A. O.; Shitote, S. M.; Sitters, C. W.

2016-04-01

Multi-Stage Filtration (MSF) can provide a robust treatment alternative for surface water sources of variable water quality in rural communities at low operation and maintenance costs. MSF is a combination of Slow Sand Filters (SSFs) and Pre-treatment systems. The general objective of this research was to optimize the treatment capacity of MSF. A pilot plant study was undertaken to meet this objective. The pilot plant was monitored for a continuous 98 days from commissioning till the end of the project. Three main stages of MSF namely: The Dynamic Gravel Filter (DGF), Horizontal-flow Roughing Filter (HRF) and SSF were identified, designed and built. The response of the respective MSF units in removal of selected parameters guiding drinking water quality such as microbiological (Faecal and Total coliform), Suspended Solids, Turbidity, PH, Temperature, Iron and Manganese was investigated. The benchmark was the Kenya Bureau (KEBS) and World Health Organization (WHO) Standards for drinking water quality. With respect to microbiological raw water quality improvement, MSF units achieved on average 98% Faecal and 96% Total coliform removal. Results obtained indicate that implementation of MSF in rural communities has the potential to increase access to portable water to the rural populace with a probable consequent decrease in waterborne diseases. With a reduced down time due to illness, more time would be spent in undertaking other economic activities.

Expected Improvements in the Quantitative Remote Sensing of Optically Complex Waters with the Use of an Optically Fast Hyperspectral Spectrometer—A Modeling Study

PubMed Central

Moses, Wesley J.; Bowles, Jeffrey H.; Corson, Michael R.

2015-01-01

Using simulated data, we investigated the effect of noise in a spaceborne hyperspectral sensor on the accuracy of the atmospheric correction of at-sensor radiances and the consequent uncertainties in retrieved water quality parameters. Specifically, we investigated the improvement expected as the F-number of the sensor is changed from 3.5, which is the smallest among existing operational spaceborne hyperspectral sensors, to 1.0, which is foreseeable in the near future. With the change in F-number, the uncertainties in the atmospherically corrected reflectance decreased by more than 90% across the visible-near-infrared spectrum, the number of pixels with negative reflectance (caused by over-correction) decreased to almost one-third, and the uncertainties in the retrieved water quality parameters decreased by more than 50% and up to 92%. The analysis was based on the sensor model of the Hyperspectral Imager for the Coastal Ocean (HICO) but using a 30-m spatial resolution instead of HICO’s 96 m. Atmospheric correction was performed using Tafkaa. Water quality parameters were retrieved using a numerical method and a semi-analytical algorithm. The results emphasize the effect of sensor noise on water quality parameter retrieval and the need for sensors with high Signal-to-Noise Ratio for quantitative remote sensing of optically complex waters. PMID:25781507

The use of biomarkers as integrative tools for transitional water bodies monitoring in the Water Framework Directive context - A holistic approach in Minho river transitional waters.

PubMed

Capela, R; Raimundo, J; Santos, M M; Caetano, M; Micaelo, C; Vale, C; Guimarães, L; Reis-Henriques, M A

2016-01-01

The Water Framework Directive (WFD) provides an important legislative opportunity to promote and implement an integrated approach for the protection of inland surface waters, transitional waters, coastal waters and groundwaters. The transitional waters constitute a central piece as they are usually under high environmental pressure and by their inherent characteristics present monitoring challenges. Integrating water quality monitoring with biological monitoring can increase the cost-effectiveness of monitoring efforts. One way of doing this is with biomarkers, which effectively integrate physical-chemical status and biological quality elements, dealing holistically with adverse consequences on the health of water bodies. The new Marine Strategy Framework Directive (MSFD) already incorporates the biomarker approach. Given the recent activities of OSPAR and HELCOM to harmonize existing monitoring guidelines between MSFD and WFD the use of similar methodologies should be fostered. To illustrate the potential of the biomarker approach, juveniles of flounder (Platichthys flesus) were used to evaluate the quality of the Minho river-estuary water bodies. The use of juveniles instead of adults eliminates several confounding factors such changes on the biological responses associated with reproduction. Here, a panel of well-established biomarkers, EROD, AChE, SOD, CAT, GST, LPO, ENA and FACs (1-Hydroxyrene) were selected and measured along with a gradient of different physical conditions, and integrated with trace elements characterization on both biota and sediments. In general, a clear profile along the water bodies was found, with low seasonal and spatial variation, consistent with a low impacted area. Overall, the results support the use of both the battery of biomarkers and the use of juvenile flounders in the monitoring of the water quality status within the WFD. Copyright © 2015 Elsevier B.V. All rights reserved.

Development of water quality thresholds during dredging for the protection of benthic primary producer habitats.

PubMed

Sofonia, Jeremy J; Unsworth, Richard K F

2010-01-01

Given the potential for adverse effects of ocean dredging on marine organisms, particularly benthic primary producer communities, the management and monitoring of those activities which cause elevated turbidity and sediment loading is critical. In practice, however, this has proven challenging as the development of water quality threshold values, upon which management responses are based, are subject to a large number of physical and biological parameters that are spatially and temporally specific. As a consequence, monitoring programs to date have taken a wide range of different approaches, most focusing on measures of turbidity reported as nephelometric turbidity units (NTU). This paper presents a potential approach in the determination of water quality thresholds which utilises data gathered through the long-term deployment of in situ water instruments, but suggests a focus on photosynthetic active radiation (PAR) rather than NTU as it is more relevant biologically and inclusive of other site conditions. A simple mathematical approach to data interpretation is also presented which facilitates threshold value development, not individual values of concentrations over specific intervals, but as an equation which may be utilized in numerical modelling.

Personality, Foraging and Fitness Consequences in a Long Lived Seabird

PubMed Central

Patrick, Samantha C.; Weimerskirch, Henri

2014-01-01

While personality differences in animals are defined as consistent behavioural variation between individuals, the widely studied field of foraging specialisation in marine vertebrates has rarely been addressed within this framework. However there is much overlap between the two fields, both aiming to measure the causes and consequences of consistent individual behaviour. Here for the first time we use both a classic measure of personality, the response to a novel object, and an estimate of foraging strategy, derived from GPS data, to examine individual personality differences in black browed albatross and their consequences for fitness. First, we examine the repeatability of personality scores and link these to variation in foraging habitat. Bolder individuals forage nearer the colony, in shallower regions, whereas shyer birds travel further from the colony, and fed in deeper oceanic waters. Interestingly, neither personality score predicted a bird’s overlap with fisheries. Second, we show that both personality scores are correlated with fitness consequences, dependent on sex and year quality. Our data suggest that shyer males and bolder females have higher fitness, but the strength of this relationship depends on year quality. Females who forage further from the colony have higher breeding success in poor quality years, whereas males foraging close to the colony always have higher fitness. Together these results highlight the potential importance of personality variation in seabirds and that the fitness consequences of boldness and foraging strategy may be highly sex dependent. PMID:24504180

Framework for a ground-water quality monitoring and assessment program for California

USGS Publications Warehouse

Belitz, Kenneth; Dubrovsky, Neil M.; Burow, Karen; Jurgens, Bryant C.; John, Tyler

2003-01-01

The State of California uses more ground water than any other State in the Nation. With a population of over 30 million people, an agricultural economy based on intensive irrigation, large urban industrial areas, and naturally elevated concentrations of some trace elements, there is a wide range of contaminant sources that have the potential to contaminate ground water and limit its beneficial uses. In response to the many-and different-potential sources of ground-water contamination, the State of California has evolved an extensive set of rules and programs to protect ground-water quality, and agencies to implement the rules and programs. These programs have in common a focus on compliance with regulations governing chemical use and (or) ground-water quality. Although appropriate for, and successful at, their specific missions, these programs do not at present provide a comprehensive view of ground-water quality in the State of California. In October 2001, The California Assembly passed a bill, AB 599, establishing the Ground-Water- Quality Monitoring Act of 2001.' The goal of AB 599 is to improve Statewide comprehensive ground-water monitoring and increase availability of information about ground-water quality to the public. AB 599 requires the State Water Resources Control Board (SWRCB), in collaboration with an interagency task force (ITF) and a public advisory committee (PAC), to develop a plan for a comprehensive ground-water monitoring program. AB 599 specifies that the comprehensive program should be capable of assessing each ground-water basin in the State through direct and other statistically reliable sampling approaches, and that the program should integrate existing monitoring programs and design new program elements, as necessary. AB 599 also stresses the importance of prioritizing ground-water basins that provide drinking water. The United States Geological Survey (USGS), in cooperation with the SWRCB, and in coordination with the ITF and PAC, has developed a framework for a comprehensive ground-water-quality monitoring and assessment program for California. The proposed framework relies extensively on previous work conducted by the USGS through its National Water-Quality Assessment (NAWQA) program. In particular, the NAWQA program defines three types of ground-water assessment: (1) status, the assessment of the current quality of the ground-water resource; (2) trends, the detection of changes in water quality, and (3) understanding, assessing the human and natural factors that affect ground-water quality. A Statewide, comprehensive ground-water quality-monitoring and assessment program is most efficiently accomplished by applying uniform and consistent study-design and data-collection protocols to the entire State. At the same time, a comprehensive program should be relevant at a variety of scales, and therefore needs to retain flexibility to address regional and local issues. Consequently, many of the program components include a predominant element that will be consistently applied in all basins, and a secondary element that may be applied in specific basins where local conditions warrant attention.

Simulated Impacts of El Nino/Southern Oscillation on United States Water Resources

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

Thomson, Allison M.; Brown, Robert A.; Rosenberg, Norman J.

The El Nino/Southern Oscillation alters global weather patterns with consequences for fresh water quality and supply. ENSO events impact regions and natural resource sectors around the globe. For example, in 1997-98, a strong El Ni?o brought warm ocean temperatures, flooding and record snowfall to the west coast of the US. Research on ENSO events and their impacts has improved long range weather predictions, potentially reducing the damage and economic cost of these anomalous weather patterns. Here, we simulate the impacts of four types of ENSO states on water resources in the conterminous United States. We distinguish between Neutral, El Ni?o,more » La Ni?a and strong El Ni?o years over the period of 1960-1989. Using climate statistics that characterize these ENSO states to drive the HUMUS water resources model, we examine the effects of 'pure' ENSO events, without complications from transition periods. Strong El Ni?o is not simply an amplification of El Ni?o; it leads to strikingly different consequences for climate and water resources.« less

Health impairments arising from drinking water polluted with domestic sewage and excreta in China.

PubMed

Ling, B

2000-01-01

Raw water of poor quality still causes many drinking-water associated health problems all over China, largely because of poor sanitation, inadequate disposal of sewage and excreta. Eutrophication due to excess of total nitrogen and phosphorous in some sources for drinking-water has led to massive proliferation of cyanobacteria. The dominant species of cyanophyta can produce microcystins, a potent liver cancer promotor. As in previous studies, high incidence of liver cancer coincided with high microcystin concentration in the source water, especially in pond water. A frequent consequence of heavy pollution of source water is further the high incidence of infectious intestinal diseases, which are more than 10-100 times as frequent in China than in developed countries.

ECOLOGICAL AND WATER QUALITY CONSEQUENCES OF NUTRIENT ADDITION FOR SALMON RESTORATION IN THE PACIFIC NORTHWEST OF NORTH AMERICA

EPA Science Inventory

Salmon runs have declined over the past two centuries in the Pacific Northwest region of North America. Reduced inputs of salmon-derived organic matter and nutrients (SDN) may limit freshwater production and thus establish a negative feedback loop affecting future generations of...

AT THE INTERSECTION OF HYDROLOGY, ECONOMICS, AND LAW: APPLICATION OF MARKET MECHANISMS AND INCENTIVES TO REDUCE STORMWATER RUNOFF

EPA Science Inventory

Increased stormwater flows are a direct result of urbanization and the consequent increase in the proportion of land area under impervious surface. Due to its contribution to abnormally high stream flows and its role as a carrier of pollutants that degrade water quality, exc...

Changes in Production and Nutrient Cycling across a Wetness Gradient within a Floodplain Forest

Treesearch

Robin G. Clawson; B. Graeme Lockaby; Bob Rummer

2001-01-01

Floodplain forest ecosystems are highly valuable to society because of their potential for water quality improvement and vegetation productivity, among many other functions. Previous studies have indicated that hydrology influences productivity but that the relationship between hydroperiod and productivity is a complex one. Consequently, we compared multiple indexes of...

APPLICATION OF MARKET MECHANISMS AND INCENTIVES TO REDUCE STORMWATER RUNOFF. AN INTEGRATED HYDROLOGIC, ECONOMIC AND LEGAL APPROACH.

EPA Science Inventory

Increased stormwater flows are a direct result of urbanization and the consequent increase in the proportion of land area under impervious surface. Due to its contribution to abnormally high stream flows and its role as a carrier of pollutants that degrade water quality, excess s...

A landscape based, systems dynamic model for assessing impacts of urban development on water quality for sustainable seagrass growth in Tampa Bay, Florida

EPA Science Inventory

We present an integrated assessment model to predict potential unintended consequences of urban development on the sustainability of seagrasses and preservation of ecosystem services, such as catchable fish, in Tampa Bay. Ecosystem services are those ecological functions and pro...

The Impact of Urban Development on the Water Quality in the Las Vegas Watershed

NASA Astrophysics Data System (ADS)

Yu, A.; Simmons, C.; Acharya, K.

2009-12-01

Las Vegas, one of the fastest growing cities in the nation, must have its water strictly monitored for quality as well as degree of pollution. Samples at various sites were collected to analyze the current pollution status of our water bodies (in both residential and urban settings) in the Las Vegas watershed. These gathered samples (sediment and water) were collected and analyzed for measuring total phosphorus, total organic carbon, trace metal contents, i.e., selenium, arsenic, mercury and lead, as well as pathogens, i.e., E-coli and total coliform counts. The concentrations of various pollutions will be compared among different sites as well as natural local sites (due to the natural occurrence of a few trace metals and normal levels of other measurements) and analyzed for spatial distribution for source identification and for elucidating the cause and consequence. Preliminary analyses of the results indicate that nonpoint source pollutions (golf courses, construction sites, etc.) have larger impacts than point source pollutions such as wastewater treatment effluents. This study will help understand and evaluate the degradation of the water quality caused by the increase of human actions in recent years in Las Vegas.

Study of different pretreatments for reverse osmosis reclamation of a petrochemical secondary effluent.

PubMed

Benito-Alcázar, C; Vincent-Vela, M C; Gozálvez-Zafrilla, J M; Lora-García, J

2010-06-15

Conventionally treated petrochemical wastewaters contain substantial quantities of hazardous pollutants. In addition, wastewater reuse is being enhanced as a consequence of the shortage of fresh water. Advanced petrochemical wastewater treatment for water reuse will reduce hazardous pollutants discharges as well as water consumption. Reverse osmosis is a suitable technology to obtain pure water. This work studies the adequacy of different pretreatments applied to a petrochemical secondary effluent to produce a suitable feeding for reverse osmosis treatment. The permeate obtained can be used in the petrochemical industry for different processes. In this work, several experiments (granulated activated carbon filtration, ultrafiltration, nanofiltration and granulated activated carbon filtration coupled with nanofiltration) were performed to improve the conventional pretreatment. Total organic carbon, chemical oxygen demand, turbidity and silt density index were used to evaluate water quality for reverse osmosis feeding. In granulated activated carbon filtration, all the measured parameters but silt density index indicated a good filtrate quality to feed reverse osmosis membranes. Although the ultrafiltration permeate obtained was suitable for reverse osmosis, nanofiltration and granulated activated carbon filtration coupled with NF provided a better effluent quality for reverse osmosis than the other pretreatments studied. Copyright 2010 Elsevier B.V. All rights reserved.

Hurricane Katrina Impact on Water Quality in the East Pearl River, Mississippi

NASA Astrophysics Data System (ADS)

Shiller, A. M.; Shim, M.; Guo, L.; Bianchi, T. S.; Smith, R. W.; Duan, S.

2010-12-01

Hurricanes and other intense storms have previously been reported to cause short term changes in surface water quality. We examined the water quality of the East Pearl River in southern Mississippi both before and after Hurricane Katrina caused extensive damage to the watershed in 2005. Our post-storm sampling began two months after the hurricane, and thus we missed any immediate short-term consequences. However, sampling over the following two years allowed us to examine whether damage to watershed resulted in significant longer term effects on water quality. Interpretation of the time series data is complicated by the natural seasonal and climatic variability of the system. Thus, we utilized property-property plots as well as empirical relationships to compare pre- and post-storm water quality. Based on the variability of our empirical relationships, we estimate that to within 20%, the hurricane-induced vegetative destruction within this river basin has not changed the concentrations of DOC, POC, SPM, pH, or dissolved Fe. Nor has the quality of the DOC, as inferred from lignin-phenol analysis and the Fe-DOC relationship, been significantly changed either. This may be partly due to the slow degradation of woody materials that occurs only over a period of a few years, even in the sub-tropical climate of this region. Also, transport of DOC material from the land, through the soils, and into the river is not always instantaneous because DOC may stay in soils for a long time. Our work can be examined in the context of other research focused on hurricane effects on different time scales. For instance, shorter term hurricane influences, such as immediate flooding, can cause concurrent, short-lived water quality changes. Likewise, if increased hurricane activity (as might result from climate change) results in permanent landscape or ecosystem changes, then significant long-term water quality changes might be expected.

Developing a sustainable energy strategy for a water utility. Part I: A review of the UK legislative framework.

PubMed

Zakkour, P D; Gaterell, M R; Griffin, P; Gochin, R J; Lester, J N

2002-10-01

Increasing political effort to improve water quality across the UK and Europe has led to water and sewerage companies investing heavily in high-tech wastewater treatment plants capable of producing high quality effluents. Consequently, amounts of bought-in electricity used for wastewater treatment has and will continue to increase significantly over coming years, while greater provision of enhanced sewage treatment also produces greater volumes of sewage sludge requiring treatment and disposal. Over the same period, tougher controls on the quality of biosolids applied to agricultural land have also been introduced, while there has been an international attempt to reduce the use of fossil-fuel derived power sources because of concerns over global warming. The latter has brought about the introduction of financial instruments, such as the Climate Change Levy, to curb energy use, promote energy efficiency and encourage the development of renewable energy technologies. These factors are set to drive-up the costs of providing adequate sewage treatment services, while at the same time, a tough regulatory line taken to control profits on regional monopolies held by the UK water companies will significantly reduce their revenues over the period 2000-05. The result is that, financially, UK water and sewerage companies face their most challenging period since privatisation in 1989. This paper briefly outlines the current regulations relating to water quality and energy use that will affect water company operations over coming years.

Integrated Assessment of Artisanal and Small-Scale Gold Mining in Ghana-Part 2: Natural Sciences Review.

PubMed

Rajaee, Mozhgon; Obiri, Samuel; Green, Allyson; Long, Rachel; Cobbina, Samuel J; Nartey, Vincent; Buck, David; Antwi, Edward; Basu, Niladri

2015-07-31

This paper is one of three synthesis documents produced via an integrated assessment (IA) that aims to increase understanding of artisanal and small-scale gold mining (ASGM) in Ghana. Given the complexities surrounding ASGM, an integrated assessment (IA) framework was utilized to analyze socio-economic, health, and environmental data, and co-develop evidence-based responses with stakeholders. This paper focuses on the causes, status, trends, and consequences of ecological issues related to ASGM activity in Ghana. It reviews dozens of studies and thousands of samples to document evidence of heavy metals contamination in ecological media across Ghana. Soil and water mercury concentrations were generally lower than guideline values, but sediment mercury concentrations surpassed guideline values in 64% of samples. Arsenic, cadmium, and lead exceeded guideline values in 67%, 17%, and 24% of water samples, respectively. Other water quality parameters near ASGM sites show impairment, with some samples exceeding guidelines for acidity, turbidity, and nitrates. Additional ASGM-related stressors on environmental quality and ecosystem services include deforestation, land degradation, biodiversity loss, legacy contamination, and potential linkages to climate change. Though more research is needed to further elucidate the long-term impacts of ASGM on the environment, the plausible consequences of ecological damages should guide policies and actions to address the unique challenges posed by ASGM.

Development of Policies, Institutions and Procedures for Water Reuse

NASA Astrophysics Data System (ADS)

Demouche, L.; Pfiefer, J.; Hanson, A.; Skaggs, R.

2009-12-01

In the arid, water scarce region of New Mexico and West Texas there is growing interest in the potential for water reuse to extend existing supplies and mitigate drought shortage impacts. There are no new sources of water in New Mexico, except reclaimed water. Communities and individuals are uncertain about and have many unanswered questions about polices, institutions involved (agencies), legal and regulatory requirements, and procedures governing water reuse. Issues to be addressed by this project include: the legal ability to reuse water, ownership of water rights, downstream or third party impacts, regulatory and procedural requirements, water quality concerns, state and local agency involvement, and cost effectiveness of water reuse compared to alternative sources. Presently, there is very little implementation or directives in New Mexico policy that addresses reuse, reclamation, or recycled water. The only regulations pertaining to reuse is New Mexico Environmental Department currently allows the use of reclaimed domestic wastewater for irrigation of golf courses and green spaces, which is listed in the Policy for the Above Ground Use of Reclaimed Domestic Wastewater (NMED, 2003). This document identifies the various reclaimed quality classifications that are required for specific applications and the permits required for application. This document does not identify or address policy applications on the distribution, ownership, or trading of reclaimed water. Even though reclaimed water reuse projects are currently being implemented in many cities in the U.S., mainly for commercial and municipal irrigation (golf courses and green space), its potential has not yet been exploited. A policy analysis matrix (PAM) is being designed to identify and examine the policy framework and consequences of non-policy implementation for decision makers and interest groups and assist them in understanding the consequences of policy actions and project outcomes if no laws or regulations are created. The clarity of definitions is critical in policy analysis. Good economic analysis is fascinating for economist, frustrating for noneconomist, and relevant for everyone because it focuses on linkages within an economy—on why one group’s actions influence others in the system. The water reuse PAM is being used to identify the legality of water reuse, ownership of water rights, downstream or third party impacts, regulatory and procedural requirements, water quality concerns, state and local agency involvement, and cost effectiveness of water reuse compared to alternative sources. This project hopes to identify everyone involved in water reuse policy and provide them with clarity about the issues to help in evaluating and making sound policy decisions.

Threats and opportunities for freshwater conservation under future land use change scenarios in the United States.

PubMed

Martinuzzi, Sebastián; Januchowski-Hartley, Stephanie R; Pracheil, Brenda M; McIntyre, Peter B; Plantinga, Andrew J; Lewis, David J; Radeloff, Volker C

2014-01-01

Freshwater ecosystems provide vital resources for humans and support high levels of biodiversity, yet are severely threatened throughout the world. The expansion of human land uses, such as urban and crop cover, typically degrades water quality and reduces freshwater biodiversity, thereby jeopardizing both biodiversity and ecosystem services. Identifying and mitigating future threats to freshwater ecosystems requires forecasting where land use changes are most likely. Our goal was to evaluate the potential consequences of future land use on freshwater ecosystems in the coterminous United States by comparing alternative scenarios of land use change (2001-2051) with current patterns of freshwater biodiversity and water quality risk. Using an econometric model, each of our land use scenarios projected greater changes in watersheds of the eastern half of the country, where freshwater ecosystems already experience higher stress from human activities. Future urban expansion emerged as a major threat in regions with high freshwater biodiversity (e.g., the Southeast) or severe water quality problems (e.g., the Midwest). Our scenarios reflecting environmentally oriented policies had some positive effects. Subsidizing afforestation for carbon sequestration reduced crop cover and increased natural vegetation in areas that are currently stressed by low water quality, while discouraging urban sprawl diminished urban expansion in areas of high biodiversity. On the other hand, we found that increases in crop commodity prices could lead to increased agricultural threats in areas of high freshwater biodiversity. Our analyses illustrate the potential for policy changes and market factors to influence future land use trends in certain regions of the country, with important consequences for freshwater ecosystems. Successful conservation of aquatic biodiversity and ecosystem services in the United States into the future will require attending to the potential threats and opportunities arising from policies and market changes affecting land use. © 2013 John Wiley & Sons Ltd.

On the effect of operation of the hydropower plant on the water quality of Rapel reservoir, central Chile

NASA Astrophysics Data System (ADS)

Rossel, V.; De La Fuente, A.

2013-12-01

Eutrophication of lakes and reservoirs is a common problem in systems with high incoming loads of nutrients. The consequent algae bloom related to the eutrophication alters the water quality and generates an incompatibility with the tourist and recreational activities. This study is focused on Rapel reservoir: an old, dentritic and monomictic reservoir, located in central Chile (34°S, 71.6°W), that has experienced numerous algae bloom events in the past years produced by high loads of nutrients, sediments and metals. This reservoir was originally constructed in 1968 for hydropower generation without environmental restrictions on its operation. Rapel is part of Chile's Central Interconnected System (SIC), and is controlled by an independent system operator (ISO) that decides the optimal allocation of water by minimizing the SIC's operation cost. As a result of this framework, Rapel reservoir operates based on a hydropeaking scheme, thus producing energy few hours a day while zero outflows are observed the remaining hours, impacting on Rapel river located downstream the reservoir. However, previous research showed that this hydropeaking has important effects on the hydrodynamic of the reservoir as well. Particularly, it enhances vertical mixing nears the dam, and reduces horizontal dispersion. Furthermore, hydropeaking defines the outflows water temperature, and the temperature profile near the dam. As a consequence of this role of hydropeaking on the hydrodynamics and mixing of Rapel reservoir, it is expected to be a link between hydropeaking and water quality. The aim of the study is to evaluate the impact of the operation of hydropower plant on the water quality of Rapel reservoir, for which the reservoir system is modeled using the three dimensional hydrodynamic and water quality model ELCOM-CAEDYM. Field data to validate the results and to define boundary and initial conditions are available for the austral summer period of 2009-2010. Different scenarios of the hydropower plant outflows are obtained using an alternative of the ISO's economic optimization tool. A number of 20 simulations are conducted depending on the hydrological regime (dry, normal or wet) and on the presence or absence of an environmental flow. First of all, it was obtained that the hydropower plant operation depends on the hydrological regime, which produces changes in the storage volume, and on the environmental flow. Particularly, wet regime promotes high fluctuation on the storage, and the definition of an environmental flow reduces the outflow peaks.The numerical results show that there is a direct influence of hydropeaking on the water quality of Rapel reservoir, particularly in the area near the dam. This result is due to both changes in the storage volume, produced by different environmental flows and hydrological regime, and hydrodynamics and vertical mixing. The simulations also show that the introduction of an environmental flow downstream has an adverse impact on the internal quality of the reservoir, which is increased in the dry scenario. The study evidences the conflicting goals among environmental flow, SIC's operation costs and internal water quality of the reservoir.

Source to point of use drinking water changes and knowledge, attitude and practices in Katsina State, Northern Nigeria

NASA Astrophysics Data System (ADS)

Onabolu, B.; Jimoh, O. D.; Igboro, S. B.; Sridhar, M. K. C.; Onyilo, G.; Gege, A.; Ilya, R.

In many Sub-Saharan countries such as Nigeria, inadequate access to safe drinking water is a serious problem with 37% in the region and 58% of rural Nigeria using unimproved sources. The global challenge to measuring household water quality as a determinant of safety is further compounded in Nigeria by the possibility of deterioration from source to point of use. This is associated with the use of decentralised water supply systems in rural areas which are not fully reticulated to the household taps, creating a need for an integrated water quality monitoring system. As an initial step towards establishing the system in the north west and north central zones of Nigeria, The Katsina State Rural Water and Sanitation Agency, responsible for ensuring access to safe water and adequate sanitation to about 6 million people carried out a three pronged study with the support of UNICEF Nigeria. Part 1 was an assessment of the legislative and policy framework, institutional arrangements and capacity for drinking water quality monitoring through desk top reviews and Key Informant Interviews (KII) to ascertain the institutional capacity requirements for developing the water quality monitoring system. Part II was a water quality study in 700 households of 23 communities in four local government areas. The objectives were to assess the safety of drinking water, compare the safety at source and household level and assess the possible contributory role of end users’ Knowledge Attitudes and Practices. These were achieved through water analysis, household water quality tracking, KII and questionnaires. Part III was the production of a visual documentary as an advocacy tool to increase awareness of the policy makers of the linkages between source management, treatment and end user water quality. The results indicate that except for pH, conductivity and manganese, the improved water sources were safe at source. However there was a deterioration in water quality between source and point of use in 18%, 12.5%, 27% and 50% of hand pump fitted boreholes, motorised boreholes, hand dug wells and streams respectively. Although no statistical correlation could be drawn between water management practices and water quality deterioration, the survey of the study households gave an indication of the possible contributory role of their knowledge, attitudes and practices to water contamination after provision. Some of the potential water related sources of contamination were poor source protection and location, use of unimproved water source and poor knowledge and practice of household water treatment methods, poor hand washing practices in terms of percentage that wash hands and use soap. Consequently 34 WASH departments have been created at the local government level towards establishment of a community based monitoring system and piloting has begun in Kaita local government area.

Microbial and geochemical quality of shallow well water in high-density areas in Mzuzu City in Malawi

NASA Astrophysics Data System (ADS)

Msilimba, Golden; Wanda, Elijah M. M.

In Malawi, shallow wells constitute the most important water sources for domestic purposes. However, increasing human population coupled with poor sanitation and infrastructure is undermining the quality of shallow well water. An assessment of microbial and geochemical quality of shallow well water in high-density areas of Zolozolo, Ching’ambo and Chiputula in Mzuzu City, Northern Malawi, has been carried out. The study aimed at characterising domestic water sources, identifying possible sources of water contamination and determining levels of microbial and chemical contamination. Arc-view GIS was used to map the water sources. A questionnaire survey was carried out to elicit information on characteristics of drinking water sources. Water samples were collected from quasi-randomly selected shallow wells and analysed for microbial and chemical parameters using standard methods. HCA, performed using R-programme, was used to group sampled sites according to their bio-physicochemical characteristics. Compliance of the water with MBS/WHO water quality guidelines was determined. The WQI was computed to turn multifaceted data obtained from laboratory analyses into simple information that is comprehensible and useable by the public to assess overall quality of water at a specific water points. The GW-chart was used to show hydrogeochemical water types from each sampled site. Microbial analysis revealed that water from 96.3% of shallow wells recorded faecal coliforms ranging from 129 to 920 cfu per 100 ml which were significantly higher than the Malawi Standards and WHO thresholds. In general, shallow well water is of low mineralisation (EC range 80-500 μS cm-1), with hydrogeochemical facies dominated by Ca-HCO3, which evolves to Ca-Cl water type. The shallow well water registered a WQI range of 50.16-66.04%, with a medium WQ rating. This suggested that the water obtained from the shallow wells is unsuitable for direct human consumption. It was observed that 100% of the shallow wells were at risk of pollution from onsite sanitation because of their proximity to sanitary facilities. It was strongly recommended that onsite treatment interventions have to be mobilised and initiated to protect the households from further possible consequences of using the water.

A reconnaissance study of the effect of irrigated agriculture on water quality in the Ogallala Formation, Central High Plains Aquifer

USGS Publications Warehouse

McMahon, Peter B.

2000-01-01

In 1998, the U.S. Geological Survey's National Water-Quality Assessment (NAWQA) Program began a regional study of water quality in the High Plains aquifer. The High Plains aquifer underlies an area of about 174,000 square miles in parts of eight States. Because of its large size, the High Plains aquifer has been divided into three regions: the Southern High Plains, Central High Plains, and Northern High Plains. Although an assessment of water quality in each of the three regions is planned, the initial focus will be the Central High Plains aquifer. Anyone who has flown over the Central High Plains in the summer and has seen the large green circles associated with center pivot sprinklers knows that irrigated agriculture is a widespread land use. Pesticides and fertilizers applied on those irrigated fields will not degrade ground-water quality if they remain in or above the root zone. However, if those chemicals move downward through the unsaturated zone to the water table, they may degrade the quality of the ground water. Water is the principal agent for transporting chemicals from land surface to the water table, and in the semiarid Central High Plains, irrigation often represents the most abundant source of water during the growing season. One objective of NAWQA's High Plains Regional Ground-Water study is to evaluate the effect of irrigated agriculture on the quality of recently recharged water in the Ogallala Formation of the Central High Plains aquifer. The Ogallala Formation is the principal geologic unit in the Central High Plains aquifer, and it consists of poorly sorted clay, silt, sand, and gravel that generally is unconsolidated (Gutentag and others, 1984). Approximately 23 percent of the cropland overlying the Ogallala Formation is irrigated (U.S. Department of Agriculture, 1999). The NAWQA Program generally defines recently recharged ground water to be water recharged in the last 50 years. The water table in the Ogallala Formation is separated from overlying land-use practices by as much as 400 feet of unsaturated sediments. Consequently, one may hypothesize that recently recharged water is not present in the formation. The U.S. Geological Survey conducted a reconnaissance study in 1999 to establish (a) if recently recharged water was present in the Ogallala Formation underlying irrigated cropland and (b) if agricultural land-use practices affect water quality. Results from the reconnaissance study will be used to determine whether a full-scale land-use study is warranted.

SWEET CubeSat - Water detection and water quality monitoring for the 21st century

NASA Astrophysics Data System (ADS)

Antonini, Kelly; Langer, Martin; Farid, Ahmed; Walter, Ulrich

2017-11-01

Water scarcity and contamination of clean water have been identified as major challenges of the 21st century, in particular for developing countries. According to the International Water Management Institute, about 30% of the world's population does not have reliable access to clean water. Consequently, contaminated water contributes to the death of about 3 million people every year, mostly children. Access to potable water has been proven to boost education, equality and health, reduce hunger, as well as help the economy of the developing world. Currently used in-situ water monitoring techniques are sparse, and often difficult to execute. Space-based instruments will help to overcome these challenges by providing means for water level and water quality monitoring of medium-to-large sweet (fresh) water reservoirs. Data from hyperspectral imaging instruments on past and present governmental missions, such as Envisat and Aqua, has been used for this purpose. However, the high cost of large multi-purpose space vessels, and the lack of dedicated missions limits the continuous monitoring of inland and coastal water quality. The proposed CubeSat mission SWEET (Sweet Water Earth Education Technologies) will try to fill this gap. The SWEET concept is a joint effort between the Technical University of Munich, the German Space Operations Center and the African Steering Committee of the IAF. By using a novel Fabry-Perot interferometer-based hyperspectral imager, the mission will deliver critical data directly to national water resource centers in Africa with an unmatched cost per pixel ratio and high temporal resolution. Additionally, SWEET will incorporate education of students in CubeSat design and water management. Although the aim of the mission is to deliver local water quality and water level data to African countries, further coverage could be achieved with subsequent satellites. Finally, a constellation of SWEET-like CubeSats would extend the coverage to the whole planet, delivering daily data to ensure reliable access to clean water for millions of people worldwide.

Water-quality assessment of the Sacramento River basin, California : water quality of fixed sites, 1996-1998

USGS Publications Warehouse

Domagalski, Joseph L.; Dileanis, Peter D.

2000-01-01

Water-quality samples were collected from 12 sites in the Sacramento River Basin, Cali-fornia, from February 1996 through April 1998. Field measurements (dissolved oxygen, pH, specific conductance, alkalinity, and water tem-perature) were completed on all samples, and laboratory analyses were done for suspended sediments, nutrients, dissolved and particulate organic carbon, major ions, trace elements, and mercury species. Samples were collected at four types of locations on the Sacramento River?large tributaries to the Sacramento River, agricul-tural drainage canals, an urban stream, and a flood control channel. The samples were collected across a range of flow conditions representative of those sites during the timeframe of the study. The water samples from the Sacramento River indi-cate that specific conductance increases slightly downstream but that the water quality is indicative of dilute water. Water temperature of the Sacramento River increases below Shasta Lake during the spring and summer irrigation season owing to diversion of water out of the river and subsequent lower flow. All 12 sites had generally low concentrations of nutrients, but chlorophyll concentrations were not measured; therefore, the actual consequences of nutrient loading could not be adequately assessed. Concentrations of dis-solved organic carbon in samples from the Sacramento River and the major tributaries were generally low; the formation of trihalomethanes probably does not currently pose a problem when water from the Sacramento River and its major tributaries is chlorinated for drinking-water purposes. However, dissolved organic carbon concentrations were higher in the urban stream and in agricultural drainage canals, but were diluted upon mixing with the Sacramento River. The only trace element that currently poses a water-quality problem in the Sacramento River is mercury. A federal criterion for the protection of aquatic life was exceeded during this study, and floodwater concentrations of mercury were mostly higher than the criterion. Exceedances of water-quality standards happened most frequently during winter when suspended-sediment concen-trations also were elevated. Most mercury is found in association with suspended sediment. The greatest loading or transport of mercury out of the Sacramento River Basin to the San Francisco Bay occurs in the winter and principally follows storm events.

Environmental and ecological impacts of water supplement schemes in a heavily polluted estuary.

PubMed

Su, Qiong; Qin, Huapeng; Fu, Guangtao

2014-02-15

Water supplement has been used to improve water quality in a heavily polluted river with small base flow. However, its adverse impacts particularly on nearby sensitive ecosystems have not been fully investigated in previous studies. In this paper, using the Shenzhen River estuary in China as a case study, the impacts of two potential water supplement schemes (reclaimed water scheme and seawater scheme) on water quality improvement and salinity alteration of the estuary are studied. The influences of salinity alteration on the dominant mangrove species (Aegiceras corniculatum, Kandelia candel, and Avicennia marina) are further evaluated by comparing the alteration with the historical salinity data and the optimum salinity range for mangrove growth. The results obtained indicate that the targets of water quality improvement can be achieved by implementing the water supplement schemes with roughly the same flow rates. The salinity under the reclaimed water scheme lies in the range of historical salinity variation, and its average value is close to the optimum salinity for mangrove growth. Under the seawater scheme, however, the salinity in the estuary exceeds the range of historical salinity variation and approaches to the upper bound of the survival salinity of the mangrove species which have a relatively low salt tolerance (e.g. A. corniculatum). Therefore, the seawater scheme has negative ecological consequences, while the reclaimed water scheme has less ecological impact and is recommended in this study. Copyright © 2013 Elsevier B.V. All rights reserved.

Hurricane Katrina impact on water quality in the East Pearl River, Mississippi

NASA Astrophysics Data System (ADS)

Shiller, Alan M.; Shim, Moo-Joon; Guo, Laodong; Bianchi, Thomas S.; Smith, Richard W.; Duan, Shuiwang

2012-01-01

SummaryHurricanes and other intense storms have previously been reported to cause short-term changes in surface water quality. We examined the water quality of the East Pearl River in southern Mississippi both before and after Hurricane Katrina caused extensive damage to the watershed in 2005. Our post-storm sampling began two months after the hurricane, and thus we missed any immediate short-term consequences. However, sampling over the following two years allowed us to examine whether damage to the watershed resulted in significant longer-term effects on water quality. Interpretation of the time series data is complicated by the natural seasonal and climatic variability of the system. Thus, we utilized chemical property-property plots as well as semi-empirical relationships to compare pre- and post-storm water quality. Our analysis suggests that hurricane-induced vegetative destruction within this river basin has not substantially changed the concentrations of DOC, POC, SPM, pH, or dissolved Fe. However, lignin-phenol analysis of colloidal organic matter did show some significant changes in carbon-normalized concentration as well as in some degradation and source parameters. Nonetheless, even these changes were small and likely temporary. This lack of change may be partly due to the slow degradation of woody materials that occurs only over a period of a few years, even in the sub-tropical climate of this region. Also, transport of DOC material from the land, through the soils, and into the river is not always instantaneous because DOC may stay in soils for a long time. Our work can be examined in the context of other research focused on hurricane effects on different time scales. For instance, shorter term hurricane influences, such as immediate flooding, can cause concurrent, short-lived water quality changes. Likewise, if increased hurricane activity (as might result from climate change) results in permanent landscape or ecosystem changes, then significant long-term water quality changes might be expected.

Addressing Externalities From Swine Production to Reduce Public Health and Environmental Impacts

PubMed Central

Osterberg, David; Wallinga, David

2004-01-01

Animal agriculture in the United States for the most part has industrialized, with negative consequences for air and water quality and antibiotic use. We consider health and environmental impacts of current US swine production and give an overview of current federal, state, and local strategies being used to address them. PMID:15451736

Oceanography for Divers: Waves, Tides, and Currents. Diver Education Series.

ERIC Educational Resources Information Center

Somers, Lee H.

To dive safely, it is suggested that the diver have a working knowledge of waves, tides, currents, and water quality. Lack of understanding and respect for ocean currents and surf can be of serious consequence to the diver. This paper on the diving environment is designed to provide the diver with a general understanding of the physical…

Overview of best management practices related to forest roads: The southern states

Treesearch

Johnny M. Grace

2002-01-01

Forest roads are vital in the implementation of most all forest management activities. However, the potential of forest roads to have accelerated erosion losses and degrade water quality through stream sedimentation has long been recognized throughout the U.S. Forest roads have the potential to cause serious environmental impacts (possibly consequences) without...

A global index for mapping the exposure of water resources to wildfire

Treesearch

Francois-Nicolas Robinne; Carol Miller; Marc-Andre Parisien; Monica B. Emelko; Kevin D. Bladon; Uldis Silins; Mike Flannigan

2016-01-01

Wildfires are keystone components of natural disturbance regimes that maintain ecosystem structure and functions, such as the hydrological cycle, in many parts of the world. Consequently, critical surface freshwater resources can be exposed to post-fire effects disrupting their quantity, quality and regularity. Although well studied at the local scale, the potential...

Hillslope erosion rates in the oak savannas of the southwestern borderlands region

Treesearch

Aaron T. Kauffman; Cody L. Stropki; Peter F. Ffolliott; Gerald J. Gottfried; Daniel G. Neary

2007-01-01

Hillslope soil erosion on watershed landscapes can lower the productivity of upland sites and adversely impact water quality and downstream (off-site) areas. It is not surprising, therefore, that excessive soil erosion and the consequent sedimentation can represent significant costs to the land and people that are affected. The first known estimates of hillslope soil...

Hawaii Energy Resource Overviews. Volume 4. Impact of geothermal resource development in Hawaii (including air and water quality)

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

Siegel, S.M.; Siegel, B.Z.

1980-06-01

The environmental consequences of natural processes in a volcanic-fumerolic region and of geothermal resource development are presented. These include acute ecological effects, toxic gas emissions during non-eruptive periods, the HGP-A geothermal well as a site-specific model, and the geothermal resources potential of Hawaii. (MHR)

Consequences of varied soil hydraulic and meteorological complexity on unsaturated zone time lag estimates.

PubMed

Vero, S E; Ibrahim, T G; Creamer, R E; Grant, J; Healy, M G; Henry, T; Kramers, G; Richards, K G; Fenton, O

2014-12-01

The true efficacy of a programme of agricultural mitigation measures within a catchment to improve water quality can be determined only after a certain hydrologic time lag period (subsequent to implementation) has elapsed. As the biophysical response to policy is not synchronous, accurate estimates of total time lag (unsaturated and saturated) become critical to manage the expectations of policy makers. The estimation of the vertical unsaturated zone component of time lag is vital as it indicates early trends (initial breakthrough), bulk (centre of mass) and total (Exit) travel times. Typically, estimation of time lag through the unsaturated zone is poor, due to the lack of site specific soil physical data, or by assuming saturated conditions. Numerical models (e.g. Hydrus 1D) enable estimates of time lag with varied levels of input data. The current study examines the consequences of varied soil hydraulic and meteorological complexity on unsaturated zone time lag estimates using simulated and actual soil profiles. Results indicated that: greater temporal resolution (from daily to hourly) of meteorological data was more critical as the saturated hydraulic conductivity of the soil decreased; high clay content soils failed to converge reflecting prevalence of lateral component as a contaminant pathway; elucidation of soil hydraulic properties was influenced by the complexity of soil physical data employed (textural menu, ROSETTA, full and partial soil water characteristic curves), which consequently affected time lag ranges; as the importance of the unsaturated zone increases with respect to total travel times the requirements for high complexity/resolution input data become greater. The methodology presented herein demonstrates that decisions made regarding input data and landscape position will have consequences for the estimated range of vertical travel times. Insufficiencies or inaccuracies regarding such input data can therefore mislead policy makers regarding the achievability of water quality targets. Copyright © 2014 Elsevier B.V. All rights reserved.

Results of a modeling workshop concerning economic and environmental trends and concomitant resource management issues in the Mobile Bay area

USGS Publications Warehouse

Hamilton, David B.; Andrews, Austin K.; Auble, Gregor T.; Ellison, Richard A.; Johnson, Richard A.; Roelle, James E.; Staley, Michael J.

1982-01-01

During the past decade, the southern regions of the U.S. have experienced rapid change which is expected to continue into the foreseeable future. Growth in population, industry, and resource development has been attributed to a variety of advantages such as an abundant and inexpensive labor force, a mild climate, and the availability of energy, water, land, and other natural resources. While this growth has many benefits for the region, it also creates the potential for increased air, water, and solid waste pollution, and modification of natural habitats. A workshop was convened to consider the Mobile Bay area as a site-specific case of growth and its environmental consequences in the southern region. The objectives of the modeling workshop were to: (1) identify major factors of economic development as they relate to growth in the area over the immediate and longer term; (2) identify major environmental and resource management issues associated with this expected growth; and (3) identify and characterize the complex interrelationships among economic and environmental factors. This report summarizes the activities and results of a modeling workshop concerning economic growth and concomitant resource management issues in the Mobile Bay area. The workshop was organized around construction of a simulation model representing the relationships between a series of actions and indicators identified by participants. The workshop model had five major components. An Industry Submodel generated scenarios of growth in several industrial and transportation sectors. A Human Population/Economy Submodel calculated human population and economic variables in response to employment opportunities. A Land Use/Air Quality Submodel tabulated changes in land use, shoreline use, and air quality. A Water Submodel calculated indicators of water quality and quantity for fresh surface water, ground water, and Mobile Bay based on discharge information provided by the Industry and Human Population/Economy Submodels. Finally, a Fish Submodel calculated indicators of habitat quality for finfish and shellfish, utilizing information on water quality and wetlands acreage. The workshop was successful in identifying many of the critical interrelations between components of the Mobile area system. Not all of those interactions, such as the feedback of air quality as a limitation on development, could be incorporated into the workshop model because of the model's broad spatial scale and because of uncertainties or data gaps. Thus, the value of the modeling workshop was in the areas outlines below, rather than in the predictive power of the initial model developed at the workshop. First, participants developed a holistic perspective on the interactions which will determine future economic and environmental trends within the Mobile Bay area. Potential environmental consequences and limitations to grown identified at the workshop included: shoreline and water access; water quality of Mobile Bay; finfish and shellfish habitat quality with respect to dissolved oxygen and coliforms; air quality; and acreage of critical wetland habitat. Second, the model's requirements for specific, quantitative information stimulated supporting analyses, such as economic input-output calculations, which provide additional insight into the Mobile Bay area system. Third, the perspective of the Mobile area as an interacting system was developed in an open, cooperative forum which my provide a foundation for conflict resolution based on common understanding. Finally, the identification of model limitations and uncertainties should be useful in guiding the efficient allocation of future research effort.

Calculation of intercepted runoff depth based on stormwater quality and environmental capacity of receiving waters for initial stormwater pollution management.

PubMed

Peng, Hai-Qin; Liu, Yan; Gao, Xue-Long; Wang, Hong-Wu; Chen, Yi; Cai, Hui-Yi

2017-11-01

While point source pollutions have gradually been controlled in recent years, the non-point source pollution problem has become increasingly prominent. The receiving waters are frequently polluted by the initial stormwater from the separate stormwater system and the wastewater from sewage pipes through stormwater pipes. Consequently, calculating the intercepted runoff depth has become a problem that must be resolved immediately for initial stormwater pollution management. The accurate calculation of intercepted runoff depth provides a solid foundation for selecting the appropriate size of intercepting facilities in drainage and interception projects. This study establishes a separate stormwater system for the Yishan Building watershed of Fuzhou City using the InfoWorks Integrated Catchment Management (InfoWorks ICM), which can predict the stormwater flow velocity and the flow of discharge outlet after each rainfall. The intercepted runoff depth is calculated from the stormwater quality and environmental capacity of the receiving waters. The average intercepted runoff depth from six rainfall events is calculated as 4.1 mm based on stormwater quality. The average intercepted runoff depth from six rainfall events is calculated as 4.4 mm based on the environmental capacity of the receiving waters. The intercepted runoff depth differs when calculated from various aspects. The selection of the intercepted runoff depth depends on the goal of water quality control, the self-purification capacity of the water bodies, and other factors of the region.

On the complex non-linear interaction between bacteria and redox dynamics in sediments and its effects on water quality

NASA Astrophysics Data System (ADS)

Sanchez-Vila, X.; Rubol, S.; Fernandez-Garcia, D.

2011-12-01

Despite the fact that the prognoses on the availability of resources related to different climate scenarios have been already formulated, the complex hydrological and biogeochemical reactions taking place in different compartments in natural environmental media are poorly understood, especially regarding the interactions between water bodies, and the reactions taking place at soil-water interfaces. Amongst them, the inter-relationship between hydrology, chemistry and biology has important implications in natural (rivers, lakes) and man-made water facilities (lagoons, artificial recharge pounds, reservoirs, slow infiltration systems, etc). The consequences involve environment, economic, social and health-risk aspects. At the current stage, only limited explanations are available to understand the implications of these relationships on ecosystem services, water quality and water quantity. Therefore, there is an urgent need to seek a full understanding of these physical-biogeochemical processes in water-bodies, sediments and biota and its implications in ecological and health risk. We present a soil column experiment and a mathematical model which aim to study the mutual interplay between water and bacteria activity in porous media, the corresponding dynamics and the feedback on nutrient cycling by using a multidisciplinary approach.

Notes on the husbandry and long-term transportation of Bull ray (Pteromylaeus bovinus) and Dolphinfish (Coryphaena hippurus and Coryphaena equiselis).

PubMed

Rodrigues, Nuno; Correia, João; Pinho, Rúben; Graça, José; Rodrigues, Filipe; Hirofumi, Morikawa

2013-03-01

Bull rays (Pteromylaeus bovinus) and Dolphinfish (Coryphaena hippurus and Coryphaena equiselis) were collected in Olhão (south of Portugal). These animals hosted multiple parasites, namely Caligus spp., and underwent a variety of treatments to remove them. Of all treatments tested, hydrogen peroxide showed the best results, although only concentrations above 100 ppm were effective in parasite removal. These high concentrations, however, proved to be highly toxic for the fish and led to the loss of some animals, especially those which had been handled before treatment. A total of 14 Bull rays were transported to Bolougne-Sur-Mer (France) by road and some animals were lost, which was attributed to excessive time in transit (>45 hr). In another transport, three Bull rays and 10 Dolphinfishes were moved to Stralsund (Germany) by road and air. The mechanical wounds suffered by one of the Bull rays during transport led to its death and, consequently, a deterioration of water quality in the tank containing two other conspecifics. This deterioration of water quality resulted in problems for the other two Bull rays, and one perished approximately 48 hr after arrival. The authors concluded that Dolphinfish can be transported with a low bioload for at least 27 hr, and Bull rays should not undergo transports longer than 35 hr. Special attention must be taken to injured animals, since this can lead to a decrease in water quality and consequently affect other animals in the same transport tank. © 2012 Wiley Periodicals, Inc.

Innovative biological approaches for monitoring and improving water quality

PubMed Central

Aracic, Sanja; Manna, Sam; Petrovski, Steve; Wiltshire, Jennifer L.; Mann, Gülay; Franks, Ashley E.

2015-01-01

Water quality is largely influenced by the abundance and diversity of indigenous microbes present within an aquatic environment. Physical, chemical and biological contaminants from anthropogenic activities can accumulate in aquatic systems causing detrimental ecological consequences. Approaches exploiting microbial processes are now being utilized for the detection, and removal or reduction of contaminants. Contaminants can be identified and quantified in situ using microbial whole-cell biosensors, negating the need for water samples to be tested off-site. Similarly, the innate biodegradative processes can be enhanced through manipulation of the composition and/or function of the indigenous microbial communities present within the contaminated environments. Biological contaminants, such as detrimental/pathogenic bacteria, can be specifically targeted and reduced in number using bacteriophages. This mini-review discusses the potential application of whole-cell microbial biosensors for the detection of contaminants, the exploitation of microbial biodegradative processes for environmental restoration and the manipulation of microbial communities using phages. PMID:26322034

A structural approach to understanding the interactions between colour, water-holding capacity and tenderness.

PubMed

Hughes, J M; Oiseth, S K; Purslow, P P; Warner, R D

2014-11-01

The colour, water-holding capacity (WHC) and tenderness of meat are primary determinants of visual and sensory appeal. Although there are many factors which influence these quality traits, the end-results of their influence is often through key changes to the structure of muscle proteins and their spatial arrangement. Water acts as a plasticiser of muscle proteins and water is lost from the myofibrillar lattice structure as a result of protein denaturation and consequent reductions in the muscle fibre volume with increasing cooking temperature. Changes in the myofilament lattice arrangement also impact the light scattering properties and the perceived paleness of the meat. Causes of variation in the quality traits of raw meat do not generally correspond to variations in cooked meat and the differences observed between the raw muscle and cooked or further processed meat are discussed. The review will also identify the gaps in our knowledge and where further investigation would beneficial. Copyright © 2014 Elsevier Ltd. All rights reserved.

Managing the effects of multiple stressors on aquatic ecosystems under water scarcity. The GLOBAQUA project.

PubMed

Navarro-Ortega, Alícia; Acuña, Vicenç; Bellin, Alberto; Burek, Peter; Cassiani, Giorgio; Choukr-Allah, Redouane; Dolédec, Sylvain; Elosegi, Arturo; Ferrari, Federico; Ginebreda, Antoni; Grathwohl, Peter; Jones, Colin; Rault, Philippe Ker; Kok, Kasper; Koundouri, Phoebe; Ludwig, Ralf Peter; Merz, Ralf; Milacic, Radmila; Muñoz, Isabel; Nikulin, Grigory; Paniconi, Claudio; Paunović, Momir; Petrovic, Mira; Sabater, Laia; Sabaterb, Sergi; Skoulikidis, Nikolaos Th; Slob, Adriaan; Teutsch, Georg; Voulvoulis, Nikolaos; Barceló, Damià

2015-01-15

Water scarcity is a serious environmental problem in many European regions, and will likely increase in the near future as a consequence of increased abstraction and climate change. Water scarcity exacerbates the effects of multiple stressors, and thus results in decreased water quality. It impacts river ecosystems, threatens the services they provide, and it will force managers and policy-makers to change their current practices. The EU-FP7 project GLOBAQUA aims at identifying the prevalence, interaction and linkages between stressors, and to assess their effects on the chemical and ecological status of freshwater ecosystems in order to improve water management practice and policies. GLOBAQUA assembles a multidisciplinary team of 21 European plus 2 non-European scientific institutions, as well as water authorities and river basin managers. The project includes experts in hydrology, chemistry, biology, geomorphology, modelling, socio-economics, governance science, knowledge brokerage, and policy advocacy. GLOBAQUA studies six river basins (Ebro, Adige, Sava, Evrotas, Anglian and Souss Massa) affected by water scarcity, and aims to answer the following questions: how does water scarcity interact with other existing stressors in the study river basins? How will these interactions change according to the different scenarios of future global change? Which will be the foreseeable consequences for river ecosystems? How will these in turn affect the services the ecosystems provide? How should management and policies be adapted to minimise the ecological, economic and societal consequences? These questions will be approached by combining data-mining, field- and laboratory-based research, and modelling. Here, we outline the general structure of the project and the activities to be conducted within the fourteen work-packages of GLOBAQUA. Copyright © 2014. Published by Elsevier B.V.

Managing the effects of multiple stressors on aquatic ecosystems under water scarcity. The GLOBAQUA project

PubMed Central

Navarro-Ortega, Alícia; Acuña, Vicenç; Bellin, Alberto; Burek, Peter; Cassiani, Giorgio; Choukr-Allah, Redouane; Dolédec, Sylvain; Elosegi, Arturo; Ferrari, Federico; Ginebreda, Antoni; Grathwohl, Peter; Jones, Colin; Rault, Philippe Ker; Kok, Kasper; Koundouri, Phoebe; Ludwig, Ralf Peter; Merz, Ralf; Milacic, Radmila; Muñoz, Isabel; Nikulin, Grigory; Paniconi, Claudio; Paunović, Momir; Petrovic, Mira; Sabater, Laia; Sabaterb, Sergi; Skoulikidis, Nikolaos Th.; Slob, Adriaan; Teutsch, Georg; Voulvoulis, Nikolaos; Barceló, Damià

2015-01-01

Water scarcity is a serious environmental problem in many European regions, and will likely increase in the near future as a consequence of increased abstraction and climate change. Water scarcity exacerbates the effects of multiple stressors, and thus results in decreased water quality. It impacts river ecosystems, threatens the services they provide, and it will force managers and policy-makers to change their current practices. The EU-FP7 project GLOBAQUA aims at identifying the prevalence, interaction and linkages between stressors, and to assess their effects on the chemical and ecological status of freshwater ecosystems in order to improve water management practice and policies. GLOBAQUA assembles a multidisciplinary team of 21 European plus 2 non-European scientific institutions, as well as water authorities and river basin managers. The project includes experts in hydrology, chemistry, biology, geomorphology, modelling, socio-economics, governance science, knowledge brokerage, and policy advocacy. GLOBAQUA studies six river basins (Ebro, Adige, Sava, Evrotas, Anglian and Souss Massa) affected by water scarcity, and aims to answer the following questions: how does water scarcity interact with other existing stressors in the study river basins? How will these interactions change according to the different scenarios of future global change? Which will be the foreseeable consequences for river ecosystems? How will these in turn affect the services the ecosystems provide? How should management and policies be adapted to minimise the ecological, economic and societal consequences? These questions will be approached by combining data-mining, field- and laboratory-based research, and modelling. Here, we outline the general structure of the project and the activities to be conducted within the fourteen work-packages of GLOBAQUA. PMID:25005236

Geohydrology of Crow Creek and Lower Brule Indian Reservations, South Dakota

USGS Publications Warehouse

Howells, Lewis W.

1974-01-01

Effective improvement of economic and social conditions of Indians living on Crow Creek and Lower Brule Reservations has been hampered by lack of adequate and reliable information about the quantity and quality of water supplies available for development.  Compounding the problem, and making especially pressing the need for discovery and development of new water supplies, is the recent filling of Fort Randall and Big Bend Reservoirs on the Missouri River, and the consequent relocation of may residents.  Much of the best land and known water supplies are inundated beneath the reservoirs.  This report summarized the results of a water-resources study made at the request of the U.S. Bureau of Indian Affairs.

The role of pesticide fate modelling in a prevention-led approach to potable water quality management

NASA Astrophysics Data System (ADS)

Dolan, Tom; Pullan, Stephanie; Whelan, Mick; Parsons, David

2013-04-01

Diffuse inputs from agriculture are commonly the main source of pesticide contamination in surface water and may have implications for the quality of treated drinking water. After privatisation in 1991, UK water companies primarily focused on the provision of sufficient water treatment to reduce the risk of non-compliance with the European Drinking Water Directive (DWD), under which all pesticide concentrations must be below 0.1µg/l and UK Water Supply Regulations for the potable water they supply. Since 2000, Article 7 of the Water Framework Directive (WFD) has begun to drive a prevention-led approach to compliance with the DWD. As a consequence water companies are now more interested in the quality of 'raw' (untreated) water at the point of abstraction. Modelling (based upon best available estimates of cropping, pesticide use, weather conditions, pesticide characteristics, and catchment characteristics) and monitoring of raw water quality can both help to determine the compliance risks associated with the quality of this 'raw' water resource. This knowledge allows water companies to prioritise active substances for action in their catchments, and is currently used in many cases to support the design of monitoring programmes for pesticide active substances. Additional value can be provided if models are able to help to identify the type and scale of catchment management interventions required to achieve DWD compliance for pesticide active substances through pollution prevention at source or along transport pathways. These questions were explored using a simple catchment-scale pesticide fate and transport model. The model employs a daily time-step and is semi-lumped with calculations performed for soil type and crop combinations, weighted by their proportions within the catchment. Soil properties are derived from the national soil database and the model can, therefore, be applied to any catchment in England and Wales. Various realistic catchment management intervention scenarios were explored (including changes to land use and pesticide usage) with the aim of providing a useful input to the debate between water companies, their regulators and pesticide users over the scale of catchment management required to support both DWD and WFD Article 7 compliance.

Spatially explicit integrated modeling and economic valuation of climate driven land use change and its indirect effects.

PubMed

Bateman, Ian; Agarwala, Matthew; Binner, Amy; Coombes, Emma; Day, Brett; Ferrini, Silvia; Fezzi, Carlo; Hutchins, Michael; Lovett, Andrew; Posen, Paulette

2016-10-01

We present an integrated model of the direct consequences of climate change on land use, and the indirect effects of induced land use change upon the natural environment. The model predicts climate-driven shifts in the profitability of alternative uses of agricultural land. Both the direct impact of climate change and the induced shift in land use patterns will cause secondary effects on the water environment, for which agriculture is the major source of diffuse pollution. We model the impact of changes in such pollution on riverine ecosystems showing that these will be spatially heterogeneous. Moreover, we consider further knock-on effects upon the recreational benefits derived from water environments, which we assess using revealed preference methods. This analysis permits a multi-layered examination of the economic consequences of climate change, assessing the sequence of impacts from climate change through farm gross margins, land use, water quality and recreation, both at the individual and catchment scale. Copyright © 2016 Elsevier Ltd. All rights reserved.

Water quality modelling of an impacted semi-arid catchment using flow data from the WEAP model

NASA Astrophysics Data System (ADS)

Slaughter, Andrew R.; Mantel, Sukhmani K.

2018-04-01

The continuous decline in water quality in many regions is forcing a shift from quantity-based water resources management to a greater emphasis on water quality management. Water quality models can act as invaluable tools as they facilitate a conceptual understanding of processes affecting water quality and can be used to investigate the water quality consequences of management scenarios. In South Africa, the Water Quality Systems Assessment Model (WQSAM) was developed as a management-focussed water quality model that is relatively simple to be able to utilise the small amount of available observed data. Importantly, WQSAM explicitly links to systems (yield) models routinely used in water resources management in South Africa by using their flow output to drive water quality simulations. Although WQSAM has been shown to be able to represent the variability of water quality in South African rivers, its focus on management from a South African perspective limits its use to within southern African regions for which specific systems model setups exist. Facilitating the use of WQSAM within catchments outside of southern Africa and within catchments for which these systems model setups to not exist would require WQSAM to be able to link to a simple-to-use and internationally-applied systems model. One such systems model is the Water Evaluation and Planning (WEAP) model, which incorporates a rainfall-runoff component (natural hydrology), and reservoir storage, return flows and abstractions (systems modelling), but within which water quality modelling facilities are rudimentary. The aims of the current study were therefore to: (1) adapt the WQSAM model to be able to use as input the flow outputs of the WEAP model and; (2) provide an initial assessment of how successful this linkage was by application of the WEAP and WQSAM models to the Buffalo River for historical conditions; a small, semi-arid and impacted catchment in the Eastern Cape of South Africa. The simulations of the two models were compared to the available observed data, with the initial focus within WQSAM on a simulation of instream total dissolved solids (TDS) and nutrient concentrations. The WEAP model was able to adequately simulate flow in the Buffalo River catchment, with consideration of human inputs and outputs. WQSAM was adapted to successfully take as input the flow output of the WEAP model, and the simulations of nutrients by WQSAM provided a good representation of the variability of observed nutrient concentrations in the catchment. This study showed that the WQSAM model is able to accept flow inputs from the WEAP model, and that this approach is able to provide satisfactory estimates of both flow and water quality for a small, semi-arid and impacted catchment. It is hoped that this research will encourage the application of WQSAM to an increased number of catchments within southern Africa and beyond.

Accounting for and predicting the influence of spatial autocorrelation in water quality modeling

NASA Astrophysics Data System (ADS)

Miralha, L.; Kim, D.

2017-12-01

Although many studies have attempted to investigate the spatial trends of water quality, more attention is yet to be paid to the consequences of considering and ignoring the spatial autocorrelation (SAC) that exists in water quality parameters. Several studies have mentioned the importance of accounting for SAC in water quality modeling, as well as the differences in outcomes between models that account for and ignore SAC. However, the capacity to predict the magnitude of such differences is still ambiguous. In this study, we hypothesized that SAC inherently possessed by a response variable (i.e., water quality parameter) influences the outcomes of spatial modeling. We evaluated whether the level of inherent SAC is associated with changes in R-Squared, Akaike Information Criterion (AIC), and residual SAC (rSAC), after accounting for SAC during modeling procedure. The main objective was to analyze if water quality parameters with higher Moran's I values (inherent SAC measure) undergo a greater increase in R² and a greater reduction in both AIC and rSAC. We compared a non-spatial model (OLS) to two spatial regression approaches (spatial lag and error models). Predictor variables were the principal components of topographic (elevation and slope), land cover, and hydrological soil group variables. We acquired these data from federal online sources (e.g. USGS). Ten watersheds were selected, each in a different state of the USA. Results revealed that water quality parameters with higher inherent SAC showed substantial increase in R² and decrease in rSAC after performing spatial regressions. However, AIC values did not show significant changes. Overall, the higher the level of inherent SAC in water quality variables, the greater improvement of model performance. This indicates a linear and direct relationship between the spatial model outcomes (R² and rSAC) and the degree of SAC in each water quality variable. Therefore, our study suggests that the inherent level of SAC in response variables can predict improvements in models even before performing spatial regression approaches. We also recognize the constraints of this research and suggest that further studies focus on better ways of defining spatial neighborhoods, considering the differences among stations set in tributaries near to each other and in upstream areas.

Impact of river basin management on coastal water quality and ecosystem services: A southern Baltic estuary

NASA Astrophysics Data System (ADS)

Schernewski, Gerald; Hürdler, Jens; Neumann, Thomas; Stybel, Nardine; Venohr, Markus

2010-05-01

Eutrophication management is still a major challenge in the Baltic Sea region. Estuaries or coastal waters linked to large rivers cannot be managed independently. Nutrient loads into these coastal ecosystems depend on processes, utilisation, structure and management in the river basin. In practise this means that we need a large scale approach and integrated models and tools to analyse, assess and evaluate the effects of nutrient loads on coastal water quality as well as the efficiency of river basin management measures on surface waters and especially lagoons and estuaries. The Odra river basin, the Szczecin Lagoon and its coastal waters cover an area of about 150,000 km² and are an eutrophication hot-spot in the Baltic region. To be able to carry out large scale, spatially integrative analyses, we linked the river basin nutrient flux model MONERIS to the coastal 3D-hydrodynamic and ecosystem model ERGOM. Objectives were a) to analyse the eutrophication history in the river basin and the resulting functional changes in the coastal waters between early 1960's and today and b) to analyse the effects of an optimal nitrogen and phosphorus management scenario in the Oder/Odra river basin on coastal water quality. The models show that an optimal river basin management with reduced nutrient loads (e.g. N-load reduction of 35 %) would have positive effects on coastal water quality and algae biomass. The availability of nutrients, N/P ratios and processes like denitrification and nitrogen-fixation would show spatial and temporal changes. It would have positive consequences for ecosystems functions, like the nutrient retention capacity, as well. However, this optimal scenario is by far not sufficient to ensure a good coastal water quality according to the European Water Framework Directive. A "good" water quality in the river will not be sufficient to ensure a "good" water quality in the coastal waters. Further, nitrogen load reductions bear the risk of increased potentially toxic, blue-green algae blooms. The presentation will summarize recent results (Behrendt et al. 2009, Schernewski et al. 2009, Schernewski et al. in press, Schernewski et al. submitted) and give an overview how Climate Change and socio-economic transformation processes in the river basin will effect coastal water quality during the next decades. The opportunities and threats of a changing lagoon ecosystem for tourism and fisheries, the major economic activities, will be shown.

Sources and preparation of data for assessing trends in concentrations of pesticides in streams of the United States, 1992–2010

USGS Publications Warehouse

Martin, Jeffrey D.; Eberle, Michael; Nakagaki, Naomi

2011-01-01

This report updates a previously published water-quality dataset of 44 commonly used pesticides and 8 pesticide degradates suitable for a national assessment of trends in pesticide concentrations in streams of the United States. Water-quality samples collected from January 1992 through September 2010 at stream-water sites of the U.S. Geological Survey (USGS) National Water-Quality Assessment (NAWQA) Program and the National Stream Quality Accounting Network (NASQAN) were compiled, reviewed, selected, and prepared for trend analysis. The principal steps in data review for trend analysis were to (1) identify analytical schedule, (2) verify sample-level coding, (3) exclude inappropriate samples or results, (4) review pesticide detections per sample, (5) review high pesticide concentrations, and (6) review the spatial and temporal extent of NAWQA pesticide data and selection of analytical methods for trend analysis. The principal steps in data preparation for trend analysis were to (1) select stream-water sites for trend analysis, (2) round concentrations to a consistent level of precision for the concentration range, (3) identify routine reporting levels used to report nondetections unaffected by matrix interference, (4) reassign the concentration value for routine nondetections to the maximum value of the long-term method detection level (maxLT-MDL), (5) adjust concentrations to compensate for temporal changes in bias of recovery of the gas chromatography/mass spectrometry (GCMS) analytical method, and (6) identify samples considered inappropriate for trend analysis. Samples analyzed at the USGS National Water Quality Laboratory (NWQL) by the GCMS analytical method were the most extensive in time and space and, consequently, were selected for trend analysis. Stream-water sites with 3 or more water years of data with six or more samples per year were selected for pesticide trend analysis. The selection criteria described in the report produced a dataset of 21,988 pesticide samples at 212 stream-water sites. Only 21,144 pesticide samples, however, are considered appropriate for trend analysis.

Spatiotemporal classification of environmental monitoring data in the Yeongsan River basin, Korea, using self-organizing maps.

PubMed

Jin, Y-H; Kawamura, A; Park, S-C; Nakagawa, N; Amaguchi, H; Olsson, J

2011-10-01

Environmental monitoring data for planning, implementing and evaluating the Total Maximum Daily Loads (TMDL) management system have been measured at about 8-day intervals in a number of rivers in Korea since 2004. In the present study, water quality parameters such as Suspended Solids (SS), Biochemical Oxygen Demand (BOD), Dissolved Oxygen (DO), Total Nitrogen (TN), and Total Phosphorus (TP) and the corresponding runoff were collected from six stations in the Yeongsan River basin for six years and transformed into monthly mean values. With the primary objective to understand spatiotemporal characteristics of the data, a methodologically systematic application of a Self-Organizing Map (SOM) was made. The SOM application classified the environmental monitoring data into nine clusters showing exclusively distinguishable patterns. Data frequency at each station on a monthly basis identified the spatiotemporal distribution for the first time in the study area. Consequently, the SOM application provided useful information that the sub-basin containing a metropolitan city is associated with deteriorating water quality and should be monitored and managed carefully during spring and summer for water quality improvement in the river basin.

Integrated Assessment of Artisanal and Small-Scale Gold Mining in Ghana—Part 2: Natural Sciences Review

PubMed Central

Rajaee, Mozhgon; Obiri, Samuel; Green, Allyson; Long, Rachel; Cobbina, Samuel J.; Nartey, Vincent; Buck, David; Antwi, Edward; Basu, Niladri

2015-01-01

This paper is one of three synthesis documents produced via an integrated assessment (IA) that aims to increase understanding of artisanal and small-scale gold mining (ASGM) in Ghana. Given the complexities surrounding ASGM, an integrated assessment (IA) framework was utilized to analyze socio-economic, health, and environmental data, and co-develop evidence-based responses with stakeholders. This paper focuses on the causes, status, trends, and consequences of ecological issues related to ASGM activity in Ghana. It reviews dozens of studies and thousands of samples to document evidence of heavy metals contamination in ecological media across Ghana. Soil and water mercury concentrations were generally lower than guideline values, but sediment mercury concentrations surpassed guideline values in 64% of samples. Arsenic, cadmium, and lead exceeded guideline values in 67%, 17%, and 24% of water samples, respectively. Other water quality parameters near ASGM sites show impairment, with some samples exceeding guidelines for acidity, turbidity, and nitrates. Additional ASGM-related stressors on environmental quality and ecosystem services include deforestation, land degradation, biodiversity loss, legacy contamination, and potential linkages to climate change. Though more research is needed to further elucidate the long-term impacts of ASGM on the environment, the plausible consequences of ecological damages should guide policies and actions to address the unique challenges posed by ASGM. PMID:26264012

Value of information analysis for groundwater quality monitoring network design Case study: Eocene Aquifer, Palestine

NASA Astrophysics Data System (ADS)

Khader, A.; McKee, M.

2010-12-01

Value of information (VOI) analysis evaluates the benefit of collecting additional information to reduce or eliminate uncertainty in a specific decision-making context. It makes explicit any expected potential losses from errors in decision making due to uncertainty and identifies the “best” information collection strategy as one that leads to the greatest expected net benefit to the decision-maker. This study investigates the willingness to pay for groundwater quality monitoring in the Eocene Aquifer, Palestine, which is an unconfined aquifer located in the northern part of the West Bank. The aquifer is being used by 128,000 Palestinians to fulfill domestic and agricultural demands. The study takes into account the consequences of pollution and the options the decision maker might face. Since nitrate is the major pollutant in the aquifer, the consequences of nitrate pollution were analyzed, which mainly consists of the possibility of methemoglobinemia (blue baby syndrome). In this case, the value of monitoring was compared to the costs of treating for methemoglobinemia or the costs of other options like water treatment, using bottled water or importing water from outside the aquifer. And finally, an optimal monitoring network that takes into account the uncertainties in recharge (climate), aquifer properties (hydraulic conductivity), pollutant chemical reaction (decay factor), and the value of monitoring is designed by utilizing a sparse Bayesian modeling algorithm called a relevance vector machine.

Perennial filter strips reduce nitrate levels in soil and shallow groundwater after grassland-to-cropland conversion

Treesearch

Xiaobo Zhou; Matthew J. Helmers; Heidi Asbjornsen; Randy Kolka; Mark D. Tomer

2010-01-01

Many croplands planted to perennial grasses under the Conservation Reserve Program are being returned to crop production, and with potential consequences for water quality. The objective of this study was to quantify the impact of grassland-to-cropland conversion on nitrate-nitrogen (NO3-N) concentrations in soil and shallow groundwater and to...

Quantification and mapping of surface residue cover and tillage practices for maize and soybean fields in south central Nebraska-USA using Landsat imagery

USDA-ARS?s Scientific Manuscript database

The area cultivated under conservation tillage practices such as no-till and minimal tillage has recently increased in south central Nebraska (NE). Consequently, changes in some of the impacts of cropping systems on soil such as enhancing soil and water quality, improving soil structures and infiltr...

Assessing impacts of payments for watershed services on sustainability in coupled human and natural systems

Treesearch

Heidi Asbjornsen; Alex S. Mayer; Kelly W. Jones; Theresa Selfa; Leonardo Saenz; Randall K. Kolka; Kathleen E. Halvorsen

2015-01-01

Payments for watershed services (PWS) as a policy tool for enhancing water quality and supply have gained momentum in recent years, but their ability to lead to sustainable watershed outcomes is uncertain. Consequently, the demand for effective monitoring and evaluation (M&E) of PWS impacts on coupled human and natural systems (CHANS) and their implications for...

Appropriate technology and climate change adaptation

NASA Astrophysics Data System (ADS)

Bandala, Erick R.; Patiño-Gomez, Carlos

2016-02-01

Climate change is emerging as the greatest significant environmental problem for the 21st Century and the most important global challenge faced by human kind. Based on evidence recognized by the international scientific community, climate change is already an unquestionable reality, whose first effects are beginning to be measured. Available climate projections and models can assist in anticipating potential far-reaching consequences for development processes. Climatic transformations will impact the environment, biodiversity and water resources, putting several productive processes at risk; and will represent a threat to public health and water availability in quantity and quality.

Acclimations to light quality on plant and leaf level affect the vulnerability of pepper (Capsicum annuum L.) to water deficit.

PubMed

Hoffmann, Anna M; Noga, Georg; Hunsche, Mauricio

2015-03-01

We investigated the influence of light quality on the vulnerability of pepper plants to water deficit. For this purpose plants were cultivated either under compact fluorescence lamps (CFL) or light-emitting diodes (LED) providing similar photon fluence rates (95 µmol m(-2) s(-1)) but distinct light quality. CFL emit a wide-band spectrum with dominant peaks in the green and red spectral region, whereas LEDs offer narrow band spectra with dominant peaks at blue (445 nm) and red (665 nm) regions. After one-week acclimation to light conditions plants were exposed to water deficit by withholding irrigation; this period was followed by a one-week regeneration period and a second water deficit cycle. In general, plants grown under CFL suffered more from water deficit than plants grown under LED modules, as indicated by the impairment of the photosynthetic efficiency of PSII, resulting in less biomass accumulation compared to respective control plants. As affected by water shortage, plants grown under CFL had a stronger decrease in the electron transport rate (ETR) and more pronounced increase in heat dissipation (NPQ). The higher amount of blue light suppressed plant growth and biomass formation, and consequently reduced the water demand of plants grown under LEDs. Moreover, pepper plants exposed to high blue light underwent adjustments at chloroplast level (e.g., higher Chl a/Chl b ratio), increasing the photosynthetic performance under the LED spectrum. Differently than expected, stomatal conductance was comparable for water-deficit and control plants in both light conditions during the stress and recovery phases, indicating only minor adjustments at the stomatal level. Our results highlight the potential of the target-use of light quality to induce structural and functional acclimations improving plant performance under stress situations.

Investigation on trophic state index by artificial neural networks (case study: Dez Dam of Iran)

NASA Astrophysics Data System (ADS)

Saghi, H.; Karimi, L.; Javid, A. H.

2015-06-01

Dam construction and surface runoff control is one of the most common approaches for water-needs supply of human societies. However, the increasing development of social activities and hence the subsequent increase in environmental pollutants leads to deterioration of water quality in dam reservoirs and eutrophication process could be intensified. So, the water quality of reservoirs is now one of the key factors in operation and water quality management of reservoirs. Hence, maintaining the quality of the stored water and identification and examination of changes along time has been a constant concern of humans that involves the water authorities. Traditionally, empirical trophic state indices of dam reservoirs often defined based on changes in concentration of effective factors (nutrients) and its consequences (increase in chlorophyll a), have been used as an efficient tool in the definition of dam reservoirs quality. In recent years, modeling techniques such as artificial neural networks have enhanced the prediction capability and the accuracy of these studies. In this study, artificial neural networks have been applied to analyze eutrophication process in the Dez Dam reservoir in Iran. In this paper, feed forward neural network with one input layer, one hidden layer and one output layer was applied using MATLAB neural network toolbox for trophic state index (TSI) analysis in the Dez Dam reservoir. The input data of this network are effective parameters in the eutrophication: nitrogen cycle parameters and phosphorous cycle parameters and parameters that will be changed by eutrophication: Chl a, SD, DO and the output data is TSI. Based on the results from estimation of modified Carlson trophic state index, Dez Dam reservoir is considered to be eutrophic in the early July to mid-November and would be mesotrophic with decrease in temperature. Therefore, a decrease in water quality of the dam reservoir during the warm seasons is expectable. The results indicated that artificial neural network (ANN) is a suitable tool for quality modeling of reservoir of dam and increment and decrement of nutrients in trend of eutrophication. Therefore, ANN is a suitable tool for quality modeling of reservoir of dam.

Application of chemometric methods for assessment and modelling of microbiological quality data concerning coastal bathing water in Greece.

PubMed

Papaioannou, Agelos; Rigas, George; Papastergiou, Panagiotis; Hadjichristodoulou, Christos

2014-12-02

Worldwide, the aim of managing water is to safeguard human health whilst maintaining sustainable aquatic and associated terrestrial, ecosystems. Because human enteric viruses are the most likely pathogens responsible for waterborne diseases from recreational water use, but detection methods are complex and costly for routine monitoring, it is of great interest to determine the quality of coastal bathing water with a minimum cost and maximum safety. This study handles the assessment and modelling of the microbiological quality data of 2149 seawater bathing areas in Greece over 10-year period (1997-2006) by chemometric methods. Cluster analysis results indicated that the studied bathing beaches are classified in accordance with the seasonality in three groups. Factor analysis was applied to investigate possible determining factors in the groups resulted from the cluster analysis, and also two new parameters were created in each group; VF1 includes E. coli, faecal coliforms and total coliforms and VF2 includes faecal streptococci/enterococci. By applying the cluster analysis in each seasonal group, three new groups of coasts were generated, group A (ultraclean), group B (clean) and group C (contaminated). The above analysis is confirmed by the application of discriminant analysis, and proves that chemometric methods are useful tools for assessment and modeling microbiological quality data of coastal bathing water on a large scale, and thus could attribute to effective and economical monitoring of the quality of coastal bathing water in a country with a big number of bathing coasts, like Greece. Significance for public healthThe microbiological protection of coastal bathing water quality is of great interest for the public health authorities as well as for the economy. The present study proves that this protection can be achieved by monitoring only two microbiological parameters, E. coli and faecal streptococci/enterococci instead four microbiological parameters (the two mentioned above plus Total coliforms and Faecal coliforms) that are usually monitored today. As a consequence, countries, especially those with large quantities of coastal bathing sites, can perform microbiological monitoring of their bathing waters by checking only the mentioned two parameters, thus ensuring economies of scale. Thus, funds can be used in other actions to preserve the quality of coastal water and human health. This in turn, would aid in the assessment of the quality of coastal bathing waters and provide a more timely indication of bathing water quality, hence contributing to the immediate health protection of bathers.

Optimizing disinfection by-product monitoring points in a distribution system using cluster analysis.

PubMed

Delpla, Ianis; Florea, Mihai; Pelletier, Geneviève; Rodriguez, Manuel J

2018-06-04

Trihalomethanes (THMs) and Haloacetic Acids (HAAs) are the main groups detected in drinking water and are consequently strictly regulated. However, the increasing quantity of data for disinfection byproducts (DBPs) produced from research projects and regulatory programs remains largely unexploited, despite a great potential for its use in optimizing drinking water quality monitoring to meet specific objectives. In this work, we developed a procedure to optimize locations and periods for DBPs monitoring based on a set of monitoring scenarios using the cluster analysis technique. The optimization procedure used a robust set of spatio-temporal monitoring results on DBPs (THMs and HAAs) generated from intensive sampling campaigns conducted in a residential sector of a water distribution system. Results shows that cluster analysis allows for the classification of water quality in different groups of THMs and HAAs according to their similarities, and the identification of locations presenting water quality concerns. By using cluster analysis with different monitoring objectives, this work provides a set of monitoring solutions and a comparison between various monitoring scenarios for decision-making purposes. Finally, it was demonstrated that the data from intensive monitoring of free chlorine residual and water temperature as DBP proxy parameters, when processed using cluster analysis, could also help identify the optimal sampling points and periods for regulatory THMs and HAAs monitoring. Copyright © 2018 Elsevier Ltd. All rights reserved.

The urban harvest approach as framework and planning tool for improved water and resource cycles.

PubMed

Leusbrock, I; Nanninga, T A; Lieberg, K; Agudelo-Vera, C M; Keesman, K J; Zeeman, G; Rijnaarts, H H M

2015-01-01

Water and resource availability in sufficient quantity and quality for anthropogenic needs represents one of the main challenges in the coming decades. To prepare for upcoming challenges such as increased urbanization and climate change related consequences, innovative and improved resource management concepts are indispensable. In recent years we have developed and applied the urban harvest approach (UHA). The UHA aims to model and quantify the urban water cycle on different temporal and spatial scales. This approach allowed us to quantify the impact of the implementation of water saving measures and new water treatment concepts in cities. In this paper we will introduce the UHA and its application for urban water cycles. Furthermore, we will show first results for an extension to energy cycles and highlight future research items (e.g. nutrients, water-energy-nexus).

Summary of selected U.S. Geological survey data on domestic well water quality for the Centers for Disease Control's National Environmental Public Health Tracking Program

USGS Publications Warehouse

Bartholomay, Roy C.; Carter, Janet M.; Qi, Sharon L.; Squillace, Paul J.; Rowe, Gary L.

2007-01-01

About 10 to 30 percent of the population in most States uses domestic (private) water supply. In many States, the total number of people served by domestic supplies can be in the millions. The water quality of domestic supplies is inconsistently regulated and generally not well characterized. The U.S. Geological Survey (USGS) has two water-quality data sets in the National Water Information System (NWIS) database that can be used to help define the water quality of domestic-water supplies: (1) data from the National Water-Quality Assessment (NAWQA) Program, and (2) USGS State data. Data from domestic wells from the NAWQA Program were collected to meet one of the Program's objectives, which was to define the water quality of major aquifers in the United States. These domestic wells were located primarily in rural areas. Water-quality conditions in these major aquifers as defined by the NAWQA data can be compared because of the consistency of the NAWQA sampling design, sampling protocols, and water-quality analyses. The NWIS database is a repository of USGS water data collected for a variety of projects; consequently, project objectives and analytical methods vary. This variability can bias statistical summaries of contaminant occurrence and concentrations; nevertheless, these data can be used to define the geographic distribution of contaminants. Maps created using NAWQA and USGS State data in NWIS can show geographic areas where contaminant concentrations may be of potential human-health concern by showing concentrations relative to human-health water-quality benchmarks. On the basis of national summaries of detection frequencies and concentrations relative to U.S. Environmental Protection Agency (USEPA) human-health benchmarks for trace elements, pesticides, and volatile organic compounds, 28 water-quality constituents were identified as contaminants of potential human-health concern. From this list, 11 contaminants were selected for summarization of water-quality data in 16 States (grantee States) that were funded by the Environmental Public Health Tracking (EPHT) Program of the Centers for Disease Control and Prevention (CDC). Only data from domestic-water supplies were used in this summary because samples from these wells are most relevant to human exposure for the targeted population. Using NAWQA data, the concentrations of the 11 contaminants were compared to USEPA human-health benchmarks. Using NAWQA and USGS State data in NWIS, the geographic distribution of the contaminants were mapped for the 16 grantee States. Radon, arsenic, manganese, nitrate, strontium, and uranium had the largest percentages of samples with concentrations greater than their human-health benchmarks. In contrast, organic compounds (pesticides and volatile organic compounds) had the lowest percentages of samples with concentrations greater than human-health benchmarks. Results of data retrievals and spatial analysis were compiled for each of the 16 States and are presented in State summaries for each State. Example summary tables, graphs, and maps based on USGS data for New Jersey are presented to illustrate how USGS water-quality and associated ancillary geospatial data can be used by the CDC to address goals and objectives of the EPHT Program.

One Solution to the Arsenic Problem: A Return to Surface (Improved Dug) Wells

PubMed Central

Joya, Sakila Afroz; Mostofa, Golam; Yousuf, Jabed; Islam, Ariful; Elahi, Altab; Mahiuddin, Golam; Rahman, Mahmuder; Quamruzzaman, Quazi

2006-01-01

Arsenic contamination in drinking-water in Bangladesh is a major catastrophe, the consequences of which exceed most other man-made disasters. The national policy encourages the use of surface water as much as possible without encountering the problems of sanitation that led to the use of groundwater in the first place. This paper describes the success of the Dhaka Community Hospital (DCH) team and the procedure in implementing sanitary, arsenic-free, dugwells. The capital cost for running water is US$ 5–6 per person. Sixty-six sanitary dugwells were installed in phases between 2000 and 2004 in Pabna district of Bangladesh where there was a great need of safe water because, in some villages, 90% of tubewells were highly contaminated with arsenic. In total, 1,549 families now have access to safe arsenic-free dugwell water. Some of them have a water-pipe up to their kitchen. All of these were implemented with active participation of community members. They also pay for water-use and are themselves responsible for the maintenance and water quality. The DCH helped the community with installation and maintenance protocol and also with monitoring water quality. The bacteria levels are low but not always zero, and studies are in progress to reduce bacteria by chlorination. PMID:17366778

Multiple stressors threaten the imperiled coastal foundation species eelgrass (Zostera marina) in Chesapeake Bay, USA.

PubMed

Lefcheck, Jonathan S; Wilcox, David J; Murphy, Rebecca R; Marion, Scott R; Orth, Robert J

2017-09-01

Interactions among global change stressors and their effects at large scales are often proposed, but seldom evaluated. This situation is primarily due to lack of comprehensive, sufficiently long-term, and spatially extensive datasets. Seagrasses, which provide nursery habitat, improve water quality, and constitute a globally important carbon sink, are among the most vulnerable habitats on the planet. Here, we unite 31 years of high-resolution aerial monitoring and water quality data to elucidate the patterns and drivers of eelgrass (Zostera marina) abundance in Chesapeake Bay, USA, one of the largest and most valuable estuaries in the world, with an unparalleled history of regulatory efforts. We show that eelgrass area has declined 29% in total since 1991, with wide-ranging and severe ecological and economic consequences. We go on to identify an interaction between decreasing water clarity and warming temperatures as the primary drivers of this trend. Declining clarity has gradually reduced eelgrass cover the past two decades, primarily in deeper beds where light is already limiting. In shallow beds, however, reduced visibility exacerbates the physiological stress of acute warming, leading to recent instances of decline approaching 80%. While degraded water quality has long been known to influence underwater grasses worldwide, we demonstrate a clear and rapidly emerging interaction with climate change. We highlight the urgent need to integrate a broader perspective into local water quality management, in the Chesapeake Bay and in the many other coastal systems facing similar stressors. © 2017 John Wiley & Sons Ltd.

Water intake and beverage consumption of pre-schoolers from six European countries and associations with socio-economic status: the ToyBox-study.

PubMed

Pinket, An-Sofie; De Craemer, Marieke; Maes, Lea; De Bourdeaudhuij, Ilse; Cardon, Greet; Androutsos, Odysseas; Koletzko, Berthold; Moreno, Luis; Socha, Piotr; Iotova, Violeta; Manios, Yannis; Van Lippevelde, Wendy

2016-09-01

To study the quantity and quality of water intake from beverages among pre-schoolers and investigate associations with gender and socio-economic status (SES). Kindergarten-based cross-sectional survey within the large-scale European ToyBox-study. A standardized protocol was used and parents/caregivers filled in sociodemographic data and a semi-quantitative FFQ. Kindergartens in six European countries (Belgium, Bulgaria, Germany, Greece, Poland and Spain). European pre-schoolers (aged 3·5-5·5 years) and their parents/caregivers (n 7051). Mean water intake was 1051 ml/d; plain water, 547 ml/d; plain milk, 241 ml/d; other fruit juice, 104 ml/d; pure fruit juice, 59 ml/d; soft drinks, 55 ml/d; tea, 45 ml/d; sugared and chocolate milk, 37 ml/d; smoothies, 15 ml/d; and light soft drinks, 6 ml/d. Boys had a higher water intake than girls due to a higher consumption of plain water, but more importantly to the consumption of beverages of less quality. Lower-SES pre-schoolers scored better on quantity than high-SES pre-schoolers, but as a consequence of consumption of sugared beverages. Nevertheless, the associations differed by country. The water intake from beverages did not meet the European Food Safety Authority standard of 1280 ml/d; especially in Western European countries water intake from beverages was low. The most important water sources were plain water, milk and fruit juices. Interventions aiming at a proper and sufficient water intake should focus on both quantity and quality. Messages about water and water sources should be clear for everyone and interventions should be sufficiently tailored.

Experimental und numerical investigations on cooling efficiency of Air-Mist nozzles on steel during continuous casting

NASA Astrophysics Data System (ADS)

Arth, G.; Taferner, M.; Bernhard, C.; Michelic, S.

2016-07-01

Cooling strategies in continuous casting of steel can vary from rapid cooling to slow cooling, mainly controlled by adjusting the amount of water sprayed onto the surface of the product. Inadequate adjustment however can lead to local surface undercooling or reheating, leading to surface and inner defects. This paper focuses on cooling efficiency of Air-Mist nozzles on casted steel and the experimental and numerical prediction of surface temperature distributions over the product width. The first part explains the determination of heat transfer coefficients (HTC) on laboratory scale, using a so called nozzle measuring stand (NMS). Based on measured water distributions and determined HTC's for air-mist nozzles using the NMS, surface temperatures are calculated by a transient 2D-model on a simple steel plate, explained in the second part of this paper. Simulations are carried out varying water impact density and spray water distribution, consequently influencing the local HTC distribution over the plate width. Furthermore, these results will be interpreted with regard to their consequence for surface and internal quality of the cast product. The results reveal the difficulty of correct adjustment of the amount of sprayed water, concurrent influencing water distribution and thus changing HTC distribution and surface temperature.

Spatio-temporal variation of stream-aquifer interaction: Effect of a weir construction in Korea

NASA Astrophysics Data System (ADS)

Lee, Hyeonju; Koo, Min-Ho; Kim, Kisu; Kim, Yongcheol

2015-04-01

The Four Major Rivers Restoration Project was conducted to secure sufficient water resources, introduce comprehensive flood control measures, and improve water quality while restore the river ecosystem in Korea. The dredging of river bed and the installation of 16 weirs were done in Han, Geum, Yeongsan, and Nakdong rivers from late 2010 to early 2012 as a part of the project. Groundwater data obtained from 213 groundwater monitoring wells near the four major rivers were used to analyze the impacts of weir construction on the nearby groundwater flow system. The groundwater level and chemical characteristics were analyzed to investigate how the groundwater flow system and water quality changed after the weir construction. The results showed that groundwater level rose immediately following the rise of stream stage after the weir construction. Also, the hydrologic condition of the stream in some upland of the weirs was changed from a gaining to a losing stream. Consequently, the direction of groundwater flow was changed from perpendicular to parallel to the stream, and it swapped the groundwater in the downstream of the weir for the water recharged from the stream. Considering the results, some groundwater quality is expected to be changed and become similar to that of the stream, although the change has been not observed yet. Therefore, both further monitoring of the groundwater quality and hydrogeochemical analysis are required for quantitatively evaluating the effect of the weir.

Continuous water-quality and suspended-sediment transport monitoring in the San Francisco Bay, California, water years 2014–15

USGS Publications Warehouse

Buchanan, Paul A.; Downing-Kunz, Maureen; Schoellhamer, David H.; Livsey, Daniel N.

2018-03-08

The U.S. Geological Survey (USGS) monitors water quality and suspended-sediment transport in the San Francisco Bay (bay) as part of a multi-agency effort to address management, water supply, and ecological concerns. The San Francisco Bay area is home to millions of people, and the bay teems both with resident and with migratory wildlife, plants, and fish. Freshwater mixes with salt water in the bay, which is subject both to riverine influences (floods, droughts, managed reservoir releases and freshwater diversions) and to marine influences (tides, waves, effects of salt water). To understand this environment, the USGS, along with its partners (see “Acknowledgements”), has been monitoring the bay’s waters continuously since 1988. Several water-quality variables are of particular importance to State and Federal resource managers and are monitored at key locations throughout the bay (fig. 1). Salinity, which indicates the relative mixing of fresh and ocean waters in the bay, is derived from specific conductance measurements. Water temperature, along with salinity, affects the density of water, which controls gravity-driven circulation patterns and stratification in the water column. Turbidity, a measure of light scattered from suspended particles in the water, is used to estimate suspended-sediment concentration (SSC). Suspended sediment affects the bay in multiple ways: attenuation of sunlight in the water column, affecting phytoplankton growth; deposition on tidal marsh and intertidal mudflats, which can help sustain these habitats as sea level rises; deposition in ports and shipping channels, which can necessitate dredging; and often, adsorption of contaminants, affecting their distribution and concentrations in the environment. Dissolved oxygen concentration, essential to a healthy ecosystem and a fundamental indicator of water quality, is affected by water temperature, salinity, ecosystem metabolism, tidal currents, and wind. Tidal currents in the bay reverse four times a day, and wind direction and intensity typically vary on a daily cycle. Consequently, salinity, water temperature, SSC, and dissolved-oxygen concentration vary spatially and temporally throughout the bay. Therefore, continuous measurements are needed to observe these changes. The purpose of this fact sheet is to provide information about these variables, as well as internet links to access these continuous water-quality data collected by the USGS.

Water quality status of dugouts from five districts in Northern Ghana: implications for sustainable water resources management in a water stressed tropical savannah environment.

PubMed

Cobbina, Samuel J; Anyidoho, Louis Y; Nyame, Frank; Hodgson, I O A

2010-08-01

This study was primarily aimed at investigating the physicochemical and microbial quality of water in 14 such dugouts from five districts in the northern region of Ghana. Results obtained suggest that except for colour, turbidity, total iron and manganese, many physicochemical parameters were either within or close to the World Health Organisation's acceptable limits for drinking water. Generally, colour ranged from 5 to 750 Hz (mean 175 Hz), turbidity from 0.65 to 568 nephelometric turbidity units (NTU; mean 87.9 NTU), total iron from 0.07 to 7.85 mg/L (mean 1.0 mg/L) and manganese from 0.03 to 1.59 mg/L (mean 0.50 mg/L). Coliform counts in water from all the dugouts in both wet and dry seasons were, however, above the recommended limits for drinking water. Total and faecal coliforms ranged from 125 to 68,000 colony forming units (cfu)/100 mL (mean 10,623 cfu/100 mL) and <1 to 19,000 cfu/100 mL (mean 1,310 cfu /100 mL), respectively. The poor microbial quality, as indicated by the analytically significant presence of coliform bacteria in all samples of dugout water, strongly suggests susceptibility and exposure to waterborne diseases of, and consequent health implications on, the many people who continuously patronise these vital water resources throughout the year. In particular, more proactive sustainable water management options, such as introduction to communities of simple but cost-effective purification techniques for water drawn from dugouts for drinking purposes, education and information dissemination to the water users to ensure environmentally hygienic practices around dugouts, may be needed.

Pathogen transport in groundwater systems: contrasts with traditional solute transport

NASA Astrophysics Data System (ADS)

Hunt, Randall J.; Johnson, William P.

2017-06-01

Water quality affects many aspects of water availability, from precluding use to societal perceptions of fit-for-purpose. Pathogen source and transport processes are drivers of water quality because they have been responsible for numerous outbreaks resulting in large economic losses due to illness and, in some cases, loss of life. Outbreaks result from very small exposure (e.g., less than 20 viruses) from very strong sources (e.g., trillions of viruses shed by a single infected individual). Thus, unlike solute contaminants, an acute exposure to a very small amount of contaminated water can cause immediate adverse health effects. Similarly, pathogens are larger than solutes. Thus, interactions with surfaces and settling become important even as processes important for solutes such as diffusion become less important. These differences are articulated in "Colloid Filtration Theory", a separate branch of pore-scale transport. Consequently, understanding pathogen processes requires changes in how groundwater systems are typically characterized, where the focus is on the leading edges of plumes and preferential flow paths, even if such features move only a very small fraction of the aquifer flow. Moreover, the relatively short survival times of pathogens in the subsurface require greater attention to very fast (<10 year) flow paths. By better understanding the differences between pathogen and solute transport mechanisms discussed here, a more encompassing view of water quality and source water protection is attained. With this more holistic view and theoretical understanding, better evaluations can be made regarding drinking water vulnerability and the relation between groundwater and human health.

Seasonal drought effects on the water quality of the Biobío River, Central Chile.

PubMed

Yevenes, Mariela A; Figueroa, Ricardo; Parra, Oscar

2018-05-01

Quantifying the effect of droughts on ecosystem functions is essential to the development of coastal zone and river management under a changing climate. It is widely acknowledged that climate change is increasing the frequency and intensity of droughts, which can affect important ecosystem services, such as the regional supply of clean water. Very little is understood about how droughts affect the water quality of Chilean high flow rivers. This paper intends to investigate the effect of an, recently identified, unprecedented drought in Chile (2010-2015), on the Biobío River water quality, (36°45'-38°49' S and 71°00'-73°20' W), Central Chile. This river is one of the largest Chilean rivers and it provides abundant freshwater. Water quality (water temperature, pH, dissolved oxygen, electrical conductivity, biological oxygen demand, total suspended solids, chloride, sodium, nutrients, and trace metals), during the drought (2010-2015), was compared with a pre-drought period (2000-2009) over two reaches (upstream and downstream) of the river. Multivariate analysis and seasonal Mann-Kendall trend analyses and a Theil-Sen estimator were employed to analyze trends and slopes of the reaches. Results indicated a significant decreased trend in total suspended solids and a slightly increasing trend in water temperature and EC, major ions, and trace metals (chrome, lead, iron, and cobalt), mainly in summer and autumn during the drought. The reduced variability upstream suggested that nutrient and metal concentrations were more constant than downstream. The results evidenced, due to the close relationship between river discharge and water quality, a slightly decline of the water quality downstream of the Biobío River during drought period, which could be attenuated in a post-drought period. These results displayed that water quality is vulnerable to reductions in flow, through historical and emerging solutes/contaminants and induced pH mobilization. Consequently, seasonal changes and a progressive reduction of river flow affect the ecosystem functionality in this key Chilean river. The outcomes from this research can be used to improve how low flow conditions and the effects of a reduction in the river volume and discharge are assessed, which is the case under the scenario of more frequent drought periods.

Chemical characteristics of Delaware River water, Trenton, New Jersey, to Marcus Hook, Pennsylvania

USGS Publications Warehouse

Durfor, Charles N.; Keighton, Walter B.

1954-01-01

This progress report gives the results of an investigation of the quality of water in the Delaware River from Trenton, N. J. to Marcus Hook, Pa., for the period August 1949 to December 1952. The Delaware River is the principal source of water for the many industries and municipal water supplies along this reach of the river and both industries and municipalities use it for the disposal of their wastes. Consequently, a study of the quality of the water and variations in the quality caused by changes in streamflow, tidal effects, pollution and other factors is important to the many users. In both New Jersey and Pennsylvania steps are being taken to abate pollution, thus it is of more than passing interest to measure the effects of waste treatment on the quality of the Delaware River water. At average or higher rates of streamflow the mineral content of the water increases slightly from Trenton to Marcus Hook. There is little variation in the concentration of dissolved minerals from bank to bank or from top to bottom of the river. At times of protracted low rates of flow the effect of ocean water mixing with the river water may be noted as far upstream as Philadelphia. At such times the salinity is often greater near the bottom of the river than near the top. The increase in chloride concentration upstream from Philadelphia is small compared to the rapid increase downstream from Philadelphia. Temperatures of offshore water vary with the season, but on a given day are substantially uniform throughout the reach of the river from Trenton to Marcus Hook. The water contains less dissolved oxygen as it flows downstream indicating that oxygen is being consumed by oxidizable matter. From Philadelphia downstream there are periods, especially in late summer, when the dissolved oxygen is barely sufficient to meet the oxygen demands of the pollution load.

A case study of dissolved air flotation for seasonal high turbidity water in Korea.

PubMed

Kwon, S B; Ahn, H W; Ahn, C J; Wang, C K

2004-01-01

A DAF (Dissolved-Air-Flotation) process has been designed considering raw water quality characteristics in Korea. Although direct filtration is usually operated, DAF is operated when freshwater algae blooms occur or raw water turbidity becomes high. Pre-sedimentation is operated in case when the raw water turbidity is very high due to rainstorms. A main feature of this plant is that the operation mode can be changed (controlled) based on the characteristics of the raw water to optimize the effluent quality and the operation costs. Treatment capacity (surface loading rate) and efficiency of DAF was found to be better than the conventional sedimentation process. Moreover, low-density particles (algae and alum flocs) are easily separated while the removal of them by sedimentation is more difficult. One of the main concerns for DAF operation is a high raw water turbidity. DAF is not adequate for raw water, which is more turbid than 100 NTU. In order to avoid this problem, pre-sedimentation basins are installed in the DAF plant to decrease the turbidity of the DAF inflow. For simulation of the actual operation, bench and full-scale tests were performed for highly turbid water conditions. Consequently, it is suggested that pre-sedimentation with optimum coagulation prior to DAF is the appropriate treatment scheme.

Conservation practice establishment in two northeast Iowa watersheds: Strategies, water quality implications, and lessons learned

USGS Publications Warehouse

Gassman, Philip W.; Tisl, J.A.; Palas, E.A.; Fields, C.L.; Isenhart, T.M.; Schilling, K.E.; Wolter, C.F.; Seigley, L.S.; Helmers, M.J.

2010-01-01

Coldwater trout streams are important natural resources in northeast Iowa. Extensive efforts have been made by state and federal agencies to protect and improve water quality in northeast Iowa streams that include Sny Magill Creek and Bloody Run Creek, which are located in Clayton County. A series of three water quality projects were implemented in Sny Magill Creek watershed during 1988 to 1999, which were supported by multiple agencies and focused on best management practice (BMP) adoption. Water quality monitoring was performed during 1992 to 2001 to assess the impact of these installed BMPs in the Sny Magill Creek watershed using a paired watershed approach, where the Bloody Run Creek watershed served as the control. Conservation practice adoption still occurred in the Bloody Run Creek watershed during the 10-year monitoring project and accelerated after the project ended, when a multiagency supported water quality project was implemented during 2002 to 2007. Statistical analysis of the paired watershed results using a pre/post model indicated that discharge increased 8% in Sny Magill Creek watershed relative to the Bloody Run Creek watershed, turbidity declined 41%, total suspended sediment declined 7%, and NOx-N (nitrate-nitrogen plus nitrite-nitrogen) increased 15%. Similar results were obtained with a gradual change statistical model.The weak sediment reductions and increased NOx-N levels were both unexpected and indicate that dynamics between adopted BMPs and stream systems need to be better understood. Fish surveys indicate that conditions for supporting trout fisheries have improved in both streams. Important lessons to be taken from the overall study include (1) committed project coordinators, agency collaborators, and landowners/producers are all needed for successful water quality projects; (2) smaller watershed areas should be used in paired studies; (3) reductions in stream discharge may be required in these systems in order for significant sediment load decreases to occur; (4) long-term monitoring on the order of decades can be required to detect meaningful changes in water quality in response to BMP implementation; and (5) all consequences of specific BMPs need to be considered when considering strategies for watershed protection.

River corridor science: Hydrologic exchange and ecological consequences from bedforms to basins

USGS Publications Warehouse

Harvey, Judson; Gooseff, Michael

2015-01-01

Previously regarded as the passive drains of watersheds, over the past 50 years, rivers have progressively been recognized as being actively connected with off-channel environments. These connections prolong physical storage and enhance reactive processing to alter water chemistry and downstream transport of materials and energy. Here we propose river corridor science as a concept that integrates downstream transport with lateral and vertical exchange across interfaces. Thus, the river corridor, rather than the wetted river channel itself, is an increasingly common unit of study. Main channel exchange with recirculating marginal waters, hyporheic exchange, bank storage, and overbank flow onto floodplains are all included under a broad continuum of interactions known as “hydrologic exchange flows.” Hydrologists, geomorphologists, geochemists, and aquatic and terrestrial ecologists are cooperating in studies that reveal the dynamic interactions among hydrologic exchange flows and consequences for water quality improvement, modulation of river metabolism, habitat provision for vegetation, fish, and wildlife, and other valued ecosystem services. The need for better integration of science and management is keenly felt, from testing effectiveness of stream restoration and riparian buffers all the way to reevaluating the definition of the waters of the United States to clarify the regulatory authority under the Clean Water Act. A major challenge for scientists is linking the small-scale physical drivers with their larger-scale fluvial and geomorphic context and ecological consequences. Although the fine scales of field and laboratory studies are best suited to identifying the fundamental physical and biological processes, that understanding must be successfully linked to cumulative effects at watershed to regional and continental scales.

River corridor science: Hydrologic exchange and ecological consequences from bedforms to basins

NASA Astrophysics Data System (ADS)

Harvey, Jud; Gooseff, Michael

2015-09-01

Previously regarded as the passive drains of watersheds, over the past 50 years, rivers have progressively been recognized as being actively connected with off-channel environments. These connections prolong physical storage and enhance reactive processing to alter water chemistry and downstream transport of materials and energy. Here we propose river corridor science as a concept that integrates downstream transport with lateral and vertical exchange across interfaces. Thus, the river corridor, rather than the wetted river channel itself, is an increasingly common unit of study. Main channel exchange with recirculating marginal waters, hyporheic exchange, bank storage, and overbank flow onto floodplains are all included under a broad continuum of interactions known as "hydrologic exchange flows." Hydrologists, geomorphologists, geochemists, and aquatic and terrestrial ecologists are cooperating in studies that reveal the dynamic interactions among hydrologic exchange flows and consequences for water quality improvement, modulation of river metabolism, habitat provision for vegetation, fish, and wildlife, and other valued ecosystem services. The need for better integration of science and management is keenly felt, from testing effectiveness of stream restoration and riparian buffers all the way to reevaluating the definition of the waters of the United States to clarify the regulatory authority under the Clean Water Act. A major challenge for scientists is linking the small-scale physical drivers with their larger-scale fluvial and geomorphic context and ecological consequences. Although the fine scales of field and laboratory studies are best suited to identifying the fundamental physical and biological processes, that understanding must be successfully linked to cumulative effects at watershed to regional and continental scales.

Water shortage and quality of fleshy fruits--making the most of the unavoidable.

PubMed

Ripoll, Julie; Urban, Laurent; Staudt, Michael; Lopez-Lauri, Félicie; Bidel, Luc P R; Bertin, Nadia

2014-08-01

Extreme climatic events, including drought, are predicted to increase in intensity, frequency, and geographic extent as a consequence of global climate change. In general, to grow crops successfully in the future, growers will need to adapt to less available water and to take better advantage of the positive effects of drought. Fortunately, there are positive effects associated with drought. Drought stimulates the secondary metabolism, thereby potentially increasing plant defences and the concentrations of compounds involved in plant quality, particularly taste and health benefits. The role of drought on the production of secondary metabolites is of paramount importance for fruit crops. However, to manage crops effectively under conditions of limited water supply, for example by applying deficit irrigation, growers must consider not only the impact of drought on productivity but also on how plants manage the primary and secondary metabolisms. This question is obviously complex because during water deficit, trade-offs among productivity, defence, and quality depend upon the intensity, duration, and repetition of events of water deficit. The stage of plant development during the period of water deficit is also crucial, as are the effects of other stressors. In addition, growers must rely on relevant indicators of water status, i.e. parameters involved in the relevant metabolic processes, including those affecting quality. Although many reports on the effects of drought on plant function and crop productivity have been published, these issues have not been reviewed thus far. Here, we provide an up-to-date review of current knowledge of the effects of different forms of drought on fruit quality relative to the primary and secondary metabolisms and their interactions. We also review conventional and less conventional indicators of water status that could be used for monitoring purposes, such as volatile compounds. We focus on fruit crops owing to the importance of secondary metabolism in fruit quality and the importance of fruits in the human diet. The issue of defence is also briefly discussed. © The Author 2014. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Impact of Various Biofuel Feedstock Production Scenarios on Water Quality in the Upper Mississippi River Basin

NASA Astrophysics Data System (ADS)

Wu, M.; Demissie, Y.; Yan, E.

2010-12-01

The impact of increased biofuel feedstock production on regional water quality was examined. This study focused on the Upper Mississippi River Basin, from which a majority of U.S. biofuel is currently produced. The production of biofuel from both conventional feedstock and cellulosic feedstock will potentially increase in the near future. Historically, this water basin generates the largest nitrogen loading to the waterway in the United States and is often cited as a main contributor to the anoxic zone in the Gulf of Mexico. To obtain a quantitative and spatial estimate of nutrient burdens at the river basin, a SWAT (Soil and Water Assessment Tool) model application was developed. The model was equipped with an updated nutrient cycle feature and modified model parameters to represent current crop and perennial grass yield as a result of advancements in breeding and biotechnology. Various biofuel feedstock production scenarios were developed to assess the potential environmental implications of increased biofuel production through corn, agriculture residue, and perennial cellulosic feedstock (such as Switchgrass). Major factors were analyzed, including land use changes, feedstock types, fertilizer inputs, soil property, and yield. This tool can be used to identify specific regional factors affecting water quality and examine options to meet the requirement for environmental sustainability, thereby mitigating undesirable environmental consequences while strengthening energy security.

A methodological approach to characterize the resilience of aquatic ecosystems with application to Lake Annecy, France

NASA Astrophysics Data System (ADS)

Pinault, J.-L.; Berthier, F.

2007-01-01

We propose a methodological approach to characterize the resilience of aquatic ecosystems with respect to the evolution of environmental parameters as well as their aptitude to adapt to forcings. This method that is applied to Lake Annecy, France, proceeds in three stages. First, according to the depth, variations of physicochemical parameters versus time are separated into three components related to (1) energy transfer through the surface of the lake, (2) the flow of rivers and springs that feed the lake, and (3) long-term evolution of the benthic zone as a consequence of mineral and organic matter loads. Second, dynamics of the lake are deduced by analyzing the physicochemical parameter components related to the three boundary conditions. Third, a stochastic process associated with the transfer models aims to characterize the resilience of the lakes according to forcings. For Lake Annecy, whose dynamics are representative of oligotrophic stratified lakes controlled by decarbonation processes where turnover and mixing occurring once a year in winter, the major consequence is the impoverishment of dissolved oxygen in deep water in autumn due to a temperature increase of the surface water in summer. The simulation raises relevant questions about whether a connection exists between physicochemical parameters and global warming, which should not induce harmful consequences on water quality and biodiversity in deep water. This methodological approach is general since it does not use any physical conceptual model to predict the hydrosystem behavior but uses directly observed data.

Influence of Lake Stratification Onset on Summer Surface Water Temperature

NASA Astrophysics Data System (ADS)

Woolway, R. I.; Merchant, C. J.

2016-12-01

Summer lake surface water temperatures (LSSWT) are sensitive to climatic warming and have previously been shown to increase at a faster rate than surface air temperatures in some lakes, as a response to thermal stratification occurring earlier in spring. We explore this relationship using a combination of in situ, satellite derived, and simulated temperatures from 144 lakes. Our results demonstrate that LSSWTs of high-latitude and large deep lakes are particularly sensitive to changes in stratification onset and can be expected to display an amplified response to climatic changes in summer air temperature. Climatic modification of LSSWT has numerous consequences for water quality and lake ecosystems, so quantifying this amplified response is important.

Geohydrology of the Standing Rock Indian Reservation, North and South Dakota

USGS Publications Warehouse

Howells, Lewis W.

1982-01-01

Effective improvement of economic and social conditions of Indians living on the Standing Rock Indian Reservation has been hampered by lack of adequate and reliable information about the quantity and quality of water supplies available for development.  Compounding the problem is the recent filling of Oahe Reservoir (now Lake Oahe), which flooded about 55,000 acres of Indian land, and the consequent relocation of many residents.  This report summarizes the results of a water-resources study made at the request of the U.S. Bureau of Indian Affairs.  It is intended to provide some of the needed information on water supplies that could be used to alleviate the problems mentioned.

Effects of land use and municipal wastewater treatment changes on stream water quality.

PubMed

Ha, S R; Bae, M S

2001-07-01

This study was undertaken to analyze the quantitative impact of a municipal wastewater treatment operation on the long-term water quality changes in a tributary of the Han-river, Korea from 1994 to 1999. Changes of land use pattern in the study watershed are quantitatively analyzed on the basis of land use maps that were created by classifying Landsat TM images acquired in April 1994 and March 1999. During this period, the average increase of land use area in terms of residence, cultivation, and barren was 5.89, 0.13, and 0.12%, respectively, and the corresponding decrease in water and forest area was 0.21 and 0.16%. The annual average reductions of BOD, T-N, and T-P by the municipal wastewater treatment operation were about 89, 11 and 27%, respectively. Spatial analysis of the pollution discharge from watershed was undertaken using a geographic information system (GIS) based model. A clear reciprocal relationship was found between the basin-wide self-purification coefficient and the watershed form ratio excepting a catchment area with water drain facilities. Due to land use changes over the five year study period, water quality change in terms of BOD, T-N, and T-P were (+)1.04 mg l(-1) (corresponding to a 13.7% increase of pollution), (+)0.58 mgl(-1) (10.0% increase), and (-)0.01 mg l(-1) (1.6% decrease). On the other hand, the effect of water quality restoration assessed by outward appearance during the same period was about 67.6, 39, and 36.5%, respectively. Consequently, it is understood that total stream water quality recovery in terms of BOD, T-N, and T-P were 81.3, 49.0, and 38.1% respectively, and that this included a negative contribution resulting from increased land use and a positive contribution due to the wastewater treatment operation at Inchon.

Factors controlling stream water nitrate and phosphor loads during precipitation events

NASA Astrophysics Data System (ADS)

Rozemeijer, J. C.; van der Velde, Y.; van Geer, F. G.; de Rooij, G. H.; Broers, H. P.; Bierkens, M. F. P.

2009-04-01

Pollution of surface waters in densely populated areas with intensive land use is a serious threat to their ecological, industrial and recreational utilization. European and national manure policies and several regional and local pilot projects aim at reducing pollution loads to surface waters. For the evaluation of measures, water authorities and environmental research institutes are putting a lot of effort into monitoring surface water quality. Fro regional surface water quality monitoring, the measurement locations are usually situated in the downstream part of the catchment to represent a larger area. The monitoring frequency is usually low (e.g. monthly), due to the high costs for sampling and analysis. As a consequence, human induced trends in nutrient loads and concentrations in these monitoring data are often concealed by the large variability of surface water quality caused by meteorological variations. Because natural surface water quality variability is poorly understood, large uncertainties occur in the estimates of (trends in) nutrient loads or average concentrations. This study aims at uncertainty reduction in the estimates of mean concentrations and loads of N and P from regional monitoring data. For this purpose, we related continuous N and P records of stream water to variations in precipitation, discharge, groundwater level and tube drain discharge. A specially designed multi scale experimental setup was installed in an agricultural lowland catchment in The Netherlands. At the catchment outlet, continuous measurements of water quality and discharge were performed from July 2007-January 2009. At an experimental field within the catchment continuous measurements of precipitation, groundwater levels and tube drain discharges were collected. 20 significant rainfall events with a variety of antecedent conditions, durations and intensities were selected for analysis. Singular and multiple regression analysis was used to identify relations between the continuous N and P records and characteristics of the dynamics of discharge, precipitation, groundwater level and tube drain discharge. From this study, we conclude that generally available and easy to measure explanatory data (such as continuous records of discharge, precipitation and groundwater level) can reduce uncertainty in estimations of N and P loads and mean concentrations. However, for capturing the observed short load pulses of P, continuous or discharge proportional sampling is needed.

Factors controlling stream water nitrate and phosphor loads during precipitation events

NASA Astrophysics Data System (ADS)

Rozemeijer, J.; van der Velde, Y.; van Geer, F.; de Rooij, G. H.; Broers, H.; Bierkens, M. F.

2009-12-01

Pollution of surface waters in densely populated areas with intensive land use is a serious threat to their ecological, industrial and recreational utilization. European and national manure policies and several regional and local pilot projects aim at reducing pollution loads to surface waters. For the evaluation of measures, water authorities and environmental research institutes are putting a lot of effort into monitoring surface water quality. Within regional surface water quality monitoring networks, the measurement locations are usually situated in the downstream part of the catchment to represent a larger area. The monitoring frequency is usually low (e.g. monthly), due to the high costs for sampling and analysis. As a consequence, human induced trends in nutrient loads and concentrations in these monitoring data are often concealed by the large variability of surface water quality caused by meteorological variations. Because this natural variability in surface water quality is poorly understood, large uncertainties occur in the estimates of (trends in) nutrient loads or average concentrations. This study aims at uncertainty reduction in the estimates of mean concentrations and loads of N and P from regional monitoring data. For this purpose, we related continuous records of stream water N and P concentrations to easier and cheaper to collect quantitative data on precipitation, discharge, groundwater level and tube drain discharge. A specially designed multi scale experimental setup was installed in an agricultural lowland catchment in The Netherlands. At the catchment outlet, continuous measurements of water quality and discharge were performed from July 2007-January 2009. At an experimental field within the catchment we collected continuous measurements of precipitation, groundwater levels and tube drain discharges. 20 significant rainfall events with a variety of antecedent conditions, durations and intensities were selected for analysis. Singular and multiple regression analysis were used to identify relations between the N and P response to the rainfall events and the quantitative event characteristics. We successfully used these relations to predict the N and P responses to events and to improve the interpolation between low frequency grab sample measurements. Incorporating the predicted concentration changes during high discharge events dramatically improved the precision of our load estimations.

Pond bank access as an approach for managing toxic cyanobacteria in beef cattle pasture drinking water ponds.

PubMed

Wilson, Alan E; Chislock, Michael F; Yang, Zhen; Barros, Mário U G; Roberts, John F

2018-03-25

Forty-one livestock drinking water ponds in Alabama beef cattle pastures during were surveyed during the late summer to generally understand water quality patterns in these important water resources. Since livestock drinking water ponds are prone to excess nutrients that typically lead to eutrophication, which can promote blooms of toxigenic phytoplankton such as cyanobacteria, we also assessed the threat of exposure to the hepatotoxin, microcystin. Eighty percent of the ponds studied contained measurable microcystin, while three of these ponds had concentrations above human drinking water thresholds set by the US Environmental Protection Agency (i.e., 0.3 μg/L). Water quality patterns in the livestock drinking water ponds contrasted sharply with patterns typically observed for temperate freshwater lakes and reservoirs. Namely, we found several non-linear relationships between phytoplankton abundance (measured as chlorophyll) and nutrients or total suspended solids. Livestock had direct access to all the study ponds. Consequently, the proportion of inorganic suspended solids (e.g., sediment) increased with higher concentrations of total suspended solids, which underlies these patterns. Unimodal relationships were also observed between microcystin and phytoplankton abundance or nutrients. Euglenoids were abundant in the four ponds with chlorophyll concentrations > 250 μg/L (and dominated three of these ponds), which could explain why ponds with high chlorophyll concentrations would have low microcystin concentrations. Based on observations made during sampling events and available water quality data, livestock-mediated bioturbation is causing elevated total suspended solids that lead to reduced phytoplankton abundance and microcystin despite high concentrations of nutrients, such as phosphorus and nitrogen. Thus, livestock could be used to manage algal blooms, including toxic secondary metabolites, in their drinking water ponds by allowing them to walk in the ponds to increase turbidity.

Risk evaluation of available phosphorus loss in agricultural land based on remote sensing and GIS

NASA Astrophysics Data System (ADS)

Ding, Xiaodong; Zhou, Bin; Xu, Junfeng; Liu, Ting; Xie, Bin

2010-09-01

The surplus of phosphorus leads to water eutrophication. Huge input of fertilizers in agricultural activities enriches nutrition in soil. The superfluous nutrient moves easily to riparian water by rainfall and surface runoff; leads to water eutrophication of riparian wetlands and downstream water; and consequently affects ecological balance. Thus it is significant to investigate the risk of phosphorus loss in agricultural land, to identify high concentration areas and guide the management of nutrition loss. This study was implemented mainly in the area of agricultural use in southern Western Australia, where a three-year period preliminary monitoring of water quality showed that the concentration of different forms of phosphorus in water had far exceeded the standard. Due to the large scale surface runoff caused by occasional storms in Western Australia, soil erosion was selected as the main driving factor for the loss of phosphorus. Remote sensing and ground truth data were used to reflect the seasonal changes of plants. The spatial distribution of available phosphorus was then predicted and combined with the evaluation matrix to evaluate the loss risk of phosphorus. This evaluation was based on quantitative rather than qualitative data to make better precision. It could help making decision support for monitoring water quality of rivers and riparian wetlands.

New directions: Future approaches to the standardized assessment of airborne pollutants affecting environmental quality

NASA Astrophysics Data System (ADS)

Nehr, Sascha; Franzen-Reuter, Isabelle; Kucejko, Catharina

2017-10-01

Man-made activities have caused unexampled changes of our environment during the last two centuries. Due to emissions of a vast number of pollutants the composition of the Earth's atmosphere is continuously changing, and the consequences for humans and for ecosystems are only partly understood at present. Once released to the atmosphere, the emitted substances undergo physical and chemical degradation. Many of the substances detected in ambient air are toxic or carcinogenic and might cause respiratory and cardiovascular diseases. Furthermore, air pollutants are influencing acidification, eutrophication, global warming, and biodiversity. Therefore soil quality, water quality, air quality, ecosystem exposure to pollutant deposition, biodiversity, and climate change are coupled problems (Schlesinger, 1997; Steffen et al., 2005; Ehlers et al., 2006; Rockström et al., 2009).

An air pollution modeling study using three surface coverings near the New International Airport of Mexico City.

PubMed

Jazcilevich, Arón D; García, Agustín R; Ruiz-Suárez, Luis-Gerardo

2003-10-01

The dry lakebed of what once was the lake of Texcoco is the location selected for the New International Airport of Mexico City. This project will generate an important urban development near the airport with regional implications on air quality. Using a prognostic air quality model, the consequences of photochemical air pollution in the metropolitan area of Mexico City resulting from three possible coverings for the areas of the lakebed that are not occupied by the runway and terminal building are investigated. These coverings are desert, grassland, and water and occupy an area of 63 km2. This study is based on a representative high pollution episode. In addition to reducing the emission of primary natural particles, the water covering generates a land-water breeze capable of maintaining enough ventilation to reduce pollutant concentrations over a localized region of the metropolitan area and may enhance the wind speed on the coasts of the proposed lake.

Turbidity and nitrate transfer in karstic aquifers in rural areas: the Brionne Basin case-study.

PubMed

Nebbache, S; Feeny, V; Poudevigne, I; Alard, D

2001-08-01

The degradation of water quality in many groundwaters of Europe is a major source of concern. Rises in turbidity and nitrate concentrations represent present or potential threats for the quality of drinking water in rural areas. They are for the most part a consequence of agricultural intensification which has considerably affected land cover and land use in recent decades. In our case-study (a karstic catchment) the mechanisms which explain changes in water quality, as far as turbidity and nitrate are concerned, result from a strong continuity between surface and underground waters. The karstic system of the Brionne Basin can be considered as both the focus of rapid horizontal flows (runoff, a rapid process in which rainwater reaches the spring directly through sinkholes) and slow vertical flows (leaching, in which rainwater filters through the soil to the spring). A hierarchical approach to the water pollution problem of the basin suggests that turbidity or nitrate concentrations peak during heavy rain episodes and are short-term events. In terms of management, this implies that the solution to water pollution caused by such events is also short-term and can therefore be addressed at a local scale. The rise of nitrate concentrations during the past twenty years is the main concern. The solution can only be found at a global scale (all the catchment area must be taken in account: land plots and their spatial configuration), and by taking a long-term approach.

The consequences of tourism for sustainable water use on a tropical island: Zanzibar, Tanzania.

PubMed

Gössling, S

2001-02-01

Many developing countries in the tropics have focused on tourism to generate additional income sources and to diversity the economy. Coastlines in particular have been on the forefront of tourist infrastructure development. Here, the presence of a large number of tourists has often had negative consequences for the sustainable use of the available resources, which in turn has had an effect on the integrity of the ecosystems. In this paper, the situation is described for the use of freshwater resources on the east coast of Zanzibar, Tanzania. This region is water poor, relying on freshwater derived from seasonal rains and stored in less efficient aquifers, which consist of freshwater lenses floating on the underlying seawater. Tourism in the area has grown rapidly in recent years and is expected to further increase in the future. This development is expected to put additional pressure on the freshwater resources of the east coast, which show already signs of over-use. The consequences of overexploitation can include the lowering of the groundwater table, land subsidence, deteriorating groundwater quality, and saltwater intrusion. These, in turn, determine the living conditions in coastal areas and the effects will be felt both by the local populations and the tourist industry. An investigation is made into the causes and consequences of water abstraction by the tourist industry. The results show that present levels of withdrawal are not sustainable, and parts of the local populations are already experiencing water deficits on a daily basis. In the future, if the expected increase in tourist numbers occurs, the pressure on the aquifers will correspondingly increase. The results could be that the tourism in the area becomes unsustainable, which could have an adverse effect on the national economy and also on the local population and environment. Therefore, a precautionary water-management approach is suggested.

Land use change in California, USA: Nonpoint source water quality impacts

NASA Astrophysics Data System (ADS)

Charbonneau, Robert; Kondolf, G. M.

1993-07-01

California’s population increased 25% between 1980 and 1990, resulting in rapid and extensive urbanization. Of a total 123,000 ha urbanized in 42 of the state’s 58 counties between 1984 and 1990, an estimated 13% occurred on irrigated prime farmland, and 48% on wildlands or fallow marginal farmlands. Sixty-six percent of all new irrigated farmland put into production between 1984 and 1990 was of lesser quality than the prime farmland taken out of production by urbanization. Factors dictating the agricultural development of marginal farmlands include the availability and price of water and land, agricultural commodity prices, and technical innovations such as drip irrigation systems that impact the feasibility and costs of production. The increasing amount of marginal farmland being put into production could have significant water quality consequences because marginal lands are generally steeper, have more erodible soils, poorer drainage, and require more fertilizer than prime farmlands. Although no data exist to test our hypothesis, and numerous variables preclude definitive predictions, the evidence suggests that new irrigated marginal lands can increase nonpoint source (NPS) pollution for a given size area by an order of magnitude in some cases.

The Water-Use Implications of a Changing Power Sector

NASA Astrophysics Data System (ADS)

Peer, R.; Sanders, K.

2016-12-01

Changing policies, declining natural gas prices due to shale production and, growing pressure for cleaner energy sources are causing significant shifts in the fuels and technologies utilized for US electricity generation. These shifts have already impacted the volumes of water required for cooling thermal power plants, imposing consequences for watersheds that have yet to be quantified. This research investigates how these regulatory, economic, and socially-driven changes in the power sector have impacted cooling water usage across the US, which currently represents nearly half of US water withdrawals. This study uses plant-specific fuel consumption, generation, and cooling water data to assess water usage trends in the power sector from 2008 to 2014 across HUC-8 hydrologic units. Over this period, transitions from steam-cycle coal and nuclear units towards combined-cycle natural gas units and renewables, as well as transitions from once-through cooling towards wet recirculating tower and dry cooling systems resulted in large shifts in water usage. Trends towards non-traditional cooling water sources such as recycled water reduced freshwater consumption in some watersheds. Although US cooling water withdrawals and consumption increased from 2008 to 2014 largely due to electricity demand growth, the average water withdrawn and consumed per unit of electricity generated decreased and remained similar in magnitude, respectively. Changes at the watershed scale were not uniform, with some experiencing significant water use reductions and environmental benefits, especially due to coal-fired power plant retirements. Results highlight the importance of evaluating both water withdrawals and consumption at local spatial scales, as these shifts have varying consequences on water availability and quality for downstream users and ecosystems. This analysis underscores the importance of prioritizing local water security in global climate change adaptation and mitigation efforts.

Particle Dynamics and Gravel-Bed Adjustments

DTIC Science & Technology

1993-05-01

Freshwater Biological Association Approved for Public Release; distribution unlimited 93- 77903 93 4 1 DISCLAIMER NOTICE THIS DOCUMENT IS BEST QUALITY... FRESHWATER BIOLOGICAL ASSOCTh N" A11PO N NUMBE FERRY HOUSE, FAR SAWREY, AMBLESIDE, CUMBRIA LA22 OLP N/A 9. SPONSORING /MONITORING AGENCY NA45 N¶0DESI...smoothing of the bed and concomitant reduction in hydraulic roughness during the passage of the sheet. Consequent energy slope adjustment caused water

Seagrass meadows in a globally changing environment.

PubMed

Unsworth, Richard K F; van Keulen, Mike; Coles, Rob G

2014-06-30

Seagrass meadows are valuable ecosystem service providers that are now being lost globally at an unprecedented rate, with water quality and other localised stressors putting their future viability in doubt. It is therefore critical that we learn more about the interactions between seagrass meadows and future environmental change in the anthropocene. This needs to be with particular reference to the consequences of poor water quality on ecosystem resilience and the effects of change on trophic interactions within the food web. Understanding and predicting the response of seagrass meadows to future environmental change requires an understanding of the natural long-term drivers of change and how these are currently influenced by anthropogenic stress. Conservation management of coastal and marine ecosystems now and in the future requires increased knowledge of how seagrass meadows respond to environmental change, and how they can be managed to be resilient to these changes. Finding solutions to such issues also requires recognising people as part of the social-ecological system. This special issue aims to further enhance this knowledge by bringing together global expertise across this field. The special issues considers issues such as ecosystem service delivery of seagrass meadows, the drivers of long-term seagrass change and the socio-economic consequences of environmental change to seagrass. Copyright © 2014 Elsevier Ltd. All rights reserved.

[Differences of inherent optical properties of inland lake water body in typical seasons].

PubMed

Sun, De-Yong; Li, Yun-Mei; Wang, Qiao; Le, Cheng-Fen; Huang, Chang-Chun; Wang, Li-Zhen

2008-05-01

Inherent optical property is one of the important properties of water body, which lays the foundation for the establishment of water color analytical models. By using quantity filter technology (QFT) and BB9 backscattering meter, the absorption coefficients of chromophoric dissolved organic matter (CDOM) and total suspended matters (TSM) and the backscattering coefficient of TSM in the water body at Meiliang Bay of Taihu Lake were measured in summer and winter. Based on the spectral comparison of the absorption and backscattering coefficients, their differences between the two seasons were demonstrated, and the reasons that caused these differences were also explored in the context of their relations to the changes in water quality. Consequently, water environment condition could be revealed by using the inherent optical property. The relationship between the backscattering coefficient and the TSM concentration was established, which could provide supporting coefficients to the analytical models to be developed.

Science data in support of environmental health studies in the U.S.-Mexico border region

USGS Publications Warehouse

Buckler, Denny; Strom, Eric

2004-01-01

The border region of the United States and Mexico encompasses a vast and diverse array of physical settings and habitats that include wetlands, deserts, rangeland, mountains, and forests, which are unique in terms of the diversity of their water, mineral, and biological resources. The region is interconnected economically, politically, and socially owing to its binational heritage. In 1995, nearly 11 million people lived immediately adjacent to the border. By one account, that population could more than double by 2020. This rapid population growth and consequent economic development and land-use changes are pushing the limits of environmental sustainability and quality. Infrastructure development has lagged behind the rapid growth of the region, resulting in a shortage of water for municipal, agricultural, and industrial uses. These stressors threaten the quality of life in the region and raise concerns about the interdependence of environmental quality and human health. To allow for continued economic growth while protecting the area’s natural resources and fostering a high quality of life, the United States and Mexico need an improved understanding of the threats posed by these anthropogenic changes.Issues of particular concern include (1) contaminants in ground water, surface water, and biota from agricultural, municipal, and industrial activities; (2) airborne pollutants from fossil-fuel combustion and other activities; (3) contaminants from past and present mining activities and mineral deposits; and (4) pathogens, pharmaceuticals, hormones, and other contaminants released in treated and untreated human and animal wastewaters.

Water resources planning for a river basin with recurrent wildfires.

PubMed

Santos, R M B; Sanches Fernandes, L F; Pereira, M G; Cortes, R M V; Pacheco, F A L

2015-09-01

Situated in the north of Portugal, the Beça River basin is subject to recurrent wildfires, which produce serious consequences on soil erosion and nutrient exports, namely by deteriorating the water quality in the basin. In the present study, the ECO Lab tool embedded in the Mike Hydro Basin software was used for the evaluation of river water quality, in particular the dissolved concentration of phosphorus in the period 1990-2013. The phosphorus concentrations are influenced by the burned area and the river flow discharge, but the hydrologic conditions prevail: in a wet year (2000, 16.3 km(2) of burned area) with an average flow of 16.4 m(3)·s(-1) the maximum phosphorus concentration was as low as 0.02 mg·L(-1), while in a dry year (2005, 24.4 km(2) of burned area) with an average flow of 2 m(3)·s(-1) the maximum concentration was as high as 0.57 mg·L(-1). Phosphorus concentrations in the water bodies exceeded the bounds of good ecological status in 2005 and between 2009 and 2012, water for human consumption in 2009 and water for multiple uses in 2010. The River Covas, a right margin tributary of Beça River, is the most appropriate stream as regards the use of water for human consumption, because it presents the biggest water potential with the best water quality. Since wildfires in the basin result essentially from natural causes and climate change forecasts indicate an increase in their frequency and intensity in the near future, forestry measures are proposed to include as a priority the conversion of stands of maritime pine in mixed stands of conifer and hardwood species. Copyright © 2015 Elsevier B.V. All rights reserved.

Contribution to the study of pollution of soil and water in Oued El Maleh area (Mohammedia, Morocco)

NASA Astrophysics Data System (ADS)

El hajjaji, Souad; Dahchour, Abdelmalek; Belhsaien, Kamal; Zouahri, Abdelmjid; Moussadek, Rachid; Douaik, Ahmed

2016-04-01

In Morocco, diffuse ground and surface water pollution in irrigated areas has caused an increase in the risk of water and soil quality deterioration. This has generated a health and environmental risks. The present study was carried out in the Oued El Maleh region located 65 Km to the south of Rabat on the Moroccan Atlantic coast. It covers a surface area of 310 km2 where agriculture constitutes the main activity of the population. This region is considered as a very important agricultural area, known nationally for its high potential for market gardening. This intensification has been accompanied by an excessive use of agrochemical inputs and poor control of irrigation and drainage. Consequently, salinization phenomena and deterioration of soil structure as well as water are about to create an alarming situation. In order to assess the state of pollution of waters and soil in the region, our study focuses on the determination of physicochemical parameters for the quality of water and soil. The obtained results from sampled wells and surface water show relatively higher values of nitrate and conductivity exceeding Moroccan national standards and revealing net degradation of water quality; therefore the water can be considered not suitable for human consumption and can induce a degradation of soil. The results of the studied soil show that the pH of these soils is weakly to moderately basic; they are usually non-saline with organic matter content moderately filled. Moreover, very high concentrations of nutrients (potassium, phosphorus and nitrogen) were recorded, highlighting poor management fertilizing vegetable crops in the region of Oued El Maleh.

Peat porewater chloride concentration profiles in the Everglades during wet/dry cycles from January 1996 to June 1998: Field measurements and theoretical analysis

USGS Publications Warehouse

Reddy, M.M.; Reddy, M.B.; Kipp, K.L.; Burman, A.; Schuster, P.; Rawlik, P.S.

2008-01-01

Water quality is a key aspect of the Everglades Restoration Project, the largest water reclamation and ecosystem management project proposed in the United States. Movement of nutrients and contaminants to and from Everglades peat porewater could have important consequences for Everglades water quality and ecosystem restoration activities. In a study of Everglades porewater, we observed complex, seasonally variable peat porewater chloride concentration profiles at several locations. Analyses and interpretation of these changing peat porewater chloride concentration profiles identifies processes controlling conservative solute movement at the peat-surface water interface, that is, solutes whose transport is minimally affected by chemical and biological reactions. We examine, with an advection-diffusion model, how alternating wet and dry climatic conditions in the Florida Everglades mediate movement of chloride between peat porewater and marsh surface water. Changing surface water-chloride concentrations alter gradients at the interface between peat and overlying water and hence alter chloride flux across that interface. Surface water chloride concentrations at two frequently monitored sites vary with marsh water depth, and a transfer function was developed to describe daily marsh surface water chloride concentration as a function of marsh water depth. Model results demonstrate that porewater chloride concentrations are driven by changing surface water chloride concentrations, and a sensitivity analysis suggests that inclusion of advective transport in the model improves the agreement between the calculated and the observed chloride concentration profiles. Copyright ?? 2007 John Wiley & Sons, Ltd.

Pathogen transport in groundwater systems: Contrasts with traditional solute transport

USGS Publications Warehouse

Hunt, Randall J.; Johnson, William P.

2017-01-01

Water quality affects many aspects of water availability, from precluding use to societal perceptions of fit-for-purpose. Pathogen source and transport processes are drivers of water quality because they have been responsible for numerous outbreaks resulting in large economic losses due to illness and, in some cases, loss of life. Outbreaks result from very small exposure (e.g., less than 20 viruses) from very strong sources (e.g., trillions of viruses shed by a single infected individual). Thus, unlike solute contaminants, an acute exposure to a very small amount of contaminated water can cause immediate adverse health effects. Similarly, pathogens are larger than solutes. Thus, interactions with surfaces and settling become important even as processes important for solutes such as diffusion become less important. These differences are articulated in “Colloid Filtration Theory”, a separate branch of pore-scale transport. Consequently, understanding pathogen processes requires changes in how groundwater systems are typically characterized, where the focus is on the leading edges of plumes and preferential flow paths, even if such features move only a very small fraction of the aquifer flow. Moreover, the relatively short survival times of pathogens in the subsurface require greater attention to very fast (<10 year) flow paths. By better understanding the differences between pathogen and solute transport mechanisms discussed here, a more encompassing view of water quality and source water protection is attained. With this more holistic view and theoretical understanding, better evaluations can be made regarding drinking water vulnerability and the relation between groundwater and human health.

Ecological risk assessment of nonylphenol in coastal waters of China based on species sensitivity distribution model.

PubMed

Gao, Pei; Li, Zhengyan; Gibson, Mark; Gao, Huiwang

2014-06-01

Nonylphenol (NP) is an endocrine disruptor and causes feminization and carcinogenesis in various organisms. Consequently, the environmental distribution and ecological risks of NP have received wide concern. China accounts for approximately 10% of the total NP usage in the world, but the water quality criteria of NP have not been established in China and the ecological risks of this pollutant cannot be properly assessed. This study thus aims to determine the predicted no effect concentration (PNEC) of NP and to assess the ecological risks of NP in coastal waters of China with the PNEC as water quality criteria. To obtain the HC5 (hazardous concentration for 5% of biological species) and PNEC estimates, the species sensitivity distributions (SSDs) models were built with chronic toxicity data of NP on aquatic organisms screened from the US Environmental Protection Agency (USEPA) ECOTOX database. The results showed that the PNEC for NP in freshwater and seawater was 0.48 μg L(-1) and 0.28 μg L(-1), respectively. The RQ (risk quotient) values of NP in coastal waters of China ranged from 0.01 to 69.7. About 60% of the reported areas showed a high ecological risk with an RQ value ≥ 1.00. NP therefore exists ubiquitously in coastal waters of China and it poses various risks to aquatic ecosystems in the country. This study demonstrates that the SSD methodology can provide a feasible tool for the establishment of water quality criteria for emergent new pollutants when sufficient toxicity data is available. Copyright © 2013 Elsevier Ltd. All rights reserved.

Water quality in South San Francisco Bay, California: current condition and potential issues for the South Bay Salt Pond Restoration Project.

PubMed

Grenier, J Letitia; Davis, Jay A

2010-01-01

The SBSPRP is an extensive tidal wetland restoration project that is underway at the margin of South San Francisco Bay, California. The Project, which aims to restore former salt ponds to tidal marsh and manage other ponds for water bird support, is taking place in the context of a highly urbanized watershed and an Estuary already impacted by chemical contaminants. There is an intimate relationship between water quality in the watershed, the Bay, and the transitional wetland areas where the Project is located. The Project seeks to restore habitat for endangered and endemic species and to provide recreational opportunities for people. Therefore, water quality and bioaccumulation of contaminants in fish and wildlife is an important concern for the success of the Project. Mercury, PCBs, and PBDEs are the persistent contaminants of greatest concern in the region. All of these contaminants are present at elevated concentrations both in the abiotic environment and in wildlife. Dioxins, pyrethroids, PAHs, and selenium are also problematic. Organochlorine insecticides have historically impacted the Bay, and they remain above thresholds for concern in a small proportion of samples. Emerging contaminants, such as PFCs and non-PBDE flame retardants, are also an important water quality issue. Beyond chemical pollutants, other concerns for water quality in South San Francisco Bay exist, and include biological constituents, especially invasive species, and chemical attributes, such as dissolved oxygen and salinity. Future changes, both from within the Project and from the Bay and watershed, are likely to influence water quality in the region. Project actions to restore wetlands could worsen, improve, or not affect the already impaired water quality in South Bay. Accelerated erosion of buried sediment as a consequence of Project restoration actions is a potentially serious regional threat to South Bay water and sediment quality. Furthermore, the planned restoration of salt ponds to tidal marsh has raised concerns about possible increased net production of methylmercury and its subsequent accumulation in the food web. This concern applies not only to the restored marshes, but also to the South Bay as a whole, which could be affected on a regional scale. The ponds that are converted to tidal marsh will sequester millions of cubic meters of sediment. Sequestration of sediment in marshes could remove contaminated sediment from the active zone of the Bay but could also create marshes with contaminated food webs. Some of the ponds will not be restored to marsh but will be managed for use by water birds. Therefore, the effect of dense avian populations on eutrophication and the introduction of pathogens should be considered. Water quality in the Project also could be affected by external changes, such as human population growth and climate change. To address these many concerns related to water quality, the SBSPRP managers, and others faced with management of wetland restoration at a regional scale, should practice adaptive management and ongoing monitoring for water quality, particularly monitoring bioaccumulation of contaminants in the food web.

Quality of water on the Prairie Band Potawatomi Reservation, northeastern Kansas, May 2001 through August 2003

USGS Publications Warehouse

Ross Schmidt, Heather C.

2004-01-01

Water-quality samples were collected from 20 surface-water sites and 11 ground-water sites on the Prairie Band Potawatomi Reservation in northeastern Kansas in an effort to describe existing water-quality conditions on the reservation and to compare water-quality conditions to results from previous reports published as part of a multiyear cooperative study with the Prairie Band Potawatomi Nation. Water is a valuable resource to the Prairie Band Potawatomi Nation as tribal members use the streams draining the reservation, Soldier, Little Soldier, and South Cedar Creeks, to fulfill subsistence hunting and fishing needs and as the tribe develops an economic base on the reservation. Samples were collected once at 20 surface-water monitoring sites during June 2001, and quarterly samples were collected at 5 of the 20 monitoring sites from May 2001 through August 2003. Ground-water-quality samples were collected once from seven wells and twice from four wells during April through May 2003 and in August 2003. Surface-water-quality samples collected from May through August 2001 were analyzed for physical properties, nutrients, pesticides, fecal indicator bacteria, and total suspended solids. In November 2001, an additional analysis for dissolved solids, major ions, trace elements, and suspended-sediment concentration was added for surface-water samples. Ground-water samples were analyzed for physical properties, dissolved solids, major ions, nutrients, trace elements, pesticides, and fecal indicator bacteria. Chemical oxygen demand and volatile organic compounds were analyzed in a sample from one monitoring well located near a construction and demolition landfill on the reservation. Previous reports published as a part of this ongoing study identified total phosphorus, triazine herbicides, and fecal coliform bacteria as exceeding their respective water-quality criteria in surface water on the reservation. Previous ground-water assessments identified occasional sample concentrations of dissolved solids, sodium, sulfate, boron, iron, and manganese as exceeding their respective water-quality criteria. Forty percent of the 65 surface-water samples analyzed for total phosphorus exceeded the aquatic-life goal of 0.1 mg/L (milligrams per liter) established by the U.S. Environmental Protection Agency (USEPA). Concentrations of dissolved solids and sodium occasionally exceeded USEPA Secondary Drinking-Water Regulations and Drinking-Water Advisory Levels, respectively. One of the 20 samples analyzed for atrazine concentrations exceeded the Maximum Contaminant Level (MCL) of 3.0 ?g/L (micrograms per liter) as an annual average established for drinking water by USEPA. A triazine herbicide screen was used on 63 surface-water samples, and triazine compounds were frequently detected. Triazine herbicides and their degradates are listed on the USEPA Contaminant Candidate List. Nitrite plus nitrate concentrations in two ground-water samples from one monitoring well exceeded the MCL of 10 mg/L established by USEPA for drinking water. Arsenic concentrations in two samples from one monitoring well also exceeded the proposed MCL of 10 ?g/L established by the USEPA for drinking water. Concentrations of dissolved solids and sulfate in some ground-water samples exceeded their respective Secondary Drinking-Water Regulations, and concentrations exceeded the taste threshold of the USEPA?s Drinking-Water Advisory Level for sodium. Consequently, in the event that ground water on the reservation is to be used as a drinking-water source, additional treatment may be necessary to remove excess dissolved solids, sulfate, and sodium.

A Qualitative Study on the Interconnected Nature of HIV, Water, and Family.

PubMed

Ramirez-Ortiz, Daisy; Zolnikov, Tara Rava

2017-03-01

Human immunodeficiency virus infection/acquired immunodeficiency syndrome (HIV/AIDS) and poor access to water are two primary global health issues. Poor access to water may significantly affect families infected with HIV and result in adverse social and health consequences. A qualitative study used semi-structured interviews to understand health and social outcomes of families after the implementation of water interventions in rural Kenya. One major sub-theme emerged during this research, which included the effects of water on an HIV-affected family. Prior to the water interventions, common adverse health effects from lack of nutrition, water, and poor hygiene were experienced. After receiving access to water, nutrition and hygiene were improved and additional time was gained and used to reinforce relationships and spread awareness about HIV/AIDS. This study provides need-based evidence for access to safe drinking water in order to decrease adverse health outcomes and improve the quality of life for HIV-affected individuals.

Methodology of risk assessment of loss of water resources due to climate changes

NASA Astrophysics Data System (ADS)

Israfilov, Yusif; Israfilov, Rauf; Guliyev, Hatam; Afandiyev, Galib

2016-04-01

For sustainable development and management of rational use of water resources of Azerbaijan Republic it is actual to forecast their changes taking into account different scenarios of climate changes and assessment of possible risks of loss of sections of water resources. The major part of the Azerbaijani territory is located in the arid climate and the vast majority of water is used in the national economic production. An optimal use of conditional groundwater and surface water is of great strategic importance for economy of the country in terms of lack of common water resources. Low annual rate of sediments, high evaporation and complex natural and hydrogeological conditions prevent sustainable formation of conditioned resources of ground and surface water. In addition, reserves of fresh water resources are not equally distributed throughout the Azerbaijani territory. The lack of the common water balance creates tension in the rational use of fresh water resources in various sectors of the national economy, especially in agriculture, and as a result, in food security of the republic. However, the fresh water resources of the republic have direct proportional dependence on climatic factors. 75-85% of the resources of ground stratum-pore water of piedmont plains and fracture-vein water of mountain regions are formed by the infiltration of rainfall and condensate water. Changes of climate parameters involve changes in the hydrological cycle of the hydrosphere and as a rule, are reflected on their resources. Forecasting changes of water resources of the hydrosphere with different scenarios of climate change in regional mathematical models allowed estimating the extent of their relationship and improving the quality of decisions. At the same time, it is extremely necessary to obtain additional data for risk assessment and management to reduce water resources for a detailed analysis, forecasting the quantitative and qualitative parameters of resources, and also for optimization the use of water resources. In this regard, we have developed the methodology of risk assessment including statistical fuzzy analysis of the relationship "probability-consequences", classification of probabilities, the consequences on degree of severity and risk. The current methodology allow providing the possibility of practical use of the obtained results and giving effectual help in the sustainable development and reduction of risk degree of optimal use of water resources of the republic and, as a consequence, the national strategy of economic development.

"Upstream Thinking": the catchment management approach of a water provider

NASA Astrophysics Data System (ADS)

Grand-Clement, E.; Ross, M.; Smith, D.; Anderson, K.; Luscombe, D.; Le Feuvre, N.; Brazier, R. E.

2012-04-01

Human activities have large impacts on water quality and provision. Water companies throughout the UK are faced with the consequences of poor land management and need to find appropriate solutions to decreasing water quality. This is particularly true in the South West of England, where 93% of the drinking water is sourced from rivers and reservoirs: large areas of drained peatlands (i.e. Exmoor and Dartmoor National Parks) are responsible for a significant input of dissolved organic carbon (DOC) discolouring the water, whilst poorly managed farming activities can lead to diffuse pollution. Alongside the direct environmental implications, poor water quality is partly increasing water treatment costs and will drive significant future investment in additional water treatment, with further repercussions on customers. This highlights the need for water companies throughout the UK, and further afield, to be more involved in catchment management. "Upstream Thinking" is South West Water's (SWW) approach to catchment management, where working with stakeholders to improve water quality upstream aims to avoid increasingly costly solutions downstream. This approach has led the company to invest in two major areas of work: (1) The Farmland programme where problematic farm management practices and potential solutions are identified, typically 40% of the required investment is then offered in exchange for a legal undertaking to maintain the new farm assets in good condition for 25 years; (2) The Mires programme which involves heavy investment in peatland restoration through the blocking of open ditches in order to improve water storage and quality in the long term. From these two projects, it has been clear that stakeholder involvement of groups such as local farmers, the Westcountry Rivers Trust, the Exmoor National Park Authority, the Environment Agency, Natural England and the Exmoor Society is essential, first because it draws in catchment improvement expertise which is not directly held within the company, and second because it shows how local communities and groups are considered and valued by the company. Monitoring changes and providing a solid scientific base is also undertaken to prove the concept and justify any investment. The work carried out so far has highlighted that SWW's collaborative approach to catchment management is changing the relationship between private water suppliers in the UK and stakeholders or groups having an impact on water quality. This results in a progressive move from a situation where the polluter has to pay, to rewarding providers of clean water instead. The value of ecosystem payments of this kind is being discussed with the appropriate authorities (i.e. Natural England, and the Department for Environment, Food and Rural Affairs) so that it can form part of ensuring sustainable water supplies in future, with all the environmental and ecological benefits of clear raw waters in rivers, lakes and streams.

Influence of alkalinity, hardness and dissolved solids on drinking water taste: A case study of consumer satisfaction.

PubMed

Lou, Jie-Chung; Lee, Wei-Li; Han, Jia-Yun

2007-01-01

Two surveys of consumer satisfaction with drinking water conducted by Taiwan Water Supply Corp. are presented in this study. The study results show that although a lot of money was invested to modify traditional treatment processes, over 60% of local residents still avoided drinking tap water. Over half of the respondents felt that sample TT (from the traditional treatment process) was not a good drinking water, whether in the first or second survey, whereas almost 60% of respondents felt that samples PA, PB, CCL and CT (from advanced treatment processes) were good to drink. For all drinking water samples, respondent satisfaction with a sample primarily depended on it having no unpleasant flavors. Taiwan Environmental Protection Administration plans to revise the drinking water quality standards for TH and TDS in the near future. The new standards require a lower TH concentration (from currently 400mg/L (as CaCO(3)) to 150mg/L (as CaCO(3))), and a lower TDS maximum admissible concentration from the current guideline of 600 to 250mg/L. Therefore, this study also evaluated the impacts on drinking water tastes caused by variations in TH and TDS concentrations, and assessed the need to issue more strict drinking water quality standards for TH and TDS. The research results showed that most respondents could not tell the difference in water taste among water samples with different TDS, TH and alkalinity. Furthermore, hardness was found to be inversely associated with cardiovascular diseases and cancers, and complying with more strict standards would lead most water facilities to invest billions of dollars to upgrade their treatment processes. Consequently, in terms of drinking water tastes alone, this study suggested that Taiwan Environmental Protection Administration should conduct more thorough reviews of the scientific literature that provides the rationale for setting standards and reconsider if it is necessary to revise drinking water quality standards for TH and TDS.

The synergistic effect of manure supply and extreme precipitation on surface water quality

NASA Astrophysics Data System (ADS)

Motew, Melissa; Booth, Eric G.; Carpenter, Stephen R.; Chen, Xi; Kucharik, Christopher J.

2018-04-01

Over-enrichment of phosphorus (P) in agroecosystems contributes to eutrophication of surface waters. In the Midwest US and elsewhere, climate change is increasing the frequency of high-intensity precipitation events, which can serve as a primary conduit of P transport within watersheds. Despite uncertainty in their estimates, process-based watershed models are important tools that help characterize watershed hydrology and biogeochemistry and scale up important mechanisms affecting water quality. Using one such model developed for an agricultural watershed in Wisconsin, we conducted a 2 × 2 factorial experiment to test the effects of (high/low) terrestrial P supply (PSUP) and (high/low) precipitation intensity (PREC) on surface water quality. Sixty-year simulations were conducted for each of the four runs, with annual results obtained for watershed average P yield and concentration at the field scale (220 × 220 m grid cells), P load and concentration at the stream scale, and summertime total P concentration (TP) in Lake Mendota. ANOVA results were generated for the 2 × 2 factorial design, with PSUP and PREC treated as categorical variables. The results showed a significant, positive interaction (p < 0.01) between the two drivers for dissolved P concentration at the field and stream scales, and total P concentration at the field, stream, and lake scales. The synergy in dissolved P was linked to nonlinear dependencies between P stored in manure and the daily runoff to rainfall ratio. The synergistic response of dissolved P loss may have important ecological consequences because dissolved P is highly bioavailable. Overall, the results suggest that high levels of terrestrial P supplied as manure can exacerbate water quality problems in the future as the frequency of high-intensity rainfall events increases with a changing climate. Conversely, lowering terrestrial manure P supply may help improve the resilience of surface water quality to extreme events.

Quantifying effects of hydrological and water quality disturbances on fish with food-web modeling

NASA Astrophysics Data System (ADS)

Zhao, Changsen; Zhang, Yuan; Yang, Shengtian; Xiang, Hua; Sun, Ying; Yang, Zengyuan; Yu, Qiang; Lim, Richard P.

2018-05-01

Accurately delineating the effects of hydrological and water quality habitat factors on the aquatic biota will significantly assist the management of water resources and restoration of river ecosystems. However, current models fail to comprehensively consider the effects of multiple habitat factors on the development of fish species. In this study, a dynamic framework for river ecosystems was set up to explore the effects of multiple habitat factors in terms of hydrology and water quality on the fish community in rivers. To achieve this the biomechanical forms of the relationships between hydrology, water quality, and aquatic organisms were determined. The developing processes of the food web without external disturbance were simulated by 208 models, constructed using Ecopath With Ecosim (EWE). These models were then used to analyze changes in biomass (ΔB) of two representative fish species, Opsariichthys bidens and Carassius auratus, which are widely distributed in Asia, and thus have attracted the attention of scholars and stakeholders, due to the consequence of habitat alteration. Results showed that the relationship between the changes in fish biomass and key habitat factors can be expressed in a unified form. T-tests for the unified form revealed that the means of the two data sets of simulated and observed ΔB for these two fish species (O. bidens and C. auratus) were equal at the significance level of 5%. Compared with other ecological dynamic models, our framework includes theories that are easy to understand and has modest requirements for assembly and scientific expertise. Moreover, this framework can objectively assess the influence of hydrological and water quality variance on aquatic biota with simpler theory and little expertise. Therefore, it is easy to be put into practice and can provide a scientific support for decisions in ecological restoration made by river administrators and stakeholders across the world.

The impact of sleep and psychiatric symptoms on alcohol consequences among young adults.

PubMed

Miller, Mary Beth; Van Reen, Eliza; Barker, David H; Roane, Brandy M; Borsari, Brian; McGeary, John E; Seifer, Ronald; Carskadon, Mary A

2017-03-01

Independent lines of research have documented links between psychiatric symptoms and poor sleep quality, psychiatric symptoms and alcohol use, and alcohol use and poor sleep quality. The current study examined the synergistic effect of poor sleep quality and psychiatric symptoms on alcohol-related consequences in heavy-drinking young adults. Matriculating college students reporting at least one heavy drinking episode over the first nine weeks of the semester (N=385, 52% female) were categorized as experiencing 'good' (n=280) versus 'poor' sleep quality (n=105) and screening 'positive' (n=203) or 'negative' (n=182) for a psychiatric disorder. Sleep quality was assessed using the Pittsburgh Sleep Quality Index; psychiatric diagnosis was assessed using the Psychiatric Diagnostic Screening Questionnaire; and alcohol-related consequences were assessed using the Brief Young Adult Alcohol Consequences Questionnaire. General linear models were used to examine the main effects and interaction between sleep quality and psychiatric symptoms on alcohol-related consequences. Sleep quality moderated the association between psychiatric screen and alcohol-related consequences among heavy-drinking college students, such that psychiatric symptoms were associated with more alcohol-related consequences in the context of poor sleep quality. The combination of poor sleep quality and psychiatric symptoms is associated with increased alcohol-related consequences among heavy-drinking college students. Given the significant interaction between these symptoms, healthcare providers are encouraged to screen for the presence of sleep and psychiatric disorders among heavy-drinking young adults and to provide empirically-supported treatments as appropriate. Copyright © 2016 Elsevier Ltd. All rights reserved.

An assessment of quality of water from boreholes in Bindura District, Zimbabwe

NASA Astrophysics Data System (ADS)

Hoko, Zvikomborero

This study assessed the water quality of 144 boreholes in Bindura District in Mashonaland Province of Zimbabwe as part of a borehole rehabilitation project implemented by a local NGO. In previous studies it has been observed that some boreholes are not used for domestic purposes because of consumer perceived poor water quality. Consequently, communities have resorted to unsafe alternative water sources thus creating health risks. The study was carried out in June 2005. The objectives of the study were to assess the levels of parameters associated with the aesthetics of the water and to compare them with guideline values for drinking water. The study also investigated the relationship between some of the measured water quality and the consumer perceived water quality. Measured water quality parameters included pH, temperature, electrical conductivity (EC), turbidity, calcium (Ca), magnesium (Mg) and iron (Fe). All parameters were measured in the field except Ca, Mg and Fe, which were measured in a laboratory using a spectrophotometer. Consumer perceptions on water quality were investigated through interviews with the consumer community. Turbidity was found to be 0.75-428(20.8 ± 59.2; n = 144) NTU, pH 5.7-9.3 (6.88 ± 0.46; n = 144), temperature 18-26.8 (22.6 ± 2.1; n = 144) °C. EC 26-546 (199 ± 116; n = 144) μS/cm, Ca 6-71.6 (26.9 ± 14.1; n = 81) mg/l, Mg 1.2-49.6 (12.3 ± 10.0; n = 81) mg/l and Fe 0.08-9.60 (0.56 ± 1.15; n = 81) mg/l. Some 23% of the samples had pH outside the recommended range of 6.5-8.5, whilst 59% of the samples had turbidity values exceeding the 5NTU WHO limit. For EC, all samples had values less than the WHO derived limit of 1380 μS/cm. All Ca and magnesium values were within the common and recommended levels of 100 mg/l and 70 mg/l respectively. Iron had values greater than the WHO and SAZ limit of 0.3 mg/l in 36% of the samples. Water quality was deemed satisfactory for taste and soap consumption by 95% and 72% of the respondents respectively. Satisfaction was higher for drinking compared to soap consumption meaning that generally hard waters may still be acceptable for drinking purposes. The water quality met the stipulated standard or guideline value from a minimum of 41% (turbidity) to a maximum of 100% (EC, Ca and Mg). There was no correlation between taste and conductivity as some 5% of the respondents suggested the water was unsatisfactory although all EC values were far below the maximum limit. Again there was no correlation between iron and taste as iron had 36% of the samples above the threshold of 0.3 mg/l whilst objectionable taste perception was only in 5% of the cases. It is recommended that priority in future projects should be given to repairs of boreholes whose water quality is acceptable according to consumer perceptions obtained at project planning stage. Low cost household treatment aimed at improving quality should be investigated.

Drinking Water Consequences Tools. A Literature Review

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

Pasqualini, Donatella

2016-05-12

In support of the goals of Department of Homeland Security’s (DHS) National Protection and Programs Directorate and the Federal Emergency Management Agency, the DHS Office of Science and Technology is seeking to develop and/or modify consequence assessment tools to enable drinking water systems owner/operators to estimate the societal and economic consequences of drinking water disruption due to the threats and hazards. This work will expand the breadth of consequence estimation methods and tools using the best-available data describing water distribution infrastructure, owner/assetlevel economic losses, regional-scale economic activity, and health. In addition, this project will deploy the consequence methodology and capabilitymore » within a Web-based platform. This report is intended to support DHS effort providing a review literature review of existing assessment tools of water and wastewater systems consequences to disruptions. The review includes tools that assess water systems resilience, vulnerability, and risk. This will help to understand gaps and limitations of these tools in order to plan for the development of the next-generation consequences tool for water and waste water systems disruption.« less

Drinking water treatment and risk of cancer death in Wisconsin.

PubMed Central

Kanarek, M S; Young, T B

1982-01-01

A case control study of drinking water treatment practices and female cancer mortality was conducted in Wisconsin. Cancer deaths for 1972-1977 from 28 Wisconsin counties and noncancer deaths matched to cancer deaths on age, year of death and county of residence, were compared for characteristics of drinking water supplied to their places of residence. Using logistic regression, estimates of relative risk associated with chlorinated water were examined allowing for the influence of indicators of water organics and the potential confounders of occupation, marital status and urbanicity. Only colon cancer appeared to be related significantly to chlorination in all models explored. A dose-response relationship was found between crude indicators of trihalomethane level (chlorination X organic contamination) and colon cancer death. The odds ratio for chlorinated surface water for colon cancer was 2.81 (p less than 0.01); approximately half this risk was found for chlorinated ground water. Consequently, a case control study of colon cancer and drinking water quality utilizing newly diagnosed patients is being conducted in Wisconsin. PMID:7151760

Environmental risk assessment of water quality in harbor areas: a new methodology applied to European ports.

PubMed

Gómez, Aina G; Ondiviela, Bárbara; Puente, Araceli; Juanes, José A

2015-05-15

This work presents a standard and unified procedure for assessment of environmental risks at the contaminant source level in port aquatic systems. Using this method, port managers and local authorities will be able to hierarchically classify environmental hazards and proceed with the most suitable management actions. This procedure combines rigorously selected parameters and indicators to estimate the environmental risk of each contaminant source based on its probability, consequences and vulnerability. The spatio-temporal variability of multiple stressors (agents) and receptors (endpoints) is taken into account to provide accurate estimations for application of precisely defined measures. The developed methodology is tested on a wide range of different scenarios via application in six European ports. The validation process confirms its usefulness, versatility and adaptability as a management tool for port water quality in Europe and worldwide. Copyright © 2015 Elsevier Ltd. All rights reserved.

Assessment of global grey water footprint of major food crops

NASA Astrophysics Data System (ADS)

Yang, Hong; Liu, Wenfeng; Antonelli, Marta

2016-04-01

Agricultural production is one of the major sources of water pollution in the world. This is closely related to the excess application of fertilizers. Leaching of N and P to water bodies has caused serious degradation of water quality in many places. With the persistent increase in the demand for agricultural products, agricultural intensification evident during the past decades will continue in the future. This will lead to further increase in fertilizer application and consequently water pollution. Grey water footprint is a measure of the intensity of water pollution caused by water use for human activities. It is defined as the volume of water that is required to assimilate a load of pollutants to a freshwater body, based on natural background concentrations and water quality standards. This study conducts a global assessment of grey water footprint for major cereal crops, wheat, maize and rice. A crop model, Python-based EPIC (PEPIT), is applied to quantify the leaching of N and P from the fertilizer application in the three crops on a global scale with 0.5 degree spatial resolution. The hotspots of leaching are identified. The results suggest that, based on the definition and method of grey water footprint proposed by the World Water Footprint Network, the grey water footprint in many parts of the world has exceeded their total water resources availability. This indicates the seriousness of water pollution caused by agricultural production. However, the situation may also call for the development of a realistic measurement of grey water footprint which is more pertinent to water resources management. This paper proposes some alternatives in measuring grey water footprint and also discusses incorporation of grey water footprint assessment into water policy formulation and river basins plan development.

Effects of land use on quality of water in stratified-drift aquifers in Connecticut

USGS Publications Warehouse

Grady, Stephen J.

1994-01-01

Human activities associated with agricultural, residential, commercial, and industrial land uses have affected the quality of water in the four stratified-drift aquifers examined in Connecticut. A study to evaluate quantitatively the effects of human activities, expressed as land use, on regional ground-water quality was initiated in 1984 as part of the U.S. Geological Survey's Toxic Waste-round-Water Contamination Program. Water-quality data were collected from 116 shallow stainless-steel wells installed beneath or immediately downgradient from seven types of land use areas within the Pootatuck, Pomperaug, Farmington, and Hockanum River valleys in Connecticut. Analysis of variance on the ranked concentrations of 21 largely uncensored or slightly censored constituents, and contingency-table analysis of the frequency of detection of 49 moderately to highly censored constituents indicate that 27 water-quality variables differ at the 0.05 level of significance for samples from at least one land use area. For most constituents, concentrations or detection frequencies are lowest in samples from the undeveloped areas, which characterize background water-quality conditions. The effect of agricultural land use on groundwater quality reflects tillage practices; tilled areas affect the water quality to a greater degree than do untilled areas. Twenty percent of the wells in the tilled agricultural areas yielded water with concentrations of nitrate plus nitrite-nitrogen exceeding 10 milligrams per liter. Atrazine detections in one-third of the wells in areas of tilled agricultural land use were significantly more common than in the undeveloped areas. Ground-water quality beneath sewered residential areas is more severely affected by inorganic and organic nonpoint-source contaminants than is water quality beneath unsewered residential areas. Median concentrations or detection frequencies of most physical properties and inorganic constituents of ground water are higher in sewered than in unsewered residential areas. Generally low concentrations (less than 1.0 microgram per liter) of one or more of 17 volatile organic compounds were detected in samples from 62 percent of the wells in the unsewered residential areas. Most of these compounds were detected in less than 10 percent of the ground-water samples from the unsewered residential areas, however, and consequently, their frequency of detections was not significantly different than in samples from other land use areas. The detection of chloroform in ground-water samples from 47 percent of the wells in the sewered residential areas is significantly higher than the frequency of detection of chloroform in samples from the undeveloped, tilled agricultural, and unsewered residential areas. The quality of ground water is adversely affected beneath commercial areas more so than beneath all other land use areas. Median concentrations of sodium (22.5 milligrams per liter), chloride (36 milligrams per liter), and dissolved solids (286 milligrams per liter) are highest in ground-water samples in commercial areas. Detections of tetrachloroethylene, trichloroethylene, and 1,2-transdichloroethylene were significantly more common in ground-water samples from the commercial areas than in samples from one or more of the other land use areas. Tetrachloroethylene was detected in water samples from 50 percent of the observation wells in the commercial areas at concentrations of up to 1,300 micrograms per liter. Trichloroethylene and 1,2-transdichloroethylene were found at concentrations of up to 20 and 55 micrograms per liter, respectively, in samples from more than 40 percent of the wells in the commercial areas. Although industrial areas occupy only a small part of each of the study areas, they have a disproportionately large effect on ground-water quality. One or more of 12 volatile organic compounds were detected in water samples from 91 percent of the observation wells in the industrial areas

Multi-scale nitrate transport in a sandstone aquifer system under intensive agriculture

NASA Astrophysics Data System (ADS)

Paradis, Daniel; Ballard, Jean-Marc; Lefebvre, René; Savard, Martine M.

2018-03-01

Nitrate transport in heterogeneous bedrock aquifers is influenced by mechanisms that operate at different spatial and temporal scales. To understand these mechanisms in a fractured sandstone aquifer with high porosity, a groundwater-flow and nitrate transport model—reproducing multiple hydraulic and chemical targets—was developed to explain the actual nitrate contamination observed in groundwater and surface water in a study area on Prince Edward Island, Canada. Simulations show that nitrate is leached to the aquifer year-round, with 61% coming from untransformed and transformed organic sources originating from fertilizers and manure. This nitrate reaches the more permeable shallow aquifer through fractures in weathered sandstone that represent only 1% of the total porosity (17%). Some of the nitrate reaches the underlying aquifer, which is less active in terms of groundwater flow, but most of it is drained to the main river. The river-water quality is controlled by the nitrate input from the shallow aquifer. Groundwater in the underlying aquifer, which has long residence times, is also largely influenced by the diffusion of nitrate in the porous sandstone matrix. Consequently, following a change of fertilizer application practices, water quality in domestic wells and the river would change rapidly due to the level of nitrate found in fractures, but a lag time of up to 20 years would be necessary to reach a steady level due to diffusion. This demonstrates the importance of understanding nitrate transport mechanisms when designing effective agricultural and water management plans to improve water quality.

Modeling Study of the Marano and Grado Lagoon (Italy) to Support the Regional Water Protection Plan) TO SUPPORT THE REGIONAL WATER PROTECTION PLAN

NASA Astrophysics Data System (ADS)

Scroccaro, Isabella; Mattassi, Giorgio

2014-05-01

The Water Framework Directive 2000/60/EC (WFD) contemplates the classification of water bodies and establishes the quality objectives of water bodies to achieve a good status within 2015. Further, the Italian law which takes in the WFD with Decree n. 152/2006, allows to identify some water bodies as heavily modified (HMWB). The Regional Administration, involved in the setting up of the Water Protection Plan, according with the above mentioned decree and directive, has to establish specific programs to maintain or conform water quality to the requested quality objectives, also for heavily modified water bodies that have to reach the ecological potential. In the north-eastern part of Italy, in the Friuli Venezia Giulia Region, the Marano and Grado Lagoon is the most complex transitional ecosystem in which four water bodies have been temporarily classified as heavily modified. They are identified as FM1, FM2, FM3 and FM4. In particular, FM2 - "Paludo della Carogna" and FM3 - "Barbana" water bodies seem to be characterized by some confinement since they are delimited by a bridge, called "Ponte Belvedere". The preliminary evaluation of the quality status of FM2 and FM3 water bodies is conditioned by the value of one of the quality criteria: the macrophytes. In fact, macrophytes are represented by very few species in these two water bodies. In a preliminary way the overall judgement of FM2 and FM3 water bodies has been indicated by the experts as scarse. This means that a specific programme of measures has to be proposed to improve the quality status of these water bodies in order to reach the ecological potential. In this context modeling may be used as a scientific and technical tool to support the evaluation on FM2 and FM3 water bodies and the effectiveness of specific measures for the achievement of the quality objectives. Numerical simulations of the Marano and Grado lagoon were performed for hydrodynamic circulation, temperature and salinity behavior with the SHYFEM model, a shallow water finite element model developed at ISMAR-CNR in Venice (Ferrarin et al., 2010) and experimental data were used to calibrate the numerical model. In this study the effectiveness of some proposed measures is investigated with the SHYFEM model, trying to solve the problem of the scarse quality evaluation of FM2 and FM3 in the eastern part of the Marano and Grado lagoon. The proposals are: Modification of the bridge "Ponte Belvedere": the bridge, which divides FM2 and FM3 from the western part of the lagoon, has some openings which are not very large. The proposal is to enlarge these openings on the dam to assess if this action might improve the circulation and consequently the water quality. Excavation of a new channel on the bottom of the lagoon: besides the openings on the dam, it is also possible to hypothetically excavate one or more channels; these are preferential ways for the water to pass in and arrive to the areas in which the circulation has to be increased. This proposal seems to be efficient, with good effects on the inner circulation of the eastern lagoon.

Combining Water Quality and Cost-Benefit Analysis to Examine the Implications of Agricultural Best Management Practices

NASA Astrophysics Data System (ADS)

Rao, N. S.; Easton, Z. M.; Lee, D. R.; Steenhuis, T. S.

2007-12-01

Nutrient runoff from agricultural fields threatens water quality and can impair habitats in many watersheds. Agencies consider these potential risks as they determine acceptable levels of nutrient loading. For example, in the New York City (NYC) watershed, the Environmental Protection Agency's Total Maximum Daily Load (TMDL) for phosphorus (P) has been set at 15μg P L-1 to protect against eutrophication and bacterial outbreaks. In the NYC watersheds agricultural Best Management Practices (BMPs) are the primary means to control nonpoint source P loading. BMPs include riparian buffers, filter strips, manure storage facilities, crop rotation, stripcropping, tree planting and nutrient management plans (NMPs). Water quality research on BMPs to date has included studies on site-specificity of different BMPs, short and long term BMP efficacy, and placement of BMPs with respect to critical source areas. A necessary complement to studies addressing water quality aspects of different BMPs are studies examining the cost-benefit aspects of BMPs. In general, there are installment, maintenance and opportunity costs associated with each BMP, and there are benefits, including cost share agreements between farmers and farm agencies, and increased efficiency of farm production and maintenance. Combining water quality studies and related cost-benefit analyses would help planners and watershed managers determine how best improve water quality. Our research examines the costs-benefit structure associated with BMP scenarios on a one-farm headwater watershed in the Catskill Mountains of NY. The different scenarios include "with and without" BMPs, combinations of BMPs, and different BMP placements across agricultural fields. The costs associated with each BMP scenarios are determined using information from farm agencies and watershed planning agencies. With these data we perform a cost-benefit analysis for the different BMP scenarios and couple the water quality modeling using the Variable Source Loading Function (VSLF) model (Schneiderman et al., 2007) with the cost-benefit analysis to look at the specific water quality and economic consequences of different watershed management scenarios. The results of our study will be useful for planners and watershed managers in determining how best to reduce nonpoint source pollution in a cost-effective manner. References Schneiderman, E.M., T.S. Steenhuis, D.J. Thongs, Z.M. Easton, M.S. Zion, G.F. Mendoza, M.T. Walter, and A.C. Neal. 2007. Incorporating variable source area hydrology into curve number based watershed loading functions. Hydrol. Proc. (In Press).

An integrated modeling framework of socio-economic, biophysical, and hydrological processes in Midwest landscapes: Remote sensing data, agro-hydrological model, and agent-based model

NASA Astrophysics Data System (ADS)

Ding, Deng

Intensive human-environment interactions are taking place in Midwestern agricultural systems. An integrated modeling framework is suitable for predicting dynamics of key variables of the socio-economic, biophysical, hydrological processes as well as exploring the potential transitions of system states in response to changes of the driving factors. The purpose of this dissertation is to address issues concerning the interacting processes and consequent changes in land use, water balance, and water quality using an integrated modeling framework. This dissertation is composed of three studies in the same agricultural watershed, the Clear Creek watershed in East-Central Iowa. In the first study, a parsimonious hydrologic model, the Threshold-Exceedance-Lagrangian Model (TELM), is further developed into RS-TELM (Remote Sensing TELM) to integrate remote sensing vegetation data for estimating evapotranspiration. The goodness of fit of RS-TELM is comparable to a well-calibrated SWAT (Soil and Water Assessment Tool) and even slightly superior in capturing intra-seasonal variability of stream flow. The integration of RS LAI (Leaf Area Index) data improves the model's performance especially over the agriculture dominated landscapes. The input of rainfall datasets with spatially explicit information plays a critical role in increasing the model's goodness of fit. In the second study, an agent-based model is developed to simulate farmers' decisions on crop type and fertilizer application in response to commodity and biofuel crop prices. The comparison between simulated crop land percentage and crop rotations with satellite-based land cover data suggest that farmers may be underestimating the effects that continuous corn production has on yields (yield drag). The simulation results given alternative market scenarios based on a survey of agricultural land owners and operators in the Clear Creek Watershed show that, farmers see cellulosic biofuel feedstock production in the form of perennial grasses or corn stover as a more risky enterprise than their current crop production systems, likely because of market and production risks and lock in effects. As a result farmers do not follow a simple farm-profit maximization rule. In the third study, the consequent water quantity and quality change of the potential land use transitions given alternative biofuel crop market scenarios is explored in a case study in the Clear Creek watershed. A computer program is developed to implement the loose-coupling strategy to couple an agent-based land use model with SWAT. The simulation results show that watershed-scale water quantity (water yield and runoff) and quality variables (sediment and nutrient loads) decrease in values as switchgrass price increases. However, negligence of farmers risk aversions towards biofuel crop adoption would cause overestimation of the impacts of switchgrass price on water quantity and quality.

Consequences of land use and land cover change

USGS Publications Warehouse

Slonecker, E. Terrence; Barnes, Christopher; Karstensen, Krista; Milheim, Lesley E.; Roig-Silva, Coral M.

2013-01-01

The U.S. Geological Survey (USGS) Climate and Land Use Change Mission Area is one of seven USGS mission areas that focuses on making substantial scientific "...contributions to understanding how Earth systems interact, respond to, and cause global change". Using satellite and other remotely sensed data, USGS scientists monitor patterns of land cover change over space and time at regional, national, and global scales. These data are analyzed to understand the causes and consequences of changing land cover, such as economic impacts, effects on water quality and availability, the spread of invasive species, habitats and biodiversity, carbon fluctuations, and climate variability. USGS scientists are among the leaders in the study of land cover, which is a term that generally refers to the vegetation and artificial structures that cover the land surface. Examples of land cover include forests, grasslands, wetlands, water, crops, and buildings. Land use involves human activities that take place on the land. For example, "grass" is a land cover, whereas pasture and recreational parks are land uses that produce a cover of grass.

Irrigation Dynamics and Tactics - Developing a Sustainable and Profitable Irrigation Strategy for Agricultural Areas

NASA Astrophysics Data System (ADS)

Van Opstal, J.; Neale, C. M. U.; Lecina, S.

2014-12-01

Irrigation management is a dynamic process that adapts according to weather conditions and water availability, as well as socio-economic influences. The goal of water users is to adapt their management to achieve maximum profits. However, these decisions should take into account the environmental impact on the surroundings. Agricultural irrigation systems need to be viewed as a system that is an integral part of a watershed. Therefore changes in the infrastructure, operation and management of an irrigated area, has an impact on the water quantity and quality available for other water users. A strategy can be developed for decision-makers using an irrigation system modelling tool. Such a tool can simulate the impact of the infrastructure, operation and management of an irrigation area on its hydrology and agricultural productivity. This combination of factors is successfully simulated with the Ador model, which is able to reproduce on-farm irrigation and water delivery by a canal system. Model simulations for this study are supported with spatial analysis tools using GIS and remote sensing. Continuous measurements of drainage water will be added to indicate the water quality aspects. The Bear River Canal Company located in Northern Utah (U.S.A.) is used as a case study for this research. The irrigation area encompasses 26,000 ha and grows mainly alfalfa, grains, corn and onions. The model allows the simulation of different strategies related to water delivery, on-farm water use, crop rotations, and reservoirs and networks capacities under different weather and water availability conditions. Such changes in the irrigation area will have consequences for farmers in the study area regarding crop production, and for downstream users concerning both the quantity and quality of outflows. The findings from this study give insight to decision-makers and water users for changing irrigation water delivery strategies to improve the sustainability and profitability of agriculture in the future.

Replacing Concrete with Natural and Social Engineering: Learning the Lessons of Stakeholder Engagement from South West Water's Upland Catchment Management Programme

NASA Astrophysics Data System (ADS)

Smith, David; Grand-Clement, Emile; Brazier, Richard

2014-05-01

Replacing Concrete with Natural and Social Engineering: Learning the Lessons of Stakeholder Engagement from South West Water's Upland Catchment Management Programme Smith, D., Grand-Clement, E., Anderson, K., Luscombe, D., G, N., Bratis, Brazier, R.E Peatlands in the South West of the British Isles have been extensively drained for agricultural reclamation and peat cutting. The improvement in food production resulting from this management practice has never clearly been observed. Instead, we are now faced with several detrimental consequences on a whole suite of ecosystem services, such as the delivery of water, water quality, biodiversity and carbon storage. Alongside the direct environmental implications, poor water quality is increasing water treatment costs and will drive significant future investment. As a result, water companies now need to find appropriate solutions to varying water levels and decreasing water quality through catchment management. The Mires Project, the catchment management programme used by South West Water (SWW) is working with a wide range of stakeholders to restore the hydrological functioning of peatlands, and the ecosystem services they provide. This programme is driven by overarching legal requirements (i.e. the water framework directive, Natura 2000), future climate change predictions, corporate responsibility and commercial needs. Post-restoration scientific monitoring is at the heart of the project improving of our understanding of the eco-hydrological and chemical process driving changes in management practice. The challenges faced from the involvement of a wide range of stakeholders will be explored, focusing on the benefits from stakeholder involvement in catchment management and hydrological research, but also considering the difficulties to be overcome. SWW is working with private land-owners, government agencies, local and national park Authorities, community and single interest groups and research institutions to achieve its catchment management objectives. To achieve this it has replaced the traditional water company approach of hard engineering solutions with a mixture of softer natural and social engineering.

Unintended consequences of biofuels production?The effects of large-scale crop conversion on water quality and quantity

USGS Publications Warehouse

Welch, Heather L.; Green, Christopher T.; Rebich, Richard A.; Barlow, Jeannie R.B.; Hicks, Matthew B.

2010-01-01

In the search for renewable fuel alternatives, biofuels have gained strong political momentum. In the last decade, extensive mandates, policies, and subsidies have been adopted to foster the development of a biofuels industry in the United States. The Biofuels Initiative in the Mississippi Delta resulted in a 47-percent decrease in cotton acreage with a concurrent 288-percent increase in corn acreage in 2007. Because corn uses 80 percent more water for irrigation than cotton, and more nitrogen fertilizer is recommended for corn cultivation than for cotton, this widespread shift in crop type has implications for water quantity and water quality in the Delta. Increased water use for corn is accelerating water-level declines in the Mississippi River Valley alluvial aquifer at a time when conservation is being encouraged because of concerns about sustainability of the groundwater resource. Results from a mathematical model calibrated to existing conditions in the Delta indicate that increased fertilizer application on corn also likely will increase the extent of nitrate-nitrogen movement into the alluvial aquifer. Preliminary estimates based on surface-water modeling results indicate that higher application rates of nitrogen increase the nitrogen exported from the Yazoo River Basin to the Mississippi River by about 7 percent. Thus, the shift from cotton to corn may further contribute to hypoxic (low dissolved oxygen) conditions in the Gulf of Mexico.

Assessment of human activities impact on groundwater quality discharging into a reef lagoon

NASA Astrophysics Data System (ADS)

Rebolledo-Vieyra, M.; Hernandez, L.; Paytan, A.; Merino-Ibarra, M.; Lecossec, A.; Soto, M.

2010-03-01

The Eastern coast of the Yucatan Peninsula has the fastest growth rate in Mexico and groundwater is the only source of drinking water in the region. The consequences of the lack of proper infrastructure to collect and treat wastewater and the impact of human activities on the quality of groundwater are addressed. The groundwater in the coastal aquifer of Quintana Roo (SE Mexico) discharges directly into the ocean (Submarine Groundwater Discharges). In addition, the coral reef of the Eastern Yucatan Peninsula is part of the Mesoamerican Coral Reef System, one of the largest in the world. The interaction of the reef-lagoon hydraulics with the coastal aquifer of Puerto Morelos (NE Yucatan Peninsula), and a major input of NH4, SO4, SiO2, as a consequence of the use of septic tanks and the lack of modern wastewater treatment plants are presented. A conceptual model of the coastal aquifer was developed, in order to explain how the human activities are impacting directly on the groundwater quality that, potentially, will have a direct impact on the coral reef. The protection and conservation of coral reefs must be directly related with a policy of sound management of coastal aquifers and wastewater treatment.

Optimizing Noble Gas-Water Interactions via Monte Carlo Simulations.

PubMed

Warr, Oliver; Ballentine, Chris J; Mu, Junju; Masters, Andrew

2015-11-12

In this work we present optimized noble gas-water Lennard-Jones 6-12 pair potentials for each noble gas. Given the significantly different atomic nature of water and the noble gases, the standard Lorentz-Berthelot mixing rules produce inaccurate unlike molecular interactions between these two species. Consequently, we find simulated Henry's coefficients deviate significantly from their experimental counterparts for the investigated thermodynamic range (293-353 K at 1 and 10 atm), due to a poor unlike potential well term (εij). Where εij is too high or low, so too is the strength of the resultant noble gas-water interaction. This observed inadequacy in using the Lorentz-Berthelot mixing rules is countered in this work by scaling εij for helium, neon, argon, and krypton by factors of 0.91, 0.8, 1.1, and 1.05, respectively, to reach a much improved agreement with experimental Henry's coefficients. Due to the highly sensitive nature of the xenon εij term, coupled with the reasonable agreement of the initial values, no scaling factor is applied for this noble gas. These resulting optimized pair potentials also accurately predict partitioning within a CO2-H2O binary phase system as well as diffusion coefficients in ambient water. This further supports the quality of these interaction potentials. Consequently, they can now form a well-grounded basis for the future molecular modeling of multiphase geological systems.

Physical habitat simulation system reference manual: version II

USGS Publications Warehouse

Milhous, Robert T.; Updike, Marlys A.; Schneider, Diane M.

1989-01-01

There are four major components of a stream system that determine the productivity of the fishery (Karr and Dudley 1978). These are: (1) flow regime, (2) physical habitat structure (channel form, substrate distribution, and riparian vegetation), (3) water quality (including temperature), and (4) energy inputs from the watershed (sediments, nutrients, and organic matter). The complex interaction of these components determines the primary production, secondary production, and fish population of the stream reach. The basic components and interactions needed to simulate fish populations as a function of management alternatives are illustrated in Figure I.1. The assessment process utilizes a hierarchical and modular approach combined with computer simulation techniques. The modular components represent the "building blocks" for the simulation. The quality of the physical habitat is a function of flow and, therefore, varies in quality and quantity over the range of the flow regime. The conceptual framework of the Incremental Methodology and guidelines for its application are described in "A Guide to Stream Habitat Analysis Using the Instream Flow Incremental Methodology" (Bovee 1982). Simulation of physical habitat is accomplished using the physical structure of the stream and streamflow. The modification of physical habitat by temperature and water quality is analyzed separately from physical habitat simulation. Temperature in a stream varies with the seasons, local meteorological conditions, stream network configuration, and the flow regime; thus, the temperature influences on habitat must be analysed on a stream system basis. Water quality under natural conditions is strongly influenced by climate and the geological materials, with the result that there is considerable natural variation in water quality. When we add the activities of man, the possible range of water quality possibilities becomes rather large. Consequently, water quality must also be analysed on a stream system basis. Such analysis is outside the scope of this manual, which concentrates on simulation of physical habitat based on depth, velocity, and a channel index. The results form PHABSIM can be used alone or by using a series of habitat time series programs that have been developed to generate monthly or daily habitat time series from the Weighted Usable Area versus streamflow table resulting from the habitat simulation programs and streamflow time series data. Monthly and daily streamflow time series may be obtained from USGS gages near the study site or as the output of river system management models.

Evaluation of Phytoremediation of Coal Bed Methane Product Water and Waters of Quality Similar to that Associated with Coal Bed Methane Reserves of the Powder River Basin, Montana and Wyoming

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

James Bauder

U.S. emphasis on domestic energy independence, along with advances in knowledge of vast biogenically sourced coalbed methane reserves at relatively shallow sub-surface depths with the Powder River Basin, has resulted in rapid expansion of the coalbed methane industry in Wyoming and Montana. Techniques have recently been developed which constitute relatively efficient drilling and methane gas recovery and extraction techniques. However, this relatively efficient recovery requires aggressive reduction of hydrostatic pressure within water-saturated coal formations where the methane is trapped. Water removed from the coal formation during pumping is typically moderately saline and sodium-bicarbonate rich, and managed as an industrial wastemore » product. Current approaches to coalbed methane product water management include: surface spreading on rangeland landscapes, managed irrigation of agricultural crop lands, direct discharge to ephermeral channels, permitted discharge of treated and untreated water to perennial streams, evaporation, subsurface injection at either shallow or deep depths. A Department of Energy-National Energy Technology Laboratory funded research award involved the investigation and assessment of: (1) phytoremediation as a water management technique for waste water produced in association with coalbed methane gas extraction; (2) feasibility of commercial-scale, low-impact industrial water treatment technologies for the reduction of salinity and sodicity in coalbed methane gas extraction by-product water; and (3) interactions of coalbed methane extraction by-product water with landscapes, vegetation, and water resources of the Powder River Basin. Prospective, greenhouse studies of salt tolerance and water use potential of indigenous, riparian vegetation species in saline-sodic environments confirmed the hypothesis that species such as Prairie cordgrass, Baltic rush, American bulrush, and Nuttall's alkaligrass will thrive in saline-sodic environments when water supplies sourced from coalbed methane extraction are plentiful. Constructed wetlands, planted to native, salt tolerant species demonstrated potential to utilize substantial volumes of coalbed methane product water, although plant community transitions to mono-culture and limited diversity communities is a likely consequence over time. Additionally, selected, cultured forage quality barley varieties and native plant species such as Quail bush, 4-wing saltbush, and seaside barley are capable of sustainable, high quality livestock forage production, when irrigated with coalbed methane product water sourced from the Powder River Basin. A consequence of long-term plant water use which was enumerated is elevated salinity and sodicity concentrations within soil and shallow alluvial groundwater into which coalbed methane product water might drain. The most significant conclusion of these investigations was the understanding that phytoremediation is not a viable, effective technique for management of coalbed methane product water under the present circumstances of produced water within the Powder River Basin. Phytoremediation is likely an effective approach to sodium and salt removal from salt-impaired sites after product water discharges are discontinued and site reclamation is desired. Coalbed methane product water of the Powder River Basin is most frequently impaired with respect to beneficial use quality by elevated sodicity, a water quality constituent which can cause swelling, slaking, and dispersion of smectite-dominated clay soils, such as commonly occurring within the Powder River Basin. To address this issue, a commercial-scale fluid-bed, cationic resin exchange treatment process and prototype operating treatment plant was developed and beta-tested by Drake Water Technologies under subcontract to this award. Drake Water Technologies secured U.S. Patent No. 7,368,059-B2, 'Method for removal of benevolent cations from contaminated water', a beta Drake Process Unit (DPU) was developed and deployed for operation in the Powder River Basin. First year operation demonstrated an 84% sodium removal capacity. Greenhouse, laboratory and field research documented substantial likelihood of measurable alteration in soil chemistry, soil physical properties, and shallow alluvial aquifers in and below areas of sustained surface application through irrigation or water spreading or impoundment of coalbed methane product water in evaporation reservoirs within the Basin. Events of repeated wetting and drying of agricultural soils characteristic of the Powder River Basin with coalbed methane product water, followed by infrequent rainfall events, presents high probability circumstances of significant reductions in infiltration capacity and hydraulic conductivity of agricultural soils containing more than 34% smectite clay.« less

Quantitative retrieval of aerosol optical properties by means of ceilometers

NASA Astrophysics Data System (ADS)

Wiegner, Matthias; Gasteiger, Josef; Geiß, Alexander

2016-04-01

In the last few years extended networks of ceilometers have been established by several national weather services. Based on improvements of the hardware performance of these single-wavelength backscatter lidars and their 24/7 availability they are increasingly used to monitor mixing layer heights and to derive profiles of the particle backscatter profile. As a consequence they are used for a wide range of applications including the dispersion of volcanic ash plumes, validation of chemistry transport models and air quality studies. In this context the development of automated schemes to detect aerosol layers and to identify the mixing layer are essential, in particular as the latter is often used as a proxy for air quality. Of equal importance is the calibration of ceilometer signals as a pre-requisite to derive quantitative optical properties. Recently, it has been emphasized that the majority of ceilometers are influenced by water vapor absorption as they operate in the spectral range of 905 - 910 nm. If this effect is ignored, errors of the aerosol backscatter coefficient can be as large as 50%, depending on the atmospheric water vapor content and the emitted wavelength spectrum. As a consequence, any other derived quantity, e.g. the extinction coefficient or mass concentration, would suffer from a significant uncertainty in addition to the inherent errors of the inversion of the lidar equation itself. This can be crucial when ceilometer derived profiles shall be used to validate transport models. In this presentation, the methodology proposed by Wiegner and Gasteiger (2015) to correct for water vapor absorption is introduced and discussed.

Is the replication of somatic coliphages in water environments significant?

PubMed

Jofre, J

2009-04-01

Somatic coliphages are amid several groups of bacteriophages that have been suggested as indicators in water quality assessment. One of the limitations frequently endorsed to somatic coliphages as indicators is that they can replicate in the water environment. This review intends to evaluate the significance of this potential replication. In view of: the threshold densities of somatic coliphages and host bacteria needed for productive infection to occur, the densities of both host cells supporting somatic coliphages replication and these phages in water environments, and the poor contribution of lysogenic induction to the free somatic coliphage numbers in water, it can be concluded that replication of somatic coliphages in waters is very unlikely. Consequently, the contribution of replication in the environment of somatic coliphages is expected to have a non-noticeable influence on the numbers of somatic coliphages detected in water environments. Thus, the replication in the environment should not be argued as a limitation to the use of somatic coliphages as indicators.

Pollution and sanitation problems as setbacks to sustainable water resources management in Freetown.

PubMed

Kallon, Senesie B

2008-12-01

The civil conflict in Sierra Leone (1991-2001) caused a dramatic increase in the population of Freetown. This population increase overstretched housing facilities, leading to the creation of camps and many squatter settlements with poor sanitation practices. Overcrowding has become a serious concern in light of the acute water shortage that struck Freetown in May and June 2006. Some of the numerous small water bodies that could have been used to augment the public water supply were contaminated by the disposal of solid and industrial waste and poor sewage management. Improper disposal practices have a direct impact on public health. This paper recommends addressing the policy gap, establishing clear threshold criteria for all water bodies and wastewater discharge, and integrating the above issues in the ongoing review process of draft water sanitation policy. Public education of the negative consequences of poor waste management practices on water quality and public health can also positively affect general sanitation practices

Communicating ecological importance in a risk-based world: linking numeric nutrient criteria to waterbody expectations

NASA Astrophysics Data System (ADS)

Kaufman, G.; Crawford, T. N.

2016-12-01

To protect the integrity of US waters, the Clean Water Act calls for the development of water quality standards. One key component of standards is limits for pollutants, known as water quality criteria. A cornerstone of deriving water quality criteria is determining how nutrients and other chemicals affect the goals for a waterbody set by a state or tribe, known as designated uses. By establishing a quantifiable and predictable relationship between nutrients and nutrient sensitive organisms and processes, known as assessment endpoints, researchers can help policy makers to address the consequences of pollution in a risk-based, understandable way tied to the goals for a waterbody. Furthermore, public buy-in and effectiveness of criteria can be enhanced by using endpoints to show the connection between nutrient pollution and the uses of waters that are important to the public. This talk will communicate the work done by the US Environmental Protection Agency in cooperation with state, federal, and academic partners to explore the connections between biological and ecological responses and nutrient pollution to derive numeric nutrient criteria in estuarine and coastal waters. The presentation will examine the variety of endpoints that have been used in the work of various research efforts and assessment frameworks. Examples will also be given of numeric nutrient criteria development using assessment endpoints and some of the key decisions that were made during endpoint selection and criteria development will be discussed. Aspects of those decisions that will be presented include development of selection factors for endpoints, data considerations when selecting endpoints, and spatial and temporal representation of endpoints for criteria development. Promising endpoints and future research needs will also be highlighted.

Communicating ecological importance in a risk-based world: linking numeric nutrient criteria to waterbody expectations

NASA Astrophysics Data System (ADS)

Kaufman, G.; Crawford, T. N.

2016-02-01

To protect the integrity of US waters, the Clean Water Act calls for the development of water quality standards. One key component of standards is limits for pollutants, known as water quality criteria. A cornerstone of deriving water quality criteria is determining how nutrients and other chemicals affect the goals for a waterbody set by a state or tribe, known as designated uses. By establishing a quantifiable and predictable relationship between nutrients and nutrient sensitive organisms and processes, known as assessment endpoints, researchers can help policy makers to address the consequences of pollution in a risk-based, understandable way tied to the goals for a waterbody. Furthermore, public buy-in and effectiveness of criteria can be enhanced by using endpoints to show the connection between nutrient pollution and the uses of waters that are important to the public. This talk will communicate the work done by the US Environmental Protection Agency in cooperation with state, federal, and academic partners to explore the connections between biological and ecological responses and nutrient pollution to derive numeric nutrient criteria in estuarine and coastal waters. The presentation will examine the variety of endpoints that have been used in the work of various research efforts and assessment frameworks. Examples will also be given of numeric nutrient criteria development using assessment endpoints and some of the key decisions that were made during endpoint selection and criteria development will be discussed. Aspects of those decisions that will be presented include development of selection factors for endpoints, data considerations when selecting endpoints, and spatial and temporal representation of endpoints for criteria development. Promising endpoints and future research needs will also be highlighted.

Institutional Consequences of Quality Assessment

ERIC Educational Resources Information Center

Joao Rosa, Maria; Tavares, Diana; Amaral, Alberto

2006-01-01

This paper analyses the opinions of Portuguese university rectors and academics on the quality assessment system and its consequences at the institutional level. The results obtained show that university staff (rectors and academics, with more of the former than the latter) held optimistic views of the positive consequences of quality assessment…

Fate of cyanobacteria in drinking water treatment plant lagoon supernatant and sludge.

PubMed

Pestana, Carlos J; Reeve, Petra J; Sawade, Emma; Voldoire, Camille F; Newton, Kelly; Praptiwi, Radisti; Collingnon, Lea; Dreyfus, Jennifer; Hobson, Peter; Gaget, Virginie; Newcombe, Gayle

2016-09-15

In conventional water treatment processes, where the coagulation and flocculation steps are designed to remove particles from drinking water, cyanobacteria are also concentrated into the resultant sludge. As a consequence, cyanobacteria-laden sludge can act as a reservoir for metabolites such as taste and odour compounds and cyanotoxins. This can pose a significant risk to water quality where supernatant from the sludge treatment facility is returned to the inlet to the plant. In this study the complex processes that can take place in a sludge treatment lagoon were investigated. It was shown that cyanobacteria can proliferate in the conditions manifest in a sludge treatment lagoon, and that cyanobacteria can survive and produce metabolites for at least 10days in sludge. The major processes of metabolite release and degradation are very dependent on the physical, chemical and biological environment in the sludge treatment facility and it was not possible to accurately model the net effect. For the first time evidence is provided to suggest that there is a greater risk associated with recycling sludge supernatant than can be estimated from the raw water quality, as metabolite concentrations increased by up to 500% over several days after coagulation, attributed to increased metabolite production and/or cell proliferation in the sludge. Copyright © 2016 Elsevier B.V. All rights reserved.

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EPA Pesticide Factsheets

Under EPA's Water Quality Research Program, exposure studies are needed to determine how well control strategies and guidance are working. Consequently, reliable and convenient techniques that minimize waste production are of special interest. While traditional methods for determining mercury in solid samples involve the use of aggressive chemicals to dissolve the matrix and the use of other chemicals to properly reduce the mercury to the volatile elemental form, pyrolysis-based analyzers can be used by directly weighing the solid in a sampling boat and initiating the instrumental analysis for total mercury. The research focused on in the subtasks is the development and application of state-of the-art technologies to meet the needs of the public, Office of Water, and ORD in the area of Water Quality. Located In the subtasks are the various research projects being performed in support of this Task and more in-depth coverage of each project. Briefly, each project's objective is stated below.Subtask 1: To integrate state-of-the-art technologies (polar organic chemical integrative samplers, advanced solid-phase extraction methodologies with liquid chromatography/electrospray/mass spectrometry) and apply them to studying the sources and fate of a select list of PPCPs. Application and improvement of analytical methodologies that can detect non-volatile, polar, water-soluble pharmaceuticals in source waters at levels that could be environmentally significant (at con

High power vertical stacked and horizontal arrayed diode laser bar development based on insulation micro-channel cooling (IMCC) and hard solder bonding technology

NASA Astrophysics Data System (ADS)

Wang, Boxue; Jia, Yangtao; Zhang, Haoyu; Jia, Shiyin; Liu, Jindou; Wang, Weifeng; Liu, Xingsheng

2018-02-01

An insulation micro-channel cooling (IMCC) has been developed for packaging high power bar-based vertical stack and horizontal array diode lasers, which eliminates many issues caused in its congener packaged by commercial copper formed micro-channel cooler(MCC), such as coefficient of thermal expansion (CTE) mismatch between cooler and diode laser bar, high coolant quality requirement (DI water) and channel corrosion and electro-corrosion induced by DI water if the DI-water quality is not well maintained The IMCC cooler separates water flow route and electrical route, which allows tap-water as coolant without electro-corrosion and therefore prolongs cooler lifetime dramatically and escalated the reliability of these diode lasers. The thickness of ceramic and copper in an IMCC cooler is well designed to minimize the CTE mismatch between laser bar and cooler, consequently, a very low "SMILE" of the laser bar can be achieved for small fast axis divergence after collimation. In additional, gold-tin hard solder bonding technology was also developed to minimize the risk of solder electromigration at high current density and thermal fatigue under hard-pulse operation mode. Testing results of IMCC packaged diode lasers are presented in this report.

Consequences of using different soil texture determination methodologies for soil physical quality and unsaturated zone time lag estimates

NASA Astrophysics Data System (ADS)

Fenton, O.; Vero, S.; Ibrahim, T. G.; Murphy, P. N. C.; Sherriff, S. C.; Ó hUallacháin, D.

2015-11-01

Elucidation of when the loss of pollutants, below the rooting zone in agricultural landscapes, affects water quality is important when assessing the efficacy of mitigation measures. Investigation of this inherent time lag (tT) is divided into unsaturated (tu) and saturated (ts) components. The duration of these components relative to each other differs depending on soil characteristics and the landscape position. The present field study focuses on tu estimation in a scenario where the saturated zone is likely to constitute a higher proportion of tT. In such instances, or where only initial breakthrough (IBT) or centre of mass (COM) is of interest, utilisation of site and depth specific "simple" textural class or actual sand-silt-clay percentages to generate soil water characteristic curves with associated soil hydraulic parameters is acceptable. With the same data it is also possible to estimate a soil physical quality (S) parameter for each soil layer which can be used to infer many other physical, chemical and biological quality indicators. In this study, hand texturing in the field was used to determine textural classes of a soil profile. Laboratory methods, including hydrometer, pipette and laser diffraction methods were used to determine actual sand-silt-clay percentages of sections of the same soil profile. Results showed that in terms of S, hand texturing resulted in a lower index value (inferring a degraded soil) than that of pipette, hydrometer and laser equivalents. There was no difference between S index values determined using the pipette, hydrometer and laser diffraction methods. The difference between the three laboratory methods on both the IBT and COM stages of tu were negligible, and in this instance were unlikely to affect either groundwater monitoring decisions, or to be of consequence from a policy perspective. When tu estimates are made over the full depth of the vadose zone, which may extend to several metres, errors resulting from the use of hydraulic parameters generated from hand texture data will be resultantly greater, and may lead to flawed predictions regarding the achievability of water policy targets. For this reason laboratory analysis, regardless of method, should be preferred to simple field assessments.

The design of sampling transects for characterizing water quality in estuaries

USGS Publications Warehouse

Jassby, A.D.; Cole, B.E.; Cloern, J.E.

1997-01-01

The high spatial variability of estuaries poses a challenge for characterizing estuarine water quality. This problem was examined by conducting monthly high-resolution transects for several water quality variables (chlorophyll a, suspended particulate matter and salinity) in San Francisco Bay (California, U.S.A.). Using these data, six different ways of choosing station locations along a transect, in order to estimate mean conditions, were compared. In addition, 11 approaches to estimating the variance of the transect mean when stations are equally spaced were compared, and the relationship between variance of the estimated transect mean and number of stations was determined. The results provide guidelines for sampling along the axis of an estuary: (1) Choose as many equally-spaced stations as practical; (2) estimate the variance of the mean y?? by var (y??)=(1/10n2)??(j=2)/(n) (y(j)-y(j-1)2, where y1,...,y(n) are the measurements at the n stations; and (3) attain the desired precision by adjusting the number of stations according to var(y??)???1/n2. The inverse power of 2 in the last step is a consequence of the underlying spatial correlation structure in San Francisco Bay; more studies of spatial structure at other estuaries are needed to determine the generality of this relationship.

Evaluation of ATP measurements to detect microbial ingress by wastewater and surface water in drinking water.

PubMed

Vang, Óluva K; Corfitzen, Charlotte B; Smith, Christian; Albrechtsen, Hans-Jørgen

2014-11-01

Fast and reliable methods are required for monitoring of microbial drinking water quality in order to protect public health. Adenosine triphosphate (ATP) was investigated as a potential real-time parameter for detecting microbial ingress in drinking water contaminated with wastewater or surface water. To investigate the ability of the ATP assay in detecting different contamination types, the contaminant was diluted with non-chlorinated drinking water. Wastewater, diluted at 10(4) in drinking water, was detected with the ATP assay, as well as 10(2) to 10(3) times diluted surface water. To improve the performance of the ATP assay in detecting microbial ingress in drinking water, different approaches were investigated, i.e. quantifying microbial ATP or applying reagents of different sensitivities to reduce measurement variations; however, none of these approaches contributed significantly in this respect. Compared to traditional microbiological methods, the ATP assay could detect wastewater and surface water in drinking water to a higher degree than total direct counts (TDCs), while both heterotrophic plate counts (HPC 22 °C and HPC 37 °C) and Colilert-18 (Escherichia coli and coliforms) were more sensitive than the ATP measurements, though with much longer response times. Continuous sampling combined with ATP measurements displays definite monitoring potential for microbial drinking water quality, since microbial ingress in drinking water can be detected in real-time with ATP measurements. The ability of the ATP assay to detect microbial ingress is influenced by both the ATP load from the contaminant itself and the ATP concentration in the specific drinking water. Consequently, a low ATP concentration of the specific drinking water facilitates a better detection of a potential contamination of the water supply with the ATP assay. Copyright © 2014 Elsevier Ltd. All rights reserved.

Fishy Business: Response of Stream Fish Assemblages to Small Hydro-power Plant Induced Flow Alteration in the Western Ghats, Karnataka

NASA Astrophysics Data System (ADS)

Rao, S. T.; Krishnaswamy, J.; Bhalla, R. S.

2017-12-01

Alteration of natural flow regimes is considered as a major threat to freshwater fish assemblages as it disturbs the water quality and micro-habitat features of rivers. Small hydro-power (SHP), which is being promoted as a clean and green substitute for large hydro-power generation, alters the natural flow regime of head-water streams by flow diversion and regulation. The effects of altered flow regime on tropical stream fish assemblages, driven by seasonality induced perturbations to water quality and microhabitat parameters are largely understudied. My study examined the potential consequences of flow alteration by SHPs on fish assemblages in two tributaries of the west-flowing Yettinahole River which flows through the reserved forests of Sakleshpur in the Western Ghats of Karnataka. The flow in one of the tributaries followed natural flow regime while the other comprised three regimes: a near-natural flow regime above the dam, rapidly varying discharge below the dam and a dewatered regime caused by flow diversion. The study found that the altered flow regime differed from natural flow regime in terms of water quality, microhabitat heterogeneity and fish assemblage response, each indicative of the type of flow alteration. Fish assemblage in the natural flow regime was characterized by a higher catch per site, a strong association of endemic and trophic specialist species. The flow regime above the dam was found to mimic some components of the natural flow regime, both ecological and environmental. Non endemic, generalist and pool tolerant species were associated with the dewatered regime. There was a lack of strong species-regime association and an overall low catch per site for the flow regulated regime below the dam. This study highlights the consequences of altered flows on the composition of freshwater fish assemblages and portrays the potential of freshwater fish as indicators of the degree and extent of flow alteration. The study recommends the need for maintaining continuous flow data records to model ecological data with hydrological measurements. In the light of rapid SHP development, the study also suggests environmental / cumulative impact assessments of SHPs on the river basin.

Global sleep quality as a moderator of alcohol consumption and consequences in college students.

PubMed

Kenney, Shannon R; LaBrie, Joseph W; Hummer, Justin F; Pham, Andy T

2012-04-01

The authors examined the relationship between global sleep quality and alcohol risk, including the extent to which global sleep quality moderated the relationship between alcohol use and drinking-related consequences. Global sleep quality was measured using the Pittsburgh Sleep Quality Index (PSQI) and alcohol-related consequences were assessed using the Rutgers Alcohol Problem Index (RAPI). The sample consisted of 261 college students (61.3% female, 58.2% Caucasian) who completed online surveys. Using a four-step hierarchical multiple regression model, global sleep quality was found to predict alcohol consequences, over and above assessed covariates (demographics and weekly drinking). Further, global sleep quality emerged as a strong moderator in the drinking-consequences relationship such that among heavier drinkers, those with poorer global sleep quality experienced significantly greater alcohol-related harm. Campus health education and alcohol interventions may be adapted to address the importance of maintaining a healthy lifestyle, both in terms of healthful sleeping and drinking behaviors, which appear to play a strong synergistic role in alcohol-related risk. Copyright © 2012 Elsevier Ltd. All rights reserved.

Evaluation of water resources around Barapukuria coal mine industrial area, Dinajpur, Bangladesh

NASA Astrophysics Data System (ADS)

Howladar, M. Farhad; Deb, Pulok Kanti; Muzemder, A. T. M. Shahidul Huqe; Ahmed, Mushfique

2014-09-01

Water is a very important natural resource which can be utilized in renewable or non-renewable forms but before utilizing, the evaluation of the quality of this resource is crucial for a particular use. However, the problems of water quality are more severe in areas where the mining and mineral processes' industries are present. In mining processes, several classes of wastes are produced which may turn into ultimately the sources of water quality and environmental degradation. In consequences, the evaluations of water quality for livestock, drinking, irrigation purposes and environmental implications have been carried out around the Barapukuria Coal Mining Industry under different methods and techniques such as primarily the field investigation; secondly the laboratory chemical analysis and thirdly justified the suitability of the laboratory analysis with statistical representation and correlation matrix, Schoeller plot, Piper's Trilinear diagram, Expanded Durov diagram, Wilcox diagram, US salinity diagram, Doneen's chart and others. The results of all surface and ground water samples analysis show that the characteristics and concentrations of all the major physical and chemical parameters such as pH, EC, TDS, Na+, K+, Ca2+, Mg2+, Fetotal, Cl-, HCO3 -, CO3 2- and SO4 2- are varied from one sample to other but well analogous with the WHO and EQS standard limit for all purposes in the area where the abundance of the major ions is as follows: Ca2+ > Na+ > Mg2+ > K+ > Fetotal = HCO3 - > SO4 2- > Cl- > CO3 2-. The graphical exposition of analytical data demonstrates two major hydrochemical facies for example: calcium-bicarbonate (Ca2+- HCO3 -) and magnesium-bicarbonate (Mg2+- HCO3 -) type facies which directly support the shallow recently recharged alkaline water around the industry. The calculated values for the evaluation classification of water based on TDS, Na%, EC, SAR, PI, RSC, MH, and TH replicate good to excellent use of water for livestock, drinking and irrigation activities except in some cases. For example, the high hardness in both water samples specifies the active hydraulic relation between surface and groundwater. Moreover, the statistical application and interpretation exhibit a good positive correlation among most of the water constituents which might be the indicator of having tightly grouped, precise homogeneous good-quality water resources around the mining industry. Finally from the environmental degradation point of view, it can be implied that there are no significant parameters or factors observed which are much badly effective on environment except very few cases. Thus, this research strongly recommends for monitoring the water quality in every 6 months or annually around this industry which might be positive for keeping the safe environment and healthy production of the coal mine.

Water Transfers, Air Quality, Ecosystems and Population Growth at the US-Mexico Border: An Integrated Model of the Mexicali and Imperial Valleys

NASA Astrophysics Data System (ADS)

Forster, C. B.; Gonzalez, T.; Peach, J.; Kjelland, M.; Collins, K.; Grant, W. E.

2006-12-01

Borderland communities in the Imperial-Mexicali Valleys (IMVs) of California (U.S.A.) and Mexicali (Mexico) are experiencing socioeconomic and environmental changes driven by policy makers and environmental conditions both within and outside the IMVs. The Colorado River Quantification Settlement Agreement (QSA) of 2003 will transfer 30 million acre-feet of Colorado River water from Imperial Valley (IV) agricultural users to Southern California urban users over a 75-year period. Because the water level of the Salton Sea is supported by agricultural runoff, reduced water flows to the sea raise concerns that: 1) air quality will be degraded as dust is generated by the drying Sea-bed, and 2) declining fish populations due to increasing salinity will no longer support birds migrating along a key avian flyway. Rapid population growth in the Mexican border-city of Mexicali, combined with new power plants and plans for water reuse, raises concerns that: 1) the quantity and quality of water supplied to the Salton Sea will decline, and 2) increased vehicle use and electrical power generation will lead to declining air quality in the binational air basin. Each concern may be affected by climate change. As environmental factors change, so too may the agricultural economy of the Imperial Valley that, in turn, depends on the availability of both water and manual labor. The economy of Mexicali is dominated by the maquiladora (manufacturing) industry that depends upon the availability of power, labor and water. A system dynamics model, with annual time step, simulates this complex binational system. The model was developed by an academic team with input from local experts/decision-makers from both Mexico and the US. We are preparing to engage community stakeholders and decision-makers in exploring the model. Insights gained from model results yield better understanding of the consequences of alternative future scenarios that include: QSA water transfers and land fallowing plans, socioeconomic change, climate-related variations in future Colorado River flows, plans for Salton Sea restoration, and changing wastewater discharge from Mexicali.

Climate change impact assessment in Veneto and Friuli Plain groundwater. Part II: a spatially resolved regional risk assessment.

PubMed

Pasini, S; Torresan, S; Rizzi, J; Zabeo, A; Critto, A; Marcomini, A

2012-12-01

Climate change impact assessment on water resources has received high international attention over the last two decades, due to the observed global warming and its consequences at the global to local scale. In particular, climate-related risks for groundwater and related ecosystems pose a great concern to scientists and water authorities involved in the protection of these valuable resources. The close link of global warming with water cycle alterations encourages research to deepen current knowledge on relationships between climate trends and status of water systems, and to develop predictive tools for their sustainable management, copying with key principles of EU water policy. Within the European project Life+ TRUST (Tool for Regional-scale assessment of groundwater Storage improvement in adaptation to climaTe change), a Regional Risk Assessment (RRA) methodology was developed in order to identify impacts from climate change on groundwater and associated ecosystems (e.g. surface waters, agricultural areas, natural environments) and to rank areas and receptors at risk in the high and middle Veneto and Friuli Plain (Italy). Based on an integrated analysis of impacts, vulnerability and risks linked to climate change at the regional scale, a RRA framework complying with the Sources-Pathway-Receptor-Consequence (SPRC) approach was defined. Relevant impacts on groundwater and surface waters (i.e. groundwater level variations, changes in nitrate infiltration processes, changes in water availability for irrigation) were selected and analyzed through hazard scenario, exposure, susceptibility and risk assessment. The RRA methodology used hazard scenarios constructed through global and high resolution model simulations for the 2071-2100 period, according to IPCC A1B emission scenario in order to produce useful indications for future risk prioritization and to support the addressing of adaptation measures, primarily Managed Artificial Recharge (MAR) techniques. Relevant outcomes from the described RRA application highlighted that potential climate change impacts will occur with different extension and magnitude in the case study area. Particularly, qualitative and quantitative impacts on groundwater will occur with more severe consequences in the wettest and in the driest scenario (respectively). Moreover, such impacts will likely have little direct effects on related ecosystems - croplands, forests and natural environments - lying along the spring area (about 12% of croplands and 2% of natural environments at risk) while more severe consequences will indirectly occur on natural and anthropic systems through the reduction in quality and quantity of water availability for agricultural and other uses (about 80% of agricultural areas and 27% of groundwater bodies at risk). Copyright © 2012 Elsevier B.V. All rights reserved.

Large outbreak of Cryptosporidium hominis infection transmitted through the public water supply, Sweden.

PubMed

Widerström, Micael; Schönning, Caroline; Lilja, Mikael; Lebbad, Marianne; Ljung, Thomas; Allestam, Görel; Ferm, Martin; Björkholm, Britta; Hansen, Anette; Hiltula, Jari; Långmark, Jonas; Löfdahl, Margareta; Omberg, Maria; Reuterwall, Christina; Samuelsson, Eva; Widgren, Katarina; Wallensten, Anders; Lindh, Johan

2014-04-01

In November 2010, ≈27,000 (≈45%) inhabitants of Östersund, Sweden, were affected by a waterborne outbreak of cryptosporidiosis. The outbreak was characterized by a rapid onset and high attack rate, especially among young and middle-aged persons. Young age, number of infected family members, amount of water consumed daily, and gluten intolerance were identified as risk factors for acquiring cryptosporidiosis. Also, chronic intestinal disease and young age were significantly associated with prolonged diarrhea. Identification of Cryptosporidium hominis subtype IbA10G2 in human and environmental samples and consistently low numbers of oocysts in drinking water confirmed insufficient reduction of parasites by the municipal water treatment plant. The current outbreak shows that use of inadequate microbial barriers at water treatment plants can have serious consequences for public health. This risk can be minimized by optimizing control of raw water quality and employing multiple barriers that remove or inactivate all groups of pathogens.

Large Outbreak of Cryptosporidium hominis Infection Transmitted through the Public Water Supply, Sweden

PubMed Central

Schönning, Caroline; Lilja, Mikael; Lebbad, Marianne; Ljung, Thomas; Allestam, Görel; Ferm, Martin; Björkholm, Britta; Hansen, Anette; Hiltula, Jari; Långmark, Jonas; Löfdahl, Margareta; Omberg, Maria; Reuterwall, Christina; Samuelsson, Eva; Widgren, Katarina; Wallensten, Anders; Lindh, Johan

2014-01-01

In November 2010, ≈27,000 (≈45%) inhabitants of Östersund, Sweden, were affected by a waterborne outbreak of cryptosporidiosis. The outbreak was characterized by a rapid onset and high attack rate, especially among young and middle-aged persons. Young age, number of infected family members, amount of water consumed daily, and gluten intolerance were identified as risk factors for acquiring cryptosporidiosis. Also, chronic intestinal disease and young age were significantly associated with prolonged diarrhea. Identification of Cryptosporidium hominis subtype IbA10G2 in human and environmental samples and consistently low numbers of oocysts in drinking water confirmed insufficient reduction of parasites by the municipal water treatment plant. The current outbreak shows that use of inadequate microbial barriers at water treatment plants can have serious consequences for public health. This risk can be minimized by optimizing control of raw water quality and employing multiple barriers that remove or inactivate all groups of pathogens. PMID:24655474

Comprehensive evaluation of land quality basing on 3S technology and farmers' survey: A case study in Crisscross Region of Wind-drift Sand Regions along the Great Wall and Loess Plateau

NASA Astrophysics Data System (ADS)

Zhang, Yan-yu; Wang, Jing; Shi, Yan-xi; Li, Yu-huan; Lv, Chun-yan

2005-10-01

The Crisscross Region of Wind-drift Sand Regions along the Great Wall and Loess Plateau locates in southern Ordos Plateau and northern Chinese Loess Plateau, where wind erosion and water erosion coexist and specified environmental and socio-economic factors, especially human activities induce serious land degradation. However, there are only a few studies provide an overall assessment consequences. Integrated land quality assessment considering impacts of soil, topography, vegetation, environmental hazards, social-economic factors and land managements are imperative to the regional sustainable land managements. A pilot study was made in Hengshan County (Shanxi Province) with the objective of developing comprehensive land quality evaluation model integrating data from farmers' survey and Remote Sensing. Surveys were carried out in 107 households of study area in 2003 and 2004 to get farmers' perceptions of land quality and to collect correlative information. It was found out that farmers evaluated land quality by slope, water availability, soil texture, yields, amount of fertilizer, crop performance, sandy erosion degree and water erosion degree. Scientists' indicators which emphasize on getting information by RS technology were introduced to reflecting above indicators information for the sake of developing a rapid, efficient and local-fitted land quality assessment model including social-economic, environmental and anthropogenic factors. Data from satellite and surveys were integrated with socio-economic statistic data using geographical information system (GIS) and three indexes, namely Production Press Index (PPI), Land State Index (LSI) and Farmer Behavior Index (FBI) were proposed to measure different aspects of land quality. A model was further derived from the three indexes to explore the overall land quality of the study area. Results suggest that local land prevalently had a poor quality. This paper shows that whilst the model was competent for its work in the study area and evaluation results would supply beneficial information for management decisions.

Urban wet-weather flows: sources of fecal contamination impacting on recreational waters and threatening drinking-water sources.

PubMed

Marsalek, Jiri; Rochfort, Quintin

Discharges of urban stormwater and combined sewer overflows (CSOs) contribute to fecal contamination of urban waters and need to be considered in planning the protection of recreational waters and sources of drinking water. Stormwater characterization indicates that Escherichia coli counts in stormwater typically range from 103 to 104 units per 100 ml. Higher counts (10(5) units/100 ml) suggest the presence of cross-connections with sanitary sewers, and such connections should be identified and corrected. Fecal contamination of stormwater may be attenuated prior to discharge into surface waters by stormwater management measures, which typically remove suspended solids and attached bacteria. Exceptionally, stormwater discharges in the vicinity of swimming beaches are disinfected. The levels of indicator bacteria in CSOs can be as high as 10(6) E. coli per 100 ml. Consequently, the abatement of fecal contamination of CSOs is now considered in the design of CSO control and treatment, as for example stipulated in the Ontario Procedure F-5-5. CSO abatement options comprise combin ations of storage and treatment, in which the CSO treatment generally includes disinfection by ultraviolet (UV) irradiation. Finally, indicator bacteria data from Sarnia (Ontario) were used to demonstrate some fecal contamination impacts of wet-weather flows. In wet weather, the microbiological quality of riverine water worsened as a result of CSO and stormwater discharges, and the recreational water guidelines for indicator organisms were exceeded most of the time. Local improvements in water quality were feasible by source controls and diversion of polluted water.

Water quality and water contamination in the Harlem River

NASA Astrophysics Data System (ADS)

Wang, J.

2015-12-01

Combined sewer overflows (CSOs) discharge untreated sewage into the Harlem River during rainstorms; which elevated nutrient and bacteria/pathogen levels, degraded water quality, reduced dissolved oxygen levels, impact on fish consumption safety and threatening public health. Swimming, boating, fishing was not safe especially during rainstorms. Harlem River, a 9 miles natural straight connects the Hudson River and the East River, was used for water recreation in the past. Phosphate, ammonia, turbidity, dissolved oxygen (DO), and pathogens levels in CSOs collected during storms were significantly higher than EPA/DEP's standards (phosphate <0.033mg/L; ammonia<0.23mg/L; turbidity<5.25FAU; DO>=4mg/L; fecal coliform<200MPN/100ml; E.Coli.<126MPN/100ml; enterococcus < 104MPN /100ml). The maximum values are: phosphate: 0.181mg/L; ammonia: 2.864mg/L; turbidity: 245 FAU& 882 FAU; fecal coliform>millions MPN/100ml; E.coli > 5000MPN /100ml; enterococcus>10,000MPN/100ml; DO<2.9 mg/L. Data showed that pathogen levels are higher than published data from riverkeepers (enterococcus) and USGS (fecal coliform). PCB 11 (3,3'-dichlorobiphenyl, C12H8Cl2), an indicator of raw sewage and stormwater runoff, is analyzed. Fish caught from the Harlem River is banned from commercial. New York State Department of Health (NYS DOH) suggests that not to eat the fish because concerns of PCBs, dioxin and cadmium. How to reduce CSOs is critical on water quality improvement. Green wall/roof and wetland has been planned to use along the river to reduce stormwater runoff consequently to reduce CSOs volume.

Water Quality Control for Shrimp Pond Using Adaptive Neuro Fuzzy Inference System : The First Project

NASA Astrophysics Data System (ADS)

Umam, F.; Budiarto, H.

2018-01-01

Shrimp farming becomes the main commodity of society in Madura Island East Java Indonesia. Because of Madura island has a very extreme weather, farmers have difficulty in keeping the balance of pond water. As a consequence of this condition, there are some farmers experienced losses. In this study an adaptive control system was developed using ANFIS method to control pH balance (7.5-8.5), Temperature (25-31°C), water level (70-120 cm) and Dissolved Oxygen (4-7,5 ppm). Each parameter (pH, temperature, level and DO) is controlled separately but can work together. The output of the control system is in the form of pump activation which provides the antidote to the imbalance that occurs in pond water. The system is built with two modes at once, which are automatic mode and manual mode. The manual control interface based on android which is easy to use.

Water Security Toolkit User Manual: Version 1.3 | Science ...

EPA Pesticide Factsheets

User manual: Data Product/Software The Water Security Toolkit (WST) is a suite of tools that help provide the information necessary to make good decisions resulting in the minimization of further human exposure to contaminants, and the maximization of the effectiveness of intervention strategies. WST assists in the evaluation of multiple response actions in order to select the most beneficial consequence management strategy. It includes hydraulic and water quality modeling software and optimization methodologies to identify: (1) sensor locations to detect contamination, (2) locations in the network in which the contamination was introduced, (3) hydrants to remove contaminated water from the distribution system, (4) locations in the network to inject decontamination agents to inactivate, remove or destroy contaminants, (5) locations in the network to take grab sample to confirm contamination or cleanup and (6) valves to close in order to isolate contaminated areas of the network.

A comparative study on the effectiveness of ozonated water and peracetic acid in the storability of packaged fresh-cut melon.

PubMed

Botondi, Rinaldo; Moscetti, Roberto; Massantini, Riccardo

2016-05-01

Ozonated water and peracetic acid were tested as sanitizers to enhance the storability of fresh-cut melon cubes. Sanitizers were also combined with suitable packaging materials (polypropylene and polylactic acid based plastic films). Fresh-cut melon cubes were stored at 4 °C for up to 7 days. Ozonated water and peracetic acid treatments were given by dipping cubes into 0.8 ppm O3 and 100 ppm Tsunami 100™ solutions, respectively, for 3 min. Both sanitizers exhibited efficiency in reducing the total microbial counts on melon cubes (< 2 log CFU g(-1)). Respiratory activity and ethylene production were both affected by the interaction between the sanitizer and the packaging used. Carbon dioxide and oxygen reached 9.89 kPa and 12.20 kPa partial pressures, respectively, using peracetic acid treatment in combination with polypropylene film packaging, consequently developing off-odors starting from day 3. Strong color changes were noted in cubes stored in polylactic acid packaging after 7 days of storage, affecting the sensory quality of the melon cubes. Sensory evaluation (overall visual quality) indicated loss in flavor in the polypropylene packaging. The overall visual quality started to decline on 3rd day because of the development of translucency.Overall, the use of ozone in combination with polypropylene packaging provided the best solution to maintain the quality of melon cubes for up to 5 days of storage at 4 °C.

Analysis of elemental concentration using ICP-AES and pathogen indicator in drinking water of Qasim Abad, District Rawalpindi, Pakistan.

PubMed

Sehar, Shama; Naz, Iffat; Ali, Naeem; Ahmed, Safia

2013-02-01

The present study was conducted to investigate drinking water quality (groundwater) from water samples taken from Qasim Abad, a locality of approximately 5,000 population, situated between twin cities Rawalpindi and Islamabad in Pakistan. The main sources of drinking water in this area are water bores which are dug upto the depth of 250-280 ft in almost every house. The study consists of the determination of physico-chemical properties, trace metals, heavy metals, rare earth elements and microbiological quality of drinking water. The data showed the variation of the investigated parameters in samples as follows: pH 6.75 to 8.70, electrical conductivity 540 to 855 μS/cm, total dissolved solids 325.46 to 515.23 ppm and dissolved oxygen 1.50 to 5.64 mg/L which are within the WHO guidelines for drinking water quality. The water samples were analysed for 30 elements (aluminium, iron, magnesium, manganese, silicon, zinc, molybdenum, titanium, chromium, nickel, tungsten, silver, arsenic, boron, barium, beryllium, cadmium, cobalt, copper, gallium, mercury, lanthanum, niobium, neodymium, lead, selenium, samarium, tin, vanadium and zirconium) by using inductively coupled plasma atomic emission spectroscopy. The organic contamination was detected in terms of most probable number (MPN) of faecal coliforms. Overall, elemental levels were lower than the recommended values but three water bores (B-1, B-6, B-7) had higher values of iron (1.6, 2.206, 0.65 ppm), two water bores (B-1, B-6) had higher values of aluminium (0.95, 1.92 ppm), respectively, and molybdenum was higher by 0.01 ppm only in one water bore (B-11). The total number of coliforms present in water samples was found to be within the prescribed limit of the WHO except for 5 out of 11 bore water samples (B-2, B-3, B-4, B-8, B-11), which were found in the range 5-35 MPN/100 mL, a consequence of infiltration of contaminated water (sewage) through cross connection, leakage points and back siphoning.

Development of water quality criteria of ammonia for protecting aquatic life in freshwater using species sensitivity distribution method.

PubMed

Park, Tae-Jin; Lee, Jong-Hyeon; Lee, Myung-Sung; Park, Chang-Hee; Lee, Chang-Hoon; Moon, Seong-Dae; Chung, Jiwoong; Cui, Rongxue; An, Youn-Joo; Yeom, Dong-Hyuk; Lee, Soo-Hyung; Lee, Jae-Kwan; Zoh, Kyung-Duk

2018-09-01

Ammonia is deemed one of the most important pollutants in the freshwater environment because of its highly toxic nature and ubiquity in surface water. This study thus aims to derive the criteria for ammonia in freshwater to protect aquatic life because there are no water quality criteria for ammonia in Korea. Short-term lethal tests were conducted to perform the species sensitivity distribution (SSD) method. This method is widely used in ecological risk assessment to determine the chemical concentrations to protect aquatic species. Based on the species sensitivity distribution method using Korean indigenous aquatic biota, the hazardous concentration for 5% of biological species (HC 5 ) value calculated in this study was 44mg/L as total ammonia nitrogen (TAN). The value of the assessment factor was set at 2. Consequently, the criteria for ammonia were derived as 22mg/L at pH7 and 20°C. When the derived value was applied to the monitoring data nationwide, 0.51%, 0.09%, 0.18%, 0.20%, and 0.35% of the monitoring sites in Han River, Nakdong River, Geum River, Youngsan River, and lakes throughout the nation, respectively, exceeded this criteria. The Ministry of Environment in Korea has been considering introducing water quality standard of ammonia for protecting aquatic life. Therefore, our results can provide the basis for introducing the ammonia standard in Korea. Copyright © 2018 Elsevier B.V. All rights reserved.

Cadmium and lead accumulations and agronomic quality of a newly bred pollution-safe cultivar (PSC) of water spinach.

PubMed

Huang, Ying-Ying; Mu, Yang-Xiu; He, Chun-Tao; Fu, Hui-Ling; Wang, Xue-Song; Gong, Fei-Yue; Yang, Zhong-Yi

2018-04-01

Breeding for pollution-safe cultivars (PSCs) can reduce pollutant accumulation in crops. However, the PSC breeding would face the risk of nutritional quality reduction, which is usually ignored in conventional breeding programs targeting to increase crop yield or nutritional quality. Thus, the doubt whether the risk would exist has to be clarified for supporting the PSC breeding. In the present study, a newly bred Cd/Pb-PSC of water spinach (Ipomoea aquatic Forsk.) and its parents (QLQ with low-Cd/Pb accumulation ability and T308 with high yield) of water spinach were employed to clarify the above-mentioned issue. Yields, and concentrations of Cd, Pb, nitrite, and organic and inorganic nutrients in shoots of the three experimental lines were determined. There were no significant differences in Cd/Pb concentration between the new PSC and QLQ, in nitrite content between the new PSC and its two parents and in yield between the new PSC and T308. It is decisively significant that shoot concentrations of organic and inorganic nutrients in the Cd/Pb-PSC were as high as those in one of its parents. It is affirmed that the breeding operations (crossing and consequently continuous selfing) for lowering Cd/Pb accumulation capacity of water spinach would not lower the nutritional values of the obtained Cd/Pb-PSCs from the breeding, which should be a pillar that supports the feasibility to minimize Cd/Pb pollution in vegetables using PSC-breeding method.

Influence of the Pearl River estuary and vertical mixing in Victoria Harbor on water quality in relation to eutrophication impacts in Hong Kong waters.

PubMed

Yin, Kedong; Harrison, Paul J

2007-06-01

This study presents water quality parameters such as nutrients, phytoplankton biomass and dissolved oxygen based on 11 years of water quality data in Victoria Harbor and examined how the Pearl River estuary discharge in summer and year round sewage discharge influenced these parameters. Nutrients in Victoria Harbor were strongly influenced by both the Pearl River and sewage effluent, as indicated by the high NO(3) inputs from the Pearl River in summer and higher NH(4) and PO(4) in Victoria Harbor than both its sides. N:P ratios were low in the dry season, but increased to >16:1 in the wet season, suggesting that P is potentially the most limiting nutrient in this area during the critical period in the summer. Although there were generally high nutrients, the phytoplankton biomass was not as high as one would expect in Victoria Harbor. In fact, there were high concentrations of chl near the bottom well below the photic zone. Salinity near the bottom was lower in Victoria Harbor than at the two entrances to Victoria Harbor, suggesting strong vertical mixing within Victoria Harbor. Therefore, strong vertical mixing and horizontal advection appear to play an important role in significantly reducing eutrophication impacts in Victoria Harbor. Consequently, dissolved oxygen near the bottom was low in summer, but only occasionally dipped to 2 mgL(-1) despite the high organic loading from sewage effluent.

Selecting Metrics for Sustainable Bioenergy Feedstocks

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

Dale, Virginia H; Kline, Keith L; Mulholland, Patrick J

Key decisions about land-use practices and dynamics in biofuel systems affect the long-term sustainability of biofuels. Choices about what crops are grown and how are they planted, fertilized, and harvested determine the effects of biofuels on native plant diversity, competition with food crops, and water and air quality. Those decisions also affect economic viability since the distance that biofuels must be transported has a large effect on the market cost of biofuels. The components of a landscape approach include environmental and socioeconomic conditions and the bioenergy features [type of fuel, plants species, management practices (e.g., fertilizer and pesticide applications), typemore » and location of production facilities] and ecological and biogeochemical feedbacks. Significantly, while water (availability and quality) emerges as one of the most limiting factors to sustainability of bioenergy feedstocks, the linkage between water and bioenergy choices for land use and management on medium and large scales is poorly quantified. Metrics that quantify environmental and socioeconomic changes in land use and landscape dynamics provide a way to measure and communicate the influence of alternative bioenergy choices on water quality and other components of the environment. Cultivation of switchgrass could have both positive and negative environmental effects, depending on where it is planted and what vegetation it replaces. Among the most important environmental effects are changes in the flow regimes of streams (peak storm flows, base flows during the growing season) and changes in stream water quality (sediment, nutrients, and pesticides). Unfortunately, there have been few controlled studies that provide sufficient data to evaluate the hydrological and water quality impacts of conversion to switchgrass. In particular, there is a need for experimental studies that use the small watershed approach to evaluate the effects of growing a perennial plant as a biomass crop. Small watershed studies have been used for several decades to identify effects of vegetation type, disturbance, and land use and agriculture practices on hydrology and water quality. An ideal experimental design to determine the effects of conversion to switchgrass on surface water hydrology and quality would involve (1) small catchment (5-20 ha) drained by a perennial or ephemeral stream, (2) crop treatments including conversion from row crops to switchgrass; pasture to switchgrass (other likely scenarios); controls (no change in vegetation), (3) treatments to compare different levels of fertilization and pesticide application, (4) riparian treatments to compare riparian buffers with alternative cover types, and a treatment with no buffer, and (5) 3-4 replicates of each treatment or BACI (before-after, control-intervention) design for unreplicated treatments (ideally with several years of measurements prior to the imposition of treatments for BACI design). Hydrologic measurements would include soil moisture patterns with depth and over time; nitrogen and phosphorus chemistry; soil solution chemistry - major anions and cations, inorganic and organic forms of carbon, nitrogen and phosphorus; precipitation amount and chemical deposition; stream discharge; and streamwater chemistry. These water quality metrics would need to be put into context of the other environmental and social conditions that are altered by growth of bioenergy feedstocks. These conditions include farm profits and yield of food and fuel, carbon storage and release, and a variety of ecosystem services such as enhanced biodiversity and pollinator services. Innovations in landscape design for bioenergy feedstocks take into account environmental and socioeconomic dynamics and consequences with consideration of alternative bioenergy regimes and policies. The ideal design would be scale-sensitive so that economic, social, and environmental constraints can be measured via metrics applicable at relevant scales. To develop a landscape design, land managers must consider (1) what are the environmental impacts on water and air quality, carbon sequestration, and native plants and animals and their habitats; (2) what is the appropriate spatial and temporal scales at which to examine environmental effects, and (3) how can potential tradeoffs in environmental costs and benefits be considered. Tradeoffs exist across space and time among the economic, ecological, and social consequences of alternative choices. For example, the implications of increased biofuel production from corn at a local scale may be to increase pesticide use, which could negatively affect human health. At a regional scale, nutrient flux may increase and thus degrade water quality. At the scale of the Mississippi River watershed (48% of the U.S.), production may increase the hypoxia zone in the Gulf of Mexico and cause decline of shrimp harvest in the region.« less

Approaches for integrated assessment of ecological and eutrophication status of surface waters in Nordic Countries.

PubMed

Andersen, Jesper H; Aroviita, Jukka; Carstensen, Jacob; Friberg, Nikolai; Johnson, Richard K; Kauppila, Pirkko; Lindegarth, Mats; Murray, Ciarán; Norling, Karl

2016-10-01

We review approaches and tools currently used in Nordic countries (Denmark, Finland, Norway and Sweden) for integrated assessment of 'ecological status' sensu the EU Water Framework Directive as well as assessment of 'eutrophication status' in coastal and marine waters. Integration principles for combining indicators within biological quality elements (BQEs) and combining BQEs into a final-integrated assessment are discussed. Specific focus has been put on combining different types of information into indices, since several methods are currently employed. As a consequence of the variety of methods used, comparisons across both BQEs and water categories (river, lakes and coastal waters) can be difficult. Based on our analyses, we conclude that some principles and methods for integration can be critical and that a harmonised approach should be developed. Further, we conclude that the integration principles applied within BQEs are critical and in need of harmonisation if we want a better understanding of potential transition in ecological status between surface water types, e.g. when riverine water enters a downstream lake or coastal water body.

Spatial Optimization of Cropping Pattern in an Agricultural Watershed for Food and Biofuel Production with Minimum Downstream Pollution

NASA Astrophysics Data System (ADS)

Pv, F.; Sudheer, K.; Chaubey, I.; RAJ, C.; Her, Y.

2013-05-01

Biofuel is considered to be a viable alternative to meet the increasing fuel demand, and therefore many countries are promoting agricultural activities that help increase production of raw material for biofuel production. Mostly, the biofuel is produced from grain based crops such as Corn, and it apparently create a shortage in food grains. Consequently, there have been regulations to limit the ethanol production from grains, and to use cellulosic crops as raw material for biofuel production. However, cultivation of such cellulosic crops may have different effects on water quality in the watershed. Corn stover, one of the potential cellulosic materials, when removed from the agricultural field for biofuel production, causes a decrease in the organic nutrients in the field. This results in increased use of pesticides and fertilizers which in turn affect the downstream water quality due to leaching of the chemicals. On the contrary, planting less fertilizer-intensive cellulosic crops, like Switch Grass and Miscanthus, is expected to reduce the pollutant loadings from the watershed. Therefore, an ecologically viable land use scenario would be a mixed cropping of grain crops and cellulosic crops, that meet the demand for food and biofuel without compromising on the downstream water quality. Such cropping pattern can be arrived through a simulation-optimization framework. Mathematical models can be employed to evaluate various management scenarios related to crop production and to assess its impact on water quality. Soil and Water Assessment Tool (SWAT) model is one of the most widely used models in this context. SWAT can simulate the water and nutrient cycles, and also quantify the long-term impacts of land management practices, in a watershed. This model can therefore help take decisions regarding the type of cropping and management practices to be adopted in the watershed such that the water quality in the rivers is maintained at acceptable level. In this study, it is proposed to link SWAT model with an optimization algorithm, whose objective is to identify the optimal cropping pattern that results in maximum biomass production for biofuel generation as well as a minimum guaranteed amount of grain production. The optimal allocation ensures that the downstream water quality in the river is within a desirable limit. The study employed probabilistic information in order to address the uncertainty in model simulations. The residual variance of the model is used to transform the deterministic simulations in to probabilistic information. The proposed framework is illustrated using data pertaining to an agricultural watershed in the USA. The preliminary results of the study are encouraging and suggest that an appropriate combination of Corn, Soyabean, Miscanthus, Switch Grass and Pasture land can be arrived at through the developed framework. The placement of Miscanthus and Switch Grass in the watershed help improve the downstream water quality, while Corn and Soyabean makes it deteriorated. The spatial allocation of these crops therefore certainly plays a major role in the downstream water quality.

Balancing water scarcity and quality for sustainable irrigated agriculture

NASA Astrophysics Data System (ADS)

Assouline, Shmuel; Russo, David; Silber, Avner; Or, Dani

2015-05-01

The challenge of meeting the projected doubling of global demand for food by 2050 is monumental. It is further exacerbated by the limited prospects for land expansion and rapidly dwindling water resources. A promising strategy for increasing crop yields per unit land requires the expansion of irrigated agriculture and the harnessing of water sources previously considered "marginal" (saline, treated effluent, and desalinated water). Such an expansion, however, must carefully consider potential long-term risks on soil hydroecological functioning. The study provides critical analyses of use of marginal water and management approaches to map out potential risks. Long-term application of treated effluent (TE) for irrigation has shown adverse impacts on soil transport properties, and introduces certain health risks due to the persistent exposure of soil biota to anthropogenic compounds (e.g., promoting antibiotic resistance). The availability of desalinated water (DS) for irrigation expands management options and improves yields while reducing irrigation amounts and salt loading into the soil. Quantitative models are used to delineate trends associated with long-term use of TE and DS considering agricultural, hydrological, and environmental aspects. The primary challenges to the sustainability of agroecosystems lies with the hazards of saline and sodic conditions, and the unintended consequences on soil hydroecological functioning. Multidisciplinary approaches that combine new scientific knowhow with legislative, economic, and societal tools are required to ensure safe and sustainable use of water resources of different qualities. The new scientific knowhow should provide quantitative models for integrating key biophysical processes with ecological interactions at appropriate spatial and temporal scales.

A GIS-based assessment of groundwater suitability for irrigation purposes in flat areas of the wet Pampa plain, Argentina.

PubMed

Romanelli, Asunción; Lima, María Lourdes; Quiroz Londoño, Orlando Mauricio; Martínez, Daniel Emilio; Massone, Héctor Enrique

2012-09-01

The Pampa in Argentina is a large plain with a quite obvious dependence on agriculture, water availability and its quality. It is a sensitive environment due to weather changes and slope variations. Supplementary irrigation is a useful practice for compensating the production in the zone. However, potential negative impacts of this type of irrigation in salinization and sodification of soils are evident. Most conventional methodologies for assessing water irrigation quality have difficulties in their application in the region because they do not adjust to the defined assumptions for them. Consequently, a new GIS-based methodology integrating multiparametric data was proposed for evaluating and delineating groundwater suitability zones for irrigation purposes in flat areas. Hydrogeological surveys including water level measurements, groundwater samples for chemical analysis and electrical conductivity (EC) measurements were performed. The combination of EC, sodium adsorption ratio, residual sodium carbonate, slopes and hydraulic gradient parameters generated an irrigation water index (IWI). With the integration of the IWI 1 to 3 classes (categories of suitable waters for irrigation) and the aquifer thickness the restricted irrigation water index (RIWI) was obtained. The IWI's index application showed that 61.3 % of the area has "Very high" to "Moderate" potential for irrigation, while the 31.4 % of it has unsuitable waters. Approximately, 46 % of the tested area has high suitability for irrigation and moderate groundwater availability. This proposed methodology has advantages over traditional methods because it allows for better discrimination in homogeneous areas.

Case study on rehabilitation of a polluted urban water body in Yangtze River Basin.

PubMed

Wu, Juan; Cheng, Shuiping; Li, Zhu; Guo, Weijie; Zhong, Fei; Yin, Daqiang

2013-10-01

In the past three decades, the fast development of economy and urbanization has caused increasingly severe pollutions of urban water bodies in China. Consequently, eutrophication and deterioration of aquatic ecosystem, which is especially significant for aquatic vegetation, inevitably became a pervasive problem across the Yangtze River Basin. To rehabilitate the degraded urban water bodies, vegetation replanting is an important issue to improve water quality and to rehabilitate ecosystem. As a case study, a representative polluted urban river, Nanfeihe River, in Hefei City, Anhui Province, was chosen to be a rehabilitation target. In October 2009 and May 2010, 13 species of indigenous and prevalent macrophytes, including seven species emergent, one species floating leaved, and five species submersed macrophytes, were planted along the bank slopes and in the river. Through 1.5 years' replanting practice, the water quality and biodiversity of the river had been improved. The concentrations of total nitrogen (TN), total phosphorus (TP), and ammonia nitrogen (NH4 (+)-N) declined by 46.0, 39.5, and 60.4 %, respectively. The species of macrophytes increased from 14 to 60, and the biodiversity of phytoplankton rose significantly in the river (p<0.05). The biomasses of zooplankton and benthos were also improved after the vegetation replanting. The study confirmed that vegetation replanting could alleviate the increasing water pollution and rehabilitate the degraded aquatic ecosystem. The case study would be an example for polluted urban waters restoration in the middle-downstream area of Yangtze River Base.

Impacts of climate and land use changes on regional nutrient export in the South Saskatchewan River catchment

NASA Astrophysics Data System (ADS)

Morales-Marin, L. A.; Wheater, H. S.; Lindenschmidt, K. E.

2016-12-01

Climate and land use changes modify the physical functioning of river catchments and, in particular, influence the transport of nutrients from land to water. In large-scale catchments, where a variety of climates, topographies, soil types and land uses co-exist to form a highly heterogeneous environment, a more complex nutrient dynamic is imposed by climate and land use changes. This is the case of the South Saskatchewan River (SSR) that, along with the North Saskatchewan River, forms the largest river system in western Canada. In the past years changes in the land use and new industrial developments in the SSR area have heightened serious concerns about the future of water quality in the catchment and downstream waters. Agricultural activities have increased the supply of manure and fertilizer for cropping. Oil and gas exploitation has also increased the risk of surface water and groundwater contamination. The rapid population growth not only leads to increments in water consumption and wastewater, but in the construction of roads, railways and the expansion of new urban developments that impose hydraulic controls on the catchment hydrology and therefore the sediment and nutrient transport. Consequences of the actual anthropogenic changes have been notorious in reservoirs where algal blooms and signs of eutrophication have become common during certain times of the year. Although environmental agencies are constantly improving the mechanisms to reduce nutrient export into the river and ensure safe water quality standards, further research is needed in order to identify major nutrient sources and quantify nutrient export and also, to assess how nutrients are going to vary as a result of future climate and land use change scenarios. The SPAtially Referenced Regression On Watershed (SPARROW) model is therefore implemented to assess water quality regionally, in order to describe spatial and temporal patterns to identify those factors and processes that affect water quality. Climate and land uses change scenarios are incorporated into the model to explain how nutrient export will vary across the catchment in 30, 60 and 90 years from now. Uncertainty of nutrient predictions is also assesses in order to determine the degree of reliability of the estimates.

Impacts of climate and land use changes on regional nutrient export in the South Saskatchewan River catchment

NASA Astrophysics Data System (ADS)

Morales-Marin, L. A.; Wheater, H. S.; Lindenschmidt, K. E.

2015-12-01

Climate and land use changes modify the physical functioning of river catchments and, in particular, influence the transport of nutrients from land to water. In large-scale catchments, where a variety of climates, topographies, soil types and land uses co-exist to form a highly heterogeneous environment, a more complex nutrient dynamic is imposed by climate and land use changes. This is the case of the South Saskatchewan River (SSR) that, along with the North Saskatchewan River, forms the largest river system in western Canada. In the past years changes in the land use and new industrial developments in the SSR area have heightened serious concerns about the future of water quality in the catchment and downstream waters. Agricultural activities have increased the supply of manure and fertilizer for cropping. Oil and gas exploitation has also increased the risk of surface water and groundwater contamination. The rapid population growth not only leads to increments in water consumption and wastewater, but in the construction of roads, railways and the expansion of new urban developments that impose hydraulic controls on the catchment hydrology and therefore the sediment and nutrient transport. Consequences of the actual anthropogenic changes have been notorious in reservoirs where algal blooms and signs of eutrophication have become common during certain times of the year. Although environmental agencies are constantly improving the mechanisms to reduce nutrient export into the river and ensure safe water quality standards, further research is needed in order to identify major nutrient sources and quantify nutrient export and also, to assess how nutrients are going to vary as a result of future climate and land use change scenarios. The SPAtially Referenced Regression On Watershed (SPARROW) model is therefore implemented to assess water quality regionally, in order to describe spatial and temporal patterns to identify those factors and processes that affect water quality. Climate and land uses change scenarios are incorporated into the model to explain how nutrient export will vary across the catchment in 30, 60 and 90 years from now. Uncertainty of nutrient predictions is also assesses in order to determine the degree of reliability of the estimates.

Troubled Waters: Navigating Unintended Consequences of Health Information Technology.

PubMed

Lehmann, C U; Séroussi, B; Jaulent, M-C

2016-11-10

To provide an introduction to the 2016 IMIA Yearbook of Medical Informatics by the editors. We present a brief overview of the 2016 special topic "Unintended consequences of Health IT: new problems, new solutions", we review our choice of special topic section editors, and discuss the transitions in the editorial team for next year. This edition of the Yearbook acknowledges the fact that implementation and use of Health Information Technology (HIT) may result in unintended consequences, which may lead to both adverse and sometimes beneficial outcomes. However to date, in the literature, undesired outcomes are emphasized with a focus on the complex causes and the many sources that may generate them. The growing awareness of the importance of HIT's unintended consequences and their increasing documentation reflect a wider acceptance of HIT by users (more use generating more consequences) and and a new type of users (a shift from early adopters to late adopters and laggards), whith great expectations regarding the improvement of care quality through HIT solutions. Different points of view on new problems and new solutions of unintended consequences of Health IT are presented through the keynote paper, survey papers, and the working group contributions. The regular 2016 issue of the IMIA yearbook focuses on new unintended consequences of Health IT - brought on by wider adoption and different types of users as well as solutions to addressing them.

Water Availability for the Western United States - Key Scientific Challenges

USGS Publications Warehouse

Anderson, Mark Theodore; Woosley, Lloyd H.

2005-01-01

In the Western United States, the availability of water has become a serious concern for many communities and rural areas. Near population centers, surface-water supplies are fully appropriated, and many communities are dependent upon ground water drawn from storage, which is an unsustainable strategy. Water of acceptable quality is increasingly hard to find because local sources are allocated to prior uses, depleted by overpumping, or diminished by drought stress. Some of the inherent characteristics of the West add complexity to the task of securing water supplies. The Western States, including the arid Southwest, have the most rapid population growth in the United States. The climate varies widely in the West, but it is best known for its low precipitation, aridity, and drought. There is evidence that the climate is warming, which will have consequences for Western water supplies, such as increased minimum streamflow and earlier snowmelt events in snow-dominated basins. The potential for departures from average climatic conditions threatens to disrupt society and local to regional economies. The appropriative rights doctrine governs the management of water in most Western States, although some aspects of the riparian doctrine are being incorporated. The 'use it or lose it' provisions of Western water law discourage conservation and make the reallocation of water to instream environmental uses more difficult. The hydrologic sciences have defined the interconnectedness of ground water and surface water, yet these resources are still administered separately by most States. The definition of water availability has been expanded to include sustaining riparian ecosystems and individual endangered species, which are disproportionately represented in the Western States. Federal reserved rights, common in the West because of the large amount of Federal land, exist with quite senior priority dates whether or not water is currently being used. A major challenge for water users in the West is that these reserved rights may supersede other existing users. The minimum amount of water required, however, to sustain native peoples, a riparian system, or an endangered species eventually will need to be known in order to manage the available water supply. Periodic inventory and assessment of the amounts and trends of water available in surface water and ground water are needed to support water management. There is a widespread perception that the amount of available water is diminishing with time. This and other perceptions about water availability should be replaced by objective data and analysis. Some data are presented here for the major Western rivers that show that flows are not decreasing in most streams and rivers in the West. Systematic information is lacking to make broad assessments of ground-water availability, but available data for specific aquifers indicate that these aquifers are being depleted, especially near population centers. The complexity added to the issue of Western water availability by these and other factors gives rise to a significant role of science. Science has played a role in support of Western water development from the beginning, and the role has evolved and changed over time as society's values have changed. In this report, the role of science is discussed in three phases: (1) development and construction, (2) consequences and environmental awareness, and (3) sustainability. The development and construction phase includes some historical accounting of water development in the West and shows how some precedents set in those early days are still applied today. Science has played an important role in the second phase by objectively pointing out the consequences of this development and construction phase, such as the effects from converting rivers to reservoirs, the effects of ground-water pumping on surface water in streams, land-surface subsidence, and the changes in water quality brought about by the dispo

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

Apps, John A.; Wilkin, Richard T.

This report contains a series of tables summarizing the thermodynamic properties of aqueous carbonate complexes and solid carbonate phases of the following elements: arsenic (As), barium (Ba), cadmium (Cd), chromium (Cr), cobalt (Co), copper (Cu), iron (Fe), lead (Pb), manganese (Mn), mercury (Hg), nickel (Ni) thallium (Tl), uranium (U) and zinc (Zn). Most of these elements are potentially hazardous as defined by extant primary drinking water standards of the United States Environmental Protection Agency (EPA). The remainder are not considered hazardous, but are either listed by EPA under secondary standards, or because they can adversely affect drinking water quality. Additionalmore » tables are included giving the thermodynamic properties for carbonates of the alkali metal and alkali earth elements, sodium (Na), potassium (K), magnesium (Mg), calcium (Ca), and strontium (Sr), because of their value in developing correlative models to estimate the thermodynamic properties of carbonate minerals for which no such data currently exist. The purpose in creating the tables in this report is to provide future investigators with a convenient source for selecting and tracing the sources of thermodynamic data of the above listed elements for use in modeling their geochemical behavior in “underground sources of drinking water” (USDW). The incentive for doing so lies with a heightened concern over the potential consequences of the proposed capture and storage of carbon dioxide (CO2) generated by fossil fuel fired power plants in deep subsurface reservoirs. If CO2 were to leak from such reservoirs, it could migrate upward and contaminate USDWs with undesirable, but undetermined, consequences to water quality. The EPA, Office of Research and Development, through an Interagency Agreement with the U.S. Department of Energy at the Lawrence Berkeley National Laboratory, funded the preparation of this report.« less

Water quality assessment of a small peri-urban river using low and high frequency monitoring.

PubMed

Ivanovsky, A; Criquet, J; Dumoulin, D; Alary, C; Prygiel, J; Duponchel, L; Billon, G

2016-05-18

The biogeochemical behaviors of small rivers that pass through suburban areas are difficult to understand because of the multi-origin inputs that can modify their behavior. In this context, a monitoring strategy has been designed for the Marque River, located in Lille Metropolitan area of northern France, that includes both low-frequency monitoring over a one-year period (monthly sampling) and high frequency monitoring (measurements every 10 minutes) in spring and summer. Several environmental and chemical parameters are evaluated including rainfall events, river flow, temperature, dissolved oxygen, turbidity, conductivity, nutritive salts and dissolved organic matter. Our results from the Marque River show that (i) it is impacted by both urban and agricultural inputs, and as a consequence, the concentrations of phosphate and inorganic nitrogen have degraded the water quality; (ii) the classic photosynthesis/respiration processes are disrupted by the inputs of organic matter and nutritive salts; (iii) during dry periods, the urban sewage inputs (treated or not) are more important during the day, as indicated by higher river flows and maximal concentrations of ammonium; (iv) phosphate concentrations depend on oxygen contents in the river; (v) high nutrient concentrations result in eutrophication of the Marque River with lower pH and oxygen concentrations in summer. During rainfalls, additional inputs of ammonium, biodegradable organic matter as well as sediment resuspension result in anoxic events; and finally (vi) concentrations of nitrate are approximately constant over the year, except in winter when higher inputs can be recorded. Having better identified the processes responsible for the observed water quality, a more informed remediation effort can be put forward to move this suburban river to a good status of water quality.

Microbial contamination of water intended for milk container washing in smallholder dairy farming and milk retailing houses in southern Ethiopia.

PubMed

Amenu, Kebede; Shitu, Desalew; Abera, Mesele

2016-01-01

The water used during handling and processing of milk products can be potential sources of microbial contamination with possible negative consequences on food safety. Especially, the water used in keeping the hygiene of milking and milk storage utensils is crucial to keep the quality and safety of the products. Therefore, the current study was designed to assess the bacteriological quality of water used for cleaning milking and milk storage equipment in smallholder dairy production in Hawassa and its surroundings. A total of 79 water samples were collected: 26 from milk collecting houses in Hawassa and 53 from selected smallholder dairy farms (Hawassa = 14, Arsi Negele = 29 and Yirgalem = 10). Out of the total samples, 18 samples were collected directly from pipe and 61 from storage containers (46 from narrow opening and 15 from wide opening containers). The overall prevalence of E. coli exceeding zero CFU/ml was 39.2 %. From analyzed samples, high prevalence of positive samples for E. coli was found in water samples taken from wide opening containers (66.7 %). A number of bacteria were isolated and presumptively identified which include Bacillus sp. 6.3 % (n = 5), Citrobacter sp. 1.3 %(n = 1), E. coli 39.2 % (n = 31), Enterobacter sp. 2.5 % (n = 2), Klebisella sp. 7.6 % (n = 6), Micrococcus sp. 6.3 % (n = 5), Pseudomonas sp. 6.3 % (n = 5), Staphylococcus aureus 6.3 % (n = 5), Staphylococcus epidermidis 13.9 % (n = 11) and Streptococcus sp. 1.3 % (n = 1). The bacteriological quality of water especially, water stored in household storage containers in present study area was found to be contaminated with different bacteria indicating potential food safety problem and health risk to the society. In this respect, people handling water should be educated on its proper handling and the risk of contamination during storage. To minimize contamination, materials with narrow mouth and lid should be used. Further study is recommended on the relationship between the bacteriological quality of water and the behavior of water users.

Mediterranean water resources in a global change scenario

NASA Astrophysics Data System (ADS)

García-Ruiz, José M.; López-Moreno, J. Ignacio; Vicente-Serrano, Sergio M.; Lasanta–Martínez, Teodoro; Beguería, Santiago

2011-04-01

Mediterranean areas of both southern Europe and North Africa are subject to dramatic changes that will affect the sustainability, quantity, quality, and management of water resources. Most climate models forecast an increase in temperature and a decrease in precipitation at the end of the 21st century. This will enhance stress on natural forests and shrubs, and will result in more water consumption, evapotranspiration, and probably interception, which will affect the surface water balance and the partitioning of precipitation between evapotranspiration, runoff, and groundwater flow. As a consequence, soil water content will decline, saturation conditions will be increasingly rare and restricted to periods in winter and spring, and snow accumulation and melting will change, especially in the mid-mountain areas. Future land management will be characterized by forest and shrub expansion in most Mediterranean mountain areas, as a consequence of farmland and grazing abandonment, with increasing human pressure localized only in some places (ski resort and urbanized of valley floors). In the lowlands, particularly in the coastal fringe, increasing water demand will occur as a consequence of expansion of irrigated lands, as well as the growth of urban and industrial areas, and tourist resorts. Future scenarios for water resources in the Mediterranean region suggest (1) a progressive decline in the average streamflow (already observed in many rivers since the 1980s), including a decline in the frequency and magnitude of the most frequent floods due to the expansion of forests; (2) changes in important river regime characteristics, including an earlier decline in high flows from snowmelt in spring, an intensification of low flows in summer, and more irregular discharges in winter; (3) changes in reservoir inputs and management, including lower available discharges from dams to meet the water demand from irrigated and urban areas. Most reservoirs in mountain areas will be subject to increasing water resource uncertainty, because of the reduced influence of snow accumulation and snowmelt processes. Besides, reservoir capacity is naturally reduced due to increasing sedimentation and, in some cases, is also decreased to improve the safety control of floods, leading to a reduction in efficiency for agriculture. And (4) hydrological and population changes in coastal areas, particularly in the delta zones, affected by water depletion, groundwater reduction and saline water intrusion. These scenarios enhance the necessity of improving water management, water prizing and water recycling policies, in order to ensure water supply and to reduce tensions among regions and countries.

Watershed safety and quality control by safety threshold method

NASA Astrophysics Data System (ADS)

Da-Wei Tsai, David; Mengjung Chou, Caroline; Ramaraj, Rameshprabu; Liu, Wen-Cheng; Honglay Chen, Paris

2014-05-01

Taiwan was warned as one of the most dangerous countries by IPCC and the World Bank. In such an exceptional and perilous island, we would like to launch the strategic research of land-use management on the catastrophe prevention and environmental protection. This study used the watershed management by "Safety Threshold Method" to restore and to prevent the disasters and pollution on island. For the deluge prevention, this study applied the restoration strategy to reduce total runoff which was equilibrium to 59.4% of the infiltration each year. For the sediment management, safety threshold management could reduce the sediment below the equilibrium of the natural sediment cycle. In the water quality issues, the best strategies exhibited the significant total load reductions of 10% in carbon (BOD5), 15% in nitrogen (nitrate) and 9% in phosphorus (TP). We found out the water quality could meet the BOD target by the 50% peak reduction with management. All the simulations demonstrated the safety threshold method was helpful to control the loadings within the safe range of disasters and environmental quality. Moreover, from the historical data of whole island, the past deforestation policy and the mistake economic projects were the prime culprits. Consequently, this study showed a practical method to manage both the disasters and pollution in a watershed scale by the land-use management.

Evaluating the human impact on groundwater quality discharging into a coastal reef lagoon

NASA Astrophysics Data System (ADS)

Rebolledo-Vieyra, M.; Hernandez-Terrones, L.; Soto, M.; Lecossec, A.; Monroy-Rios, E.

2008-12-01

The Eastern coast of the Yucatan Peninsula has the fastest growth rate in Mexico and groundwater is the only source of drinking water in the region. The consequences of the lack of proper infrastructure to collect and treat wastewater and the impact of human activities on the quality of groundwater are addressed. The groundwater in the coastal aquifer of Quintana Roo (SE Mexico) discharges directly into the ocean. In addition, the coral reef of the Eastern Yucatan Peninsula is part of the Mesoamerican Coral Reef System, one of the largest in the world. The interaction of the reef-lagoon hydraulics with the coastal aquifer of Puerto Morelos (NE Yucatan Peninsula), and a major input of NH4, SO4, SiO2, as a consequence of the use of septic tanks and the lack of modern wastewater treatment plants are presented. No seasonal parameters differences were observed, suggesting that groundwater composition reaching the reef lagoon is not changing seasonally. A conceptual model of the coastal aquifer was developed, in order to explain how the human activities are impacting directly on the groundwater quality that, potentially, will have a direct impact on the coral reef. The protection and conservation of coral reefs must be directly related with a policy of sound management of coastal aquifers and wastewater treatment.

Modeling drivers of phosphorus loads in Chesapeake Bay tributaries and inferences about long-term change

USGS Publications Warehouse

Ryberg, Karen R.; Blomquist, Joel; Sprague, Lori A.; Sekellick, Andrew J.; Keisman, Jennifer

2018-01-01

Causal attribution of changes in water quality often consists of correlation, qualitative reasoning, listing references to the work of others, or speculation. To better support statements of attribution for water-quality trends, structural equation modeling was used to model the causal factors of total phosphorus loads in the Chesapeake Bay watershed. By transforming, scaling, and standardizing variables, grouping similar sites, grouping some causal factors into latent variable models, and using methods that correct for assumption violations, we developed a structural equation model to show how causal factors interact to produce total phosphorus loads. Climate (in the form of annual total precipitation and the Palmer Hydrologic Drought Index) and anthropogenic inputs are the major drivers of total phosphorus load in the Chesapeake Bay watershed. Increasing runoff due to natural climate variability is offsetting purposeful management actions that are otherwise decreasing phosphorus loading; consequently, management actions may need to be reexamined to achieve target reductions in the face of climate variability.

Toxicity assessment of the water used for human consumption from the Cameron/Tuba City abandoned uranium mining area prior/after the combined electrochemical treatment/advanced oxidation.

PubMed

Gajski, Goran; Oreščanin, Višnja; Gerić, Marko; Kollar, Robert; Lovrenčić Mikelić, Ivanka; Garaj-Vrhovac, Vera

2015-01-01

The purpose of this work was detailed physicochemical, radiological, and toxicological characterization of the composite sample of water intended for human consumption in the Cameron/Tuba City abandoned uranium mining area before and after a combined electrochemical/advanced oxidation treatment. Toxicological characterization was conducted on human lymphocytes using a battery of bioassays. On the bases of the tested parameters, it could be concluded that water used for drinking from the tested water sources must be strictly forbidden for human and/or animal consumption since it is extremely cytogenotoxic, with high oxidative stress potential. A combined electrochemical treatment and posttreatment with ozone and UV light decreased the level of all physicochemical and radiological parameters below the regulated values. Consequently, the purified sample was neither cytotoxic nor genotoxic, indicating that the presented method could be used for the improvement of water quality from the sites highly contaminated with the mixture of heavy metals and radionuclides.

Comparison of E. coli, enterococci, and fecal coliform as indicators for brackish water quality assessment.

PubMed

Jin, Guang; Jeng, Huei-Wang; Bradford, Henry; Englande, A J

2004-01-01

Escherichia coli (E. coli), enterococci, and fecal coliform data were collected and compared as potential indicators for swimmablility assessment of a brackish waterbody (Lake Pontchartrain, Louisiana). These indicators were measured during lake background conditions, in stormwater runoff (before dilution with lake water), and in the outfall plume within the lake following storm events. Microbial indicator titers associated with suspended particles and lake-bottom sediments were also investigated. Overall reduction rate constants for fecal coliform, E. coli, and enterococci in lake water and sediment were measured and reported. Attachment of microbial indicators to suspended matter and subsequent sedimentation appeared to be a significant fate mechanism. A slower reduction rate of indicator organisms in sediment further suggested that bottom sediment may act as a reservoir for prolonging indicator organism survival and added concern of recontamination of overlaying waters due to potential solids resuspension. Results indicated that enterococci might be a more stable indicator than E. coli and fecal coliform and, consequently, a more conservative indicator under brackish water conditions.

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.

Enteric Viruses and Fecal Bacteria Indicators to Assess Groundwater Quality and Suitability for Irrigation

PubMed Central

De Giglio, Osvalda; Caggiano, Giuseppina; Bagordo, Francesco; Barbuti, Giovanna; Brigida, Silvia; Lugoli, Federica; Grassi, Tiziana; La Rosa, Giuseppina; Lucentini, Luca; Uricchio, Vito Felice; De Donno, Antonella; Montagna, Maria Teresa

2017-01-01

According to Italian Ministerial Decree No. 185 of 12 June 2003, water is considered suitable for irrigation if levels of fecal bacteria (i.e., Escherichia coli and Salmonella) are within certain parameters. The detection of other microorganisms is not required. The aim of this study is to determine the bacteriological quality of groundwater used for irrigation and the occurrence of enteric viruses (Norovirus, Enterovirus, Rotavirus, Hepatovirus A), and to compare the presence of viruses with the fecal bacteria indicators. A total of 182 wells was analyzed. Widespread fecal contamination of Apulian aquifers was detected (141 wells; 77.5%) by the presence of fecal bacteria (i.e., E. coli, Salmonella, total coliforms, and enterococci). Considering bacteria included in Ministerial Decree No. 185, the water from 35 (19.2%) wells was unsuitable for irrigation purposes. Among 147 wells with water considered suitable, Norovirus, Rotavirus, and Enterovirus were detected in 23 (15.6%) wells. No Hepatovirus A was isolated. Consequently, 58 wells (31.9%) posed a potential infectious risk for irrigation use. This study revealed the inadequacy of fecal bacteria indicators to predict the occurrence of viruses in groundwater and it is the first in Italy to describe the presence of human rotaviruses in well water used for irrigation. PMID:28538682

Hydration during intense exercise training.

PubMed

Maughan, R J; Meyer, N L

2013-01-01

Hydration status has profound effects on both physical and mental performance, and sports performance is thus critically affected. Both overhydration and underhydration - if sufficiently severe - will impair performance and pose a risk to health. Athletes may begin exercise in a hypohydrated state as a result of incomplete recovery from water loss induced in order to achieve a specific body mass target or due to incomplete recovery from a previous competition or training session. Dehydration will also develop in endurance exercise where fluid intake does not match water loss. The focus has generally been on training rather than on competition, but sweat loss and fluid replacement in training may have important implications. Hypohydration may impair training quality and may also increase stress levels. It is unclear whether this will have negative effects (reduced training quality, impaired immunity) or whether it will promote a greater adaptive response. Hypohydration and the consequent hyperthermia, however, can enhance the effectiveness of a heat acclimation program, resulting in improved endurance performance in warm and temperate environments. Drinking in training may be important in enhancing tolerance of the gut when athletes plan to drink in competition. The distribution of water between body water compartments may also be important in the initiation and promotion of cellular adaptations to the training stimulus. Copyright © 2013 Nestec Ltd., Vevey/S. Karger AG, Basel.

Steel Slag and Shredded Tires as Media for Blind Inlets to Improve Water Quality

NASA Astrophysics Data System (ADS)

Gonzalez, J. M.; Smith, D. R.; Livingston, S.

2015-12-01

Off-site transport of contaminants through surface runoff affects water quality. Blind inlets are proven conservation practices for reducing surface runoff, and consequently reducing nutrient loadings from small agricultural closed depressions to water bodies. Gravel is the most widely used blind inlet media to reduce flow, but not to sorb contaminants from the water. Readily available byproducts, such as steel slag and shredded tires, could be used as alternative media in blind inlets to sorb nutrients and pesticides from surface runoff. Sorption isotherms were performed to investigate the sorption capabilities of steel slag and shredded tires for phosphate and atrazine in electrolyte background solutions containing either 10 mM CaCl2 or KCl. Results of this research demonstrated that phosphate and atrazine were irreversibly sorbed by the steel slag and shredded tires. The steel slag increased the pH solution increased about 4 pH units after the sorption step; while the pH of the solution with shredded tires remained the same. Desorption of the phosphate and atrazine was low from the steel slag and shredded tires, respectively. Thus, the above results suggest that the steel slag and shredded tires can potentially be used as media to sorb phosphate and atrazine, respectively.

On-line monitoring of Escherichia coli in raw water at Oset drinking water treatment plant, Oslo (Norway).

PubMed

Tryland, Ingun; Eregno, Fasil Ejigu; Braathen, Henrik; Khalaf, Goran; Sjølander, Ingrid; Fossum, Marie

2015-02-04

The fully automated Colifast ALARM™ has been used for two years for daily monitoring of the presence/absence of Escherichia coli in 100 mL raw water at Oset drinking water treatment plant in Oslo, Norway. The raw water is extracted from 35 m depth from the Lake Maridalsvannet. E. coli was detected in 18% of the daily samples. In general, most samples positive for E. coli were observed during the autumn turnover periods, but even in some samples taken during warm and dry days in July, with stable temperature stratification in the lake, E. coli was detected. The daily samples gave useful additional information compared with the weekly routine samples about the hygienic raw water quality and the hygienic barrier efficiency of the lake under different weather conditions and seasons. The winter 2013/2014 was much warmer than the winter 2012/2013. The monitoring supported the hypothesis that warmer winters with shorter periods with ice cover on lakes, which may be a consequence of climate changes, may reduce the hygienic barrier efficiency in deep lakes used as drinking water sources.

Evaluation of the Influence of Specific Surface Treatments of RBA on a Set of Properties of Concrete

PubMed Central

Ondova, Marcela; Sicakova, Alena

2016-01-01

High water absorption of recycled brick aggregate (RBA) is one of the most discussed parameters in terms of its application in the production of concrete—its influence on the amount of mixing water and, hence, the quality of the concrete, is usually considered negative. In this paper, different methods of decreasing the absorption of RBA and, consequently, the impact on the properties of concrete, are described. The RBA has been treated to decrease the water absorption capacity by impregnation approach using specific impregnators. Afterwards, the RBA samples have been dried at two different temperatures in the laboratory oven—20 and 90 °C. Concretes using 4/8 fraction of the treated RBA instead of natural aggregate (NA) have been mixed and tested. The effectiveness of the RBA treatments have been evaluated on the basis of their influence on the properties of the hardened concrete; by means of the following tests: flexural strength, compressive strength, capillarity, total water absorption capacity, depth of water penetration under pressure, and frost resistance. The method of ranking by ordinal scale has been used as it is suitable for the comparison of a large set of results, while results have been analyzed in terms of the most important technological parameter that influences the quality of the concrete-effective water content. Out of all the tested surface-treatments of RBA, treatment by sodium water glass has the best potential for reduction of the water/cement (w/c) ratio. When the effective w/c ratio is kept within standard limits, concretes containing treated RBA are possible to be specified for various exposure classes and manufacturing in practice. The experiment confirms that at a constant amount of mixing water, with decreasing water absorption of RBA, the effective amount of water in the concrete increases and, hence, the final properties of the concrete decrease (get worse). As the water absorption of the RBA declines, there is a potential for the reduction of the w/c ratio and improvement in the quality of the concrete. PMID:28773277

Evaluation of the Influence of Specific Surface Treatments of RBA on a Set of Properties of Concrete.

PubMed

Ondova, Marcela; Sicakova, Alena

2016-03-03

High water absorption of recycled brick aggregate (RBA) is one of the most discussed parameters in terms of its application in the production of concrete-its influence on the amount of mixing water and, hence, the quality of the concrete, is usually considered negative. In this paper, different methods of decreasing the absorption of RBA and, consequently, the impact on the properties of concrete, are described. The RBA has been treated to decrease the water absorption capacity by impregnation approach using specific impregnators. Afterwards, the RBA samples have been dried at two different temperatures in the laboratory oven-20 and 90 °C. Concretes using 4/8 fraction of the treated RBA instead of natural aggregate (NA) have been mixed and tested. The effectiveness of the RBA treatments have been evaluated on the basis of their influence on the properties of the hardened concrete; by means of the following tests: flexural strength, compressive strength, capillarity, total water absorption capacity, depth of water penetration under pressure, and frost resistance. The method of ranking by ordinal scale has been used as it is suitable for the comparison of a large set of results, while results have been analyzed in terms of the most important technological parameter that influences the quality of the concrete-effective water content. Out of all the tested surface-treatments of RBA, treatment by sodium water glass has the best potential for reduction of the water/cement (w/c) ratio. When the effective w/c ratio is kept within standard limits, concretes containing treated RBA are possible to be specified for various exposure classes and manufacturing in practice. The experiment confirms that at a constant amount of mixing water, with decreasing water absorption of RBA, the effective amount of water in the concrete increases and, hence, the final properties of the concrete decrease (get worse). As the water absorption of the RBA declines, there is a potential for the reduction of the w/c ratio and improvement in the quality of the concrete.

Water Quality and Brain Function

PubMed Central

Campbell, Arezoo

2017-01-01

In the United States, regulations are in place to ensure the quality of drinking water. Such precautions are intended to safeguard the health of the population. However, regulatory guidelines may at times fail to achieve their purpose. This may be due to lack of sufficient data regarding the health hazards of chronic low dose exposure to contaminants or the introduction of new substances that pose a health hazard risk that has yet to be identified. In this review, examples of different sources of contaminants in drinking water will be discussed, followed by an evaluation of some select individual toxicants with known adverse neurological impact. The ability of mixtures to potentially cause additive, synergistic, or antagonistic neurotoxic responses will be briefly addressed. The last section of the review will provide examples of select mechanisms by which different classes of contaminants may lead to neurological impairments. The main objective of this review is to bring to light the importance of considering trace amounts of chemicals in the drinking water and potential brain abnormalities. There is continued need for toxicology studies to better understand negative consequences of trace amounts of toxins and although it is beyond the scope of this brief overview it is hoped that the review will underscore the paucity of studies focused on determining how long-term exposure to minute levels of contaminants in drinking water may pose a significant health hazard. PMID:29267198

Appraisal of data for ground-water quality in Nebraska

USGS Publications Warehouse

Engberg, R.A.

1984-01-01

This report summarizes existing data for groundwater quality in Nebraska and indicates their adequacy as a data base. Analyses have been made of water from nearly 10,000 wells by 8 agencies. Those analyses that meet reliability criteria have been aggregated by geologic source of water into four principal aquifer groupings--Holocene-Pleistocene aquifers, Tertiary aquifers, Mesozoic aquifers, and Paleozoic aquifers. For each aquifer grouping, data for specific conductance and 24 constituents in the water are summarized statistically. Also, diagrams are presented showing differences in statistical parameters, or in chemical composition, of water from the different aquifer groupings. Additionally, for each grouping except Paleozoic aquifers, maps show ranges in concentration of dissolved solids, calcium, alkalinity, and sulfate. In areas where data are insufficient to delimit, ranges in concentration also are shown on the maps. Point-source contamination has been identified at 41 locations and nonpoint-source contamination in 3 areas, namely, the central Platte Valley, Holt County, and Boyd County. Potential for nonpoint-source contamination exists in 10 major areas, which together comprise more than one-third of the State. Existing data are mostly from specific projects having limited areas and objectives. Consequently, a lack of data exists for other areas and for certain geologic units, particularly the Mesozoic and Paleozoic aquifers. Specific data needs for each of the four principal aquifer groupings are indicated in a matrix table.

Human activities and threats of chronic epidemics in a fragile geologic environment

NASA Astrophysics Data System (ADS)

Nkhuwa, D. C. W.

The quality of groundwater in the Lusaka aquifer is becoming matter of great concern to the city’s inhabitants. Access to good quality water in sufficient quantities to support life is becoming increasingly scarce, while waterborne diseases are becoming rife and on the increase. As a result of rapid urbanisation and a proportionate increase in human activities, there has been increased use of the ground to dispose of different types of solid and liquid wastes. Usually, this has been with no due consideration of the underlying geology. Such unsatisfactory management of wastes over a fragile geologic environment has heightened threats of aquifer pollution through unhindered access of components of the wastes to the groundwater store. Consumption of such water may be responsible for the near-endemic outbreaks of diarrhoeal and dysentery cases in parts of the city. As the demand for water continues to heighten, current trends of aquifer pollution of the meagre available water resources threaten to exacerbate this scenario. Consequently, this will impose further restrictions on the city environment’s ability to sustain human life. This paper highlights some of Lusaka’s typical and pertinent water supply problems. It also implicitly expresses the urgent need for reconciliation between human activities and the underlying geology and hydrogeology in order to preserve an environment that promotes and perpetuates good human health.

An Energy Efficient Adaptive Sampling Algorithm in a Sensor Network for Automated Water Quality Monitoring.

PubMed

Shu, Tongxin; Xia, Min; Chen, Jiahong; Silva, Clarence de

2017-11-05

Power management is crucial in the monitoring of a remote environment, especially when long-term monitoring is needed. Renewable energy sources such as solar and wind may be harvested to sustain a monitoring system. However, without proper power management, equipment within the monitoring system may become nonfunctional and, as a consequence, the data or events captured during the monitoring process will become inaccurate as well. This paper develops and applies a novel adaptive sampling algorithm for power management in the automated monitoring of the quality of water in an extensive and remote aquatic environment. Based on the data collected on line using sensor nodes, a data-driven adaptive sampling algorithm (DDASA) is developed for improving the power efficiency while ensuring the accuracy of sampled data. The developed algorithm is evaluated using two distinct key parameters, which are dissolved oxygen (DO) and turbidity. It is found that by dynamically changing the sampling frequency, the battery lifetime can be effectively prolonged while maintaining a required level of sampling accuracy. According to the simulation results, compared to a fixed sampling rate, approximately 30.66% of the battery energy can be saved for three months of continuous water quality monitoring. Using the same dataset to compare with a traditional adaptive sampling algorithm (ASA), while achieving around the same Normalized Mean Error (NME), DDASA is superior in saving 5.31% more battery energy.

Rehydration of freeze-dried and convective dried boletus edulis mushrooms: effect on some quality parameters.

PubMed

Hernando, I; Sanjuán, N; Pérez-Munuera, I; Mulet, A

2008-10-01

Quality of rehydrated products is a key aspect linked to rehydration conditions. To assess the effect of rehydration temperature on some quality parameters, experiments at 20 and 70 degrees C were performed with convective dried and freeze-dried Boletus edulis mushrooms. Rehydration characteristics (through Peleg's parameter, k(1), and equilibrium moisture, W(e)), texture (Kramer), and microstructure (Cryo-Scanning Electron Microscopy) were evaluated. Freeze-dried samples absorbed water more quickly and attained higher W(e) values than convective dried ones. Convective dehydrated samples rehydrated at 20 degrees C showed significantly lower textural values (11.9 +/- 3.3 N/g) than those rehydrated at 70 degrees C (15.7 +/- 1.2 N/g). For the freeze-dried Boletus edulis, the textural values also exhibited significant differences, being 8.2 +/- 1.3 and 10.5 +/- 2.3 N/g for 20 and 70 degrees C, respectively. Freeze-dried samples showed a porous structure that allows rehydration to take place mainly at the extracellular level. This explains the fact that, regardless of temperature, freeze-dried mushrooms absorbed water more quickly and reached higher W(e) values than convective dried ones. Whatever the dehydration technique used, rehydration at 70 degrees C produced a structural damage that hindered water absorption; consequently lower W(e) values and higher textural values were attained than when rehydrating at 20 degrees C.

An Energy Efficient Adaptive Sampling Algorithm in a Sensor Network for Automated Water Quality Monitoring

PubMed Central

Shu, Tongxin; Xia, Min; Chen, Jiahong; de Silva, Clarence

2017-01-01

Power management is crucial in the monitoring of a remote environment, especially when long-term monitoring is needed. Renewable energy sources such as solar and wind may be harvested to sustain a monitoring system. However, without proper power management, equipment within the monitoring system may become nonfunctional and, as a consequence, the data or events captured during the monitoring process will become inaccurate as well. This paper develops and applies a novel adaptive sampling algorithm for power management in the automated monitoring of the quality of water in an extensive and remote aquatic environment. Based on the data collected on line using sensor nodes, a data-driven adaptive sampling algorithm (DDASA) is developed for improving the power efficiency while ensuring the accuracy of sampled data. The developed algorithm is evaluated using two distinct key parameters, which are dissolved oxygen (DO) and turbidity. It is found that by dynamically changing the sampling frequency, the battery lifetime can be effectively prolonged while maintaining a required level of sampling accuracy. According to the simulation results, compared to a fixed sampling rate, approximately 30.66% of the battery energy can be saved for three months of continuous water quality monitoring. Using the same dataset to compare with a traditional adaptive sampling algorithm (ASA), while achieving around the same Normalized Mean Error (NME), DDASA is superior in saving 5.31% more battery energy. PMID:29113087

Habitat suitability criteria for assessment of instream flow needs of fish

USGS Publications Warehouse

Crance, Johnie H.

1989-01-01

In the western portion of the United States, competition for stream water gas often been fierce. Water resource management agencies in the southeastern United States, where water has been relatively abundant, are not being faced with similar competing demands for water, and with increasing pressures to develop and defend recommendations for protecting fish and invertebrates in streams. Streamflow depletion at any time can result in severe long-term effects on fish populations(Peters, 1982). The allocation of stream water to any numerous instream or offstream uses is tied to the issues of water quantity, quality, and timing, which center on two critical questions: (1)when and how much water of an acceptable quality should be left in a stream, and (2) what happens if flow regimes are changed? Answers to these questions will probably be complex, but reliable answers are needed to protect instream and offstream values. If instream flow interests expect to compete with offstream uses for limited water supplies, they must be able to determine reliable and defensible methods for determining instream flow needs and demonstrate the environmental consequences of altered flow regimes. My objectives in this paper are: (a) to present an overview of the need, development, and use of stream habitat suitability criteria, and the use of these criteria for the assessment of instream flow needs; (b) to give a status report on the plan of the National Ecology Research Center (NERC) for expansion of instream flow research in the Southeast; and (c) to discuss the relevancy of the research to river corridor management.

Deterioration of soil quality and pasture production linked to overgrazing in rangelands of Extremadura (SW Spain)

NASA Astrophysics Data System (ADS)

Pulido-Fernández, Manuel; Schnabel, Susanne; Francisco Lavado Contador, Joaquín; Lozano-Parra, Javier; González López, Francisco

2015-04-01

Soil degradation phenomena include water erosion and physical and biological processes have been already reported in rangelands of southwestern Spain. The increasing of the number of domestic animals since 1986 has been highlighted as one of the key causes. The main goal of this work is to analyze the effects of the excessive number of animals on soil quality and pasture production in privately-owned farms dedicated to extensive ranching. Soil properties, soil surface cover, erosion features, pasture production and composition, rainfall and land management variables such as livestock density were analyzed during a period of 3 years (2008-2011). The study was carried out in 22 fenced units belonging to 10 farms distributed throughout the Spanish region of Extremadura. The occurrence of bare soil patches, and consequently water erosion processes, as well as an increasing in the mean values of bulk density from 5 to 10 cm in depth were observed in the fenced units with animal stocking rates exceeding 1 AU ha-1 (AU: animal cattle equivalent unit). Some indications which may serve to confirm the negative effect of increased bulk density on pasture production and quality were also found.

Elevated soil nitrogen pools after conversion of turfgrass to water-efficient residential landscapes

NASA Astrophysics Data System (ADS)

Heavenrich, Hannah; Hall, Sharon J.

2016-08-01

As a result of uncertain resource availability and growing populations, city managers are implementing conservation plans that aim to provide services for people while reducing household resource use. For example, in the US, municipalities are incentivizing homeowners to replace their water-intensive turfgrass lawns with water-efficient landscapes consisting of interspersed drought-tolerant shrubs and trees with rock or mulch groundcover (e.g. xeriscapes, rain gardens, water-wise landscapes). While these strategies are likely to reduce water demand, the consequences for other ecosystem services are unclear. Previous studies in controlled, experimental landscapes have shown that conversion from turfgrass to shrubs may lead to high rates of nutrient leaching from soils. However, little is known about the long-term biogeochemical consequences of this increasingly common land cover change across diverse homeowner management practices. We explored the fate of soil nitrogen (N) across a chronosequence of land cover change from turfgrass to water-efficient landscapes in privately owned yards in metropolitan Phoenix, Arizona, in the arid US Southwest. Soil nitrate ({{{{NO}}}3}--N) pools were four times larger in water-efficient landscapes (25 ± 4 kg {{{{NO}}}3}--N/ha 0-45 cm depth) compared to turfgrass lawns (6 ± 7 kg {{{{NO}}}3}--N/ha). Soil {{{{NO}}}3}--N also varied significantly with time since landscape conversion; the largest pools occurred at 9-13 years after turfgrass removal and declined to levels comparable to turfgrass thereafter. Variation in soil {{{{NO}}}3}--N with landscape age was strongly influenced by management practices related to soil water availability, including shrub cover, sub-surface plastic sheeting, and irrigation frequency. Our findings show that transitioning from turfgrass to water-efficient residential landscaping can lead to an accumulation of {{{{NO}}}3}--N that may be lost from the plant rooting zone over time following irrigation or rainfall. These results have implications for best management practices to optimize the benefits of water-conserving landscapes while protecting water quality.

Drinking water treatment using a submerged internal-circulation membrane coagulation reactor coupled with permanganate oxidation.

PubMed

Zhang, Zhongguo; Liu, Dan; Qian, Yu; Wu, Yue; He, Peiran; Liang, Shuang; Fu, Xiaozheng; Li, Jiding; Ye, Changqing

2017-06-01

A submerged internal circulating membrane coagulation reactor (MCR) was used to treat surface water to produce drinking water. Polyaluminum chloride (PACl) was used as coagulant, and a hydrophilic polyvinylidene fluoride (PVDF) submerged hollow fiber microfiltration membrane was employed. The influences of trans-membrane pressure (TMP), zeta potential (ZP) of the suspended particles in raw water, and KMnO 4 dosing on water flux and the removal of turbidity and organic matter were systematically investigated. Continuous bench-scale experiments showed that the permeate quality of the MCR satisfied the requirement for a centralized water supply, according to the Standards for Drinking Water Quality of China (GB 5749-2006), as evaluated by turbidity (<1 NTU) and total organic carbon (TOC) (<5mg/L) measurements. Besides water flux, the removal of turbidity, TOC and dissolved organic carbon (DOC) in the raw water also increased with increasing TMP in the range of 0.01-0.05MPa. High ZP induced by PACl, such as 5-9mV, led to an increase in the number of fine and total particles in the MCR, and consequently caused serious membrane fouling and high permeate turbidity. However, the removal of TOC and DOC increased with increasing ZP. A slightly positive ZP, such as 1-2mV, corresponding to charge neutralization coagulation, was favorable for membrane fouling control. Moreover, dosing with KMnO 4 could further improve the removal of turbidity and DOC, thereby mitigating membrane fouling. The results are helpful for the application of the MCR in producing drinking water and also beneficial to the research and application of other coagulation and membrane separation hybrid processes. Copyright © 2016. Published by Elsevier B.V.

Development of the Metropolitan Water Availability Index (MWAI) and short-term assessment with multi-scale remote sensing technologies.

PubMed

Chang, Ni-Bin; Yang, Y Jeffrey; Goodrich, James A; Daranpob, Ammarin

2010-06-01

Global climate change will influence environmental conditions including temperature, surface radiation, soil moisture, and sea level, and it will also significantly impact regional-scale hydrologic processes such as evapotranspiration (ET), precipitation, runoff, and snowmelt. The quantity and quality of water available for drinking and other domestic usage is also likely to be affected by changes in these processes. Consequently, it is necessary to assess and reflect upon the challenges ahead for water infrastructure and the general public in metropolitan regions. One approach to the problem is to use index-based assessment, forecasting and planning. The drought indices previously developed were not developed for domestic water supplies, and thus are insufficient for the purpose of such an assessment. This paper aims to propose and develop a "Metropolitan Water Availability Index (MWAI)" to assess the status of both the quantity and quality of available potable water sources diverted from the hydrologic cycle in a metropolitan region. In this approach, the accessible water may be expressed as volume per month or week (i.e., m(3)/month or m(3)/week) relative to a prescribed historical record, and such a trend analysis may result in final MWAI values ranging from -1 to +1 for regional water management decision making. The MWAI computation uses data and information from both historical point measurements and spatial remote-sensing based monitoring. Variables such as precipitation, river discharge, and water quality changes at drinking water plant intakes at specific locations are past "point" measurements in MWAI calculations. On the other hand, remote sensing provides information on both spatial and temporal distributions of key variables. Examples of remote-sensing images and sensor network technologies are in-situ sensor networks, ground-based radar, air-borne aircraft, and even space-borne satellites. A case study in Tampa Bay, Florida is described to demonstrate the short-term assessment of the MWAI concept at a practical level. It is anticipated that such a forecasting methodology may be extended for middle-term and long-term water supply assessment. (c) 2010 Elsevier Ltd. All rights reserved.

An integrative approach to characterize hydrological processes and water quality in a semi-arid watershed in Northeastern Brazil

NASA Astrophysics Data System (ADS)

Franklin, M. R.; Fernandes, N.; Veiga, L. H. S.; Melo, L. R.; Santos, A. C. S.; Araujo, V. P.

2014-12-01

Arid and semi-arid regions face serious challenges in the management of scarce water resources. This situation tends to become worse with the increasing population growth rates and consequently increasing water demand. Groundwater is the most important water resource in these areas and, therefore, the sustainability of its use depends on the effectiveness in which it is managed, both in terms of quantity and quality. The Caetité Experimental Basin (CEB), located in a semi-arid region of Northeastern Brazil, faces not only the challenges associated with water scarcity, but also changes in landscape and potential contamination processes due to mining activity. The only active uranium production center in Brazil (URA) is located in this watershed and the sustainability of mining and milling operations as well as the survival of the local community are highly dependent on the availability of groundwater resources. Hydrogeological studies in this area are scarce, and the potential contamination and overexploitation of groundwater can not be ruled out. Therefore, a national project was launched in order to improve the understanding and quantification of the interaction between the hydrogeological system and human health. The methodological approach involved hydrological and geochemical monitoring and characterization of the CEB, use of isotopic techniques, groundwater modeling, water quality diagnosis and human health risk assessment due to water ingestion. The results suggested that the groundwater in the CEB are not totally connected, with evidence of a mixture of recent and old waters. The Na-Ca-HCO3-Cl is the dominant water type (50%) followed by Ca-Na-HCO3-Cl water type (17%). The relevant non-radioactive contaminants are Mn, F, NO3 and Ba, mostly from natural origin, with the exception of NO3 that could be associated with the livestock activities. The estimated effective doses due to groundwater ingestion containing radionuclides are below the recommended reference level (1 mSv/year) for drinking water in existing exposure situation and do not represent significant radiological impact.

Assessment of ecosystem response to a temporary water level drawdown and subsequent refilling at Topock Marsh, Arizona—July 2011–October 2014

USGS Publications Warehouse

Daniels, Joan S.; Haegele, Jeanette C.

2017-01-20

Topock Marsh is a 1,637-hectare (4,045-acre) wetland adjacent to the Colorado River near Needles, California, and a main feature of Havasu National Wildlife Refuge (NWR). The U.S. Fish and Wildlife Service, in cooperation with the Bureau of Reclamation, began construction of an infrastructure improvement project in 2010 to increase the efficiency of water use and to help protect the habitats and species found within the Havasu NWR. During construction, normal water delivery from the Colorado River into Topock Marsh through the Inlet Canal was restricted, which resulted in unusually low water elevations  in 2011. The U.S. Geological Survey, commissioned by the U.S. Fish and Wildlife Service, undertook the investigation of the water quality and aquatic flora and fauna during the low water conditions. Subsequently, water elevations in the marsh returned to more normal elevations after the new concrete-lined Fire Break Canal became fully operational in January 2012.The U.S. Geological Survey made 11 field trips to the Havasu NWR between July 2011 and October 2014 to assess the effects of the temporary low water conditions and the change of inflow location (from the Inlet Canal to the Fire Break Canal) on water quality and aquatic habitat. The following conditions were monitored: water quality, sediment and plant chemistry, phytoplankton, zooplankton, aquatic macro-invertebrates, and emergent and submerged aquatic vegetation (SAV). Water-quality and biota data collected during 2013–14 were then compared with data collected during the 2011–12 low water period.Once the new Fire Break Canal became operational and Colorado River water flowed regularly into the marsh, concentrations of several water quality parameters decreased (for example, specific conductance, total dissolved solids, turbidity, chlorophyll a, and total and organic nitrogen), and phytoplankton abundance was reduced at the upstream sampling stations (TP-3, TP-2, and TP-6); the water flow pushed water with higher concentrations of these components downstream (measured at TP-8). The upstream sampling locations in 2013–14 had decreased turbidity, therefore more SAV biomass accumulated, especially in shallow areas with water depths of ≤1.0 meter (≤3.3 feet). However, the furthest downstream station had higher turbidity caused by both the suspension of autochthonous sediment and high phytoplankton density and biovolume. This higher turbidity resulted in minimal SAV growth, especially in the deeper water (>1.0 meter [>3.3 feet]). Emergent vegetation not only survived the low water conditions of 2011, but expanded its areal coverage and subsequently thrived in the higher water elevations. Overall, no immediate critically negative consequences were detected for aquatic fauna or flora that could be attributd unequivocally to the effect of low water levels. Concentrations of nutrient and trace elements in all water samples were below wildlife toxicity thresholds as established by Arizona Department of Environmental Quality. Three nonnative species were discovered shortly after the Fire Break Canal went into operation. Of the three, gizzard shad (Dorosoma cepedianum) and Eurasian watermilfoil (Myriophyllum spicatum) increased substantially in numbers from 2011–14, but quagga mussels (Dreissena bugensis) did not increase. Future monitoring will determine the long-term impact of the new flow regime

Environmental consequences of the Retsof Salt Mine roof collapse

USGS Publications Warehouse

Yager, Richard M.

2013-01-01

In 1994, the largest salt mine in North America, which had been in operation for more than 100 years, catastrophically flooded when the mine ceiling collapsed. In addition to causing the loss of the mine and the mineral resources it provided, this event formed sinkholes, caused widespread subsidence to land, caused structures to crack and subside, and changed stream flow and erosion patterns. Subsequent flooding of the mine drained overlying aquifers, changed the groundwater salinity distribution (rendering domestic wells unusable), and allowed locally present natural gas to enter dwellings through water wells. Investigations including exploratory drilling, hydrologic and water-quality monitoring, geologic and geophysical studies, and numerical simulation of groundwater flow, salinity, and subsidence have been effective tools in understanding the environmental consequences of the mine collapse and informing decisions about management of those consequences for the future. Salt mines are generally dry, but are susceptible to leaks and can become flooded if groundwater from overlying aquifers or surface water finds a way downward into the mined cavity through hundreds of feet of rock. With its potential to flood the entire mine cavity, groundwater is a constant source of concern for mine operators. The problem is compounded by the viscous nature of salt and the fact that salt mines commonly lie beneath water-bearing aquifers. Salt (for example halite or potash) deforms and “creeps” into the mined openings over time spans that range from years to centuries. This movement of salt can destabilize the overlying rock layers and lead to their eventual sagging and collapse, creating permeable pathways for leakage of water and depressions or openings at land surface, such as sinkholes. Salt is also highly soluble in water; therefore, whenever water begins to flow into a salt mine, the channels through which it flows increase in diameter as the surrounding salt dissolves. Some mines leak at a slow rate for decades before a section of rock gives way, allowing what initially was a trickle of water to suddenly become a cascade and finally a torrent. Other mines become flooded and are destroyed when an errant drill hole punctures the mine ceiling, allowing water from overlying sources to flow into the mine. Either scenario can cause catastrophic flooding and permanent loss of the mine. Occasionally, a mine that has remained dry for a century will undergo a roof collapse that results in flooding.

Land use change and effects on water quality and ecosystem health in the Lake Tahoe basin, Nevada and California

USGS Publications Warehouse

Forney, William; Richards, Lora; Adams, Kenneth D.; Minor, Timothy B.; Rowe, Timothy G.; Smith, J. LaRue; Raumann, Christian G.

2001-01-01

Human activity in the Lake Tahoe Basin has increased substantially in the past four decades, causing significant impacts on the quality and clarity of the lake's famous deep, clear water. Protection of Lake Tahoe and the surrounding environment has become an important activity in recent years. A variety of agencies, including the Tahoe Regional Planning Agency, Tahoe Research Group of the University of California at Davis, Desert Research Institute of the University and Community College System of Nevada, U.S. Geological Survey (USGS), and a host of State (both Nevada and California) and local agencies have been monitoring and conducting research in the Basin in order to understand how the lake functions and to what extent humans have affected its landscape and ecosystem processes. In spite of all of these activities, there remains a lack of comprehensive land use change data and analysis for the Basin. A project is underway that unites the land cover mapping expertise of the USGS National Mapping Discipline with the hydrologic expertise of the Water Resources Discipline to assess the impacts of urban growth and land use change in the Lake Tahoe Basin. Three activities are planned over the next 3 years: (1) mapping the current and historic state of the land surface, (2) conducting analysis to document patterns, rates, and trends in urbanization, land use change, and ecosystem health, and (3) assessing the causes and consequences of land use change with regard to water quality and ecosystem health. We hypothesize that changes in the extent of urban growth and the corresponding increases in impervious surfaces and decreases in natural vegetation have resulted in severe impacts on ecosystem health and integrity, riparian zones and water quality over time. We are acting on multiple fronts to test this hypothesis through the quantification of landscape disturbances and impacts.

Water quality and amphibian health in the Big Bend region of the Rio Grande Basin

USGS Publications Warehouse

Sharma, Bibek; Hu, F.; Carr, J.A.; Patino, Reynaldo

2011-01-01

Male and female Rio Grande leopard frogs (Rana berlandieri) were collected in May 2005 from the main stem and tributaries of the Rio Grande in the Big Bend region of Texas. Frogs were examined for (1) incidence of testicular ovarian follicles in males; (2) thyroid epithelial cell height, a potential index of exposure to thyroid-disrupting contaminants; and (3) incidence of liver melanomacrophage aggregates, a general index of exposure to contaminants. Standard parameters of surface water quality and concentrations of selected elements, including heavy metals, were determined at each frog collection site. Heavy metals also were measured in whole-frog composite extracts. Water cadmium concentrations in most sites and chloride concentrations in the main stem exceeded federal criteria for freshwater aquatic life. Mercury was detected in frogs from the two collection sites in Terlingua Creek. There was a seventeen percent incidence of testicular ovarian follicles in male frogs. Mean thyroid epithelial cell height was greater in frogs from one of the Terlingua Creek sites (Terlingua Abajo). No differences were observed in the incidence of hepatic macrophage aggregates among sites. In conclusion, although potential cause-effect relationships between indices of habitat quality and amphibian health could not be established, the results of this study raise concerns about the general quality of the aquatic habitat and the potential long-term consequences to the aquatic biota of the Big Bend region. The presence of ovarian follicles in male frogs is noteworthy but further study is necessary to determine whether this phenomenon is natural or anthropogenically induced.

Surface and groundwater drought evaluation with respect to aquatic habitat quality in the upper Nitra River Basin in Slovakia

NASA Astrophysics Data System (ADS)

Fendekova, M.; Fendek, M.; Macura, V.; Kralova, J.

2012-04-01

Hydrological drought is being broadly studied within last decades in many countries. It is because of increasing frequency of drought periods occurrence also in mild climate conditions, leading to unexpected and undesired consequences for environment and various spheres of the state economy. Drought affects water availability for plants, animals and human society. Natural conditions of drought occurrence are often combined with human activities strengthening drought consequences. Lack of water in the nature, connected to meteorological and hydrological drought occurrence, increases at the same time needs for surface and groundwater in many types of human activities (agriculture, industrial production, electric power generation…). Drought can be identified within the low flow phase of the flow regime. Flow regime is considered for one of the most important conditions influencing quality of the river ecosystems. Occurrence of meteorological, surface and groundwater droughts was analyzed for the upper part of the Nitra River catchment in Slovakia. Drought occurrence was studied in two gauging profiles on the Nitra River - in Klacno and Nedozery, both representing the headwater profiles. The threshold level method was used for groundwater drought analysis. Base flow values were separated from the discharge hydrograms using the HydroOffice 2010 statistical program package. The influence of surface water drought on groundwater level was analyzed. Habitat suitability curves derived according to IFIM methodology were constructed for different fish species at Nedozery profile. The influence of different low flow values from 600 to 150 L/s on fish amount, size and species variability was studied. In the end, the minimum flow, bellow which unfavourable life conditions occur, was estimated. The results showed the necessity of taking into account the ecological parameters when estimating the ecological status of surface water bodies. Such an approach is fully compatible with the requirements of the Directive 2000/60/EC and with the integrated water resources management strategy. Acknowledgment: The research was done with the financial support of the VEGA project grant No. 1/1327/12.

Pasture degradation in Tibet: Drivers, mechanisms and consequences for C stocks and ecosystem stability

NASA Astrophysics Data System (ADS)

Kuzyakov, Yakov; Schleuss, Per-Marten; Guggenberger, Georg; Miehe, Georg; Coners, Heinz; Foken, Thomas; Wesche, Karsten; Hafner, Silke; Biermann, Tobias; Babel, Wolfgang; Gerken, Tobias; Unteregelsbacher, Sebastian; Seeber, Elke; Spielvogel, Sandra; Ingrisch, Johannes; Li, Xiaogang; Yue, Sun; Li, Qianru; Xu, Xingliang

2017-04-01

Kobresia grasslands on Tibetan Plateau have accumulated tremendous organic carbon (C) stocks, are an important grazing ground for local herdsmen, host a major portion of the regional terrestrial biodiversity, and supply large areas of SE Asia with water. All these ecosystem functions are threatened by large-scale soil degradation on the Tibetan Plateau. Nonetheless, the patterns and mechanisms of Kobresia pasture degradation, visible across the entire Tibetan Plateau, remain unknown. In the K. pygmaea core area, we studied natural and anthropogenic drivers of pasture degradation to discover new mechanisms and associated processes of soil organic carbon (SOC) loss. We show that livestock overgrazing and trampling in recent decades have triggered grassland degradation by initiating plant death and reducing grassland recovery. Combined with the harsh climate, this destroys the protective Kobresia turf. Considering these processes as well as other anthropogenic and natural drivers, a novel pasture degradation concept was developed. Pasture soils corresponding to the fiwe degradation stages were sampled and analyzed for physical, chemical and biological properties. Soil drought and frost lead to polygonal cracking of the Kobresia turf, already weakened by overgrazing. This induces gradual erosion by wind and water, extends the cracks and removes the upper carbon-enriched soil. Erosion-derived SOC losses amount to 5 kg C m-2 and are aggravated by decreasing root C input and increased SOC mineralization (both ca. 2.5 kg C m-2). Mineralization-derived SOC loss was reflected by a negative δ13C shift of SOC going from intact to severely degraded stages, and was caused by a relative enrichment of 13C-depleted lignin. In sum, degradation has released tremendous amounts of carbon back into the atmosphere as CO2, or as increased sediment load in rivers, connected with declining water quality off-site. Affected by changed local water budget, the regional clouds' formation starts earlier and decreases the Kobresia pasture recovery potential. We conclude that the combined anthropogenic and natural impacts leading to pasture degradation have immense consequences for C sequestration, atmospheric CO2, water quality and ecosystem stability.

Identifying potential areas for biofuel production and evaluating the environmental effects: a case study of the James River Basin in the Midwestern United States

USGS Publications Warehouse

Wu, Yiping; Liu, Shu-Guang; Li, Zhengpeng

2012-01-01

Biofuels are now an important resource in the United States because of the Energy Independence and Security Act of 2007. Both increased corn growth for ethanol production and perennial dedicated energy crop growth for cellulosic feedstocks are potential sources to meet the rising demand for biofuels. However, these measures may cause adverse environmental consequences that are not yet fully understood. This study 1) evaluates the long-term impacts of increased frequency of corn in the crop rotation system on water quantity and quality as well as soil fertility in the James River Basin and 2) identifies potential grasslands for cultivating bioenergy crops (e.g. switchgrass), estimating the water quality impacts. We selected the soil and water assessment tool, a physically based multidisciplinary model, as the modeling approach to simulate a series of biofuel production scenarios involving crop rotation and land cover changes. The model simulations with different crop rotation scenarios indicate that decreases in water yield and soil nitrate nitrogen (NO3-N) concentration along with an increase in NO3-N load to stream water could justify serious concerns regarding increased corn rotations in this basin. Simulations with land cover change scenarios helped us spatially classify the grasslands in terms of biomass productivity and nitrogen loads, and we further derived the relationship of biomass production targets and the resulting nitrogen loads against switchgrass planting acreages. The suggested economically efficient (planting acreage) and environmentally friendly (water quality) planting locations and acreages can be a valuable guide for cultivating switchgrass in this basin. This information, along with the projected environmental costs (i.e. reduced water yield and increased nitrogen load), can contribute to decision support tools for land managers to seek the sustainability of biofuel development in this region.

Dissolved Concentrations, Sources, and Risk Evaluation of Selected Metals in Surface Water from Mangla Lake, Pakistan

PubMed Central

Saleem, Muhammad; Iqbal, Javed; Shah, Munir H.

2014-01-01

The present study is carried out for the assessment of water quality parameters and selected metals levels in surface water from Mangla Lake, Pakistan. The metal levels (Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Na, Ni, Pb, Sr, and Zn) were determined by flame atomic absorption spectrophotometry. Average levels of Cd, Co, Cr, Ni, and Pb were higher than the allowable concentrations set by national and international agencies. Principal component analysis indicated significant anthropogenic contributions of Cd, Co, Cr, Ni, and Pb in the water reservoir. Noncarcinogenic risk assessment was then evaluated using Hazard Quotient (HQing/derm) and Hazard Index (HIing/derm) following USEPA methodology. For adults and children, Cd, Co, Cr, and Pb (HQing > 1) emerged as the most important pollutants leading to noncarcinogenic concerns via ingestion route, whereas there was no risk via dermal contact of surface water. This study helps in establishing pollutant loading reduction goal and the total maximum daily loads, and consequently contributes to preserve public health and develop water conservation strategy. PMID:24744690

Marine microbial communities of the Great Barrier Reef lagoon are influenced by riverine floodwaters and seasonal weather events.

PubMed

Angly, Florent E; Heath, Candice; Morgan, Thomas C; Tonin, Hemerson; Rich, Virginia; Schaffelke, Britta; Bourne, David G; Tyson, Gene W

2016-01-01

The role of microorganisms in maintaining coral reef health is increasingly recognized. Riverine floodwater containing herbicides and excess nutrients from fertilizers compromises water quality in the inshore Great Barrier Reef (GBR), with unknown consequences for planktonic marine microbial communities and thus coral reefs. In this baseline study, inshore GBR microbial communities were monitored along a 124 km long transect between 2011 and 2013 using 16S rRNA gene amplicon sequencing. Members of the bacterial orders Rickettsiales (e.g., Pelagibacteraceae) and Synechococcales (e.g., Prochlorococcus), and of the archaeal class Marine Group II were prevalent in all samples, exhibiting a clear seasonal dynamics. Microbial communities near the Tully river mouth included a mixture of taxa from offshore marine sites and from the river system. The environmental parameters collected could be summarized into four groups, represented by salinity, rainfall, temperature and water quality, that drove the composition of microbial communities. During the wet season, lower salinity and a lower water quality index resulting from higher river discharge corresponded to increases in riverine taxa at sites near the river mouth. Particularly large, transient changes in microbial community structure were seen during the extreme wet season 2010-11, and may be partially attributed to the effects of wind and waves, which resuspend sediments and homogenize the water column in shallow near-shore regions. This work shows that anthropogenic floodwaters and other environmental parameters work in conjunction to drive the spatial distribution of microorganisms in the GBR lagoon, as well as their seasonal and daily dynamics.

Spatiotemporal distribution of algal and nutrient, and their correlations based on long-term monitoring data in Lake Taihu, China

NASA Astrophysics Data System (ADS)

Acharya, K.; Li, Y.; Stone, M.; Yu, Z.; Young, M.; Shafer, D. S.; Zhu, J.; Warwick, J. J.

2009-12-01

Eutrophication in Lake Taihu - China’s third largest freshwater lake - has led to deterioration of water quality and caused more frequent cyanobacteria blooms at many lake locations in recent years. Eutrophication is thought to be fueled by increased nutrient loading, a consequence of rapid population and economic growth in the region. To understand the spatiotemporal distribution of algal blooms, a database was developed that includes long-term meteorological, hydrological, water quality, and socioeconomic data from the Lake Taihu watershed. The data were collected through various field observations, and augmented with information from local and provincial agencies, and universities. Based on the data, spatiotemporal distributions of, and correlations between, chlorophyll-a (Chl-a), total phosphorus (TP), total nitrogen (TN) and water temperature (WT) were analyzed. Results revealed a high degree of correlation between TP and Chl-a concentrations during warm seasons, with high concentrations of both substances present in the northern and northwest portions of the lake. During winter months, Chl-a concentrations were more strongly correlated with WT. Spatial trends in TP and TN concentrations corresponded to observed nutrient fluxes from adjoining rivers in densely populated areas, demonstrating the influence of watershed pollutant loads on lake water quality. Among important questions to be answered is whether wind-driven resuspension of existing nutrients in sediments in this shallow (< 3 m) lake may cause cyanobacteria blooms to begin. This study identifies other questions, data gaps, and research needs, and provides a foundation for improving lake management strategies.

Marine microbial communities of the Great Barrier Reef lagoon are influenced by riverine floodwaters and seasonal weather events

PubMed Central

Heath, Candice; Morgan, Thomas C.; Tonin, Hemerson; Rich, Virginia; Schaffelke, Britta; Bourne, David G.; Tyson, Gene W.

2016-01-01

The role of microorganisms in maintaining coral reef health is increasingly recognized. Riverine floodwater containing herbicides and excess nutrients from fertilizers compromises water quality in the inshore Great Barrier Reef (GBR), with unknown consequences for planktonic marine microbial communities and thus coral reefs. In this baseline study, inshore GBR microbial communities were monitored along a 124 km long transect between 2011 and 2013 using 16S rRNA gene amplicon sequencing. Members of the bacterial orders Rickettsiales (e.g., Pelagibacteraceae) and Synechococcales (e.g., Prochlorococcus), and of the archaeal class Marine Group II were prevalent in all samples, exhibiting a clear seasonal dynamics. Microbial communities near the Tully river mouth included a mixture of taxa from offshore marine sites and from the river system. The environmental parameters collected could be summarized into four groups, represented by salinity, rainfall, temperature and water quality, that drove the composition of microbial communities. During the wet season, lower salinity and a lower water quality index resulting from higher river discharge corresponded to increases in riverine taxa at sites near the river mouth. Particularly large, transient changes in microbial community structure were seen during the extreme wet season 2010–11, and may be partially attributed to the effects of wind and waves, which resuspend sediments and homogenize the water column in shallow near-shore regions. This work shows that anthropogenic floodwaters and other environmental parameters work in conjunction to drive the spatial distribution of microorganisms in the GBR lagoon, as well as their seasonal and daily dynamics. PMID:26839738

Surface water, groundwater, and social science measurements in a prototype hydrologic observatory

NASA Astrophysics Data System (ADS)

Genereux, D.; Duffy, C.; Famiglietti, J.; Helly, J.; Hooper, R.; Krajewski, W.; McKnight, D.; Ogden, F.; Reckhow, K.; Scanlon, B.; Shabmasn, L.

2003-12-01

We convened in late April 2003 to begin work on the design for a "paper" prototype hydrologic observatory (HO) in the watershed of the Neuse estuary in North Carolina. This design example was to specify what would be measured in the HO, why, where, how, how often, and how much it would cost. This presentation focuses on aspects of the design related to stream and river measurements (discharge, water quality, fluvial geomorphology and sediment), groundwater measurements, and groundwater interaction with streams, rivers, and the estuary. Also considered is the collection of social sciences data to support multidisciplinary studies of land and water use and the consequences for flooding, water supply, and water quality. A second presentation in this session (Scanlon et al.) covers atmospheric and land surface aspects of the HO design, including recharge and ET. The design calls for measurements to quantify surface and subsurface hydrologic fluxes (water, solutes, sediment) into the Neuse estuary, and internally within the watershed at a wide range of spatial scales (about 5 orders of magnitude, roughly 0.1-10,000 square km). One hydrologic goal is to construct reliable water budgets for watersheds spanning this full range of scales, from the smallest to the full Neuse estuary watershed. A linked water quality goal is a strong quantitative characterization of the hydrologic storage and transport of nitrogen, a major water quality issue in this and many other large watersheds with major agricultural operations. Geomorphological observations will target the effects of physiographic and anthropogenic factors on rates of erosion, residence times of sediment in the fluvial system, and the role of wetlands and channel sources on the discharge of sediment and sorbed nutrients to the Neuse estuary during extreme events. Measurements will span the entire Neuse watershed but be more concentrated in a subset of 6 intermediate-size watersheds (averaging about 500 square km) that represent zones of different geology, land use, and topography within the larger watershed. We do not claim that the design is "optimal" in a rigorous statistical sense, but believe the reasoning used in the design is sound and applicable to other sites. The design and its staged implementation plan are flexible and allow the reasonably full coverage of the hydrologic cycle (and reasonable core) necessary to yield new insights and to make the HO an attractive site for individual studies.

Consequences of using different soil texture determination methodologies for soil physical quality and unsaturated zone time lag estimates.

PubMed

Fenton, O; Vero, S; Ibrahim, T G; Murphy, P N C; Sherriff, S C; Ó hUallacháin, D

2015-11-01

Elucidation of when the loss of pollutants, below the rooting zone in agricultural landscapes, affects water quality is important when assessing the efficacy of mitigation measures. Investigation of this inherent time lag (t(T)) is divided into unsaturated (t(u)) and saturated (t(s)) components. The duration of these components relative to each other differs depending on soil characteristics and the landscape position. The present field study focuses on tu estimation in a scenario where the saturated zone is likely to constitute a higher proportion of t(T). In such instances, or where only initial breakthrough (IBT) or centre of mass (COM) is of interest, utilisation of site and depth specific "simple" textural class or actual sand-silt-clay percentages to generate soil water characteristic curves with associated soil hydraulic parameters is acceptable. With the same data it is also possible to estimate a soil physical quality (S) parameter for each soil layer which can be used to infer many other physical, chemical and biological quality indicators. In this study, hand texturing in the field was used to determine textural classes of a soil profile. Laboratory methods, including hydrometer, pipette and laser diffraction methods were used to determine actual sand-silt-clay percentages of sections of the same soil profile. Results showed that in terms of S, hand texturing resulted in a lower index value (inferring a degraded soil) than that of pipette, hydrometer and laser equivalents. There was no difference between S index values determined using the pipette, hydrometer and laser diffraction methods. The difference between the three laboratory methods on both the IBT and COM stages of t(u) were negligible, and in this instance were unlikely to affect either groundwater monitoring decisions, or to be of consequence from a policy perspective. When t(u) estimates are made over the full depth of the vadose zone, which may extend to several metres, errors resulting from the use of hydraulic parameters generated from hand texture data will be resultantly greater, and may lead to flawed predictions regarding the achievability of water policy targets. For this reason laboratory analysis, regardless of method, should be preferred to simple field assessments. Copyright © 2015 Elsevier B.V. All rights reserved.

Groundwater science relevant to the Great Lakes Water Quality Agreement: A status report

USGS Publications Warehouse

Grannemann, Norman G.; Van Stempvoort, Dale

2016-01-01

When the Great Lakes Water Quality Agreement (GLWQA) was signed in 1972 by the Governments of Canada and the United States (the “Parties”) (Environment Canada, 2013a), groundwater was not recognized as important to the water quality of the Lakes. At that time, groundwater and surface water were still considered as two separate systems, with almost no appreciation for their interaction. When the GLWQA was revised in 1978 (US Environmental Protection Agency (USEPA), 2012), groundwater contamination, such as that reported at legacy industrial sites such as those at Love Canal near the Niagara River, was squarely in the news. Consequently, the potential impacts of contaminated groundwater from such sites on Great Lakes water quality became a concern (Beck, 1979), and Annex 16 was added to the agreement, to address “pollution from contaminated groundwater” (Francis, 1989). However, no formal process for reporting under this annex was provided. The GLWQA Protocol in 1987 modified Annex 16 and called for progress reports beginning in 1988 (USEPA, 1988). The Protocol in 2012 provided a new Annex 8 to address groundwater more holistically (Environment 2 Canada, 2013b). Annex 8 (Environment Canada, 2013b) commits the Parties to coordinate groundwater science and management actions; as a first step, to “publish a report on the relevant and available groundwater science” by February 2015 (this report); and to “identify priorities for science activities and actions for groundwater management, protection, and remediation…” The broader mandate of Annex 8 is to (1) “identify groundwater impacts on the chemical, physical and biological integrity of the Waters of the Great Lakes;” (2) “analyze contaminants, including nutrients in groundwater, derived from both point and non-point sources impacting the Waters of the Great Lakes;” (3) “assess information gaps and science needs related to groundwater to protect the quality of the Waters of the Great Lakes;” and (4) “analyze other factors, such as climate change, that individually or cumulatively affect groundwater’s impact on the quality of the Waters of the Great Lakes.” A binational Annex 8 Subcommittee was formed to lead efforts to fulfill the mandate of this annex (members listed on p. i of this report). In turn, this subcommittee has recruited a task team to prepare this report (listed as authors of each chapter). This report addresses all of the above four objectives, based on a compilation of the “relevant and available groundwater science.” Specifically, the second objective (to “analyze contaminants”) is addressed by incorporating information obtained in ongoing monitoring and research activities conducted by the Parties, and by various other members of the Great Lakes Executive Committee.

Analysis of Heavy Metal Content (Pb) on Waters and Fish at The Floating Cages BPPP Ambon

NASA Astrophysics Data System (ADS)

Wattimena, Rachel L.; Selanno, Debby A. J.; Tuhumury, Semuel F.; Tuahatu, Juliana W.

2018-02-01

Coastal waters play important roles due to highly in natural resources and developing of environmental services. However, there are highly intensity of natural resources utilization, environment and settlement. Consequently, environment and natural resources would be degraded such as in the Ambon Bay. One of the potency at the Ambon Bay is mariculture area namely the floating cages (KJA) which belongs to Fisheries education and training (BPPP) Ambon. The research aimed to analyze physical-chemical of waters (temperature, pH, salinity and current speed), to analyze heavy metal concentration (Pb) on water and fish from floating cages (KJA) and to analyze waters pollution status at KJA BPPP Ambon. The average salinity of each floating cage ranged from 30.09 - 30.34°C, pH ranged from 8.03 - 8.44, salinity ranged from 31.36 - 33.34 PSU, and current speed at spring tide ranged from 0.5 - 55.8 Cm/sec while neap tide ranged from 0.1 - 9.8 Cm/sec. Heavy metal concentration (Pb) on waters was below the standard for waters quality and the average concentration was 0.002 mg/l. Whilst, the heavy metal concentration (Pb) on fishes was below standard for floating cages (floating cages 2-6) which was 0.05 and 0.17mg/l. Otherwise, floating cage 1 had been above maximum standard for fish food and its processing following SNI 7387:2009 (0.3mg/l) which was 0.31 mg/l. The status of waters pollution at KJA BPPP Ambon belonged to C class and could be categorized as moderate based on standard for waters quality issued by State Ministerial Decree for the Environment No. 51 Year 2004.

Fault tree analysis for integrated and probabilistic risk analysis of drinking water systems.

PubMed

Lindhe, Andreas; Rosén, Lars; Norberg, Tommy; Bergstedt, Olof

2009-04-01

Drinking water systems are vulnerable and subject to a wide range of risks. To avoid sub-optimisation of risk-reduction options, risk analyses need to include the entire drinking water system, from source to tap. Such an integrated approach demands tools that are able to model interactions between different events. Fault tree analysis is a risk estimation tool with the ability to model interactions between events. Using fault tree analysis on an integrated level, a probabilistic risk analysis of a large drinking water system in Sweden was carried out. The primary aims of the study were: (1) to develop a method for integrated and probabilistic risk analysis of entire drinking water systems; and (2) to evaluate the applicability of Customer Minutes Lost (CML) as a measure of risk. The analysis included situations where no water is delivered to the consumer (quantity failure) and situations where water is delivered but does not comply with water quality standards (quality failure). Hard data as well as expert judgements were used to estimate probabilities of events and uncertainties in the estimates. The calculations were performed using Monte Carlo simulations. CML is shown to be a useful measure of risks associated with drinking water systems. The method presented provides information on risk levels, probabilities of failure, failure rates and downtimes of the system. This information is available for the entire system as well as its different sub-systems. Furthermore, the method enables comparison of the results with performance targets and acceptable levels of risk. The method thus facilitates integrated risk analysis and consequently helps decision-makers to minimise sub-optimisation of risk-reduction options.

Characterizing Vineyard Water Status Variability in a Premium Winegrape Vineyard

NASA Astrophysics Data System (ADS)

Smart, David; Carvahlo, Angela

2017-04-01

One of the biggest challenges in viticulture and winemaking is managing and optimizing yield and quality across vineyard blocks that show high spatial variability. Studies have shown that zonal management of vine water status can contribute significantly to improving overall fruit quality and improving uniformity. Vine water status is a major parameter for vine management because it affects both wine quality and yield. In order to optimize vineyard management and harvesting practices, it is necessary to characterize vineyard variability in terms of water status. Establishing a targeted irrigation program first requires spatially characterizing the variability in vine water status of a vineyard. In California, due to the low or no rainfall during the active growing season, the majority of vineyards implement some type of irrigation management program. As water supplies continue to decrease as a consequence of persistent drought, establishing efficient and targeted water use programs is of growing importance in California. The aim of this work was to characterize the spatial variability of plant-water relations across a non-uniform 4 ha block in Napa Valley with the primary objective of establishing vineyard irrigation management zones. The study plot was divided into three sections, designated the North, Middle and South sections, each at about 1.3 hectares. Stem (Ψstem) and midday (Ψl) leaf water potential and predawn (ΨPD) water potential were measured at 36 locations within the block at 14 (Ψl), 10 (ΨPD) and 2 (Ψstem) points in time throughout the growing season. Of the three techniques utilized to evaluate water status, ΨPD and Ψstem were the most sensitive indicators of water stress conditions. An integrated overview of water use efficiency over the growing season was assessed by measuring the leaf carbon isotope ratio of δ13C. Fully mature leaves were sampled from 280 vines and results show, similarly to ΨPD and Ψstem, that the North section (-28.05%) was significantly different than the South (at -28.31) and Middle (at -28.33) sections. Interblock variability can be reduced by managing water supply to the North section independently of the South and Middle sections. For Napa due to foggy mornings and overcast skies, Ψl provided the least discriminatory water status measurements.

Ground-Water Quality and its Relation to Land Use on Oahu, Hawaii, 2000-01

USGS Publications Warehouse

Hunt, Charles D.

2003-01-01

Water quality in the main drinking-water source aquifers of Oahu was assessed by a one-time sampling of untreated ground water from 30 public-supply wells and 15 monitoring wells. The 384 square-mile study area, which includes urban Honolulu and large tracts of forested, agricultural, and suburban residential lands in central Oahu, accounts for 93 percent of the island's ground-water withdrawals. Organic compounds were detected in 73 percent of public-supply wells, but mostly at low concentrations below minimum reporting levels. Concentrations exceeded drinking-water standards in just a few cases: the solvent trichloroethene and the radionuclide radon-222 exceeded Federal standards in one public-supply well each, and the fumigants 1,2-dibromo-3-chloropropane (DBCP) and 1,2,3-trichloropropane (TCP) exceeded State standards in three public-supply wells each. Solvents, fumigants, trihalomethanes, and herbicides were prevalent (detected in more than 30 percent of samples) but gasoline components and insecticides were detected in few wells. Most water samples contained complex mixtures of organic compounds: multiple solvents, fumigants, or herbicides, and in some cases compounds from two or all three of these classes. Characteristic suites of chemicals were associated with particular land uses and geographic locales. Solvents were associated with central Oahu urban-military lands whereas fumigants, herbicides, and fertilizer nutrients were associated with central Oahu agricultural lands. Somewhat unexpectedly, little contamination was detected in Honolulu where urban density is highest, most likely as a consequence of sound land-use planning, favorable aquifer structure, and less intensive application of chemicals (or of less mobile chemicals) over recharge zones in comparison to agricultural areas. For the most part, organic and nutrient contamination appear to reflect decades-old releases and former land use. Most ground-water ages were decades old, with recharge dates ranging from pre-1940 to the present, and with most dates falling within the 1950s to 1980s time span. Several widely detected compounds were discontinued as long ago as the 1970s but have yet to be flushed from the ground-water system. Although large tracts of land in central Oahu have been converted from agriculture to residential urban use since the 1950s, water quality in the converted areas still more closely reflects the former agricultural land. It appears to be too early to detect a distinct water-quality signature characteristic of the newer urban use, although several urban turfgrass herbicides in use for just 10 years or so were detected in monitoring wells and may represent early arrivals of urban contaminants at the water table.

Evaluation of surface water quality indices and ecological risk assessment for heavy metals in scrap yard neighbourhood.

PubMed

Ojekunle, Olusheyi Z; Ojekunle, Olurotimi V; Adeyemi, Azeem A; Taiwo, Abayomi G; Sangowusi, Opeyemi R; Taiwo, Adewale M; Adekitan, Adetoun A

2016-01-01

Pollution of surface water with heavy metals from industrial activities especially those from scrap yard has caused a major threat to human life exposing man to series of hazard, diseases, disability and consequently death. This study focuses on water quality indices of Owode-Onirin and Lafenwa scrap yard with respect to its physicochemical parameters and heavy metal concentrations by evaluating Heavy Metal Pollution Index (HPI), Metal Index (MI) and Potential Ecological Risk Index (PERI). Fifteen water samples were selected randomly from two locations by purposive sampling methods. Five heavy metals which includes Nickel (Ni), Zinc (Zn), Copper (Cu), Cadmium (Cd), Lead (Pb) were analyzed using Atomic Absorption Spectroscopy and standard analytical procedure were follow to ensure accuracy. One way analysis of variance was carried out to analyse the data. The concentrations of the heavy metals were significantly different between sampling locations. However, the mean concentrations of Cd (0.0121 mg/L) were found to be above the highest permissible value of Standard Organization of Nigeria standards for drinking water (SON 2007) and WHO (Guidelines for drinking water quality: incorporating 1st and 2nd Addlenda. World Health Organization, Geneva, 2004) for drinking water. Although Pb was present in two out of the fifteen water samples with a mean value of (0.0324 mg/L) which was also above the highest permissible value. The mean concentrations of Zn (0.2149 mg/L) and Cu (0.0341 mg/L) are found to be below the highest permissible value of the mentioned guideline while no trace of Ni was found in the water samples across the two sampling locations. The mean HPI 518.55 is far above the critical value of 100, indicates that selected water samples are critically polluted with heavy metals. MI revealed low quality water with mean value 4.83, suggests that the selected water is seriously affected with the present of heavy metal. The Hakanson PERI indicated that of the five heavy metals, the risk coefficient of Zn, Pb, Cu, and Ni had light levels of contamination while the level of Cd contamination posed the most serious potential ecological risk, with an index value between 14.1 and 234. The study concluded that order of magnitude to this five heavy metals contamination is Cd > Pb > Zn > Cu > Ni.

The collapse of pelagic fishes in the upper San Francisco estuary

USGS Publications Warehouse

Sommer, T.; Armor, C.; Baxter, R.; Breuer, R.; Brown, L.; Chotkowski, M.; Culberson, S.; Feyrer, F.; Gingras, M.; Herbold, B.; Kimmerer, W.; Mueller-Solger, A.; Nobriga, M.; Souza, K.

2007-01-01

Although the pelagic fish community of the upper San Francisco Estuary historically has shown substantial variability, a recent collapse has captured the attention of resource managers, scientists, legislators, and the general public. The ecological and management consequences of the decline are most serious for delta smelt (Hypomesus transpacificus), a threatened species whose narrow range overlaps with large water diversions that supply water to over 25 million people. The decline occurred despite recent moderate hydrology, which typically results in at least modest recruitment, and investments of hundreds of millions of dollars in habitat restoration and environmental water allocations to support native fishes. In response to the pelagic fish collapse, an ambitious multi-agency research team has been working since 2005 to evaluate the causes of the decline, which likely include a combination of factors: stock-recruitment effects, a decline in habitat quality, increased mortality rates, and reduced food availability due to invasive species.

Assessment of water quality of rivers that serve as water sources for drinking and domestic functions in rural and pre-urban communities in Edo North, Nigeria.

PubMed

Beshiru, Abeni; Okareh, Oladapo T; Chigor, Vincent N; Igbinosa, Etinosa O

2018-06-09

Surface waters are important to humans because they are a significant water supply source. They are, however, under serious environmental stress and are being threatened as a consequence of developmental activities. The present study describes the physicochemical properties and water quality indices of five different rivers used for drinking and other domestic activities in rural and pre-urban communities in Edo North, Nigeria. The physicochemical variable ranges include pH [wet season (6.47 ± 0.30-6.89 ± 0.11), dry season (6.61 ± 0.14-7.84 ± 0.24)], electrical conductivity (EC) [wet season (3.33 ± 0.57-12.33 ± 2.51 μS/cm), dry season (5.33 ± 0.57-21.33 ± 2.08 μS/cm)], water temperature [wet season (24.23 ± 0.98-25.40 ± 1.15 °C), dry season (26.20 ± 0.55-27.10 ± 0.75 °C)], TDS [wet season (417.00 ± 15.87-433.33 ± 18.50 mg/L), dry season (319.33 ± 16.50-372.66 ± 22.30 mg/L)], turbidity [wet season (1.01 ± 0.11-2.08 ± 0.99 NTU), dry season (3.11 ± 0.01-5.41 ± 0.24 NTU)], and DO [wet season (2.65 ± 0.37-3.99 ± 0.01 mg/L), dry season (2.12 ± 0.11-2.44 ± 0.01 mg/L)]. For the wet and dry seasons, the water quality indices were 120.225 and 585.015 for River Osolo, 119.849 and 445.751 for River Foreign, 200.474 and 587.833 for Ijoh River, 105.261 and 512.498 for Ole River, and 150.114 and 489.992 for Ole Extension River, respectively. The pH was negatively correlated with DO (r = -0.648), and EC was negatively correlated with DO (r = -0.635). Most of the evaluated parameters were within recommended water safety guidelines. However, the water quality index shows that the water quality was very poor and/or unsuitable for drinking and other domestic uses, especially during the dry season. It is suggested that river water be treated prior to its use for drinking and other domestic purposes.

Assuring quality in high-consequence engineering

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

Hoover, Marcey L.; Kolb, Rachel R.

2014-03-01

In high-consequence engineering organizations, such as Sandia, quality assurance may be heavily dependent on staff competency. Competency-dependent quality assurance models are at risk when the environment changes, as it has with increasing attrition rates, budget and schedule cuts, and competing program priorities. Risks in Sandia's competency-dependent culture can be mitigated through changes to hiring, training, and customer engagement approaches to manage people, partners, and products. Sandia's technical quality engineering organization has been able to mitigate corporate-level risks by driving changes that benefit all departments, and in doing so has assured Sandia's commitment to excellence in high-consequence engineering and national service.

Water quality and small-scale land use mapping in the South-Chinese megacity Guangzhou

NASA Astrophysics Data System (ADS)

Strohschoen, R.; Azzam, R.; Baier, K.

2011-12-01

Since China adopted its "open-door" policy in 1978/ 79, the Pearl River Delta became one of the most rapid and dynamic urbanizing areas in East Asia due to migration, industrialization and globalization processes. The study area Guangzhou grew from a small town to a megacity with some 15 million inhabitants within less than 30 years. The rapid population growth and the urban and industrial expansion led to a remarkably increasing demand for freshwater, a high water consume and a rising sewage production. While economy and house constructions developed very fast, the expansion of water infrastructures could not keep pace with the urban growth. The consequences arising out of these situations are a serious deterioration of the surface and groundwater resources but also a degradation of living conditions and a threat to human health, particularly of the urban poor. In contrast to other studies that often consider the surface water quality outside Guangzhou, our focus was put on the urban Pearl River and its tributaries as well as urban groundwater and tap water. The study was conducted to spatially investigate the present status of the water quality in view of the concurrent formal and informal anthropogenic influences. Additional land use mapping was undertaken to analyze the interrelations between different land use types and water quality and to determine local pollution hotspots which should be taken into particular consideration of future city planning. Supplementing interviews were hold to find out usage patterns of groundwater and strategies to cope with both insufficient tap water quality and water infrastructures. A total of 74 surface water samples and 16 groundwater samples of privately and publicly accessible wells were taken at the beginning of the rainy season in May 2010. Those samples were partly compared to measurements carried out from 2007-2009, where adequate. Further, 15 tap water samples were taken in 2007/ 08 to draw conclusions about possible health risks. The physicochemical parameters (pH, electrical conductivity [μS/ cm], oxygen content [mg/ L], oxygen saturation [%] and redox potential [mV]) were measured in situ or in a 'mobile laboratory'. Chemical mapping which allowed us to evaluate the distribution and concentration of the parameters coliform bacteria, NO3-, NH4+, Cd, Cr, Cu, Pb and Zn was also conducted. The latter were analyzed subject to the standard examination methods stated by the Ministry of Environmental Protection of the People's Republic of China and the U.S. EPA (e.g. ICP-MS). Despite comprehensive improvements in the range of wastewater disposal in recent years, the chemical analysis showed that pollution loads from (informal) housing areas are still very high (especially relating to coliforms). Other main sources of water pollution result from agricultural runoff and animal husbandry. The concentrations of heavy metals by contrast were low which could result from the strengthening of industrial discharge regulations. Based on our findings, qualitative scenarios will be drafted with regard to the interactions of land use, urban expansion and water quality showing vulnerable areas. The findings could be seen as a contribution for an effective and sustainable protection of Guangzhou's land and water resources.

Chemical Analysis and Water Recovery Testing of Shuttle-Mir Humidity Condensate

NASA Technical Reports Server (NTRS)

Mudgett, Paul D.; Straub, John E., II; Schultz, John R.; Sauer, Richard L.; Williams, David E.; Bobe, L. S.; Novikov, V. M.; Andreichouk, P. O.; Protasov, N. N.

1999-01-01

Humidity condensate collected and processed in-flight is an important component of a space station drinking water supply. Water recovery systems in general are designed to handle finite concentrations of specific chemical components. Previous analyses of condensate derived from spacecraft and ground sources showed considerable variation in composition. Consequently, an investigation was conducted to collect condensate on the Shuttle while the vehicle was docked to Mir, and return the condensate to Earth for testing. This scenario emulates an early ISS configuration during a Shuttle docking, because the atmospheres intermix during docking and the condensate composition should reflect that. During the STS-89 and STS-91 flights, a total volume of 50 liters of condensate was collected and returned. Inorganic and organic chemical analyses were performed on aliquots of the fluid. Tests using the actual condensate were then conducted with scaled-down elements of the Russian condensate recovery system to determine the quality of water produced. The composition and test results are described, and implications for ISS are discussed.

Brine reuse in ion-exchange softening: salt discharge, hardness leakage, and capacity tradeoffs.

PubMed

Flodman, Hunter R; Dvorak, Bruce I

2012-06-01

Ion-exchange water softening results in the discharge of excess sodium chloride to the aquatic environment during the regeneration cycle. In order to reduce sodium chloride use and subsequent discharge from ion-exchange processes, either brine reclaim operations can be implemented or salt application during regeneration can be reduced. Both result in tradeoffs related to loss of bed volumes treated per cycle and increased hardness leakage. An experimentally validated model was used to compare concurrent water softening operations at various salt application quantities with and without the direct reuse of waste brine for treated tap water of typical midwestern water quality. Both approaches were able to reduce salt use and subsequent discharge. Reducing salt use and discharge by lowering the salt application rate during regeneration consequently increased hardness leakage and decreased treatment capacity. Single or two tank brine recycling systems are capable of reducing salt use and discharge without increasing hardness leakage, although treatment capacity is reduced.

[A study of groundwater contamination with organic fuels and potential public health impact in Itaguaí, Rio de Janeiro State, Brazil].

PubMed

Silva, Rosimar Lima Brandão; Barra, Cristina Maria; Monteiro, Teófilo Carlos do Nascimento; Brilhante, Ogenis Magno

2002-01-01

Increasing attention is current focused on urban groundwater contamination with gasoline hydrocarbon compounds in Brazil. The compounds benzene, toluene, ethylbenzene, and xylenes (BTEX) contained in fuels are highly toxic and can have severe public health consequences, besides posing the risk of intake from the water table by way of contamination. After two years of a steady gasoline storage tank leak, water samples from private household wells in the district of Brisa Mar, Itaguaí, Rio de Janeiro State, were analyzed and the concentration of BTEX compounds was evaluated. Two out of ten water samples from the study area presented BTEX concentrations above the National Water Quality Standard (Brazilian Health Ministry Ruling No. 1469/2000), in which the maximum permissible benzene concentration is 5 micro g.L-1. Four others wells were also contaminated with nitrate, responsible for the induction of methemoglobinemia. Natural attenuation (intrinsic biodegradation) mechanisms through electron acceptors was also investigated in this study.

A livelihood in a risky environment: Farmers' preferences for irrigation with wastewater in Hyderabad, India.

PubMed

Saldías, Cecilia; Speelman, Stijn; Drechsel, Pay; Van Huylenbroeck, Guido

2017-04-01

Most cities in developing countries fail to treat their wastewater comprehensively. Consequently, farmers downstream use poor-quality water for irrigation. This practice implies risks for farmers, consumers and the environment. Conversely, this water supply supports the livelihood of these farmers and other stakeholders along the value chains. Linking safer options for wastewater management with irrigation could therefore be a win-win solution: removing the risks for society and maintaining the benefits for farmers. However, in developing countries, the high investment costs for the required treatment are problematic and the willingness of farmers to pay for the water (cost recovery) is often questionable. Using a choice experiment, this paper gives insight into farmers' preferences for wastewater use scenarios, quantifying their willingness to pay. The case study is Hyderabad, India. Farmers there prefer water treatment and are prepared to pay a surplus for this. Considering the cost-recovery challenge, this information could be valuable for planning small on site wastewater treatment systems.

Reconnaissance of the chemical quality of surface waters of the Neches River basin, Texas

USGS Publications Warehouse

Hughes, Leon S.; Leifeste, Donald K.

1967-01-01

The kinds and quantities of minerals dissolved in the surface water of the Neches River basin result from such environmental factors as geology, streamflow patterns and characteristics, and industrial influences. As a result of high rainfall in the basin, much of the readily soluble material has been leached from the surface rocks and soils. Consequently, the water in the streams is usually low in concentrations of dissolved minerals and meets the U.S. Public Health Service drinking-water standards. In most streams the concentration of dissolved solids is less than 250 ppm (parts per million). The Neches River drains an area of about 10,000 square miles in eastern Texas. From its source in southeast Van Zandt County the river flows in a general southeasterly direction and empties into Sabine Lake, an arm of the Gulf of Mexico. In the basin the climate ranges from moist subhumid to humid, and the average annual rainfall ranges from 46 inches is the northwest to more than 52 inches in the southeast. Annual runoff from the basin has averaged 11 inches; however, runoff rates vary widely from year to year. The yearly mean discharge of the Neches River at Evadale has ranged from 994 to 12,720 cubic feet per second. The rocks exposed in the Neches River basin are of the Quaternary and Tertiary Systems and range in age from Eocene to Recent. Throughout most of the basin the geologic formations dip generally south and southeast toward the gulf coast. The rate of dip is greater than that of the land surface; and as a result, the older formations crop out to the north of the younger formations. Water from the outcrop areas of the Wilcox Group and from the older formations of the Claiborne Group generally has dissolved-solids concentrations ranging from 100 to 250 ppm; water from the younger formations has concentrations less than 100 ppm. The northern half of the basin has soft water, with less than 60 ppm hardness. The southern half of .the basin has very soft water, usually with less than 30 ppm hardness. The chloride concentrations are less than 20 ppm in surface water in the southern half of the basin and usually range from 20 to 100 ppm in the northern half of the basin. Concentrations greater than 100 ppm are found only where pollution is occurring. The Neches River basin has an abundance of surface water, but uneven distribution of runoff makes storage projects necessary to provide dependable water supplies. The principal existing reservoirs, with the exception of Striker Creek Reservoir, contain water of excellent quality. Chemical-quality data for the Striker Creek drainage area indicate that its streams are affected by .the disposal of brines associated with oil production. Sam Rayburn Reservoir began impounding water in 1965. The water impounded should prove of acceptable quality for most uses, but municipal and industrial wastes released into the Angelina River near Lufkin may have a degrading effect on the quality of the water, especially during extended periods of low flows. Water available for storage at the many potential reservoir sites will be of good quality; but, if the proposed salt-water barrier is to impound acceptable water, the disposal of oilfield brine into Pine Island Bayou should be discontinued.

A deformable surface model for real-time water drop animation.

PubMed

Zhang, Yizhong; Wang, Huamin; Wang, Shuai; Tong, Yiying; Zhou, Kun

2012-08-01

A water drop behaves differently from a large water body because of its strong viscosity and surface tension under the small scale. Surface tension causes the motion of a water drop to be largely determined by its boundary surface. Meanwhile, viscosity makes the interior of a water drop less relevant to its motion, as the smooth velocity field can be well approximated by an interpolation of the velocity on the boundary. Consequently, we propose a fast deformable surface model to realistically animate water drops and their flowing behaviors on solid surfaces. Our system efficiently simulates water drop motions in a Lagrangian fashion, by reducing 3D fluid dynamics over the whole liquid volume to a deformable surface model. In each time step, the model uses an implicit mean curvature flow operator to produce surface tension effects, a contact angle operator to change droplet shapes on solid surfaces, and a set of mesh connectivity updates to handle topological changes and improve mesh quality over time. Our numerical experiments demonstrate a variety of physically plausible water drop phenomena at a real-time rate, including capillary waves when water drops collide, pinch-off of water jets, and droplets flowing over solid materials. The whole system performs orders-of-magnitude faster than existing simulation approaches that generate comparable water drop effects.

The public health significance of trace chemicals in waste water utilization

PubMed Central

Shuval, Hillel I.

1962-01-01

The practice of waste water utilization has grown considerably in recent years, owing to the growing demand for water for agricultural, industrial and domestic purposes. Such utilization presents certain problems in respect of the quality of the reclaimed water, on account of the presence of certain trace chemicals in the waste waters to be re-used. The presence of these trace chemicals may have important consequences in the agricultural or industrial utilization of waste waters, but from the public health point of view it is in the re-use of waste waters for domestic purposes that their presence has most importance, owing to their possible toxic effects. This paper discusses the public health significance of trace chemicals in water, with special reference to some of the newer complex synthetic organic compounds that are appearing in ever-increasing numbers in industrial wastes. Current information on the acute and chronic toxicity of these substances is reviewed and related to possible methods of treatment of waste waters. In conclusion, the author points out that the problem of trace chemicals is not confined only to direct waste-water reclamation projects, but arises in all cases where surface waters polluted with industrial wastes are used as a source of domestic supply. PMID:13988826

Contamination of ground water as a consequence of land disposal of dye waste mixed sewage effluents: a case study of Panipat district of Haryana, India.

PubMed

Dubey, S K; Yadav, Rashmi; Chaturvedi, R K; Yadav, R K; Sharma, V K; Minhas, P S

2010-09-01

Spatial samples of surface and ground water collected from land disposal site of dye waste mixed sewage effluents at Binjhole, in Haryana, India were analyzed to evaluate its effect on quality of pond, hand pumps and ground waters for human health and irrigation purposes. It was found that average COD and TDS of dye houses discharge (310 and 3,920 mg/L) and treated sewage (428 and 1,470 mg/L) on mixing acquired the values of 245 and 1,780 mg/L and only Pb (0.24 microg/L) was above the permissible limit for irrigation purpose. Disposal of this mixed water to village pond changes the COD and TDS to 428 and 1,470 mg/L, respectively. COD and TDS of hand pump water samples were 264 and 1,190 mg/L, where as in tube well water these values were 151 and 900 mg/L. Though the ground water contamination seemed to decrease with the increasing distance from the pond but COD, TDS and BOD values continued to be quite high in water samples drawn from the hand pumps up to a distance of 500 m from pond. However, the major cause of the concern in these waters was Pb (0.11-0.45 ppm). Crops grown with this water shows accumulation of heavy metals like Pb,Cd, Fe, Mn, Ni, Cu, and Zn but in few crops they (Zn, Pb and Cd) exceed the safe limits. Regular consumption of these crop products may lead heavy metal toxicity. It was concluded from this study that the deep seepage of effluents led to deterioration of ground water quality for drinking purposes and the well waters rendered unfit for irrigation purposes within a span of 2 years. This warrants appropriate disposal measures for sewage and dye industry effluents in order to prevent deterioration of ground water and health of human and animals.

Real time high frequency monitoring of water quality in river streams using a UV-visible spectrometer: interest, limits and consequences for monitoring strategies

NASA Astrophysics Data System (ADS)

Faucheux, Mikaël; Fovet, Ophélie; Gruau, Gérard; Jaffrézic, Anne; Petitjean, Patrice; Gascuel-Odoux, Chantal; Ruiz, Laurent

2013-04-01

Stream water chemistry is highly variable in space and time, therefore high frequency water quality measurement methods are likely to lead to conceptual advances in the hydrological sciences. Sub-daily data on water quality improve the characterization of pollutant sources and pathways during flood events as well as during long-term periods [1]. However, real time, high frequency monitoring devices needs to be properly calibrated and validated in real streams. This study analyses data from in situ monitoring of a stream water quality. During two hydrological years (2010-11, 2011-12), a submersible UV-visible spectrometer (Scan Spectrolyser) was used for surface water quality measurement at the outlet of a headwater catchment located at Kervidy-Naizin, Western France (AgrHys long-term hydrological observatory, http://www.inra.fr/ore_agrhys/). The spectrometer is reagentless and equipped with an auto-cleaning system. It allows real time, in situ and high frequency (20 min) measurements and uses a multiwavelengt spectral (200-750 nm) for simultaneous measurement of nitrate, dissolved organic carbon (DOC) and total suspended solids (TSS). A global calibration based on a PLS (Partial Least Squares) regression is provided by the manufacturer as default configuration of the UV-visible spectrometer. We carried out a local calibration of the spectrometer based on nitrates and DOC concentrations analysed in the laboratory from daily manual sampling and sub-daily automatic sampling of flood events. TSS results are compared with 15 min turbidity records from a continuous turdidimeter (Ponsel). The results show a good correlation between laboratory data and spectrometer data both during basis flows periods and flood events. However, the local calibration gives better results than the global one. Nutrient fluxes estimates based on high and different low frequency time series (daily to monthly) are compared to discuss the implication for environmental monitoring strategies. Such monitoring methods can therefore be interesting for designing monitoring strategy of environmental observatory and provide dense time series likely to highlight patterns or trends using appropriate approaches such as spectral analysis [2]. 1. Wade, A.J. et al., HESS Discuss., 2012. 9(5), p.6458- 6506. 2. Aubert, A. et al., submitted to EGU 2013-4745 vol. 15.

A one-dimensional, steady-state, dissolved-oxygen model and waste-load assimilation study for Duck Creek, Madison, Tipton, and Hamilton counties, Indiana

USGS Publications Warehouse

Crawford, Charles G.; Wilber, William G.; Peters, James G.

1980-01-01

The Indiana State Board of Health is developing a State water-quality plan that includes establishing limits for wastewater effluents discharged into Indiana streams. A digital model calibrated to conditions in Duck Creek was used to develop alternatives for future waste loadings that would be compatible with Indiana stream water-quality standards defined for two critical hydrologic conditions, summer and winter low flows. The major point-source waste load affecting Duck Creek is the Elwood wastewater-treatment facility. Natural streamflow during the low flow is zero, so no benefit from dilution is provided. Natural reaeration at the low-flow condition (approximately 3 cubic feet per second), also low, is estimated to be less than 1 per day (base e at 20 Celsius). Consequently, the wasteload assimilative capacity of the stream is low. Effluent ammonia-nitrogen concentrations, projected by the Indiana State Board of Health, will result in stream ammonia-nitrogen concentrations that exceed the State ammonia-nitrogen toxicity standards (2.5 milligrams per liter from April to October and 4.0 milligrams per liter from November through March). The projected effluent ammonia-nitrogen load will also result in the present Indiana stream dissolved-oxygen standard (5.0 milligrams per liter) not being met. Benthic-oxygen demand may also affect stream water quality. During the summer low-flow, a benthic-oxygen demand of only 0.6 gram per square meter per day would utilize all the streams 's available assimilative capacity. (USGS)

Summary and trend analysis of water-quality data for the Oakes Test Area, southeastern North Dakota, 1984-2004

USGS Publications Warehouse

Ryberg, Karen R.

2007-01-01

The Oakes Test Area is operated and maintained by the Garrison Diversion Conservancy District, under a cooperative agreement with the Bureau of Reclamation, to evaluate the effectiveness and environmental consequences of irrigation. As part of the evaluation, the Bureau of Reclamation collected water-quality samples from seven sites on the James River and the Oakes Test Area. The data were summarized and examined for trends in concentration. A nonparametric statistical test was used to test whether each concentration was increasing or decreasing with time for selected physical properties and constituents, and a trend slope was estimated for each constituent at each site. Trends were examined for two time periods, 1988-2004 and 1994-2004. Results varied by site and by constituent. All sites and all constituents tested had at least one statistically significant trend in the period 1988-2004. Sulfate, total dissolved solids, nitrate, and orthophosphate have significant positive trends at multiple sites with no significant negative trend at any site. Alkalinity and arsenic have single significant positive trends. Hardness, calcium, magnesium, sodium, sodium-adsorption ratio, potassium, and chloride have both significant positive and negative trends. Ammonia has a single significant negative trend. Fewer significant trends were identified in 1994-2004, and all but one were positive. The contribution to the James River from Oakes Test Area drainage appears to have little effect on water quality in the James River.

Health Effects of Energy Resources

USGS Publications Warehouse

Orem, William; Tatu, Calin; Pavlovic, Nikola; Bunnell, Joseph; Kolker, Allan; Engle, Mark; Stout, Ben

2010-01-01

Energy resources (coal, oil, and natural gas) are among the cornerstones of modern industrial society. The exploitation of these resources, however, is not without costs. Energy materials may contain harmful chemical substances that, if mobilized into air, water, or soil, can adversely impact human health and environmental quality. In order to address the issue of human exposure to toxic substances derived from energy resources, the U.S. Geological Survey (USGS) Energy Resources Program developed a project entitled 'Impacts of Energy Resources on Human Health and Environmental Quality.' The project is intended to provide policymakers and the public with the scientific information needed to weigh the human health and environmental consequences of meeting our energy needs. This fact sheet discusses several areas where the USGS Energy Resources Program is making scientific advances in this endeavor.

On-Line Monitoring of Escherichia coli in Raw Water at Oset Drinking Water Treatment Plant, Oslo (Norway)

PubMed Central

Tryland, Ingun; Eregno, Fasil Ejigu; Braathen, Henrik; Khalaf, Goran; Sjølander, Ingrid; Fossum, Marie

2015-01-01

The fully automated Colifast ALARMTM has been used for two years for daily monitoring of the presence/absence of Escherichia coli in 100 mL raw water at Oset drinking water treatment plant in Oslo, Norway. The raw water is extracted from 35 m depth from the Lake Maridalsvannet. E. coli was detected in 18% of the daily samples. In general, most samples positive for E. coli were observed during the autumn turnover periods, but even in some samples taken during warm and dry days in July, with stable temperature stratification in the lake, E. coli was detected. The daily samples gave useful additional information compared with the weekly routine samples about the hygienic raw water quality and the hygienic barrier efficiency of the lake under different weather conditions and seasons. The winter 2013/2014 was much warmer than the winter 2012/2013. The monitoring supported the hypothesis that warmer winters with shorter periods with ice cover on lakes, which may be a consequence of climate changes, may reduce the hygienic barrier efficiency in deep lakes used as drinking water sources. PMID:25658685

Environmental and socio-economic methodologies and solutions towards integrated water resources management.

PubMed

Friesen, Jan; Rodriguez Sinobas, Leonor; Foglia, Laura; Ludwig, Ralf

2017-03-01

Semi-arid regions are facing the challenge of managing water resources under conditions of increasing scarcity and drought. These are recently pressured by the impact of climate change favoring the shifting from using surface water to groundwater without taking sustainability issues into account. Likewise, water scarcity raises the competition for water among users, increasing the risk of social conflicts, as the availability of fresh water in sufficient quality and quantity is already one of the major factors limiting socio-economic development. In terms of hydrology, semi-arid regions are characterized by very complex hydro- and hydrogeological systems. The complexity of the water cycle contrasts strongly with the poor data availability, (1) which limits the number of analysis techniques and methods available to researchers, (2) limits the accuracy of models and predictions, and (3) consequently challenges the capabilities to develop appropriate management measures to mitigate or adapt the environment to scarcity and drought conditions. Integrated water resources management is a holistic approach to focus on both environmental as well as on socio-economic factors influencing water availability and supply. The management approaches and solutions adopted, e.g. in form of decision support for specific water resources systems, are often highly specific for individual case studies. Copyright © 2016 Elsevier B.V. All rights reserved.

Faecal contamination of drinking water in a Brazilian shanty town: importance of household storage and new human faecal marker testing.

PubMed

Copeland, Curtis C; Beers, Benjamin B; Thompson, Meghan R; Fitzgerald, Relana P; Barrett, Leah J; Sevilleja, Jesus E; Alencar, Sayonara; Lima, Aldo A M; Guerrant, Richard L

2009-06-01

Worldwide, contaminated drinking water poses a major health threat, particularly to child development. Diarrhoea represents a large part of the water-related disease burden and enteric infections have been linked to nutritional and growth shortfalls as well as long-term physical and cognitive impairment in children. Previous studies detailed the frequency of infection and the consequences for child health in a shanty town in north-east Brazil. To determine the frequency of contaminated water, we measured faecal contamination in primary drinking water samples from 231 randomly selected households. Risk for contamination was compared across source and storage types. Nearly a third of the study households (70/231: 30.3%) had contaminated drinking water; the source with the highest frequency of contamination was well water (23/24: 95.8%). For tap water, the type of storage had a significant effect on the susceptibility to contamination (chi(2) = 12.090; p = 0.007). The observed pattern of contamination demonstrated the relative potential contributions of both source and storage. With evidence that supports the inclusion of source and storage in water quality surveys, this study, like others, suggests that contaminated drinking water in storage vessels may be an important factor for the documented diarrhoea disease burden in the Brazilian shanty town.

Water management in Egypt for facing the future challenges

PubMed Central

Omar, Mohie El Din M.; Moussa, Ahmed M.A.

2016-01-01

The current water shortage in Egypt is 13.5 Billion cubic meter per year (BCM/yr) and is expected to continuously increase. Currently, this water shortage is compensated by drainage reuse which consequently deteriorates the water quality. Therefore, this research was commenced with the objective of assessing different scenarios for 2025 using the Water Evaluation and Planning (WEAP) model and by implementing different water sufficiency measures. Field data were assembled and analyzed, and different planning alternatives were proposed and tested in order to design three future scenarios. The findings indicated that water shortage in 2025 would be 26 BCM/yr in case of continuation of current policies. Planning alternatives were proposed to the irrigation canals, land irrigation timing, aquatic weeds in waterways and sugarcane areas in old agricultural lands. Other measures were suggested to pumping rates of deep groundwater, sprinkler and drip irrigation systems in new agricultural lands. Further measures were also suggested to automatic daily surveying for distribution leak and managing the pressure effectively in the domestic and industrial water distribution systems. Finally, extra measures for water supply were proposed including raising the permitted withdrawal limit from deep groundwater and the Nubian aquifer and developing the desalination resource. The proposed planning alternatives would completely eliminate the water shortage in 2025. PMID:27222745

Water management in Egypt for facing the future challenges.

PubMed

Omar, Mohie El Din M; Moussa, Ahmed M A

2016-05-01

The current water shortage in Egypt is 13.5 Billion cubic meter per year (BCM/yr) and is expected to continuously increase. Currently, this water shortage is compensated by drainage reuse which consequently deteriorates the water quality. Therefore, this research was commenced with the objective of assessing different scenarios for 2025 using the Water Evaluation and Planning (WEAP) model and by implementing different water sufficiency measures. Field data were assembled and analyzed, and different planning alternatives were proposed and tested in order to design three future scenarios. The findings indicated that water shortage in 2025 would be 26 BCM/yr in case of continuation of current policies. Planning alternatives were proposed to the irrigation canals, land irrigation timing, aquatic weeds in waterways and sugarcane areas in old agricultural lands. Other measures were suggested to pumping rates of deep groundwater, sprinkler and drip irrigation systems in new agricultural lands. Further measures were also suggested to automatic daily surveying for distribution leak and managing the pressure effectively in the domestic and industrial water distribution systems. Finally, extra measures for water supply were proposed including raising the permitted withdrawal limit from deep groundwater and the Nubian aquifer and developing the desalination resource. The proposed planning alternatives would completely eliminate the water shortage in 2025.

Climate and Humans as Amplifiers of Hydro-Ecologic Change: Science and Policy Implications for Intensively Managed Landscapes

NASA Astrophysics Data System (ADS)

Foufoula-Georgiou, E.; Czuba, J. A.; Belmont, P.; Wilcock, P. R.; Gran, K. B.; Kumar, P.

2015-12-01

Climatic trends and agricultural intensification in Midwestern U.S. landscapes has contributed to hydrologic regime shifts and a cascade of changes to water quality and river ecosystems. Informing management and policy to mitigate undesired consequences requires a careful scientific analysis that includes data-based inference and conceptual/physical modeling. It also calls for a systems approach that sees beyond a single stream to the whole watershed, favoring the adoption of minimal complexity rather than highly parameterized models for scenario evaluation and comparison. Minimal complexity models can focus on key dynamic processes of the system of interest, reducing problems of model structure bias and equifinality. Here we present a comprehensive analysis of climatic, hydrologic, and ecologic trends in the Minnesota River basin, a 45,000 km2 basin undergoing continuous agricultural intensification and suffering from declining water quality and aquatic biodiversity. We show that: (a) it is easy to arrive at an erroneous view of the system using traditional analyses and modeling tools; (b) even with a well-founded understanding of the key drivers and processes contributing to the problem, there are multiple pathways for minimizing/reversing environmental degradation; and (c) addressing the underlying driver of change (i.e., increased streamflows and reduced water storage due to agricultural drainage practices) by restoring a small amount of water storage in the landscape results in multiple non-linear improvements in downstream water quality. We argue that "optimization" between ecosystem services and economic considerations requires simple modeling frameworks, which include the most essential elements of the whole system and allow for evaluation of alternative management scenarios. Science-based approaches informing management and policy are urgent in this region calling for a new era of watershed management to new and accelerating stressors at the intersection of the food-water-energy-environment nexus.

Modeling hydrodynamics, water temperature, and water quality in the Klamath River upstream of Keno Dam, Oregon, 2006-09

USGS Publications Warehouse

Sullivan, Annett B.; Rounds, Stewart A.; Deas, Michael L.; Asbill, Jessica R.; Wellman, Roy E.; Stewart, Marc A.; Johnston, Matthew W.; Sogutlugil, I. Ertugrul

2011-01-01

A hydrodynamic, water temperature, and water-quality model was constructed for a 20-mile reach of the Klamath River downstream of Upper Klamath Lake, from Link River to Keno Dam, for calendar years 2006-09. The two-dimensional, laterally averaged model CE-QUAL-W2 was used to simulate water velocity, ice cover, water temperature, specific conductance, dissolved and suspended solids, dissolved oxygen, total nitrogen, ammonia, nitrate, total phosphorus, orthophosphate, dissolved and particulate organic matter, and three algal groups. The Link-Keno model successfully simulated the most important spatial and temporal patterns in the measured data for this 4-year time period. The model calibration process provided critical insights into water-quality processes and the nature of those inputs and processes that drive water quality in this reach. The model was used not only to reproduce and better understand water-quality conditions that occurred in 2006-09, but also to test several load-reduction scenarios that have implications for future water-resources management in the river basin. The model construction and calibration process provided results concerning water quality and transport in the Link-Keno reach of the Klamath River, ranging from interesting circulation patterns in the Lake Ewauna area to the nature and importance of organic matter and algae. These insights and results include: * Modeled segment-average water velocities ranged from near 0.0 to 3.0 ft/s in 2006 through 2009. Travel time through the model reach was about 4 days at 2,000 ft3/s and 12 days at 700 ft3/s flow. Flow direction was aligned with the upstream-downstream channel axis for most of the Link-Keno reach, except for Lake Ewauna. Wind effects were pronounced at Lake Ewauna during low-flow conditions, often with circulation in the form of a gyre that rotated in a clockwise direction when winds were towards the southeast and in a counterclockwise direction when winds were towards the northwest. * Water temperatures ranged from near freezing in winter to near 30 degrees C at some locations and periods in summer; seasonal water temperature patterns were similar at the inflow and outflow. Although vertical temperature stratification was not present at most times and locations, weak stratification could persist for periods up to 1-2 weeks, especially in the downstream parts of the reach. Thermal stratification was important in controlling vertical variations in water quality. * The specific conductance, and thus density, of tributaries within the reach usually was higher than that of the river itself, so that inflows tended to sink below the river surface. This was especially notable for inflows from the Klamath Straits Drain, which tended to sink to the bottom of the Klamath River at its confluence and not mix vertically for several miles downstream. * The model was able to capture most of the seasonal changes in the algal population by modeling that population with three algal groups: blue-green algae, diatoms, and other algae. The blooms of blue-green algae, consisting mostly of Aphanizomenon flos aquae that entered from Upper Klamath Lake, were dominant, dwarfing the populations of the other two algae groups in summer. A large part of the blue-green algae population that entered this reach from upstream tended to settle out, die, and decompose, especially in the upper part of the Link-Keno reach. Diatoms reached a maximum in spring and other algae in midsummer. * Organic matter, occurring in both dissolved and particulate forms, was critical to the water quality of this reach of the Klamath River, and was strongly tied to nutrient and dissolved-oxygen dynamics. Dissolved and particulate organic matter were subdivided into labile (quickly decaying) and refractory (slowing decaying) groups for modeling purposes. The particulate matter in summer, consisting largely of dead blue-green algae, decayed quickly. Consequently, this particulate matt

Opportunities for woody crop production using treated wastewater in Egypt. I. Afforestation strategies.

PubMed

Zalesny, Ronald S; Stanturf, John A; Evett, Steven R; Kandil, Nabil F; Sorianos, Chris

2011-01-01

The Nile River provides nearly 97% of Egypt's freshwater supply. Egypt's share of Nile waters is fixed at 55.5 billion cubic meters annually. As a result, Egypt will not be able to meet increasing water demand using freshwater from the Nile and has been developing non-conventional wastewater reuse strategies to meet future demands. The USAID Mission in Cairo began promoting strategies for water reuse in 2004, and guidelines for safe and direct reuse of treated wastewater for agricultural purposes were approved in 2005 (Egyptian Code 501/2005). Twenty-four man-made forests were established that have been useful for assessing the efficacy of using treated wastewater for afforestation. At present, approximately 4,340 hectares are under irrigation with treated wastewater, utilizing a total daily volume of 467,400 cubic meters. Wastewater has been applied to trees along roads, greenbelts in cities, and woody production systems. Currently, a joint USDA Forest Service--Agricultural Research Service technical assistance team has been evaluating the feasibility of scaling up such afforestation efforts throughout Egypt. We describe information about: 1) suitable tree species that have been identified based on local soil characteristics, water quality, and quantity of water supply; 2) the benefits and consequences of using these species; 3) strategies to maximize the potential of afforestation with regard to improving water quality, maximizing resource production, increasing biodiversity, and limiting commercial inputs; and 4) potential long-term impacts on the natural resource base from afforestation. A companion paper addresses irrigation recommendations based on species and local conditions (see Evett et al. 2000).

Artificial Post mining lakes - a challenge for the integration in natural hydrography and river basin management

NASA Astrophysics Data System (ADS)

Fleischhammel, Petra; Schoenheinz, Dagmar; Grünewald, Uwe

2010-05-01

In terms of the European Water Framework Directive (WFD), post mining lakes are artificial water bodies (AWB). The sustainable integration of post mining lakes in the groundwater and surface water landscape and their consideration in river basin management plans have to be linked with various (geo)hydrological, hydro(geo)chemical, technological and socioeconomic issues. The Lower Lusatian lignite mining district in eastern Germany is part of the major river basins of river Elbe and river Oder. Regionally, the mining area is situated in the sub-basins of river Spree and Schwarze Elster. After the cessation of mining activities and thereby of the artificially created groundwater drawdown in numerous mining pits, a large number of post mining lakes are evolving as consequence of natural groundwater table recovery. The lakes' designated uses vary from water reservoirs to landscape, recreation or fish farming lakes. Groundwater raise is not only substantial for the lake filling, but also for the area rehabilitation and a largely self regulated water balance in post mining landscapes. Since the groundwater flow through soil and dump sites being affected by the former mining activities, groundwater experiences various changes in its hydrochemical properties as e.g. mineralization and acidification. Consequently, downstream located groundwater fed running and standing water bodies will be affected too. Respective the European Water Framework Directive, artificial post mining lakes are not allowed to cause significant adverse impacts on the good ecological status/potential of downstream groundwater and surface water bodies. The high sulphate concentrations of groundwater fed mining lakes which reach partly more than 1,000 mg/l are e.g. damaging concrete constructures in downstream water bodies thereby representing threats for hydraulic facilities and drinking water supply. Due to small amounts of nutrients, the lakes are characterised by oligo¬trophic to slightly mesotrophic conditions. The aquatic flora and fauna are limited to a few well adapted species. Therefore, the issue of hydrochemical constitution of the lakes' waters becomes more and more relevant. The prediction of water quality development in post mining lakes is a key requirement to regulate and manage the later hydrochemical conditions. Initially, this prediction was made by individual case studies for single lakes. By means of an iterative research process during the last years, hydrochemical lake models were developed as prediction tools, which allow a complex processing of interconnected post mining lakes and their integration in natural hydrography with respect to quantitative and qualitative evaluation. To counteract the poor water quality of mining lakes, flooding by surface water from neighbouring river basins, e.g. the river Neisse, shall support a quicker and thereby hydrochemically less damaging lake filling. However, this external flooding is only feasible under conditions of high runoff and therefore only as intermitted practice applicable. Additionally, technological measures of water treatment have to be applied to achieve the required effluent quality and to ensure the designated use. Regrettably, these technologies aren't commercially standard up to now and are not sustainable, while flooding or provides a huge amount itself of positive potential for hydrochemical stabilization. The river basin management of the rivers Spree and Schwarze Elster is attended by a common working group of the Federal States of Brandenburg and Berlin as well as the Free State of Saxony. The quantitative distribution of the regionally available water considers the potential use for drinking water supply, process water, …, and the flooding of open-pits. However, due to the formulated rank order, the flooding of the numerous mining open pits in Lusatia is on the last position. To guarantee a reliable flooding and a continuous water supply of the post mining lakes, additional water resources have to exploited. Additionally, the prospected climate induced changes in water supply have to be taken into account for a sustainable integrated water resources management in the Lusatian post-mining district.

Assessment of turkey vehicle container microclimate on transit during summer season conditions

NASA Astrophysics Data System (ADS)

Carvalho, Rafael H.; Honorato, Danielle C. B.; Guarnieri, Paulo D.; Soares, Adriana L.; Pedrão, Mayka R.; Oba, Alexandre; Paião, Fernanda G.; Ida, Elza I.; Shimokomaki, Massami

2018-06-01

This study evaluated the formed microclimate commercial truck transport practices effects on the turkeys' welfare by measuring Dead on Arrival (DOA) index and pale, soft, and exudative (PSE-like) meat occurrence. The experimental design was entirely randomized in a 6 × 2 factorial arrangements (two truck container compartments × six water shower groups) with birds positioned at superior front (SF), inferior front (IF), superior middle (SM), inferior middle (IM), superior rear (SR), and inferior rear (IR) and two bath treatments: with water shower (WiS) and without water shower (WoS) with eight replications for each treatment. The animals were transported for 95 min' journey from the farm to the slaughterhouse under hot-humidity conditions. The results shown herein indicated the formation of a thermal core at the inferior middle and rear truck container regions, because the heat produced by the birds and the influence of developed microclimate consisting of temperature, relative humidity, and air ventilation. The IM and IR container compartments under the WoS treatment presented the highest ( P < 0.01) numbers of PSE-like meat incidence and DOA index values compared with those located at the front under WiS treatment as the consequence of the altered to birds unbearable conditions within the container microclimate in transit. The formed microclimate during the commercial transport practices under hot-humidity conditions affected the bird's welfare consequently turkey meat qualities.

Assessment of turkey vehicle container microclimate on transit during summer season conditions

NASA Astrophysics Data System (ADS)

Carvalho, Rafael H.; Honorato, Danielle C. B.; Guarnieri, Paulo D.; Soares, Adriana L.; Pedrão, Mayka R.; Oba, Alexandre; Paião, Fernanda G.; Ida, Elza I.; Shimokomaki, Massami

2018-01-01

This study evaluated the formed microclimate commercial truck transport practices effects on the turkeys' welfare by measuring Dead on Arrival (DOA) index and pale, soft, and exudative (PSE-like) meat occurrence. The experimental design was entirely randomized in a 6 × 2 factorial arrangements (two truck container compartments × six water shower groups) with birds positioned at superior front (SF), inferior front (IF), superior middle (SM), inferior middle (IM), superior rear (SR), and inferior rear (IR) and two bath treatments: with water shower (WiS) and without water shower (WoS) with eight replications for each treatment. The animals were transported for 95 min' journey from the farm to the slaughterhouse under hot-humidity conditions. The results shown herein indicated the formation of a thermal core at the inferior middle and rear truck container regions, because the heat produced by the birds and the influence of developed microclimate consisting of temperature, relative humidity, and air ventilation. The IM and IR container compartments under the WoS treatment presented the highest (P < 0.01) numbers of PSE-like meat incidence and DOA index values compared with those located at the front under WiS treatment as the consequence of the altered to birds unbearable conditions within the container microclimate in transit. The formed microclimate during the commercial transport practices under hot-humidity conditions affected the bird's welfare consequently turkey meat qualities.

Assessment of turkey vehicle container microclimate on transit during summer season conditions.

PubMed

Carvalho, Rafael H; Honorato, Danielle C B; Guarnieri, Paulo D; Soares, Adriana L; Pedrão, Mayka R; Oba, Alexandre; Paião, Fernanda G; Ida, Elza I; Shimokomaki, Massami

2018-06-01

This study evaluated the formed microclimate commercial truck transport practices effects on the turkeys' welfare by measuring Dead on Arrival (DOA) index and pale, soft, and exudative (PSE-like) meat occurrence. The experimental design was entirely randomized in a 6 × 2 factorial arrangements (two truck container compartments × six water shower groups) with birds positioned at superior front (SF), inferior front (IF), superior middle (SM), inferior middle (IM), superior rear (SR), and inferior rear (IR) and two bath treatments: with water shower (WiS) and without water shower (WoS) with eight replications for each treatment. The animals were transported for 95 min' journey from the farm to the slaughterhouse under hot-humidity conditions. The results shown herein indicated the formation of a thermal core at the inferior middle and rear truck container regions, because the heat produced by the birds and the influence of developed microclimate consisting of temperature, relative humidity, and air ventilation. The IM and IR container compartments under the WoS treatment presented the highest (P < 0.01) numbers of PSE-like meat incidence and DOA index values compared with those located at the front under WiS treatment as the consequence of the altered to birds unbearable conditions within the container microclimate in transit. The formed microclimate during the commercial transport practices under hot-humidity conditions affected the bird's welfare consequently turkey meat qualities.

Optimal city size and population density for the 21st century.

PubMed

Speare A; White, M J

1990-10-01

The thesis that large scale urban areas result in greater efficiency, reduced costs, and a better quality of life is reexamined. The environmental and social costs are measured for different scales of settlement. The desirability and perceived problems of a particular place are examined in relation to size of place. The consequences of population decline are considered. New York city is described as providing both opportunities in employment, shopping, and cultural activities as well as a high cost of living, crime, and pollution. The historical development of large cities in the US is described. Immigration has contributed to a greater concentration of population than would have otherwise have occurred. The spatial proximity of goods and services argument (agglomeration economies) has changed with advancements in technology such as roads, trucking, and electronic communication. There is no optimal city size. The overall effect of agglomeration can be assessed by determining whether the markets for goods and labor are adequate to maximize well-being and balance the negative and positive aspects of urbanization. The environmental costs of cities increase with size when air quality, water quality, sewage treatment, and hazardous waste disposal is considered. Smaller scale and lower density cities have the advantages of a lower concentration of pollutants. Also, mobilization for program support is easier with homogenous population. Lower population growth in large cities would contribute to a higher quality of life, since large metropolitan areas have a concentration of immigrants, younger age distributions, and minority groups with higher than average birth rates. The negative consequences of decline can be avoided if reduction of population in large cities takes place gradually. For example, poorer quality housing can be removed for open space. Cities should, however, still attract all classes of people with opportunities equally available.

Cusiana trend exploration, Llanos foothills, Colombia - The opening of a new hydrocarbon province

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

Hayward, A.B.; Addison, F.T.; O`Leary, J.

1996-08-01

The discovery of the Cusiana field in 1992 followed 30 years of exploration in the Llanos fold and thrust belt of Colombia. Early exploration activity focused on large surface anticlines that were all fresh water flushed - a consequence of along strike exposure of the reservoir rocks. The potential for deeper, subthrust, trapping geometries was recognized in the early 1970s however, exploration at the time was hindered by very poor quality seismic data and significant drilling difficulties. The 1980s exploration effort was characterized by continued poor quality seismic data and drilling difficulties combined with a geological perception that there wasmore » no effective reservoir and the majority of the structures post dated the major period of hydrocarbon generation and migration. The Cusiana discovery with a gross hydrocarbon column in excess of 1500{prime} reservoired within the Mirador (Eocene), Barco (Palaeocene) and Guadalupe (Upper Cretaceous) Formations in a large thrust anticline demonstrated the presence of a working hydrocarbon system. Subsequent exploration of the trend to the north has resulted in the discovery of four further giant oil and gas fields, Cupiagua (500 MMBBLs, 1-2 tcf) and the Florena/Pauto/Volcanera complex with estimated reserves of 1 billion barrels and 10 tcf. Key to this success has been the seismic imaging of the trapping geometries resulting from a significant improvement in the quality of the seismic data - a consequence of improvements in both acquisition and processing technology, combined with a recognition that pure quartz arenites retain reservoir quality at significant depths of burial-and that despite original depths of burial of greater than 18,000 ft, reservoir quality was not a major risk for further exploration success.« less

Organic matter and modeling redox reactions during river bank filtration in an alluvial aquifer of the Lot River, France.

PubMed

Kedziorek, Monika A M; Geoffriau, Stephane; Bourg, Alain C M

2008-04-15

A 3 year study of the infiltration of Lot River water into a well field located in an adjacent gravel and clay alluvial aquifer was conducted to assess the importance of organic matter regarding the redox processes which influence groundwater quality in a positive (denitrification) or negative (Mn dissolution) manner. Chloride was used to quantify the mixing of river water with groundwater. According to modeling with PHREEQC, the biodegradation of the infiltrated dissolved organic carbon (DOCi) is not sufficient to explain the observed consequences of the redox reactions (dissolved O2 depletion, denitrification, Mn dissolution). Another electron donor source must therefore be involved: we propose solid organic carbon (SOC) as a likely candidate, if made available for degradation by prior hydrolysis. Its contribution to redox reactions could be significant (30-80% of the total organic carbon consumed by redox reactions during river bank filtration). We show here also that even though the first few meters of infiltration are highly reactive, significant redox reactions can take place further in the aquifer, possibly affecting groundwater quality away from the river bank.

Review of Selected References and Data sets on Ambient Ground- and Surface-Water Quality in the Metedeconk River, Toms River, and Kettle Creek Basins, New Jersey, 1980-2001

USGS Publications Warehouse

Nicholson, Robert S.; Hunchak-Kariouk, Kathryn; Cauller, Stephen J.

2003-01-01

Surface water and ground water from unconfined aquifers are the primary sources of drinking water for much of the population, about 391,000, in the Metedeconk River, Toms River, and Kettle Creek watersheds in the New Jersey Coastal Plain. The quality of these sources of drinking water is a concern because they are vulnerable to contamination. Indications of the occurrence, distribution, and likely sources and transport mechanisms of certain contaminants were obtained from 48 selected reports and 2 selected data sets on water quality in or near the watersheds (1980-2001). These indications are described and briefly summarized in this report. The findings of studies on ground-water quality indicate that shallow ground water within the study area generally meets primary drinking-water standards, with notable exceptions. Volatile organic compounds, mercury, arsenic, radionuclides, nitrate, and coliform bacteria have been detected in shallow ground water in some areas at levels that exceed Federal and State drinking-water standards. For example, results of analyses of untreated samples collected from more than 13,000 private wells during 1983-99 indicated that concentrations of volatile organic compounds in samples from 7.3 percent of the wells exceeded at least 1 of 11 drinking-water standards, according to records maintained by the Ocean County Health Department. In cases of exceedances, however, water treatment, well replacement, and (or) retesting assured that applicable drinking-water standards were being met at the tap. Reported concentrations of the pesticide chlordane in some areas exceeded the drinking-water standard; few data are available on the occurrence of other pesticides. Studies of nearby areas, however, indicate that pesticide concentrations generally could be expected to be below drinking-water standards. The combination of low pH and low dissolved solids in many areas results in shallow ground water that is highly corrosive and, if untreated, able to leach trace elements and release asbestos fibers from plumbing materials. Reported concentrations of nitrate, volatile organic compounds, trace elements, and pesticides in samples from the monitored mainstem and tributary streams within the study area generally are below maximum contaminant levels for drinking water or below detection limits. Results of studies in other areas indicate that pesticide concentrations in surface water could be considerably higher during high flows soon after the application of pesticides to crops than during low flows. Fecal coliform bacteria counts in streams vary considerably. Concentrations or counts of these classes of surface-water-quality constituents likely are functions of the intensity and type of upstream development. Results of limited monitoring for radionuclide concentrations reported by the Brick Township Municipal Utilities Authority of the Metedeconk River indicate that radionuclide concentrations or activities do not exceed maximum contaminant levels for drinking water. As a consequence of organic matter in surface water, the formati ultraviolet absorbance in samples from the Metedeconk River and the Toms River exceeded the alternative compliance criteria for source water (2.0 milligrams per liter for total organic carbon and 0.02 absorbance units-liters per milligram-centimeter for specific ultraviolet absorbance) with respect to treatment requirements for preventing elevated concentrations of disinfection by-products in treated water. Water-quality and treatment issues associated with use of ground and surface water for potable supply in the study area are related to human activities and naturally occurring factors. Additional monitoring and analysis of ground and surface water would be needed to determine conclusively the occurrence and distribution of some contaminants and the relative importance of various potential contaminant sources, transport and attenuation mechanisms, and transport pathways.

Quantifying the combined effects of land use and climate changes on stream flow and nutrient loads: A modelling approach in the Odense Fjord catchment (Denmark).

PubMed

Molina-Navarro, Eugenio; Andersen, Hans E; Nielsen, Anders; Thodsen, Hans; Trolle, Dennis

2018-04-15

Water pollution and water scarcity are among the main environmental challenges faced by the European Union, and multiple stressors compromise the integrity of water resources and ecosystems. Particularly in lowland areas of northern Europe, high population density, flood protection and, especially, intensive agriculture, are important drivers of water quality degradation. In addition, future climate and land use changes may interact, with uncertain consequences for water resources. Modelling approaches have become essential to address water issues and to evaluate ecosystem management. In this work, three multi-stressor future storylines combining climatic and socio-economic changes, defined at European level, have been downscaled for the Odense Fjord catchment (Denmark), giving three scenarios: High-Tech agriculture (HT), Agriculture for Nature (AN) and Market-Driven agriculture (MD). The impacts of these scenarios on water discharge and inorganic and organic nutrient loads to the streams have been simulated using the Soil and Water Assessment Tool (SWAT). The results revealed that the scenario-specific climate inputs were most important when simulating hydrology, increasing river discharge in the HT and MD scenarios (which followed the high emission 8.5 representative concentration pathway, RCP), while remaining stable in the AN scenario (RCP 4.5). Moreover, discharge was the main driver of changes in organic nutrients and inorganic phosphorus loads that consequently increased in a high emission scenario. Nevertheless, both land use (via inputs of fertilizer) and climate changes affected the nitrate transport. Different levels of fertilization yielded a decrease in the nitrate load in AN and an increase in MD. In HT, however, nitrate losses remained stable because the fertilization decrease was counteracted by a flow increase. Thus, our results suggest that N loads will ultimately depend on future land use and management in an interaction with climate changes, and this knowledge is of utmost importance for the achievement of European environmental policy goals. Copyright © 2017 Elsevier B.V. All rights reserved.

Managing sewer solids for the reduction of foul flush effects--Forfar WTP.

PubMed

Fraser, A G; Sakrabani, R; Ashley, R M; Johnstone, F M

2002-01-01

In times of high sewer flow, conditions can exist which enable previously deposited material to be re-entrained back into the body of the flow column. Pulses of this highly polluted flow have been recorded in many instances at the recently constructed wastewater treatment plant (WTP) in Forfar, Scotland. Investigations have been undertaken to characterise the incoming flows and to suggest remedial measures to manage the quality fluctuations. Initial visits to the works and incoming pipes indicated a high degree of sediment deposition in the two inlet pipes. Analyses were carried out and consequently, changes to the hydraulic regime were made. Measurements of sediment level, sediment quality, wall slime and bulk water quality were monitored in the period following the remedial works to observe any improvements. Dramatic alterations in each of the determinands measured were recorded. Analyses were then undertaken to determine long term sediment behaviour and to assess the future usefulness of existing upstream sediment traps. It was concluded that with proper maintenance of the traps, the new hydraulic regime is sufficient to prevent further significant build up of sediment deposits and reduce impacts on the WTP. Further investigations made by North of Scotland Water Authority highlighted trade inputs to the system which may also have contributed to the now managed foul flush problem.

Changes in waste stabilisation pond performance resulting from the retrofit of activated sludge treatment upstream: part I--water quality issues.

PubMed

Cromar, N J; Sweeney, D G; O'Brien, M J; Fallowfield, H J

2005-01-01

This paper describes changes in effluent quality occurring before and after an upgrade to the Bolivar Wastewater Treatment Plant in South Australia. Trickling filters (TF) were replaced with an activated sludge (AS) plant, prior to tertiary treatment using waste stabilisation ponds (WSPs). The water quality in the WSPs following the upgrade was significantly improved. Reductions in total and soluble BOD, COD, TKN, suspended solids and organic nitrogen were recorded and the predominant form of inorganic nitrogen changed from NH(4)-N to NO(2)/NO(3)-N. The reduction in ammonium and potentially toxic free ammonia removed a control upon the growth of zooplankton, which may have contributed to decreases in algal biomass in the final ponds and consequently lower dissolved oxygen. Additionally, changes in inorganic nitrogen speciation contributed to a slightly elevated pH which reduced numbers of faecal coliforms in WSPs. The AS pretreated influent recorded significantly lower inorganic molar N:P ratio (10-4:1) compared to those fed with TF effluent (17-13:1). Algae within the WSPs may now be nitrogen limited, a condition which may favour the growth of nitrogen-fixing cyanobacteria. The decrease in algal biomass and in dissolved oxygen levels may enhance sedimentary denitrification, further driving the system towards nitrogen limitation.

A High Throughput In Vivo Assay for Taste Quality and Palatability

PubMed Central

Palmer, R. Kyle; Long, Daniel; Brennan, Francis; Buber, Tulu; Bryant, Robert; Salemme, F. Raymond

2013-01-01

Taste quality and palatability are two of the most important properties measured in the evaluation of taste stimuli. Human panels can report both aspects, but are of limited experimental flexibility and throughput capacity. Relatively efficient animal models for taste evaluation have been developed, but each of them is designed to measure either taste quality or palatability as independent experimental endpoints. We present here a new apparatus and method for high throughput quantification of both taste quality and palatability using rats in an operant taste discrimination paradigm. Cohorts of four rats were trained in a modified operant chamber to sample taste stimuli by licking solutions from a 96-well plate that moved in a randomized pattern beneath the chamber floor. As a rat’s tongue entered the well it disrupted a laser beam projecting across the top of the 96-well plate, consequently producing two retractable levers that operated a pellet dispenser. The taste of sucrose was associated with food reinforcement by presses on a sucrose-designated lever, whereas the taste of water and other basic tastes were associated with the alternative lever. Each disruption of the laser was counted as a lick. Using this procedure, rats were trained to discriminate 100 mM sucrose from water, quinine, citric acid, and NaCl with 90-100% accuracy. Palatability was determined by the number of licks per trial and, due to intermediate rates of licking for water, was quantifiable along the entire spectrum of appetitiveness to aversiveness. All 96 samples were evaluated within 90 minute test sessions with no evidence of desensitization or fatigue. The technology is capable of generating multiple concentration–response functions within a single session, is suitable for in vivo primary screening of tastant libraries, and potentially can be used to evaluate stimuli for any taste system. PMID:23951319

Summary of Surface-Water Quality Data from the Illinois River Basin in Northeast Oklahoma, 1970-2007

USGS Publications Warehouse

Andrews, William J.; Becker, Mark F.; Smith, S. Jerrod; Tortorelli, Robert L.

2009-01-01

The quality of streams in the Illinois River Basin of northeastern Oklahoma is potentially threatened by increased quantities of wastes discharged from increasing human populations, grazing of about 160,000 cattle, and confined animal feeding operations raising about 20 million chickens. Increasing numbers of humans and livestock in the basin contribute nutrients and bacteria to surface water and groundwater, causing greater than the typical concentrations of those constituents for this region. Consequences of increasing contributions of these substances can include increased algal growth (eutrophication) in streams and lakes; impairment of habitat for native aquatic animals, including desirable game fish species; impairment of drinking-water quality by sediments, turbidity, taste-and-odor causing chemicals, toxic algal compounds, and bacteria; and reduction in the aesthetic quality of the streams. The U.S. Geological Survey, in cooperation with the Oklahoma Scenic Rivers Commission, prepared this report to summarize the surface-water-quality data collected by the U.S. Geological Survey at five long-term surface-water-quality monitoring sites. The data summarized include major ions, nutrients, sediment, and fecal-indicator bacteria from the Illinois River Basin in Oklahoma for 1970 through 2007. General water chemistry, concentrations of nitrogen and phosphorus compounds, chlorophyll-a (an indicator of algal biomass), fecal-indicator bacteria counts, and sediment concentrations were similar among the five long-term monitoring sites in the Illinois River Basin in northeast Oklahoma. Most water samples were phosphorus-limited, meaning that they contained a smaller proportion of phosphorus, relative to nitrogen, than typically occurs in algal tissues. Greater degrees of nitrogen limitation occurred at three of the five sites which were sampled back to the 1970s, probably due to use of detergents containing greater concentrations of phosphorus than in subsequent periods. Concentrations of nitrogen, phosphorus, and sediment, and counts of bacteria generally increased with streamflow at the five sites, probably due to runoff from the land surface and re-suspension of streambed sediments. Phosphorus concentrations typically exceeded the Oklahoma standard of 0.037 milligrams per liter for Scenic Rivers. Concentrations of chlorophyll-a in phytoplankton in water samples collected at the five sites were not well correlated with streamflow, nor to concentrations of the nutrients nitrogen and phosphorus, probably because much of the algae growing in these streams are periphyton attached to streambed cobbles and other debris, rather than phytoplankton in the water column. Sediment concentrations correlated with phosphorus concentrations in water samples collected at the sites, probably due to sorption of phosphorus to soil particles and streambed sediments and runoff of soils and animal wastes at the land surface and resuspension of streambed sediments and phosphorus during wet, high-flow periods. Fecal coliform bacteria counts at the five sites sometimes exceeded the Oklahoma Primary Body Contact Standard of 400 colonies per 100 milliliters when streamflows were greater than 1000 cubic feet per second. Ultimately, Lake Tenkiller, an important ecological and economic resource for the region, receives the compounds that runoff the land surface or seep to local streams from groundwater in the basin. Because of eutrophication from increased nutrient loading, Lake Tenkiller is listed for impairment by diminished dissolved oxygen concentrations, phosphorus, and chlorophyll-a by the State of Oklahoma in evaluation of surface-water quality required by section 303d of the Clean Water Act. Stored phosphorus in soils and streambed and lakebed sediments may continue to provide phosphorus to local streams and lakes for decades to come. Steps are being made to reduce local sources of phosphorus, including upgrades in capacity and effective

How Do Land-Use and Climate Change Affect Watershed ...

EPA Pesticide Factsheets

With the growing emphasis on biofuel crops and potential impacts of climate variability and change, there is a need to quantify their effects on hydrological processes for developing watershed management plans. Environmental consequences are currently estimated by utilizing computer models such as Soil and Water Assessment Tool (SWAT) to simulate watershed hydrology under projected climate and land-use scenarios to assess the effect on water quantity and/or quality. Such studies have largely been deterministic in nature, with the focus being on whether hydrologic variables such as runoff, sediment and/or nutrient loads increase or decrease from the baseline case under projected scenarios. However, studying how these changes would affect watershed health in a risk-based framework has not been attempted. In this study, impacts of several projected land-use and climate change scenarios on the health of the Wildcat Creek watershed in Indiana have been assessed through three risk indicators, namely reliability-resilience-vulnerability (R-R-V). Results indicate that cultivation of biofuel crops such as Miscanthus and switchgrass has the potential to improve risk indicator values with respect to sediment, total N and total P. Climate change scenarios that involved rising precipitation levels were found to negatively impact watershed health indicators. Trends of water quality constituents under risk-based watershed health assessment revealed nuances not readily a

Collaborative Potential between National Estuary Programs ...

EPA Pesticide Factsheets

Estuaries are among the most productive ecosystems in the world, providing unique habitat for freshwater and marine species as well as valuable social and economic benefits. The wealth of ecosystem goods and services from estuaries has led to growth and development of human communities in adjacent areas and an increase in human activities that can adversely affect water quality and critical habitat. Managing for sustainable estuaries requires a balance of environmental concerns with community social and economic values. This has created an opportunity to leverage Environmental Protection Agency (EPA) scientific knowledge and tools with National Estuary Program (NEP) planning and management expertise to address environmental challenges in important estuarine ecosystems. The non-regulatory National Estuary Program (NEP) was outlined in the Clean Water Act to provide stakeholders an opportunity to monitor and manage ‘nationally significant’ estuaries. Currently there are 28 estuaries in the NEP, broadly distributed across the Atlantic, Pacific and Gulf Coasts, and in Puerto Rico. The local NEP management conferences must address a variety of environmental issues, from water quality and natural resources to coastal and watershed development. While the underlying objectives of each NEP are quite similar, each has unique landscapes, land uses, waterbodies, habitats, biological resources, economies and social culture. Consequently, the effects and severity of anthr

Spatial heterogeneity of water quality in a highly degraded tropical freshwater ecosystem.

PubMed

Zambrano, Luis; Contreras, Victoria; Mazari-Hiriart, Marisa; Zarco-Arista, Alba E

2009-02-01

Awareness of environmental heterogeneity in ecosystems is critical for management and conservation. We used the Xochimilco freshwater system to describe the relationship between heterogeneity and human activities. This tropical aquatic ecosystem south of Mexico City is comprised of a network of interconnected canals and lakes that are influenced by agricultural and urban activities. Environmental heterogeneity was characterized by spatially extensive surveys within four regions of Xochimilco during rainy and dry seasons over 2 years. These surveys revealed a heterogeneous system that was shallow (1.1 m, SD=0.4 ), warm (17 degrees C, SD=2.9), well oxygenated (5.0 mg l(-1), SD=3), turbid (45.7 NTU SD = 26.96), and extremely nutrient-rich (NO(3)-N=15.9 mg l(-1), SD=13.7; NH(4)-N=2.88 mg l(-1), SD=4.24; and PO(4)-P=8.3 mg l(-1), SD=2.4). Most of the variables were not significantly different between years, but did differ between seasons, suggesting a dynamic system within a span of a year but with a high resilience over longer periods of time. Maps were produced using interpolations to describe distributions of all variables. There was no correlation between individual variables and land use. Consequently, we searched for relationships using all variables together by generating a combined water quality index. Significant differences in the index were apparent among the four regions. Index values also differed within individual region and individual water bodies (e.g., within canals), indicating that Xochimilco has high local heterogeneity. Using this index on a map helped to relate water quality to human activities and provides a simple and clear tool for managers and policymakers.

Spatial Heterogeneity of Water Quality in a Highly Degraded Tropical Freshwater Ecosystem

NASA Astrophysics Data System (ADS)

Zambrano, Luis; Contreras, Victoria; Mazari-Hiriart, Marisa; Zarco-Arista, Alba E.

2009-02-01

Awareness of environmental heterogeneity in ecosystems is critical for management and conservation. We used the Xochimilco freshwater system to describe the relationship between heterogeneity and human activities. This tropical aquatic ecosystem south of Mexico City is comprised of a network of interconnected canals and lakes that are influenced by agricultural and urban activities. Environmental heterogeneity was characterized by spatially extensive surveys within four regions of Xochimilco during rainy and dry seasons over 2 years. These surveys revealed a heterogeneous system that was shallow (1.1 m, SD = 0.4 ), warm (17°C, SD = 2.9), well oxygenated (5.0 mg l-1, SD = 3), turbid (45.7 NTU SD = 26.96), and extremely nutrient-rich (NO3-N = 15.9 mg l-1, SD=13.7; NH4-N = 2.88 mg l-1, SD = 4.24; and PO4-P = 8.3 mg l-1, SD = 2.4). Most of the variables were not significantly different between years, but did differ between seasons, suggesting a dynamic system within a span of a year but with a high resilience over longer periods of time. Maps were produced using interpolations to describe distributions of all variables. There was no correlation between individual variables and land use. Consequently, we searched for relationships using all variables together by generating a combined water quality index. Significant differences in the index were apparent among the four regions. Index values also differed within individual region and individual water bodies (e.g., within canals), indicating that Xochimilco has high local heterogeneity. Using this index on a map helped to relate water quality to human activities and provides a simple and clear tool for managers and policymakers.

Modeling riverine nitrate export from an East-Central Illinois watershed using SWAT.

PubMed

Hu, X; McIsaac, G F; David, M B; Louwers, C A L

2007-01-01

Reliable water quality models are needed to forecast the water quality consequences of different agricultural nutrient management scenarios. In this study, the Soil and Water Assessment Tool (SWAT), version 2000, was applied to simulate streamflow, riverine nitrate (NO(3)) export, crop yield, and watershed nitrogen (N) budgets in the upper Embarras River (UER) watershed in east-central Illinois, which has extensive maize-soybean cultivation, large N fertilizer input, and extensive tile drainage. During the calibration (1994-2002) and validation (1985-1993) periods, SWAT simulated monthly and annual stream flows with Nash-Sutcliffe coefficients (E) ranging from 0.67 to 0.94 and R(2) from 0.75 to 0.95. For monthly and annual NO(3) loads, E ranged from -0.16 to 0.45 and R(2) from 0.36 to 0.74. Annual maize and soybean yields were simulated with relative errors ranging from -10 to 6%. The model was then used to predict the changes in NO(3) output with N fertilizer application rates 10 to 50% lower than original application rates in UER. The calibrated SWAT predicted a 10 to 43% decrease in NO(3) export from UER and a 6 to 38% reduction in maize yield in response to the reduction in N fertilizer. The SWAT model markedly overestimated NO(3) export during major wet periods. Moreover, SWAT estimated soybean N fixation rates considerably greater than literature values, and some simulated changes in the N cycle in response to fertilizer reduction seemed to be unrealistic. Improving these aspects of SWAT could lead to more reliable predictions in the water quality outcomes of nutrient management practices in tile-drained watersheds.

Inter-event variability in urban stormwater runoff response associated with hydrologic connectivity

NASA Astrophysics Data System (ADS)

Hondula, K. L.

2015-12-01

Urbanization alters the magnitude and composition of hydrologic and biogeochemical fluxes from watersheds, with subsequent deleterious consequences for receiving waters. Projected changes in storm characteristics such as rainfall intensity and event size are predicted to amplify these impacts and render current regulations inadequate for protecting surface water quality. As stormwater management practices (BMPs) are increasingly being relied upon to reduce excess nutrient pollution in runoff from residential development, empirical investigation of their performance across a range of conditions is warranted. Despite substantial investment in urban and suburban BMPs, significant knowledge gaps exist in understanding how landscape structure and precipitation event characteristics influence the amount of stormwater runoff and associated nutrient loads from these complex catchments. Increasing infiltration of stormwater before it enters the sewer network (source control) is hypothesized to better mimic natural hydrologic and biogeochemical fluxes compared to more centralized BMPs at sewer outlets such as wet and dry ponds. Rainfall and runoff quality and quantity were monitored in four small (1-5 ha) residential catchments in Maryland to test the efficacy of infiltration-based stormwater management practices in comparison to end-of-pipe BMPs. Results indicated that reduced hydrologic connectivity associated with infiltration-based practices affected the relationship between the magnitude of rainfall events and water yield , but only for small precipitation events: compared to end-of-pipe BMPs, source control was associated with both lower runoff ratios and lower nutrient export per area for a given rainfall event size. We found variability in stormwater runoff responses (water yield, quality, and nutrient loads) was associated with precipitation event size, antecedent rainfall, and hydrologic connectivity as quantified by a modified directional connectivity index. Accounting for the interactive effects of landscape structure and precipitation event characteristics can reduce the uncertainty surrounding stormwater runoff responses in complex urban watersheds.

Prioritizing urban sustainability solutions: coordinated approaches must incorporate scale-dependent built environment induced effects

NASA Astrophysics Data System (ADS)

Georgescu, M.; Chow, W. T. L.; Wang, Z. H.; Brazel, A.; Trapido-Lurie, B.; Roth, M.; Benson-Lira, V.

2015-06-01

Because of a projected surge of several billion urban inhabitants by mid-century, a rising urgency exists to advance local and strategically deployed measures intended to ameliorate negative consequences on urban climate (e.g., heat stress, poor air quality, energy/water availability). Here we highlight the importance of incorporating scale-dependent built environment induced solutions within the broader umbrella of urban sustainability outcomes, thereby accounting for fundamental physical principles. Contemporary and future design of settlements demands cooperative participation between planners, architects, and relevant stakeholders, with the urban and global climate community, which recognizes the complexity of the physical systems involved and is ideally fit to quantitatively examine the viability of proposed solutions. Such participatory efforts can aid the development of locally sensible approaches by integrating across the socioeconomic and climatic continuum, therefore providing opportunities facilitating comprehensive solutions that maximize benefits and limit unintended consequences.

Integrated modelling for the evaluation of infiltration effects.

PubMed

Schulz, N; Baur, R; Krebs, P

2005-01-01

The objective of the present study is the estimation of the potential benefits of sewer pipe rehabilitation for the performance of the drainage system and the wastewater treatment plant (WWTP) as well as for the receiving water quality. The relation of sewer system status and the infiltration rate is assessed based on statistical analysis of 470 km of CCTV (Closed Circuit Television) inspected sewers of the city of Dresden. The potential reduction of infiltration rates and the consequent performance improvements of the urban wastewater system are simulated as a function of rehabilitation activities in the network. The integrated model is applied to an artificial system with input from a real sewer network. In this paper, the general design of the integrated model and its data requirements are presented. For an exemplary study, the consequences of the simulations are discussed with respect to the prioritisation of rehabilitation activities in the network.

Instream coliform gradients in the Holtemme, a small headwater stream in the Elbe River Basin, Northern Germany

NASA Astrophysics Data System (ADS)

Karthe, Daniel; Lin, Pei-Ying; Westphal, Katja

2017-09-01

The Holtemme is a small headwater stream in North Germany's Elbe River Basin. According to German and European legislation, hygienic monitoring is not mandatory for such water bodies which are neither drinking water sources nor categorized as bathing waters. Consequently, relatively little is known about the occurrence of-potentially pathogenic-bacteria and viruses in Germany's streams and rivers. The Holtemme was selected for a case study because it is relatively well monitored for both chemical water quality and aquatic ecology, but not for hygiene. Originating in the mountains of Harz Nature Park, the 47 km long Holtemme is characterized by a strong longitudinal gradient in chemical water quality, which is related to different land uses and the influx of treated wastewater from two urban areas (Wernigerode and Halberstadt). Waste water loads received by the Holtemme are comparatively high when compared to similarly small streams. In 2015, total coliform concentrations between more than 200 and 77,010 bacteria per 100 mL, and fecal coliform concentrations between 5 and 24,060 bacteria per 100 mL were observed in the Holtemme's main channel. The highest concentrations were typically found below the outlets of the two wastewater treatment plants. The treated wastewater contained total and fecal coliform concentrations of up to 200,500 and 83,100 per 100 mL, respectively; however, there were significant temporal variations. While the observed concentrations are unproblematic from a legal perspective (because no maximum permissible limits are defined for streams in Germany), they would exceed the tolerable limits for bathing waters in the EU, indicating moderate to critical pollution limits.

What surface water tells about groundwater in lowlands - and what it does not

NASA Astrophysics Data System (ADS)

Steidl, Jörg; Lischeid, Gunnar; Kalettka, Thomas; Dannowski, Ralf; Merz, Christoph

2017-04-01

Lowland regions often exhibit a high density streams, lakes, ponds and wetlands. This holds, e.g., for Northeast Europe. As a consequence of heterogeneous sedimentation during and after glaciation, and temporarily dead ice blocks left behind in the late stage of the last glaciation, the landscape is now spotted by small depressions that are often filled with water, called kettle holes. Tight coupling between groundwater and surface water with non-stationary gradients and flow directions is often considered rather complex and surely is a challenge for hydrological models. However, on the other hand, close links imply that the one system bears information about the other and vice versa. For example, for the 170 km2 Quillow catchment in Northeast Germany a detailed groundwater map was generated from airborne remote sensing data exclusively, that is, from laser scan data of water level elevation in streams and kettle holes. On average, about 12 points of support per km2 were used. Such a high density can hardly be achieved at that scale based on groundwater wells. The resulting map was checked for consistency and plausibility. The groundwater map allowed delineating the catchments of the single kettle holes in order to assess the impact of land use of water quality. These catchments differed substantially from those determined based on topography. In general, the former usually exhibited a clearly elongated shape of up to some km length, resembling more single groundwater flowpaths rather than exhibiting the typical shape of stream catchments. Analysis of water quality monitoring data revealed that kettle hole water reflected the concentration of earth and alkaline earth metals of the shallow groundwater. However, this did not hold for nutrients and redox sensitive solutes due to rapid biogeochemical turnover in the eutrophic to hypertrophic small lentic systems.

Diversity and community structure of cyanobacteria and other microbes in recycling irrigation reservoirs.

PubMed

Kong, Ping; Richardson, Patricia; Hong, Chuanxue

2017-01-01

Recycling irrigation reservoirs (RIRs) are emerging aquatic environments of global significance to crop production, water conservation and environmental sustainability. This study characterized the diversity and population structure of cyanobacteria and other detected microbes in water samples from eight RIRs and one adjacent runoff-free stream at three ornamental crop nurseries in eastern (VA1 and VA3) and central (VA2) Virginia after cloning and sequencing the 16S rRNA gene targeting cyanobacteria and chloroplast of eukaryotic phytoplankton. VA1 and VA2 utilize a multi-reservoir recycling irrigation system with runoff channeled to a sedimentation reservoir which then overflows into transition and retention reservoirs where water was pumped for irrigation. VA3 has a single sedimentation reservoir which was also used for irrigation. A total of 208 operational taxonomic units (OTU) were identified from clone libraries of the water samples. Among them, 53 OTUs (358 clones) were cyanobacteria comprising at least 12 genera dominated by Synechococcus species; 59 OTUs (387 clones) were eukaryotic phytoplankton including green algae and diatoms; and 96 were other bacteria (111 clones). Overall, cyanobacteria were dominant in sedimentation reservoirs, while eukaryotic phytoplankton and other bacteria were dominant in transition/retention reservoirs and the stream, respectively. These results are direct evidence demonstrating the negative impact of nutrient-rich horticultural runoff, if not contained, on natural water resources. They also help in understanding the dynamics of water quality in RIRs and have practical implications. Although both single- and multi-reservoir recycling irrigation systems reduce the environmental footprint of horticultural production, the former is expected to have more cyanobacterial blooming, and consequently water quality issues, than the latter. Thus, a multi-reservoir recycling irrigation system should be preferred where feasible.

Diversity and community structure of cyanobacteria and other microbes in recycling irrigation reservoirs

PubMed Central

Kong, Ping; Richardson, Patricia; Hong, Chuanxue

2017-01-01

Recycling irrigation reservoirs (RIRs) are emerging aquatic environments of global significance to crop production, water conservation and environmental sustainability. This study characterized the diversity and population structure of cyanobacteria and other detected microbes in water samples from eight RIRs and one adjacent runoff-free stream at three ornamental crop nurseries in eastern (VA1 and VA3) and central (VA2) Virginia after cloning and sequencing the 16S rRNA gene targeting cyanobacteria and chloroplast of eukaryotic phytoplankton. VA1 and VA2 utilize a multi-reservoir recycling irrigation system with runoff channeled to a sedimentation reservoir which then overflows into transition and retention reservoirs where water was pumped for irrigation. VA3 has a single sedimentation reservoir which was also used for irrigation. A total of 208 operational taxonomic units (OTU) were identified from clone libraries of the water samples. Among them, 53 OTUs (358 clones) were cyanobacteria comprising at least 12 genera dominated by Synechococcus species; 59 OTUs (387 clones) were eukaryotic phytoplankton including green algae and diatoms; and 96 were other bacteria (111 clones). Overall, cyanobacteria were dominant in sedimentation reservoirs, while eukaryotic phytoplankton and other bacteria were dominant in transition/retention reservoirs and the stream, respectively. These results are direct evidence demonstrating the negative impact of nutrient-rich horticultural runoff, if not contained, on natural water resources. They also help in understanding the dynamics of water quality in RIRs and have practical implications. Although both single- and multi-reservoir recycling irrigation systems reduce the environmental footprint of horticultural production, the former is expected to have more cyanobacterial blooming, and consequently water quality issues, than the latter. Thus, a multi-reservoir recycling irrigation system should be preferred where feasible. PMID:28301562

A new methodology to identify surface water bodies at risk by using pesticide monitoring data: The glyphosate case study in Lombardy Region (Italy).

PubMed

Di Guardo, Andrea; Finizio, Antonio

2018-01-01

In the last decades, several monitoring programs were established as an effect of EU Directives addressing the quality of water resources (drinking water, groundwater and surface water). Plant Protection Products (PPPs) are an obvious target of monitoring activities, since they are directly released into the environment. One of the challenges in managing the risk of pesticides at the territorial scale is identifying the locations in water bodies needing implementation of risk mitigation measures. In this, the national pesticides monitoring plans could be very helpful. However, monitoring of pesticides is a challenging task because of the high number of registered pesticides, cost of analyses, and the periodicity of sampling related to pesticide application and use. Extensive high-quality data-sets are consequently often missing. More in general, the information that can be obtained from monitoring studies are frequently undervalued by risk managers. In this study, we propose a new methodology providing indications about the need to implement mitigation measures in stretches of surface water bodies on a territory by combining historical series of monitoring data and GIS. The methodology is articulated in two distinct phases: a) acquisition of monitoring data and setting-up of informative layers of georeferenced data (phase 1) and b) statistical and expert analysis for the identification of areas where implementation of limitation or mitigation measures are suggested (phase 2). Our methodology identifies potentially vulnerable water bodies, considering temporal contamination trends and relative risk levels at selected monitoring stations. A case study is presented considering glyphosate monitoring data in Lombardy Region (Northern of Italy) for the 2008-2014 period. Copyright © 2017 Elsevier B.V. All rights reserved.

Advancing Land-Sea Conservation Planning: Integrating Modelling of Catchments, Land-Use Change, and River Plumes to Prioritise Catchment Management and Protection.

PubMed

Álvarez-Romero, Jorge G; Pressey, Robert L; Ban, Natalie C; Brodie, Jon

2015-01-01

Human-induced changes to river loads of nutrients and sediments pose a significant threat to marine ecosystems. Ongoing land-use change can further increase these loads, and amplify the impacts of land-based threats on vulnerable marine ecosystems. Consequently, there is a need to assess these threats and prioritise actions to mitigate their impacts. A key question regarding prioritisation is whether actions in catchments to maintain coastal-marine water quality can be spatially congruent with actions for other management objectives, such as conserving terrestrial biodiversity. In selected catchments draining into the Gulf of California, Mexico, we employed Land Change Modeller to assess the vulnerability of areas with native vegetation to conversion into crops, pasture, and urban areas. We then used SedNet, a catchment modelling tool, to map the sources and estimate pollutant loads delivered to the Gulf by these catchments. Following these analyses, we used modelled river plumes to identify marine areas likely influenced by land-based pollutants. Finally, we prioritised areas for catchment management based on objectives for conservation of terrestrial biodiversity and objectives for water quality that recognised links between pollutant sources and affected marine areas. Our objectives for coastal-marine water quality were to reduce sediment and nutrient discharges from anthropic areas, and minimise future increases in coastal sedimentation and eutrophication. Our objectives for protection of terrestrial biodiversity covered species of vertebrates. We used Marxan, a conservation planning tool, to prioritise interventions and explore spatial differences in priorities for both objectives. Notable differences in the distributions of land values for terrestrial biodiversity and coastal-marine water quality indicated the likely need for trade-offs between catchment management objectives. However, there were priority areas that contributed to both sets of objectives. Our study demonstrates a practical approach to integrating models of catchments, land-use change, and river plumes with conservation planning software to inform prioritisation of catchment management.

Advancing Land-Sea Conservation Planning: Integrating Modelling of Catchments, Land-Use Change, and River Plumes to Prioritise Catchment Management and Protection

PubMed Central

Álvarez-Romero, Jorge G.; Pressey, Robert L.; Ban, Natalie C.; Brodie, Jon

2015-01-01

Human-induced changes to river loads of nutrients and sediments pose a significant threat to marine ecosystems. Ongoing land-use change can further increase these loads, and amplify the impacts of land-based threats on vulnerable marine ecosystems. Consequently, there is a need to assess these threats and prioritise actions to mitigate their impacts. A key question regarding prioritisation is whether actions in catchments to maintain coastal-marine water quality can be spatially congruent with actions for other management objectives, such as conserving terrestrial biodiversity. In selected catchments draining into the Gulf of California, Mexico, we employed Land Change Modeller to assess the vulnerability of areas with native vegetation to conversion into crops, pasture, and urban areas. We then used SedNet, a catchment modelling tool, to map the sources and estimate pollutant loads delivered to the Gulf by these catchments. Following these analyses, we used modelled river plumes to identify marine areas likely influenced by land-based pollutants. Finally, we prioritised areas for catchment management based on objectives for conservation of terrestrial biodiversity and objectives for water quality that recognised links between pollutant sources and affected marine areas. Our objectives for coastal-marine water quality were to reduce sediment and nutrient discharges from anthropic areas, and minimise future increases in coastal sedimentation and eutrophication. Our objectives for protection of terrestrial biodiversity covered species of vertebrates. We used Marxan, a conservation planning tool, to prioritise interventions and explore spatial differences in priorities for both objectives. Notable differences in the distributions of land values for terrestrial biodiversity and coastal-marine water quality indicated the likely need for trade-offs between catchment management objectives. However, there were priority areas that contributed to both sets of objectives. Our study demonstrates a practical approach to integrating models of catchments, land-use change, and river plumes with conservation planning software to inform prioritisation of catchment management. PMID:26714166

Chapter 1: Hydrologic exchange flows and their ecological consequences in river corridors

USGS Publications Warehouse

Harvey, Judson

2016-01-01

The actively flowing waters of streams and rivers remain in close contact with surrounding off-channel and subsurface environments. These hydrologic linkages between relatively fast flowing channel waters, with more slowly flowing waters off-channel and in the subsurface, are collectively referred to as hydrologic exchange flows (HEFs). HEFs include surface exchange with a channel’s marginal areas and subsurface flow through the streambed (hyporheic flow), as well as storm-driven bank storage and overbank flows onto floodplains. HEFs are important, not only for storing water and attenuating flood peaks, but also for their role in influencing water conservation, water quality improvement, and related outcomes for ecological values and services of aquatic ecosystems. Biogeochemical opportunities for chemical transformations are increased by HEFs as a result of the prolonged contact between flowing waters and geochemically and microbially active surfaces of sediments and vegetation. Chemical processing is intensified and water quality is often improved by removal of excess nutrients, metals, and organic contaminants from flowing waters. HEFs also are important regulators of organic matter decomposition, nutrient recycling, and stream metabolism that helps establish a balanced and resilient aquatic food web. The shallow and protected storage zones associated with HEFs support nursery and feeding areas for aquatic organisms that sustain aquatic biological diversity. Understanding of these varied roles for HEFs has been driven by the related disciplines of stream ecology, fluvial geomorphology, surface-water hydraulics, and groundwater hydrology. A current research emphasis is on the role that HEFs play in altered flow regimes, including restoration to achieve diverse goals, such as expanding aquatic habitats and managing dissolved and suspended river loads to reduce over-fertilization of coastal waters and offset wetland loss. New integrative concepts and models are emerging (eg, hydrologic connectivity) that emphasize HEF functions in river corridors over a wide range of spatial and temporal scales.

Quality-Assurance Plan for Water-Quality Activities in the USGS Ohio Water Science Center

USGS Publications Warehouse

Francy, Donna S.; Shaffer, Kimberly H.

2008-01-01

In accordance with guidelines set forth by the Office of Water Quality in the Water Resources Discipline of the U.S. Geological Survey, a quality-assurance plan has been written for use by the Ohio Water Science Center in conducting water-quality activities. This quality-assurance plan documents the standards, policies, and procedures used by the Ohio Water Science Center for activities related to the collection, processing, storage, analysis, and publication of water-quality data. The policies and procedures documented in this quality-assurance plan for water-quality activities are meant to complement the Ohio Water Science Center quality-assurance plans for water-quality monitors, the microbiology laboratory, and surface-water and ground-water activities.

Warming increases nutrient mobilization and gaseous nitrogen removal from sediments across cascade reservoirs.

PubMed

Zhou, Xingpeng; Chen, Nengwang; Yan, Zhihao; Duan, Shuiwang

2016-12-01

Increases in water temperature, as a result of climate change, may influence biogeochemical cycles, sediment-water fluxes and consequently environmental sustainability. Effects of rising temperature on dynamics of nitrate, nitrite, ammonium, dissolved inorganic nitrogen (DIN), dissolved reactive phosphorus (DRP), dissolved organic carbon (DOC) and gaseous nitrogen (N 2 and N 2 O) were examined in a subtropical river (the Jiulong River, southeast China) by microcosm experiments. Slurry sediments and overlying water were collected from three continuous cascade reservoirs, and laboratory incubations were performed at four temperature gradients (5 °C, 15 °C, 25 °C and 35 °C). Results indicated: (1) warming considerably increased sediment ammonium, DIN and DOC fluxes to overlying water; (2) warming increased retention of nitrate, and to a lesser extent, nitrite, corresponding to increases in N 2 and N 2 O emission; (3) DRP was retained but released from Fe/Al-P enriched sediments at high temperature (35 °C) due to enhanced coupled transformation of carbon and nitrogen with oxygen deficiency. Using relationships between sediment fluxes and temperature, a projected 2.3°C-warming in future would increase ammonium flux from sediment by 7.0%-16.8%, while increasing nitrate flux into sediment by 8.9%-28.6%. Moreover, substrates (e.g., grain size, carbon availability) influenced nutrient delivery and cycling across cascade reservoirs. This study highlights that warming would increase bioreactive nutrient (i.e., ammonium and phosphate) mobilization with limited gaseous N removal from sediments, consequently deteriorating water quality and increasing eutrophication with future climate change. Copyright © 2016 Elsevier Ltd. All rights reserved.

Unintended consequences of management actions in salt pond restoration: cascading effects in trophic interactions

USGS Publications Warehouse

Takekawa, John Y.; Ackerman, Joshua T.; Brand, Arriana; Graham, Tanya R.; Eagles-Smith, Collin A.; Herzog, Mark; Topping, Brent R.; Shellenbarger, Gregory; Kuwabara, James S.; Mruz, Eric; Piotter, Sara L.; Athearn, Nicole D.

2015-01-01

Salt evaporation ponds have played an important role as habitat for migratory waterbirds across the world, however, efforts to restore and manage these habitats to maximize their conservation value has proven to be challenging. For example, salinity reduction has been a goal for restoring and managing former salt evaporation ponds to support waterbirds in the South Bay Salt Pond Restoration Project in San Francisco Bay, California, USA. Here, we describe a case study of unexpected consequences of a low-dissolved oxygen (DO) event on trophic interactions in a salt pond system following management actions to reduce salinity concentrations. We document the ramifications of an anoxic event in water quality including salinity, DO, and temperature, and in the response of the biota including prey fish biomass, numerical response by California Gulls (Larus californicus), and chick survival of Forster's Tern (Sterna forsteri). Management actions intended to protect receiving waters resulted in decreased DO concentrations that collapsed to zero for ≥ 4 consecutive days, resulting in an extensive fish kill. DO depletion likely resulted from an algal bloom that arose following transition of the pond system from high to low salinity as respiration and decomposition outpaced photosynthetic production. We measured a ≥ 6-fold increase in biomass of fish dropped on the levee by foraging avian predators compared with weeks prior to and following the low-DO event. California Gulls rapidly responded to the availability of aerobically-stressed and vulnerable fish and increased in abundance by two orders of magnitude. Mark-recapture analysis of 254 Forster's Tern chicks indicated that their survival declined substantially following the increase in gull abundance. Thus, management actions to reduce salinity concentrations resulted in cascading effects in trophic interactions that serves as a cautionary tale illustrating the importance of understanding the interaction of water quality and trophic structure when managing restoration of salt ponds.

Unintended Consequences of Management Actions in Salt Pond Restoration: Cascading Effects in Trophic Interactions

PubMed Central

Takekawa, John Y.; Ackerman, Joshua T.; Brand, L. Arriana; Graham, Tanya R.; Eagles-Smith, Collin A.; Herzog, Mark P.; Topping, Brent R.; Shellenbarger, Gregory G.; Kuwabara, James S.; Mruz, Eric; Piotter, Sara L.; Athearn, Nicole D.

2015-01-01

Salt evaporation ponds have played an important role as habitat for migratory waterbirds across the world, however, efforts to restore and manage these habitats to maximize their conservation value has proven to be challenging. For example, salinity reduction has been a goal for restoring and managing former salt evaporation ponds to support waterbirds in the South Bay Salt Pond Restoration Project in San Francisco Bay, California, USA. Here, we describe a case study of unexpected consequences of a low-dissolved oxygen (DO) event on trophic interactions in a salt pond system following management actions to reduce salinity concentrations. We document the ramifications of an anoxic event in water quality including salinity, DO, and temperature, and in the response of the biota including prey fish biomass, numerical response by California Gulls (Larus californicus), and chick survival of Forster's Tern (Sterna forsteri). Management actions intended to protect receiving waters resulted in decreased DO concentrations that collapsed to zero for ≥ 4 consecutive days, resulting in an extensive fish kill. DO depletion likely resulted from an algal bloom that arose following transition of the pond system from high to low salinity as respiration and decomposition outpaced photosynthetic production. We measured a ≥ 6-fold increase in biomass of fish dropped on the levee by foraging avian predators compared with weeks prior to and following the low-DO event. California Gulls rapidly responded to the availability of aerobically-stressed and vulnerable fish and increased in abundance by two orders of magnitude. Mark-recapture analysis of 254 Forster's Tern chicks indicated that their survival declined substantially following the increase in gull abundance. Thus, management actions to reduce salinity concentrations resulted in cascading effects in trophic interactions that serves as a cautionary tale illustrating the importance of understanding the interaction of water quality and trophic structure when managing restoration of salt ponds. PMID:26030415

SERS as an analytical tool in environmental science: The detection of sulfamethoxazole in the nanomolar range by applying a microfluidic cartridge setup.

PubMed

Patze, Sophie; Huebner, Uwe; Liebold, Falk; Weber, Karina; Cialla-May, Dana; Popp, Juergen

2017-01-01

Sulfamethoxazole (SMX) is a commonly applied antibiotic for treating urinary tract infections; however, allergic reactions and skin eczema are known side effects that are observed for all sulfonamides. Today, this molecule is present in drinking and surface water sources. The allowed concentration in tap water is 2·10 -7  mol L -1 . SMX could unintentionally be ingested by healthy people when drinking contaminated tap water, representing unnecessary drug intake. To assess the quality of tap water, fast, specific and sensitive detection methods are required, in which consequence measures for improving the purification of water might be initiated in the short term. Herein, the quantitative detection of SMX down to environmentally and physiologically relevant concentrations in the nanomolar range by employing surface-enhanced Raman spectroscopy (SERS) and a microfluidic cartridge system is presented. By applying surface-water samples as matrices, the detection of SMX down to 2.2·10 -9  mol L -1 is achieved, which illustrates the great potential of our proposed method in environmental science. Copyright © 2016 Elsevier B.V. All rights reserved.

Effects of modifying water environments on water supply and human health

NASA Astrophysics Data System (ADS)

Takizawa, S.; Nguyen, H. T.; Takeda, T.; Tran, N. T.

2008-12-01

Due to increasing population and per-capita water demand, demands for water are increasing in many parts of the world. Consequently, overuse of limited water resources leaves only small amounts of water in rivers and is bringing about rapid drawdown of groundwater tables. Water resources are affected by human activities such as excessive inputs of nutrients and other contaminants, agriculture and aquaculture expansions, and many development activities. The combined effects of modifying the water environments, both in terms of quantity and quality, on water supply and human health are presented in the paper with some examples from the Asian countries. In rural and sub-urban areas in Bangladesh and Vietnam, for example, the traditional way of obtaining surface water from ponds had been replaced by taking groundwaters to avert the microbial health risks that had arisen from contamination by human wastes. Such a change of water sources, however, has brought about human health impact caused by arsenic on a massive scale. In Thailand, the industrial development has driven the residents to get groundwater leaden with very high fluoride. Monitoring the urine fluoride levels reveal the risk of drinking fluoride-laden groundwaters. Rivers are also affected by extensive exploitation such as sand mining. As a result, turbidity changes abruptly after a heavy rainfall. In cities, due to shrinking water resources they have to take poor quality waters from contaminated sources. Algal blooms are seen in many reservoirs and lakes due to increasing levels of nutrients. Hence, it is likely that algal toxins may enter the water supply systems. Because most of the water treatment plants are not designed to remove those known and unknown contaminants, it is estimated that quite a large number of people are now under the threat of the public health "gtime bomb,"h which may one day bring about mass-scale health problems. In order to mitigate the negative impacts of modifying the water environments on human health, we have to develop tools to assess and predict such impacts. This paper presents methodologies to assess the current status of water resources degradation and resultant effects on human health are discussed based on some case studies.

Development of innovative computer software to facilitate the setup and computation of water quality index.

PubMed

Nabizadeh, Ramin; Valadi Amin, Maryam; Alimohammadi, Mahmood; Naddafi, Kazem; Mahvi, Amir Hossein; Yousefzadeh, Samira

2013-04-26

Developing a water quality index which is used to convert the water quality dataset into a single number is the most important task of most water quality monitoring programmes. As the water quality index setup is based on different local obstacles, it is not feasible to introduce a definite water quality index to reveal the water quality level. In this study, an innovative software application, the Iranian Water Quality Index Software (IWQIS), is presented in order to facilitate calculation of a water quality index based on dynamic weight factors, which will help users to compute the water quality index in cases where some parameters are missing from the datasets. A dataset containing 735 water samples of drinking water quality in different parts of the country was used to show the performance of this software using different criteria parameters. The software proved to be an efficient tool to facilitate the setup of water quality indices based on flexible use of variables and water quality databases.

Waste management to improve food safety and security for health advancement.

PubMed

Lin, Angela Yu-Chen; Huang, Susana Tzy-Ying; Wahlqvist, Mark L

2009-01-01

Economic growth inevitably influences the food chain. Growing demand with changes in lifestyle and health consciousness encourage use of packaged and pre-prepared foods. The needs of environmental protection from waste generated are largely overlooked, and a lack of knowledge about the impact on the environment and its health effects constitute food security/safety problems. Food production and waste generation directly affect resource (i.e., energy and water) consumption and often contaminate the environment. More pressure on food production has inculcated the use of pesticides, herbicides, antibiotics and chemical fertilizers which add to current global pollution. At least half of food grown is discarded before and after it reaches consumers. It is estimated that one third to half of landfill waste comes from the food sector. This landfill releases green house gases (GHG) as well as leachate which worsen soil and water quality and safety. Pharmaceutical and chemical contaminations from residential, industrial and agricultural sources make their way into nearby water and soil and can eventually affect our food systems. Phthalates, PFOA, BPA, commonly used in plastics and personal care products, are found in unacceptable concentrations in Taiwanese waters. They, too, contribute to food contamination and long-term health risk. Existing waste management strategies warrant more stringent norms for waste reduction at source. Awareness through education could reduce food waste and its consequences. This review encompasses impacts of food production systems on the environment, pollution which results from food waste, costs and economic advantages in food waste management, and health consequences of waste.

What's in Your Water? An Educator's Guide to Water Quality.

ERIC Educational Resources Information Center

Constabile, Kerry, Comp.; Craig, Heidi, Comp.; O'Laughlin, Laura, Comp.; Reiss, Anne Bei, Comp.; Spencer, Liz, Comp.

This guide provides basic information on the Clean Water Act, watersheds, and testing for water quality, and presents four science lesson plans on water quality. Activities include: (1) "Introduction to Water Quality"; (2) "Chemical Water Quality Testing"; (3) "Biological Water Quality Testing"; and (4) "What Can We Do?" (YDS)

Dental unit water lines decontamination with the aid of nanotechnology.

PubMed

Paramashivaiah, Rashmi; Prabhuji, M L V; Narayanan, Roopalakshmi

2016-01-01

This article reviews the issue of dental unit waterline (DUWL) contamination which affects all the clinical and hospital settings. The contaminating microorganisms commonly isolated from these settings and the most pathogenic among them have serious consequences. Over the years several measures are inculcated for decontamination of water, their advantages and shortcomings have been addressed. Options using nanotechnology which are available in the market are described briefly. A manual and electronic search was conducted. Google and PubMed were searched for relevant material from studies up to 2013. Medical Subject Headings words looked for were "Nanotechnology," "Water purification," and "Biofilms." Reviewed findings were summarized by topic, using the Preferred Reporting Items for Systematic Reviews and Meta-analyses statement for reporting. Seventy articles were shortlisted for articles pertaining to our topic of discussion. A systematic approach was followed by two independent reviewers and included eligibility criteria for study inclusion, data extraction, data synthesis, and drawing of conclusion. Dental waterline contamination is widespread in any type of dental setting having serious implications on clinicians and patients alike, especially elderly and immune-compromised. Hence, international bodies like center for disease and control and American Dental Association have come up with stringent measures for maintenance of water quality. A gamut of procedures has been tried to overcome this problem ranging from chlorinated products, water filters to the usage of distilled water. The use of nanoemulsions, nanofilters, nanomembranes, etc., and their applicability for routine usage is discussed. Biofilm formation in DUWLs is inevitable with the subsequent release of part of microbiota into the otherwise sterile dental settings. These consequences can be quite serious on clinicians and dental patients. Though conventional measures in water decontamination have been partly successful, the quest for more foolproof methods has led to the use of latest technology, i.e., nanotechnology. The most practical option has to be chosen based on the ease of their usage.

Quality-Assurance Plan for Water-Quality Activities of the U.S. Geological Survey Montana Water Science Center

USGS Publications Warehouse

Lambing, John H.

2006-01-01

In accordance with guidelines set forth by the Office of Water Quality in the Water Resources Discipline of the U.S. Geological Survey (USGS), a quality-assurance plan has been created for use by the USGS Montana Water Science Center in conducting water-quality activities. This quality-assurance plan documents the standards, policies, and procedures used by the USGS Montana Water Science Center for activities related to the collection, processing, storage, analysis, and publication of water-quality data. The policies and procedures presented in this quality-assurance plan for water-quality activities complement the quality-assurance plans for surface-water and ground-water activities and suspended-sediment analysis.

Effects of Artificial Supercooling Followed by Slow Freezing on the Microstructure and Qualities of Pork Loin

PubMed Central

2016-01-01

This study investigated the effects of artificial supercooling followed by still air freezing (SSF) on the qualities of pork loin. The qualities of pork frozen by SSF were compared with the fresh control (CT, stored at 4℃ for 24 h), slow freezing (SAF, still air freezing) and rapid freezing (EIF, ethanol immersion freezing) treatments. Compared with no supercooling phenomena of SAF and EIF, the extent of supercooling obtained by SSF treatment was 1.4℃. Despite that SSF was conducted with the same method with SAF, application of artificial supercooling accelerated the phase transition (traverse from -0.6℃ to -5℃) from 3.07 h (SAF) to 2.23 h (SSF). The observation of a microstructure indicated that the SSF prevented tissue damage caused by ice crystallization and maintained the structural integrity. The estimated quality parameters reflected that SSF exhibited superior meat quality compared with slow freezing (SAF). SSF showed better water-holding capacity (lower thawing loss, cooking loss and expressible moisture) and tenderness than SAF, and these quality parameters of SSF were not significantly different with ultra-fast freezing treatment (EIF). Consequently, the results demonstrated that the generation of supercooling followed by conventional freezing potentially had the advantage of minimizing the quality deterioration caused by the slow freezing of meat. PMID:27857541

Hydrology of Area 62, Northern Great Plains and Rocky Mountain Coal Provinces, New Mexico and Arizona

USGS Publications Warehouse

Roybal, F.E.; Wells, J.G.; Gold, R.L.; Flager, J.V.

1984-01-01

This report summarizes available hydrologic data for Area 62 and will aid leasing decisions, and the preparation and appraisal of environmental impact studies and mine-permit applications. Area 62 is located at the southern end of the Rocky Mountain Coal Province in parts of New Mexico and Arizona and includes approximately 9,500 square miles. Surface mining alters, at least temporarily, the environment; if the areas are unreclaimed, there can be long-term environmental consequences. The land-ownership pattern in Area 62 is complicated. The checkerboard pattern created by several types of ownership makes effective management of these lands difficult. The climate generally is semiarid with average annual precipitation ranging from 10 to 20 inches. Pinons, junipers, and grasslands cover most of the area, and much of it is used for grazing by livestock. Soils vary with landscape, differing from flood plains and hillslopes to mountain slopes. The major structural features of this area were largely developed during middle Tertiary time. The main structural features are the southern San Juan Basin and the Mogollon slope. Coal-bearing rocks are present in four Cretaceous rock units of the Mesaverde Group: the Gallup Sandstone, the Dileo Coal Member, and the Gibson Coal Member of the Crevasse Canyon Formation, and the Cleary Coal Member of the Menefee Formation. Area 62 is drained by Black Creek, the Puerco River, the Zuni River, Carrizo Wash-Largo Creek, and the Rio San Jose. Only at the headwaters of the Zuni River is the flow perennial. The streamflow-gaging station network consists of 25 stations operated for a variety of needs. Streamflow changes throughout the year with variation related directly to rainfall and snowmelt. Base flow in Area 62 is zero indicating no significant ground-water discharge. Mountainous areas contribute the highest mean annual runoff of 1.0 inch. Very few water-quality data are available for the surface-water stations. Of the nine surface-water stations that have water-quality data, only one has chemical analyses from more than 10 samples. Therefore, sufficient data to characterize the area in detail are not available. Suspended sediment data are available only for a few surface- water stations in the area. Erosion rates generally are less than 1 acre-foot per square mile per year. Greater erosion rates are found within the badland areas. Water levels are periodically measured at 21 selected wells in Area 62. These observation wells are located mostly along the Rio San Jose and northeast of Gallup, New Mexico. The recharge to ground-water aquifers generally coincide with areas of greater precipitation in the mountainous areas. Depth to water below land surface is generally less than 200 feet. Well yields of 100 gallons per minute are common in most of the area. Ground-water quality is variable both within each aquifer and between aquifers. Water quality generally is best near recharge areas. Historical and current data related to stream discharge, water quality, and suspended sediment are available from computer files in the U.S. Geological Survey's National Water Data Storage and Retrieval System (WATSTORE) and through the National Water Data Exchange (NAWDEX).

Upper Illinois River basin

USGS Publications Warehouse

Friedel, Michael J.

1998-01-01

During the past 25 years, industry and government made large financial investments that resulted in better water quality across the Nation; however, many water-quality concerns remain. Following a 1986 pilot project, the U.S. Geological Survey began implementation of the National Water-Quality Assessment (NAWQA) Program in 1991. This program differs from other national water-quality assessment studies in that the NAWQA integrates monitoring of surface- and ground-water quality with the study of aquatic ecosystems. The goals of the NAWQA Program are to (1) describe current water-quality conditions for a large part of the Nation's freshwater streams and aquifers (water-bearing sediments and rocks), (2) describe how water quality is changing over time, and (3) improve our understanding of the primary natural and human factors affecting water quality.The Upper Illinois River Basin National Water- Quality Assessment (NAWQA) study will increase the scientific understanding of surface- and ground-water quality and the factors that affect water quality in the basin. The study also will provide information needed by water-resource managers to implement effective water-quality management actions and evaluate long-term changes in water quality.

Irrigation efficiency and water-policy implications for river basin resilience

NASA Astrophysics Data System (ADS)

Scott, C. A.; Vicuña, S.; Blanco-Gutiérrez, I.; Meza, F.; Varela-Ortega, C.

2014-04-01

Rising demand for food, fiber, and biofuels drives expanding irrigation withdrawals from surface water and groundwater. Irrigation efficiency and water savings have become watchwords in response to climate-induced hydrological variability, increasing freshwater demand for other uses including ecosystem water needs, and low economic productivity of irrigation compared to most other uses. We identify three classes of unintended consequences, presented here as paradoxes. Ever-tighter cycling of water has been shown to increase resource use, an example of the efficiency paradox. In the absence of effective policy to constrain irrigated-area expansion using "saved water", efficiency can aggravate scarcity, deteriorate resource quality, and impair river basin resilience through loss of flexibility and redundancy. Water scarcity and salinity effects in the lower reaches of basins (symptomatic of the scale paradox) may partly be offset over the short-term through groundwater pumping or increasing surface water storage capacity. However, declining ecological flows and increasing salinity have important implications for riparian and estuarine ecosystems and for non-irrigation human uses of water including urban supply and energy generation, examples of the sectoral paradox. This paper briefly considers three regional contexts with broadly similar climatic and water-resource conditions - central Chile, southwestern US, and south-central Spain - where irrigation efficiency directly influences basin resilience. The comparison leads to more generic insights on water policy in relation to irrigation efficiency and emerging or overdue needs for environmental protection.

Improving indoor air quality through botanical air filtration in energy efficient residences

NASA Astrophysics Data System (ADS)

Newkirk, Daniel W.

According to the U.S. EPA, the average American spends 90% of their time indoors where pollutants are two to five times more prevalent than outside. The consequences of these pollutants are estimated to cost the U.S. 125 billion dollars in lost health and productivity. Background literature suggests botanical air filtration may be able to solve this problem by leveraging the natural ability of plants to purify indoor air. By improving indoor air quality, energy consumption can also be reduced by bringing in less outside air to dilute contaminants within the space. A botanical air filter, called the Biowall, was designed and grown aeroponically in a sealed environmental chamber. Precise measurements of air temperature, air humidity, air quality and energy consumption were made under various lighting levels, plant species and watering strategies to optimize its performance. It was found to reduce indoor air pollutants 60 percent and has the potential to reduce heating and cooling energy consumption by 20 to 30 percent.

Global water dynamics: issues for the 21st century.

PubMed

Simonovic, Slobodan P

2002-01-01

The WorldWater system dynamics model has been developed for modeling the global world water balance and capturing the dynamic character of the main variables affecting water availability and use in the future. Despite not being a novel approach, system dynamics offers a new way of addressing complex systems. WorldWater simulations are clearly demonstrating the strong feedback relation between water availability and different aspects of world development. Results of numerous simulations are contradictory to the assumption made by many global modelers that water is not an issue on the global scale. Two major observations can be made from early simulations: (a) the use of clean water for dilution and transport of wastewater, if not dealt with in other ways, imposes a major stress on the global world water balance; and (b) water use by different sectors is demonstrating quite different dynamics than predicted by classical forecasting tools and other water-models. Inherent linkages between water quantity and quality sectors with food, industry, persistent pollution, technology, and non-renewable resources sectors of the model create shoot and collapse behavior in water use dynamics. This paper discusses a number of different water-related scenarios and their implications on the global water balance. In particular, two extreme scenarios (business as usual - named "Chaos", and unlimited desalination - named "Ocean") are presented in the paper. Based on the conclusions derived from these two extreme cases a set of more moderate and realistic scenarios (named "Conservation") is proposed and their consequences on the global water balance are evaluated.

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.

Fate and transport of pesticides in the ground water systems of southwest Georgia, 1993-2005

USGS Publications Warehouse

Dalton, M.S.; Frick, E.A.

2008-01-01

Modern agricultural practices in the United States have resulted in nearly unrivaled efficiency and productivity. Unfortunately, there is also the potential for release of these compounds to the environment and consequent adverse affects on wildlife and human populations. Since 1993, the National Water-Quality Assessment (NAWQA) program of the U.S. Geological Survey has evaluated water quality in agricultural areas to address these concerns. The objective of this study is to evaluate trends in pesticide concentrations from 1993-2005 in the surficial and Upper Floridan aquifers of southwest Georgia using pesticide and pesticide degradate data collected for the NAWQA program. There were six compounds - five herbicides and one degradate - that were detected in more than 20% of samples: atrazine, deethylatrazine (DEA), metolachlor, alachlor, floumeturon, and tebuthiuron. Of the 128 wells sampled during the study, only eight wells had pesticide concentrations that either increased (7) or decreased (1) on a decadal time scale. Most of the significant trends were increasing concentrations of pesticides in older water; median pesticide concentrations did not differ between the surficial and Upper Floridan aquifers from 1993 and 2005. Deethylatrazine, in the Upper Floridan aquifer, was the only compound that had a significant change (increase) in concentration during the study. The limited number of wells with increases in pesticide concentrations suggest that ground-water sources of these compounds are not increasing in concentration over the time scale represented in this study. Copyright ?? 2008 by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America. All rights reserved.

Drinking water treatment response following a Colorado wildfire.

PubMed

Hohner, Amanda K; Cawley, Kaelin; Oropeza, Jill; Summers, R Scott; Rosario-Ortiz, Fernando L

2016-11-15

Wildfires can greatly alter the vegetation, soils, and hydrologic processes of watersheds serving as drinking water supplies, which may negatively influence source water quality and treatment. To address wildfire impacts on treatment, a drinking water intake below a burned watershed and an upstream, unburned reference site were monitored following the High Park wildfire (2012) in the Cache la Poudre watershed of northern Colorado, USA. Turbidity, nutrients, dissolved organic matter (DOM) character, coagulation treatability, and disinfection byproduct formation were evaluated and compared to pre-fire data. Post-fire paired spatial differences between the treatment plant intake and reference site for turbidity, nitrogen, and phosphorus increased by an order of magnitude compared to pre-fire differences. Fluorescence index (FI) values were significantly higher at the intake compared to the reference site (Δ = 0.04), and higher than pre-fire years, suggesting the wildfire altered the DOM character of the river. Total trihalomethane (TTHM) and haloacetonitrile (HAN4) formation at the intake were 10.1 μg L -1 and 0.91 μg L -1 higher than the reference site. Post-fire water was amenable to conventional treatment at a 10 mg L -1 higher average alum dose than reference samples. The intake was also monitored following rainstorms. Post-rainstorm samples showed the maximum observed FI values (1.52), HAN4 (3.4 μg mg C -1 ) and chloropicrin formation yields (3.6 μg mg C -1 ), whereas TTHM and haloacetic acid yields were not elevated. Several post-rainstorm samples presented treatment challenges, and even at high alum doses (65 mg L -1 ), showed minimal dissolved organic carbon removal (<10%). The degraded water quality of the post-rainstorm samples is likely attributed to the combined effects of runoff from precipitation and greater erosion following wildfire. Wildfire impacts cannot be separated from rainfall effects due to the lack of post-rainstorm samples from the reference site. Results suggest for this study region, wildfire may have consequences for influent water quality, coagulant dosing, and DBP speciation. Copyright © 2016 Elsevier Ltd. All rights reserved.

Water quality assessment with hierarchical cluster analysis based on Mahalanobis distance.

PubMed

Du, Xiangjun; Shao, Fengjing; Wu, Shunyao; Zhang, Hanlin; Xu, Si

2017-07-01

Water quality assessment is crucial for assessment of marine eutrophication, prediction of harmful algal blooms, and environment protection. Previous studies have developed many numeric modeling methods and data driven approaches for water quality assessment. The cluster analysis, an approach widely used for grouping data, has also been employed. However, there are complex correlations between water quality variables, which play important roles in water quality assessment but have always been overlooked. In this paper, we analyze correlations between water quality variables and propose an alternative method for water quality assessment with hierarchical cluster analysis based on Mahalanobis distance. Further, we cluster water quality data collected form coastal water of Bohai Sea and North Yellow Sea of China, and apply clustering results to evaluate its water quality. To evaluate the validity, we also cluster the water quality data with cluster analysis based on Euclidean distance, which are widely adopted by previous studies. The results show that our method is more suitable for water quality assessment with many correlated water quality variables. To our knowledge, it is the first attempt to apply Mahalanobis distance for coastal water quality assessment.

Development of innovative computer software to facilitate the setup and computation of water quality index

PubMed Central

2013-01-01

Background Developing a water quality index which is used to convert the water quality dataset into a single number is the most important task of most water quality monitoring programmes. As the water quality index setup is based on different local obstacles, it is not feasible to introduce a definite water quality index to reveal the water quality level. Findings In this study, an innovative software application, the Iranian Water Quality Index Software (IWQIS), is presented in order to facilitate calculation of a water quality index based on dynamic weight factors, which will help users to compute the water quality index in cases where some parameters are missing from the datasets. Conclusion A dataset containing 735 water samples of drinking water quality in different parts of the country was used to show the performance of this software using different criteria parameters. The software proved to be an efficient tool to facilitate the setup of water quality indices based on flexible use of variables and water quality databases. PMID:24499556

The quality of rivers: From pristine stage to global pollution

NASA Astrophysics Data System (ADS)

Meybeck, Michel; Helmer, Richard

1989-12-01

River water quality is highly variable by nature due to environmental conditions such as basin lithology, vegetation and climate. In small watersheds spatial variations extend over orders of magnitude for most major elements and nutrients, while this variability is an order of magnitude lower for major basins. A standard river water for use as reference is therefore not applicable. As a consequence natural waters can possibly be unfit for various human uses, even including drinking. The Water Quality (WQ) concept has greatly evolved since the beginning of the century in accordance with expanding water uses and analytical developments. Even in well developed countries the dissolved heavy metal measurements in rivers are not very reliable while dissolved organic micro-pollutants are even rarely analysed routinely. Major WQ problems have been identified according to river basin size, including organic pollution, salinity, total suspended solids, heavy metals, eutrophication, nitrate, organic micro-pollutants, acidification. They generally occurred in this order over a period of about 100 years in the industrialized countries. Historical records of WQ are rare but can be established indirectly through studies of lake sediments. When proper control action is taken at an early stage, numerous examples of WQ recovery have been found in rivers for most of the common pollution problems. Future WQ problems will mostly derive from mine tailings and toxic waste disposal in both developed and developing countries, industrial accidents and organic micropollutants which emerge faster than our analytical capacities. The newly industrializing countries will face all the above-mentioned problems within a very short time period without having the means to cope with them one at a time. River studies point out the global alteration of the biogeochemical cycles of many major elements and nutrients (S, Na, K, N, P). For heavy metals such as lead, present estimates of global river loads emphasize the role of interim storage on land, thus delaying downstream pollution problems.

Preferential flow in municipal solid waste and implications for long-term leachate quality: valuation of laboratory-scale experiments.

PubMed

Rosqvist, N H; Dollar, L H; Fourie, A B

2005-08-01

In this paper, we study and quantify pollutant concentrations after long-term leaching at relatively low flow rates and residual concentrations after heavy flushing of a 0.14 m3 municipal solid waste sample. Moreover, water flow and solute transport through preferential flow paths are studied by model interpretation of experimental break-through curves (BTCs), generated by tracer tests. In the study it was found that high concentrations of chloride remain after several pore volumes of water have percolated through the waste sample. The residual concentration was found to be considerably higher than can be predicted by degradation models. For model interpretations of the experimental BTCs, two probabilistic model approaches were applied, the transfer function model and the Lagrangian transport formulation. The experimental BTCs indicated the presence of preferential flow through the waste mass and the model interpretation of the BTCs suggested that between 19 and 41% of the total water content participated in the transport of solute through preferential flow paths. In the study, the occurrence of preferential flow was found to be dependent on the flow rate in the sense that a high flow rate enhances the preferential flow. However, to fully quantify the possible dependence between flow rate and preferential flow, experiments on a broader range of experimental conditions are suggested. The chloride washout curve obtained over the 4-year study period shows that as a consequence of the water flow in favoured flow paths, bypassing other parts of the solid waste body, the leachate quality may reflect only the flow paths and their surroundings. The results in this study thus show that in order to improve long-term prediction of the leachate quality and quantity the magnitude of the preferential water flow through a landfill must be taken into account.

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.

Increasing Efficiency of Water Use in Agriculture through Management of Soil Water Repellency to Optimize Soil and Water Productivity

NASA Astrophysics Data System (ADS)

Moore, Demie; Kostka, Stan; McMillan, Mica; Gadd, Nick

2010-05-01

Water's ability to infiltrate and disperse in soils, and soil's ability to receive, transport, retain, filter and release water are important factors in the efficient use of water in agriculture. Deteriorating soil conditions, including development of soil water repellency, negatively impact hydrological processes and, consequently, the efficiency of rainfall and irrigation. Soil water repellency is increasingly being identified in diverse soils and cropping systems. Recently research has been conducted on the use of novel soil surfactants (co-formulations of alkyl polyglycoside and block copolymer surfactants) to avoid or overcome soil water repellency and enhance water distribution in soils. Results indicate that this is an effective and affordable approach to maintaining or restoring soil and water productivity in irrigated cropping systems. Results from studies conducted in Australia and the United States to determine how this technology modifies soil hydrological behavior and crop yields will be presented. A range of soils and various crops, including potatoes, corn, apples and grapes, were included. Several rates were compared to controls for effect on soil moisture levels, soil water distribution, and crop yield. An economic analysis was also conducted in some trials. Treatments improved rootzone water status, significantly increased crop yield and quality, and in some cases allowed significant reductions in water requirements. Where assessed, a positive economic return was generated. This technology holds promise as a strategy for increasing efficiency of water use in agriculture.

The evolution of hydrological and water quality conditions on Techirghiol Lake

NASA Astrophysics Data System (ADS)

Maftei, Carmen; Buta, Constantin; Tofan, Lucica

2015-04-01

Changes in climate and environment conditions alter the hydraulic and chemical properties of lakes. With a surface from 1300ha, the Techirghiol Lake, situated on the littoral of the Black Sea at 15km from Constanta town, is considered the greatest hypersaline lake of Romania very well known (from 1891) especially for the curative qualities of its water and mud. Physical and geographical conditions associated with an arid climate regime - where the annual precipitation is less than 400mm and the average temperatures exceed (lead evaporative potential to 700-1000mm), cause a strong concentration of mineral salts that give the lake an excessive salinity. In conditions of excessive salinity forms a therapeutic mud as a result of bacterial decomposition of aquatic organisms that have done there, especially crustaceans Arthemia and algae that live in water. This mud, highly hydrated, rich in minerals, has therapeutic properties, for this reason in Techirghiol has developed a strong health resort. Fresh water is a threat to the therapeutic lake properties. In hydrological year 1961-1962, the overland flow value to the lake was approximately 0.4 million m3, and from 1972-1973 the value reached 6 million cubic meters per year a great contribution was from the irrigation water. One of the consequences is the increasing of the lake level and the second is the decreasing of salinity. For this reason a hydraulic work system has been built to separate the saline water of the lake and the freshwater. The aim of this paper is to investigate the hydrologic and chemical responses of the Techirghiol Lake to the changes in climate and environment conditions.

Does wastewater from olive mills induce toxicity and water repellency in soil?

NASA Astrophysics Data System (ADS)

Peikert, B.; Bandow, N.; Schaumann, G. E.

2012-04-01

Olive oil mill wastewater is the effluent generated by the olive oil extraction process. It is the main waste product of this industry mainly being produced in the Mediterranean Basin. Because proper treatment options are rare it is often disposed into the environment, e.g. fields or wadies. Due to its high concentration of fatty acids and phytotoxic phenolic compounds and its high chemical and biological oxygen demand, olive oil mill wastewater becomes a serious environmental problem. In this screening study we investigated long-term effects of olive oil mill wastewater application on soil properties in several locations in the West Bank and Israel. We determined wettability via water drop penetration time and the contact angle as well as general soil properties including pH, EC, carbon content, and we conducted thermogravimetrical analyses in order to characterize the impact of the waste water on the quality of soil organic matter. Our results show that application of olive oil mill wastewater has various effects. We determined contact angles between 110 and 120° and water drop penetration times up to 1367 s indicating significant reduction in wettability. Furthermore, soil carbon and nitrogen content and water extractable organic matter increased as well as electric conductivity, which could be pointed out as a fertilizing effect. In contrast soil pH was significantly reduced. Conducting thermal analyses we observed an increase in the labile and refractory carbon fraction. Probably first one is responsible for induced water repellency. As a consequence the reduced wettability negatively affects soil quality. It would therefore be promising to minimize the hydrophobizing impacts without losing fertilizing effects of the olive oil mill wastewater.

Persistence and extirpation in invaded landscapes: patch characteristics and connectivity determine effects of non-native predatory fish on native salamanders

USGS Publications Warehouse

Pilliod, David S.; Arkle, Robert S.; Maxell, Bryce A.

2012-01-01

Studies have demonstrated negative effects of non-native, predatory fishes on native amphibians, yet it is still unclear why some amphibian populations persist, while others are extirpated, following fish invasion. We examined this question by developing habitat-based occupancy models for the long-toed salamander (Ambystoma macrodactylum) and nonnative fish using survey data from 1,749 water bodies across 470 catchments in the Northern Rocky Mountains, USA. We first modeled the habitat associations of salamanders at 468 fishless water bodies in 154 catchments where non-native fish were historically, and are currently, absent from the entire catchment. Wethen applied this habitat model to the complete data set to predict the probability of salamander occupancy in each water body, removing any effect of fish presence. Finally, we compared field-observed occurrences of salamanders and fish to modeled probability of salamander occupancy. Suitability models indicated that fish and salamanders had similar habitat preferences, possibly resulting in extirpations of salamander populations from entire catchments where suitable habitats were limiting. Salamanders coexisted with non-native fish in some catchments by using marginal quality, isolated (no inlet or outlet) habitats that remained fishless. They rarely coexisted with fish within individual water bodies and only where habitat quality was highest. Connectivity of water bodies via streams resulted in increased probability of fish invasion and consequently reduced probability of salamander occupancy.These results could be used to identify and prioritize catchments and water bodies where control measures would be most effective at restoring amphibian populations. Our approach could be useful as a framework for improved investigations into questions of persistence and extirpation of native species when non-native species have already become established.

Macro-Invertebrate Decline in Surface Water Polluted with Imidacloprid

PubMed Central

Van Dijk, Tessa C.; Van Staalduinen, Marja A.; Van der Sluijs, Jeroen P.

2013-01-01

Imidacloprid is one of the most widely used insecticides in the world. Its concentration in surface water exceeds the water quality norms in many parts of the Netherlands. Several studies have demonstrated harmful effects of this neonicotinoid to a wide range of non-target species. Therefore we expected that surface water pollution with imidacloprid would negatively impact aquatic ecosystems. Availability of extensive monitoring data on the abundance of aquatic macro-invertebrate species, and on imidacloprid concentrations in surface water in the Netherlands enabled us to test this hypothesis. Our regression analysis showed a significant negative relationship (P<0.001) between macro-invertebrate abundance and imidacloprid concentration for all species pooled. A significant negative relationship was also found for the orders Amphipoda, Basommatophora, Diptera, Ephemeroptera and Isopoda, and for several species separately. The order Odonata had a negative relationship very close to the significance threshold of 0.05 (P = 0.051). However, in accordance with previous research, a positive relationship was found for the order Actinedida. We used the monitoring field data to test whether the existing three water quality norms for imidacloprid in the Netherlands are protective in real conditions. Our data show that macrofauna abundance drops sharply between 13 and 67 ng l−1. For aquatic ecosystem protection, two of the norms are not protective at all while the strictest norm of 13 ng l−1 (MTR) seems somewhat protective. In addition to the existing experimental evidence on the negative effects of imidacloprid on invertebrate life, our study, based on data from large-scale field monitoring during multiple years, shows that serious concern about the far-reaching consequences of the abundant use of imidacloprid for aquatic ecosystems is justified. PMID:23650513

Simulated effects of proposed Arkansas Valley Conduit on hydrodynamics and water quality for projected demands through 2070, Pueblo Reservoir, southeastern Colorado

USGS Publications Warehouse

Ortiz, Roderick F.

2013-01-01

The purpose of the Arkansas Valley Conduit (AVC) is to deliver water for municipal and industrial use within the boundaries of the Southeastern Colorado Water Conservancy District. Water supplied through the AVC would serve two needs: (1) to supplement or replace existing poor-quality water to communities downstream from Pueblo Reservoir; and (2) to meet a portion of the AVC participants’ projected water demands through 2070. The Bureau of Reclamation (Reclamation) initiated an Environmental Impact Statement (EIS) to address the potential environmental consequences associated with constructing and operating the proposed AVC, entering into a conveyance contract for the Pueblo Dam north-south outlet works interconnect (Interconnect), and entering into a long-term excess capacity master contract (Master Contract). Operational changes, as a result of implementation of proposed EIS alternatives, could change the hydrodynamics and water-quality conditions in Pueblo Reservoir. An interagency agreement was initiated between Reclamation and the U.S. Geological Survey to accurately simulate hydrodynamics and water quality in Pueblo Reservoir for projected demands associated with four of the seven proposed EIS alternatives. The four alternatives submitted to the USGS for scenario simulation included various combinations (action or no action) of the proposed Arkansas Valley Conduit, Master Contract, and Interconnect options. The four alternatives were the No Action, Comanche South, Joint Use Pipeline North, and Master Contract Only. Additionally, scenario simulations were done that represented existing conditions (Existing Conditions scenario) in Pueblo Reservoir. Water-surface elevations, water temperature, dissolved oxygen, dissolved solids, dissolved ammonia, dissolved nitrate, total phosphorus, total iron, and algal biomass (measured as chlorophyll-a) were simulated. Each of the scenarios was simulated for three contiguous water years representing a wet, average, and dry annual hydrologic cycle. Each selected simulation scenario also was evaluated for differences in direct/indirect effects and cumulative effects on a particular scenario. Analysis of the results for the direct/indirect- and cumulative-effects analyses indicated that, in general, the results were similar for most of the scenarios and comparisons in this report focused on results from the direct/indirect-effects analyses. Scenario simulations that represented existing conditions in Pueblo Reservoir were compared to the No Action scenario to assess changes in water quality from current demands (2006) to projected demands in 2070. Overall, comparisons of the results between the Existing Conditions and the No Action scenarios for water-surface elevations, water temperature, and dissolved oxygen, dissolved solids, dissolved ammonia, dissolved nitrate, total phosphorus, and total iron concentrations indicated that the annual median values generally were similar for all three simulated years. Additionally, algal groups and chlorophyll-a concentrations (algal biomass) were similar for the Existing Conditions and the No Action scenarios at site 7B in the epilimnion for the simulated period (Water Year 2000 through 2002). The No Action scenario also was compared individually to the Comanche South, Joint Use Pipeline North, and Master Contract Only scenarios. These comparisons were made to describe changes in the annual median, 85th percentile, or 15th percentile concentration between the No Action scenario and each of the other three simulation scenarios. Simulated water-surface elevations, water temperature, dissolved oxygen, dissolved solids, dissolved ammonia, dissolved nitrate, total phosphorus, total iron, algal groups, and chlorophyll-a concentrations in Pueblo Reservoir generally were similar between the No Action scenario and each of the other three simulation scenarios.

Water insecurity in Canadian Indigenous communities: some inconvenient truths.

PubMed

Sarkar, Atanu; Hanrahan, Maura; Hudson, Amy

2015-01-01

Canada has the second highest per capita water consumption in the world. However, little is known about complex socio-economic and cultural dynamics of water insecurities in Indigenous communities and the multiple health consequences. Most studies have concentrated on a simplified interpretation of accessibility, availability and quality issues, including some common water-borne infections as the only health outcomes. Thus, several government initiatives on potable water supply, particularly for remotely located communities, have failed to sustain and promote a healthy lifestyle. The objective was to explore the water insecurity, coping strategies and associated health risks in a small and isolated sub-Arctic Indigenous (Inuit) community in Canada. The study was based on a community-based survey (2013) in one of the most remote Inuit communities of Labrador. In-depth, open-ended key informant (KI) interviews (community leader (1), woman (1), nurse (1), teacher (1), and elder (1)) and focus group discussions (FGDs) were conducted with community leaders (5), community members (25), women (5), and high school students (8). Convenience sampling was followed in selection of the subjects for FGDs and approached some KIs. All the water sources (five in April and seven in October) were visited and tested for their physical, chemical and microbiological parameters. The FGDs and KI interviews were audio recorded and transcribed. In the analysis, the data (qualitative and quantitative) were broadly categorized into (a) water sources, access and quality, (b) coping, (c) health risks and (d) challenges to run a public water system. The community did not have any piped water supply. Their regular sources of water consisted of several unmonitored local streams, brooks, and ponds. The public water system was not affordable to the majority of community members who solely depended on government aid. Animal fecal contamination (in natural sources such as streams, brooks, and ponds) and the presence of disinfection by-products (in the public water system) were the major quality issues. Gastro-intestinal infections were the most common disease in the community. Per capita water consumption was less than one-third of the Canadian national average (274 L/day/person), severely compromising personal hygiene and water intake. High-sugar-content beverages were the most common alternative to lack of accessible and affordable potable water, particularly for children. Mental stress due to water insecurity and chronic back and shoulder injuries due to carrying heavy water buckets every day were the commonly encountered adverse health outcomes. Water insecurity has put the community at risk of multiple serious adverse health outcomes. The scenario is not unique in Canada. There are many remote Indigenous communities facing similar kinds of water insecurity.

Irrigation efficiency and water-policy implications for river-basin resilience

NASA Astrophysics Data System (ADS)

Scott, C. A.; Vicuña, S.; Blanco-Gutiérrez, I.; Meza, F.; Varela-Ortega, C.

2013-07-01

Rising demand for food, fiber, and biofuels drives expanding irrigation withdrawals from surface- and groundwater. Irrigation efficiency and water savings have become watchwords in response to climate-induced hydrological variability, increasing freshwater demand for other uses including ecosystem water needs, and low economic productivity of irrigation compared to most other uses. We identify three classes of unintended consequences, presented here as paradoxes. Ever-tighter cycling of water has been shown to increase resource use, an example of the efficiency paradox. In the absence of effective policy to constrain irrigated-area expansion using "saved water", efficiency can aggravate scarcity, deteriorate resource quality, and impair river-basin resilience through loss of flexibility and redundancy. Water scarcity and salinity effects in the lower reaches of basins (symptomatic of the scale paradox) may partly be offset over the short-term through groundwater pumping or increasing surface water storage capacity. However, declining ecological flows and increasing salinity have important implications for riparian and estuarine ecosystems and for non-irrigation human uses of water including urban supply and energy generation, examples of the sectoral paradox. This paper briefly examines policy frameworks in three regional contexts with broadly similar climatic and water-resource conditions - central Chile, southwestern US, and south-central Spain - where irrigation efficiency directly influences basin resilience. The comparison leads to more generic insights on water policy in relation to irrigation efficiency and emerging or overdue needs for environmental protection.

78 FR 20252 - Water Quality Standards; Withdrawal of Certain Federal Water Quality Criteria Applicable to...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-04

... aquatic life water quality criteria applicable to waters of New Jersey, Puerto Rico, and California's San Francisco Bay. In 1992, EPA promulgated the National Toxics Rule or NTR to establish numeric water quality... Water Quality Standards; Withdrawal of Certain Federal Water Quality Criteria Applicable to California...

Effects of climate events driven hydrodynamics on dissolved oxygen in a subtropical deep reservoir in Taiwan.

PubMed

Fan, Cheng-Wei; Kao, Shuh-Ji

2008-04-15

The seasonal concentrations of dissolved oxygen in a subtropical deep reservoir were studied over a period of one year. The study site was the Feitsui Reservoir in Taiwan. It is a dam-constructed reservoir with a surface area of 10.24 km(2) and a mean depth of 39.6 m, with a maximum depth of 113.5 m near the dam. It was found that certain weather and climate events, such as typhoons in summer and autumn, as well as cold fronts in winter, can deliver oxygen-rich water, and consequently have strong impacts on the dissolved oxygen level. The typhoon turbidity currents and winter density currents played important roles in supplying oxygen to the middle and bottom water, respectively. The whole process can be understood by the hydrodynamics driven by weather and climate events. This work provides the primary results of dissolved oxygen in a subtropical deep reservoir, and the knowledge is useful in understanding water quality in subtropical regions.

Cold fronts and reservoir limnology: an integrated approach towards the ecological dynamics of freshwater ecosystems.

PubMed

Tundisi, J G; Matsumura-Tundisi, T; Pereira, K C; Luzia, A P; Passerini, M D; Chiba, W A C; Morais, M A; Sebastien, N Y

2010-10-01

In this paper the authors discuss the effects of cold fronts on the dynamics of freshwater ecosystems of southeast South America. Cold fronts originating from the Antarctic show a monthly frequency that promotes turbulence and vertical mixing in reservoirs with a consequence to homogenize nutrient distribution, dissolved oxygen and temperature. Weak thermoclines and the athelomixis process immediately before, during and after the passage of cold fronts interfere with phytoplankton succession in reservoirs. Cyanobacteria blooms in eutrophic reservoirs are frequently connected with periods of stratification and stability of the water column. Cold fronts in the Amazon and Pantanal lakes may produce fish killings during the process of "friagem" associated mixing events. Further studies will try to implement a model to predict the impact of cold fronts and prepare management procedures in order to cope with cyanobacteria blooms during warm and stable water column periods. Changes in water quality of reservoirs are expected during circulation periods caused by cold fronts.

Influence of Network Model Detail on Estimated Health Effects of Drinking Water Contamination Events

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

Davis, Michael J.; Janke, Robert

Network model detail can influence the accuracy of results from analyses of water distribution systems. Some previous work has shown the limitations of skeletonized network models when considering water quality and hydraulic effects. Loss of model detail is potentially less important for aggregated effects such as the systemwide health effects associated with a contamination event, but has received limited attention. The influence of model detail on such effects is examined here by comparing results obtained for contamination events using three large network models and several skeletonized versions of the models. Loss of model detail decreases the accuracy of estimated aggregatedmore » adverse effects related to contamination events. It has the potential to have a large negative influence on the results of consequence assessments and the design of contamination warning systems. But, the adverse influence on analysis results can be minimized by restricting attention to high percentile effects (i.e., 95th percentile or higher).« less

Influence of Network Model Detail on Estimated Health Effects of Drinking Water Contamination Events

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

Davis, Michael J.; Janke, Robert

Network model detail can influence the accuracy of results from analyses of water distribution systems. Previous work has shown the limitations of skeletonized network models when considering water quality and hydraulic effects. Loss of model detail is potentially less important for aggregated effects such as the systemwide health effects associated with a contamination event, but has received limited attention. The influence of model detail on such effects is examined here by comparing results obtained for contamination events using three large network models and several skeletonized versions of the models. Loss of model detail decreases the accuracy of estimated aggregated adversemore » effects related to contamination events. It has the potential to have a large negative influence on the results of consequence assessments and the design of contamination warning systems. However, the adverse influence on analysis results can be minimized by restricting attention to high percentile effects (i.e., 95th percentile or higher).« less

Influence of Network Model Detail on Estimated Health Effects of Drinking Water Contamination Events

DOE PAGES

Davis, Michael J.; Janke, Robert

2015-01-01

Network model detail can influence the accuracy of results from analyses of water distribution systems. Some previous work has shown the limitations of skeletonized network models when considering water quality and hydraulic effects. Loss of model detail is potentially less important for aggregated effects such as the systemwide health effects associated with a contamination event, but has received limited attention. The influence of model detail on such effects is examined here by comparing results obtained for contamination events using three large network models and several skeletonized versions of the models. Loss of model detail decreases the accuracy of estimated aggregatedmore » adverse effects related to contamination events. It has the potential to have a large negative influence on the results of consequence assessments and the design of contamination warning systems. But, the adverse influence on analysis results can be minimized by restricting attention to high percentile effects (i.e., 95th percentile or higher).« less

Observations of transport of bacterial-like microspheres through beach sand

NASA Astrophysics Data System (ADS)

Gast, Rebecca J.; Elgar, Steve; Raubenheimer, Britt

2015-04-01

Often, there is an order of magnitude more fecal indicator bacteria (enterococci) in beach sand than in nearby water. Consequently, sand is considered a reservoir for these bacteria, potentially contributing to poor water quality, and raising questions regarding the human health risks associated with sand exposure. An integral aspect of the distribution and persistence of sand-associated enterococci is the transport of bacteria introduced into the beach environment. Here, plastic microspheres are used as a proxy to examine the wave-induced movement of bacterial-like particles through sand on an ocean beach. Laboratory tests suggest microspheres and bacteria move similarly through sand columns, and have qualitatively similar short-term adsorption-to-sand behavior. Microspheres buried ~0.05 m below the sand surface on an ocean beach moved rapidly [O(10-3) m/s] away from their initial location, both vertically into the ground water below the sand and horizontally seaward within the sediment matrix in response to waves running up the beach face and percolating through the sand.

Comparison of precipitable water vapor measurements obtained by microwave radiometry and radiosondes at the Southern Great ...

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

Lesht, B.M.; Liljegren, J.C.

1996-12-31

Comparisons between the precipitable water vapor (PWV) estimated by passive microwave radiometers (MWRs) and that obtained by integrating the vertical profile of water vapor density measured by radiosondes (BBSS) have generally shown good agreement. These comparisons, however, have usually been done over rather short time periods and consequently within limited ranges of total PWV and with limited numbers of radiosondes. We have been making regular comparisons between MWR and BBSS estimates of PWV at the Southern Great Plains Cloud and Radiation Testbed (SGP/CART) site since late 1992 as part of an ongoing quality measurement experiment (QME). This suite of comparisonsmore » spans three annual cycles and a relatively wide range of total PWV amounts. Our findings show that although for the most part the agreement is excellent, differences between the two measurements occur. These differences may be related to the MWR retrieval of PWV and to calibration variations between radiosonde batches.« less

Atmospheric influence on the distribution of organic pollutants in the Guadalquivir River estuary, SW Spain.

PubMed

Fernández-Gómez, Cristal; López-López, José Antonio; Matamoros, Victor; Díez, Sergi; García-Vargas, Manuel; Moreno, Carlos

2013-04-01

In the lower Guadalquivir river basin, a system stressed by a wide variety of anthropogenic activities, eight pesticides (four triazines, two chloroacetanilide herbicides, one organochlorine, and one organophosphorus insecticide); and four emerging pollutants (two personal care products, one organophosphorous flame retardant, and one xanthine alkaloid) were analyzed in river water during a 2-year monitoring program, and after rain episodes. Samples were extracted using the solid phase extraction (SPE) technique prior to determination of compounds using gas chromatograph coupled to a mass spectrometer detector. Except for caffeine, recoveries were mostly above 80 %, while limits of detection and quantification were in the low nanograms per liter level (except for dimethoate). Terbuthylazine, simazine (triazine herbicides), and dimethoate (organophosphorus insecticide), present in agrochemicals, were predominant in the river water, although concentrations were below the quality standards established by the EU Water-Framework-Directive. A general trend to increase concentration was observed after rain events, in particular for pesticides, possibly as a consequence of surface runoff.

Quality-assurance plan for water-quality activities in the U.S. Geological Survey Washington Water Science Center

USGS Publications Warehouse

Conn, Kathleen E.; Huffman, Raegan L.; Barton, Cynthia

2017-05-08

In accordance with guidelines set forth by the Office of Water Quality in the Water Mission Area of the U.S. Geological Survey, a quality-assurance plan has been created for use by the Washington Water Science Center (WAWSC) in conducting water-quality activities. This qualityassurance plan documents the standards, policies, and procedures used by the WAWSC for activities related to the collection, processing, storage, analysis, and publication of water-quality data. The policies and procedures documented in this quality-assurance plan for water-quality activities complement the quality-assurance plans for surface-water and groundwater activities at the WAWSC.

Research on the Relationship between Water Diversion and Water Quality of Xuanwu Lake, China.

PubMed

Song, Weiwei; Xu, Qing; Fu, Xingqian; Zhang, Peng; Pang, Yong; Song, Dahao

2018-06-14

Water diversion is often used to improve water quality to reach the standard of China in the short term. However, this large amount of water diversion can not only improve the water quality, but also lead to a decline in the water quality (total phosphorus, total nitrogen) of Xuanwu Lake. Through theoretical analysis, the relationship between water quality and water diversion is established. We also found that the multiplication of the pollutant degradation coefficient ( K ) and the water residence time ( T ) is a constant ( N ), K⋅T=N. The water quality changed better at first, with the increase of inflow discharge, and then became worse, and the optimal water quality inflow discharge is 180,000 m³/day. By constructing two-dimensional hydrodynamic and water quality models, the optimal diversion water plan is calculated. Through model calculations, it can be seen that reducing the inflow discharge makes the water residence time longer (15.3 days changed to 23.8 days). Thereby, increasing the degradation of pollutants, and thus improving water quality. Compared with other wind directions, the southwest wind makes the water quality of Xuanwu Lake the most uniform. The concentration of water quality first became smaller and then became larger, as the wind speed increased, and eventually became constant. Implementing these results for water quality improvement in small and medium lakes will significantly reduce the cost of water diversion.

Spatio-Temporal Trends and Identification of Correlated Variables with Water Quality for Drinking-Water Reservoirs

PubMed Central

Gu, Qing; Wang, Ke; Li, Jiadan; Ma, Ligang; Deng, Jinsong; Zheng, Kefeng; Zhang, Xiaobin; Sheng, Li

2015-01-01

It is widely accepted that characterizing the spatio-temporal trends of water quality parameters and identifying correlated variables with water quality are indispensable for the management and protection of water resources. In this study, cluster analysis was used to classify 56 typical drinking water reservoirs in Zhejiang Province into three groups representing different water quality levels, using data of four water quality parameters for the period 2006–2010. Then, the spatio-temporal trends in water quality were analyzed, assisted by geographic information systems (GIS) technology and statistical analysis. The results indicated that the water quality showed a trend of degradation from southwest to northeast, and the overall water quality level was exacerbated during the study period. Correlation analysis was used to evaluate the relationships between water quality parameters and ten independent variables grouped into four categories (land use, socio-economic factors, geographical features, and reservoir attributes). According to the correlation coefficients, land use and socio-economic indicators were identified as the most significant factors related to reservoir water quality. The results offer insights into the spatio-temporal variations of water quality parameters and factors impacting the water quality of drinking water reservoirs in Zhejiang Province, and they could assist managers in making effective strategies to better protect water resources. PMID:26492263

Spatio-Temporal Trends and Identification of Correlated Variables with Water Quality for Drinking-Water Reservoirs.

PubMed

Gu, Qing; Wang, Ke; Li, Jiadan; Ma, Ligang; Deng, Jinsong; Zheng, Kefeng; Zhang, Xiaobin; Sheng, Li

2015-10-20

It is widely accepted that characterizing the spatio-temporal trends of water quality parameters and identifying correlated variables with water quality are indispensable for the management and protection of water resources. In this study, cluster analysis was used to classify 56 typical drinking water reservoirs in Zhejiang Province into three groups representing different water quality levels, using data of four water quality parameters for the period 2006-2010. Then, the spatio-temporal trends in water quality were analyzed, assisted by geographic information systems (GIS) technology and statistical analysis. The results indicated that the water quality showed a trend of degradation from southwest to northeast, and the overall water quality level was exacerbated during the study period. Correlation analysis was used to evaluate the relationships between water quality parameters and ten independent variables grouped into four categories (land use, socio-economic factors, geographical features, and reservoir attributes). According to the correlation coefficients, land use and socio-economic indicators were identified as the most significant factors related to reservoir water quality. The results offer insights into the spatio-temporal variations of water quality parameters and factors impacting the water quality of drinking water reservoirs in Zhejiang Province, and they could assist managers in making effective strategies to better protect water resources.

Chemical quality of surface water in the Allegheny River basin, Pennsylvania and New York

USGS Publications Warehouse

McCarren, Edward F.

1967-01-01

The Allegheny River is the principal source of water to many industries and to communities in the upper Ohio River Valley. The river and its many tributaries pass through 19 counties in northwestern and western Pennsylvania. The population in these counties exceeds 3 million. A major user of the Allegheny River is the city of Pittsburgh, which has a population greater than The Allegheny River is as basic to the economy of the upper Ohio River Valley in western Pennsylvania as are the rich deposits of bituminous coal, gas, and oil that underlie the drainage basin. During the past 5 years many streams that flow into the Allegheny have been low flowing because of droughts affecting much of the eastern United States. Consequently, the concentration of solutes in some streams has been unusually high because of wastes from coal mines and oil wells. These and other water-quality problems in the Allegheny River drainage basin are affecting the economic future of some areas in western Pennsylvania. Because of environmental factors such as climate, geology, and land and water uses, surface-water quality varies considerably throughout the river basin. The natural quality of headwater streams, for example, is affected by saltwater wastes from petroleum production. One of the streams most affected is Kinzua Creek, which had 2,900 parts per million chloride in a sample taken at Westline on September 2, 1959. However, after such streams as the Conewango, Brokenstraw, Tionesta, Oil, and French Creeks merge with the Allegheny River, the dissolved-solids and chloride concentrations are reduced by dilution. Central segments of the main river receive water from the Clarion River, Redbank, Mahoning, and Crooked Creeks after they have crossed the coal fields of west-central Pennsylvania. At times, therefore, these streams carry coal-mine wastes that are acidic. The Kiskiminetas River, which crosses these coal fields, discharged sulfuric acid into the Allegheny at a rate of 299 tons a day during the 1962 water year (October 1, 1961, to September 30, 1962). Mine water affects the quality of the Allegheny River most noticeably in its lower part where large withdrawals are made by the Pittsburgh Water Company at Aspinwall and the Wilkinsburg-Penn Joint Water Authority at Nadine. At these places raw river water is chemically .treated in modern treatment plants to control such objectionable characteristics as acidity and excessive concentrations of iron and manganese. Dissolved-solids content in the river varies along its entire length. In its upper reaches the water of the Allegheny River is a sodium chloride type, and at low flow, the sodium chloride is more than half the dissolved solids. In its lower reaches the water is a calcium sulfate .type, and at low flow the calcium sulfate is more than half the dissolved solids. In middle segments of the river from Franklin to Kittanning, water is more dilute and of a mixed type. Many small and several larger streams in the upper basin--such as the Conewango, Brokenstraw, Kinzua, Tionesta, and French Creeks--support large populations of game-fish. Even in segments of the Clarion River, Mahoning, and Redbank Creeks, which are at times affected by coal-mine wastes, fish are present. Although different species withstand varying amounts of contaminants in water, the continued presence of the fish indicates that the water is relatively pure and suitable for recreation and many other uses.

Hydrological change: reaping prosperity and pain in Australia

NASA Astrophysics Data System (ADS)

Dunin, F. X.; Smith, C. J.; Denmead, O. T.

2007-01-01

The adage: “There is no such thing as a free lunch”, is relevant to land-use hydrology in Australia. Changes in land use to achieve greater productivity of food and fibre may have an adverse effect on the water balance and hence on the natural resource capital of a catchment. An altered regime of catchment outflow accompanies those land-use changes which, together with land degradation, impairs available water resources in quantity and quality and threatens enterprise sustainability, notwithstanding the initial improvement in productivity. Central to any hydrological change is an altered pattern of seasonal and annual water use by vegetation that has become modified in function with an amended transpiration fraction of daily evapotranspiration. In Australia, since measurement of evapotranspiration became feasible, the hydrological consequences of changes in land use have been determined, allowing the benefits in terms of plant productivity achieved through enhanced water use efficiency to be weighed against changed catchment outflows, diminished in either quantity or quality. Four case studies are presented as examples of ecological and hydrological changes: two deal with the upland forest environment and two with arable lowlands. In an upland eucalypt forest, following wildfire with subsequent regeneration from natural seedling establishment, substantial reduction in water yield occurred throughout a 50-year period of succession in the even-aged stand. In comparison, the effect of converting eucalypt forest to pine plantations was less detrimental to the yield of water from the catchments, with substantial growth increases over 30 years. In the lowlands, agricultural productivity, both as annual pasture and as crop, far exceeds that of natural perennial grassland and woodland. This increase in productivity comes not so much from any change to the yield of total water outflow but at the expense of water quality, compromised with increased material transport in suspension and solution resulting from accelerated erosion in association with outbreaks of soil salinity and acidity. The present study is aimed at optimising management to give plant production outcomes that ensure environmental protection through resource conservation. In the uplands, harvesting of water is the dominant consideration so that conservative management with limited plant productivity is sought. In the lowlands, the objective is to devise novel ecosystems with profitable plant production that exercises due control on outflow in maintaining the chemical and physical integrity of the edaphic environment.

Monitoring and Assessment of Youshui River Water Quality in Youyang

NASA Astrophysics Data System (ADS)

Wang, Xue-qin; Wen, Juan; Chen, Ping-hua; Liu, Na-na

2018-02-01

By monitoring the water quality of Youshui River from January 2016 to December 2016, according to the indicator grading and the assessment standard of water quality, the formulas for 3 types water quality indexes are established. These 3 types water quality indexes, the single indicator index Ai, single moment index Ak and the comprehensive water quality index A, were used to quantitatively evaluate the quality of single indicator, the water quality and the change of water quality with time. The results show that, both total phosphorus and fecal coliform indicators exceeded the standard, while the other 16 indicators measured up to the standard. The water quality index of Youshui River is 0.93 and the grade of water quality comprehensive assessment is level 2, which indicated that the water quality of Youshui River is good, and there is room for further improvement. To this end, several protection measures for Youshui River environmental management and pollution treatment are proposed.

Water quality assessment of Australian ports using water quality evaluation indices

PubMed Central

Jahan, Sayka

2017-01-01

Australian ports serve diverse and extensive activities, such as shipping, tourism and fisheries, which may all impact the quality of port water. In this work water quality monitoring at different ports using a range of water quality evaluation indices was applied to assess the port water quality. Seawater samples at 30 stations in the year 2016–2017 from six ports in NSW, Australia, namely Port Jackson, Botany, Kembla, Newcastle, Yamba and Eden, were investigated to determine the physicochemical and biological variables that affect the port water quality. The large datasets obtained were designed to determine the Water Quality Index, Heavy metal Evaluation Index, Contamination Index and newly developed Environmental Water Quality Index. The study revealed medium water quality index and high and medium heavy metal evaluation index at three of the study ports and high contamination index in almost all study ports. Low level dissolved oxygen and higher level of total dissolved solids, turbidity, fecal coliforms, copper, iron, lead, zinc, manganese, cadmium and cobalt are mainly responsible for the poor water qualities of the port areas. Good water quality at the background samples indicated that various port activities are the likely cause for poor water quality inside the port area. PMID:29244876

Hydrological considerations in providing data for water agreements

NASA Astrophysics Data System (ADS)

Shamir, U.

2011-12-01

Conflicts over water are as old as human history. Still, analysis of past and present water conflicts, cooperation and agreements clearly indicate a preponderance of cooperation over conflict. How can hydrologists contribute to maximizing the probability that this will be the outcome when interests of adjacent political entities over water move towards conflict? Hydrology is among the most important data bases for crafting a water agreement across a political boundary (others include: political, social, and economic) and are often the most elusive and controversial. We deal here with cases of water scarcity, although flood protection issues are no less interesting and challenging. For hydrologists, some of the important points in this regard are: - Agreed and "stable" hydrological data base: hydrologists know that data bases are always a "moving target" that keeps changing with new and better information, improved understanding of the hydrological components and the use of models, as well as due to the influence of changing internal and external drivers (land use and land cover, modified precipitation fields, climate change). On the other hand, it is not possible to manage an agreement that requires continuous change of the hydrological information. To do so would cause endless discussions between the parties, causing the agreement to become unstable. The tendency is therefore to "freeze" the hydrological information in the agreement and introduce a mechanism for periodic update. - Variability and uncertainty: while the basic hydrology is to be kept "stable", the agreement must recognize variability and uncertainty. Various mechanisms can be used for this, depending on the specific circumstances of the case, including: the range of variability and the degree of uncertainty and the consequences of excursions systematic from nominal values and the effects of random variability. - Water quality is an important parameter that determines usability for various purposes, and requires treatment when source quality does not match consumer requirements. - Complexity/difficulty and associated cost of extraction/production to make the "potential" source water into "usable" water. - Look jointly for new sources and benefits (expand the "cake"): agreements should look beyond the issues and water sources that are under imminent discussion due to competition and disagreement, to see whether the "cake" can be expanded, in terms of the water itself and of benefits that can accrue from a creative water agreement. - Conversion of "potential" water into "usable" water: water in a source requires transformation in time, space and quality and incurs a cost. - Introduction of expanded, previously unused resources which become available due to advanced extraction/production capabilities and additional treatment process, and/or by changing water use patterns and land use practices. - Negotiate over and jointly manage the benefits and losses due to water (wherever and whenever possible) rather than merely with the physical parameters of water themselves volume, flow, concentration.

Application of Nemerow Index Method and Integrated Water Quality Index Method in Water Quality Assessment of Zhangze Reservoir

NASA Astrophysics Data System (ADS)

Zhang, Qian; Feng, Minquan; Hao, Xiaoyan

2018-03-01

[Objective] Based on the water quality historical data from the Zhangze Reservoir from the last five years, the water quality was assessed by the integrated water quality identification index method and the Nemerow pollution index method. The results of different evaluation methods were analyzed and compared and the characteristics of each method were identified.[Methods] The suitability of the water quality assessment methods were compared and analyzed, based on these results.[Results] the water quality tended to decrease over time with 2016 being the year with the worst water quality. The sections with the worst water quality were the southern and northern sections.[Conclusion] The results produced by the traditional Nemerow index method fluctuated greatly in each section of water quality monitoring and therefore could not effectively reveal the trend of water quality at each section. The combination of qualitative and quantitative measures of the comprehensive pollution index identification method meant it could evaluate the degree of water pollution as well as determine that the river water was black and odorous. However, the evaluation results showed that the water pollution was relatively low.The results from the improved Nemerow index evaluation were better as the single indicators and evaluation results are in strong agreement; therefore the method is able to objectively reflect the water quality of each water quality monitoring section and is more suitable for the water quality evaluation of the reservoir.

Manipulative lowering of the water table during summer does not affect CO2 emissions and uptake in a fen in Germany.

PubMed

Muhr, Jan; Höhle, Juliane; Otieno, Dennis O; Borken, Werner

2011-03-01

We simulated the effect of prolonged dry summer periods by lowering the water table on three manipulation plots (D(1-3)) in a minerotrophic fen in southeastern Germany in three years (2006-2008). The water table at this site was lowered by drainage and by excluding precipitation; three nonmanipulated control plots (C(1-3)) served as a reference. We found no significant differences in soil respiration (R(Soil)), gross primary production (GPP), or aboveground respiration (R(AG)) between the C(1-3) and D(1-3) plots in any of the measurement years. The water table on the control plots was naturally low, with a median water table (2006-2008) of 8 cm below the surface, and even lower during summer when respiratory activity was highest, with median values (C(1-3)) between 11 and 19 cm below the surface. If it is assumed that oxygen availability in the uppermost 10 cm was not limited by the location of the water table, manipulative lowering of the water table most likely increased oxygen availability only in deeper peat layers where we expect R(Soil) to be limited by poor substrate quality rather than anoxia. This could explain the lack of a manipulation effect. In a second approach, we estimated the influence of the water table on R(Soil) irrespective of treatment. The results showed a significant correlation between R(Soil) and water table, but with R(Soil) decreasing at lower water tables rather than increasing. We thus conclude that decomposition in the litter layer is not limited by waterlogging in summer, and deeper peat layers bear no significant decomposition potential due to poor substrate quality. Consequently, we do not expect enhanced C losses from this site due to increasing frequency of dry summers. Assimilation and respiration of aboveground vegetation were not affected by water table fluctuations between 10 and >60 cm depth, indicating the lack of stress resulting from either anoxia (high water table) or drought (low water table).

The psychology of drinking water quality: An exploratory study

NASA Astrophysics Data System (ADS)

Syme, Geoffrey J.; Williams, Katrina D.

1993-12-01

Perceptions of drinking water quality were measured for residents at four locations in Western Australia. The total dissolved solid levels for the locations varied. Four scales of drinking water satisfaction were measured: acceptability of water quality; water quality risk judgment; perception of neighborhood water quality; and attitudes toward fluoride as an additive. Responses to each of these scales did not appear to be highly related to total dissolved solids. The relationship between attitudes toward water quality and a variety of psychological, attitudinal, experiential, and demographic variables was investigated. It was found that responses to the acceptability of water quality and water quality risk judgment scales related to perceived credibility of societal institutions and feelings of control over water quality and environmental problems. For the remaining two scales few significant correlations were found. The results support those who advocate localized information and involvement campaigns on drinking water quality issues.

40 CFR 130.3 - Water quality standards.

Code of Federal Regulations, 2010 CFR

2010-07-01

... QUALITY PLANNING AND MANAGEMENT § 130.3 Water quality standards. A water quality standard (WQS) defines the water quality goals of a water body, or portion thereof, by designating the use or uses to be made... 40 Protection of Environment 21 2010-07-01 2010-07-01 false Water quality standards. 130.3 Section...

Variable thickness transient ground-water flow model. Volume 3. Program listings

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

Reisenauer, A.E.

1979-12-01

The Assessment of Effectiveness of Geologic Isolation Systems (AEGIS) Program is developing and applying the methodology for assessing the far-field, long-term post-closure safety of deep geologic nuclear waste repositories. AEGIS is being performed by Pacific Northwest Laboratory (PNL) under contract with the Office of Nuclear Waste Isolation (OWNI) for the Department of Energy (DOE). One task within AEGIS is the development of methodology for analysis of the consequences (water pathway) from loss of repository containment as defined by various release scenarios. Analysis of the long-term, far-field consequences of release scenarios requires the application of numerical codes which simulate the hydrologicmore » systems, model the transport of released radionuclides through the hydrologic systems to the biosphere, and, where applicable, assess the radiological dose to humans. Hydrologic and transport models are available at several levels of complexity or sophistication. Model selection and use are determined by the quantity and quality of input data. Model development under AEGIS and related programs provides three levels of hydrologic models, two levels of transport models, and one level of dose models (with several separate models). This is the third of 3 volumes of the description of the VTT (Variable Thickness Transient) Groundwater Hydrologic Model - second level (intermediate complexity) two-dimensional saturated groundwater flow.« less

Effect of moisture sorption on the performance of crospovidone.

PubMed

Hiew, Tze Ning; Johan, Nur Atiqah Binte; Desai, Parind Mahendrakumar; Chua, Siang Meng; Loh, Zhi Hui; Heng, Paul Wan Sia

2016-11-30

Crospovidone is a commonly used tablet disintegrant. However, the synthetic disintegrant has been known to be hygroscopic and high moisture content in crospovidone used could exert deleterious effects on tablets formulated with it. The objective of this study was to elicit a better understanding between crospovidone-water interaction and its effect on disintegrant performance. Moisture sorption and desorption isotherms were obtained together with the enthalpy of immersion. Crospovidone samples stored at four relative humidities were used to formulate tablets and the resultant tablets were evaluated for their mechanical, dimensional and disintegratability attributes. Analyses of the moisture sorption isotherms indicated that externally adsorbed moisture accounted for the bulk of the total moisture content in crospovidone, with minimal amount of moisture absorbed intramolecularly. Enthalpy of immersion became less exothermic with crospovidone samples stored at increasing storage humidity. Correspondingly, improvement in disintegration time became less pronounced. This was postulated to be a consequence of premature wetting of the particle surfaces by externally adsorbed moisture. High humidity was also detrimental to tablet hardness and thickness. In conclusion, the impact of moisture sorption during storage by excipients such as crospovidone could be better understood by the appreciation of crospovidone-water interaction and its consequence on tablet quality. Copyright © 2016 Elsevier B.V. All rights reserved.

Association between perceptions of public drinking water quality and actual drinking water quality: A community-based exploratory study in Newfoundland (Canada).

PubMed

Ochoo, Benjamin; Valcour, James; Sarkar, Atanu

2017-11-01

Studying public perception on drinking water quality is crucial for managing of water resources, generation of water quality standards, and surveillance of the drinking-water quality. However, in policy discourse, the reliability of public perception concerning drinking water quality and associated health risks is questionable. Does the public perception of water quality equate with the actual water quality? We investigated public perceptions of water quality and the perceived health risks and associated with the actual quality of public water supplies in the same communities. The study was conducted in 45 communities of Newfoundland (Canada) in 2012. First, a telephone survey of 100 households was conducted to examine public perceptions of drinking water quality of their respective public sources. Then we extracted public water quality reports of the same communities (1988-2011) from the provincial government's water resources portal. These reports contained the analysis of 2091 water samples, including levels of Disinfection By-Products (DBPs), nutrients, metals, ions and physical parameters. The reports showed that colour, manganese, total dissolved solids, iron, turbidity, and DBPs were the major detected parameters in the public water. However, the majority of the respondents (>56%) were either completely satisfied or very satisfied with the quality of drinking water. Older, higher educated and high-income group respondents were more satisfied with water quality than the younger, less educated and low-income group respondents. The study showed that there was no association with public satisfaction level and actual water quality of the respective communities. Even, in the communities, supplied by the same water system, the respondents had differences in opinion. Despite the effort by the provincial government to make the water-test results available on its website for years, the study showed existing disconnectedness between public perception of drinking water quality and actual quality. We had little scope to explore the possible explanations, and hence further studies are required to verify the age, gender educational status and income differential about the satisfaction of public service like water supply. Copyright © 2017 Elsevier Inc. All rights reserved.

40 CFR 131.35 - Colville Confederated Tribes Indian Reservation.

Code of Federal Regulations, 2013 CFR

2013-07-01

... PROGRAMS WATER QUALITY STANDARDS Federally Promulgated Water Quality Standards § 131.35 Colville Confederated Tribes Indian Reservation. The water quality standards applicable to the waters within the... these Federal water quality standards to prescribe minimum water quality requirements for the surface...

[Study on the optimization of monitoring indicators of drinking water quality during health supervision].

PubMed

Ye, Bixiong; E, Xueli; Zhang, Lan

2015-01-01

To optimize non-regular drinking water quality indices (except Giardia and Cryptosporidium) of urban drinking water. Several methods including drinking water quality exceed the standard, the risk of exceeding standard, the frequency of detecting concentrations below the detection limit, water quality comprehensive index evaluation method, and attribute reduction algorithm of rough set theory were applied, redundancy factor of water quality indicators were eliminated, control factors that play a leading role in drinking water safety were found. Optimization results showed in 62 unconventional water quality monitoring indicators of urban drinking water, 42 water quality indicators could be optimized reduction by comprehensively evaluation combined with attribute reduction of rough set. Optimization of the water quality monitoring indicators and reduction of monitoring indicators and monitoring frequency could ensure the safety of drinking water quality while lowering monitoring costs and reducing monitoring pressure of the sanitation supervision departments.

A Review of Groundwater Arsenic Contamination in Bangladesh: The Millennium Development Goal Era and Beyond

PubMed Central

Yunus, Fakir Md.; Khan, Safayet; Chowdhury, Priyanka; Milton, Abul Hasnat; Hussain, Sumaira; Rahman, Mahfuzar

2016-01-01

Arsenic contamination in drinking water has a detrimental impact on human health which profoundly impairs the quality of life. Despite recognition of the adverse health implications of arsenic toxicity, there have been few studies to date to suggest measures that could be taken to overcome arsenic contamination. After the statement in 2000 WHO Bulletin that Bangladesh has been experiencing the largest mass poisoning of population in history, we researched existing literature to assess the magnitude of groundwater arsenic contamination in Bangladesh. The literature reviewed related research that had been initiated and/or completed since the implementation of the Millennium Development Goals (MDGs) under four domains: (1) extent of arsenic contamination; (2) health consequences; (3) mitigation and technologies and (4) future directions. To this means, a review matrix was established for analysis of previous literature based on these four core domains. Our findings revealed that several high-quality research articles were produced at the beginning of the MDG period, but efforts have dwindled in recent years. Furthermore, there were only a few studies conducted that focused on developing suitable solutions for managing arsenic contamination. Although the government of Bangladesh has made its population’s access to safe drinking water a priority agenda item, there are still pockets of the population that continue to suffer from arsenic toxicity due to contaminated water supplies. PMID:26891310

A Review of Groundwater Arsenic Contamination in Bangladesh: The Millennium Development Goal Era and Beyond.

PubMed

Yunus, Fakir Md; Khan, Safayet; Chowdhury, Priyanka; Milton, Abul Hasnat; Hussain, Sumaira; Rahman, Mahfuzar

2016-02-15

Arsenic contamination in drinking water has a detrimental impact on human health which profoundly impairs the quality of life. Despite recognition of the adverse health implications of arsenic toxicity, there have been few studies to date to suggest measures that could be taken to overcome arsenic contamination. After the statement in 2000 WHO Bulletin that Bangladesh has been experiencing the largest mass poisoning of population in history, we researched existing literature to assess the magnitude of groundwater arsenic contamination in Bangladesh. The literature reviewed related research that had been initiated and/or completed since the implementation of the Millennium Development Goals (MDGs) under four domains: (1) extent of arsenic contamination; (2) health consequences; (3) mitigation and technologies and (4) future directions. To this means, a review matrix was established for analysis of previous literature based on these four core domains. Our findings revealed that several high-quality research articles were produced at the beginning of the MDG period, but efforts have dwindled in recent years. Furthermore, there were only a few studies conducted that focused on developing suitable solutions for managing arsenic contamination. Although the government of Bangladesh has made its population's access to safe drinking water a priority agenda item, there are still pockets of the population that continue to suffer from arsenic toxicity due to contaminated water supplies.

A one-dimensional, steady-state, dissolved-oxygen model and waste-load assimilation study for Little Laughery Creek, Ripley and Franklin counties, Indiana

USGS Publications Warehouse

Crawford, Charles G.; Wilber, William G.; Peters, James G.

1980-01-01

A digital model calibrated to conditions in Little Laughery Creek triutary and Little Laughery Creek, Ripley and Franklin Counties, Ind., was used to predict alternatives for future waste loadings that would be compatible with Indiana stream water-quality standards defined for two critical hydrologic conditions, summer and winter low flows. Natural streamflow during the summer and annual 7-day, 10-year low flow is zero. Headwater flow upstream from the wastewater-treatment facilities consists solely of process cooling water from an industrial discharger. This flow is usually less than 0.5 cubic foot per second. Consequently, benefits from dilution are minimal. As a result, current and projected ammonia-nitrogen concentrations from the municipal discharges will result in in-stream ammonia-nitrogen concentrations that exceed the Indiana ammonia-nitrogen toxicity standards (maximum stream ammonia-nitrogen concentrations of 2.5 and 4.0 milligrams per liter during summer and winter low flows, respectively). Benthic-oxygen demand is probably the most significant factor affecting Little Laughery Creek and is probably responsible for the in-stream dissolved-oxygen concentration being less than the Indiana stream dissolved-oxygen standard (5.0 milligrams per liter) during two water-quality surveys. After municipal dischargers complete advanced waste-treatment facilities, benthic-oxygen demand should be less significant in the stream dissolved-oxygen dynamics. (USGS)

Chesapeake Bay Watershed - Protecting the Chesapeake Bay and its rivers through science, restoration, and partnership

USGS Publications Warehouse

,

2012-01-01

The Chesapeake Bay, the Nation's largest estuary, has been degraded due to the impact of human-population increase, which has doubled since 1950, resulting in degraded water quality, loss of habitat, and declines in populations of biological communities. Since the mid-1980s, the Chesapeake Bay Program (CBP), a multi-agency partnership which includes the Department of Interior (DOI), has worked to restore the Bay ecosystem. The U.S. Geological Survey (USGS) has the critical role of providing unbiased scientific information that is utilized to document and understand ecosystem change to help assess the effectiveness of restoration strategies in the Bay and its watershed. The USGS revised its Chesapeake Bay science plan for 2006-2011 to address the collective needs of the CBP, DOI, and USGS with a mission to provide integrated science for improved understanding and management of the Bay ecosystem. The USGS science themes for this mission are: Causes and consequences of land-use change; Impact of climate change and associated hazards; Factors affecting water quality and quantity; Ability of habitat to support fish and bird populations; and Synthesis and forecasting to improve ecosystem assessment, conservation, and restoration.

Groundwater quality in the San Diego Drainages Hydrogeologic Province, California

USGS Publications Warehouse

Wright, Michael T.; Belitz, Kenneth

2011-01-01

More than 40 percent of California's drinking water is from groundwater. To protect this vital resource, the State of California created the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The Priority Basin Project of the GAMA Program provides a comprehensive assessment of the State's groundwater quality and increases public access to groundwater-quality information. The San Diego Drainages Hydrogeologic Province (hereinafter referred to as San Diego) is one of the study units being evaluated. The San Diego study unit is approximately 3,900 square miles and consists of the Temecula Valley, Warner Valley, and 12 other alluvial basins (California Department of Water Resources, 2003). The study unit also consists of all areas outside defined groundwater basins that are within 3 kilometers of a public-supply well. The study unit was separated, based primarily on hydrogeologic settings, into four study areas: Temecula Valley, Warner Valley, Alluvial Basins, and Hard Rock (Wright and others, 2005). The sampling density for the Hard Rock study area, which consists of areas outside of groundwater basins, was much lower than for the other study areas. Consequently, aquifer proportions for the Hard Rock study area are not used to calculate the aquifer proportions shown by the pie charts. An assessment of groundwater quality for the Hard Rock study area can be found in Wright and Belitz, 2011. The temperatures in the coastal part of the study unit are mild with dry summers, moist winters, and an average annual rainfall of about 10 inches. The temperatures in the mountainous eastern part of the study unit are cooler than in the coastal part, with an annual precipitation of about 45 inches that occurs mostly in the winter. The primary aquifers consist of Quaternary-age alluvium and weathered bedrock in the Temecula Valley, Warner Valley, and Alluvial Basins study areas, whereas in the Hard Rock study area the primary aquifers consist mainly of fractured and decomposed granite of Mesozoic age. The primary aquifers are defined as those parts of the aquifers corresponding to the perforated intervals of wells listed in the California Department of Public Health (CDPH) database. Public-supply wells typically are drilled to depths between 200 and 700 feet, consist of solid casing from the land surface to a depth of about 60 to 170 feet, and are perforated, or consist of an open hole, below the solid casing. Water quality in the shallow and deep parts of the aquifer system may differ from water quality in the primary aquifers. Municipal water use accounts for approximately 70 percent of water used in the study unit; the majority of the remainder is used for agriculture, industry, and commerce. Groundwater accounts for approximately 8 percent of the municipal supply, and surface water, the majority of which is imported, accounts for the rest. Recharge to groundwater occurs through stream-channel infiltration from rivers and their tributaries, infiltration in engineered recharge basins, and infiltration of water from precipitation and irrigation. The primary source of discharge is water pumped from wells.

Sustaining Waters: From Hydrology to Drinking Water

NASA Astrophysics Data System (ADS)

Toch, S.

2003-04-01

Around the world, disastrous effects of floods and droughts are painful evidence of our continuing struggle between human resource demands and the sustainability of our hydrologic systems. Too much or too little rainfall is often deemed the culprit in these water crises, focussing on water "lacks and needs" instead of exploring the mechanisms of the hydrologic functions and processes that sustain us. Applicable to regions around the world, this unified approach is about our human and environmental qualities with user friendly concepts and how-to guides backed up by real life experiences. From the poorest parts of Africa to Urban France to the wealthest state in the USA, examples from surface to groundwater to marine environments demonstrate how the links between vulerable natural areas, and the basins that they support are integral to the availability, adequacy and accessibility of our drinking water. Watershed management can be an effective means for crisis intervention and pollution control. This project is geared as a reference for groups, individuals and agencies concerned with watershed management, a supplement for interdisciplinary high school through university curriculam, for professional development in technical and field assistance, and for community awareness in the trade-offs and consequences of resource decisions that affect hydrologic systems. This community-based project demonstrates how our human resource demands can be managed within ecological constraints. An inter-disciplinary process is developed that specifically assesses risk to human health from resource use practices, and explores the similarities and interations between our human needs and those of the ecosystems in which we all must live together. Disastrous conditions worldwide have triggered reactions in crisis relief rather than crisis prevention. Through a unified management approach to the preservation of water quality, the flows of water that connect all water users can serve as a basis for the maintenance and protection of our valuable watersheds.

40 CFR 130.3 - Water quality standards.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 23 2012-07-01 2012-07-01 false Water quality standards. 130.3 Section 130.3 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS WATER QUALITY PLANNING AND MANAGEMENT § 130.3 Water quality standards. A water quality standard (WQS) defines...

40 CFR 130.3 - Water quality standards.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 22 2014-07-01 2013-07-01 true Water quality standards. 130.3 Section 130.3 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS WATER QUALITY PLANNING AND MANAGEMENT § 130.3 Water quality standards. A water quality standard (WQS) defines...

40 CFR 130.3 - Water quality standards.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 23 2013-07-01 2013-07-01 false Water quality standards. 130.3 Section 130.3 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS WATER QUALITY PLANNING AND MANAGEMENT § 130.3 Water quality standards. A water quality standard (WQS) defines...

40 CFR 130.3 - Water quality standards.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 22 2011-07-01 2011-07-01 false Water quality standards. 130.3 Section 130.3 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS WATER QUALITY PLANNING AND MANAGEMENT § 130.3 Water quality standards. A water quality standard (WQS) defines...

Hydrology and cycling of nitrogen and phosphorus in Little Bean Marsh : a remnant riparian wetland along the Missouri River in Platte County, Missouri, 1996-97

USGS Publications Warehouse

Blevins, Dale W.

2004-01-01

The lack of concurrent water-quality and hydrologic data on riparian wetlands in the Midwestern United States has resulted in a lack of knowledge about the water-quality functions that these wetlands provide. Therefore, Little Bean Marsh, a remnant riparian wetland along the Missouri River, was investigated in 1996 and 1997 primarily to determine the magnitude and character of selected water-quality benefits that can be produced in such a wetland and to identify critical processes that can be managed in remnant or restored riparian wetlands for amelioration of water quality. Little Bean Marsh averages 69 hectares in size, has a maximum depth of about 1 meter, and the majority of the marsh is covered by macrophytes. In 1997, 41 percent of the water received by Little Bean Marsh was from direct precipitation, 14 percent was from ground-water seepage, 30 percent from watershed runoff, and 15 percent was backflow from Bean Lake. Although, Little Bean Marsh was both a ground-water recharge and discharge area, discharge to the marsh was three times the recharge to ground water. Ground-water levels closely tracked marsh water levels indicating a strong hydraulic connection between ground water and the marsh. Reduced surface runoff and ground-water availability are stabilizing influences on marsh hydrology and probably contribute to the persistence of emergent vegetation. The rapid hydraulic connection between Little Bean Marsh and ground water indicates that the hydrologic regime of most wetlands along the lower Missouri River is largely a function of the altitude of the marsh bottom relative to the altitude of the water table. More water was lost from the marsh through evapotranspiration (59 percent) than all other pathways combined. This is partially because the transpiration process of abundant macrophytes can greatly contribute to the evapotranspiration above that lost from open water surfaces. Surface outflow accounted for 36 percent and ground-water seepage accounted for only 5 percent of the losses. Large residence times allows the marsh to greatly affect water quality before water escapes as ground-water recharge or surface outflow. The shallowness of Little Bean Marsh and ion exclusion during ice formation caused the highest specific conductances of 1,100 to 1,300 microsiemens per centimeter at 25 degrees Celsius to occur during the winter. This concentration of dissolved solutes under ice can make wetlands more vulnerable to toxic contaminants than deeper surface-water bodies. Dissolved oxygen was less than 5 mg/L (milligrams per liter) for 3 to 4 months and near 0 mg/L for about 1 month in summer. Despite depths of less than 1 meter, temperature stratification persisted more than 3 months during the summers of 1996 and 1997, preventing mixing and contributing to periods of anoxia. Shallow depths and extended periods of anoxia in the marsh limit the ability of some organisms to escape high-temperature stress. Turbidity in Little Bean Marsh usually was low for several reasons: sediment loadings from the largely flood-plain drainage were low, emergent vegetation shade out algae and shield the water from wind, and high concentrations of bivalent cations increase flocculation rates of inorganic suspended material. The high concentrations of bivalent cations was largely because of a substantial amount of ground-water seepage into the marsh. Dissolved organic nitrogen was the dominant nitrogen species in Little Bean Marsh. Denitrification and biotic uptake kept more than 62 percent of nitrate (NO3) and 43 percent of ammonium (NH4) concentrations in marsh samples less than a detection limit of 0.005 mg/L. This contrasts with the Missouri River where inorganic NO3 dominates. Consequently, artificial flood-plain drainage that bypasses riparian wetlands likely deliver substantially more biotically available inorganic nitrogen to receiving waters than surface water that has been routed through a remnant wetland. Aver

Water Quality of Hills Water, Supply Water and RO Water Machine at Ulu Yam Selangor

NASA Astrophysics Data System (ADS)

Ngadiman, N.; ‘I Bahari, N.; Kaamin, M.; Hamid, N. B.; Mokhtar, M.; Sahat, S.

2016-07-01

The rapid development resulted in the deterioration of the quality of drinking water in Malaysia. Recognizing the importance of water quality, new alternatives for drinking water such as mineral water processing from reverse osmosis (RO) machine become more popular. Hence, the demand for mineral water, natural spring water or water from the hills or mountains rose lately. More consumers believed the quality of these spring water better than other source of drinking water. However, the quality of all the drinking water sources is to meet the required quality standard. Therefore, this paper aims to measure the quality of the waters from hills, from RO machine and the water supply in Ulu Yam, Selangor Batang Kali, Malaysia. The water quality was determined based on following parameters: ammoniacal nitrogen (NH3), iron (Fe), turbidity (NTU) and pH. The results show that the water from hills has better quality compared to water supply and water from RO machine. The value of NH3 ranged from 0.03 mg/L- 0.67 mg/L; Fe was from 0.03mg/L - 0.12 mg/L, turbidity at 0.42 NTU - 0.88 NTU and pH is at 6.60 - 0.71. Based on the studied parameters, all three types of water are fit for drinking and have met the required national drinking water quality standard.

Evaluating benefits and costs of changes in water quality.

Treesearch

Jessica Koteen; Susan J. Alexander; John B. Loomis

2002-01-01

Water quality affects a variety of uses, such as municipal water consumption and recreation. Changes in water quality can influence the benefits water users receive. The problem is how to define water quality for specific uses. It is not possible to come up with one formal definition of water quality that fits all water uses. There are many parameters that influence...

Assessment of the effects of release variables on the consequences of LNG spillage onto water using FERC models.

PubMed

Qiao, Yuanhua; West, Harry H; Mannan, M Sam; Johnson, David W; Cornwell, John B

2006-03-17

Liquefied natural gas (LNG) release, spread, evaporation, and dispersion processes are illustrated using the Federal Energy Regulatory Commission models in this paper. The spillage consequences are dependent upon the tank conditions, release scenarios, and the environmental conditions. The effects of the contributing variables, including the tank configuration, breach hole size, ullage pressure, wind speed and stability class, and surface roughness, on the consequence of LNG spillage onto water are evaluated using the models. The sensitivities of the consequences to those variables are discussed.

18 CFR 801.7 - Water quality.

Code of Federal Regulations, 2010 CFR

2010-04-01

... water quality management and control. However, protection of the water resources of the basin from... quality program in the comprehensive plan. (c) The Commission's role in water quality management and... 18 Conservation of Power and Water Resources 2 2010-04-01 2010-04-01 false Water quality. 801.7...

40 CFR 130.6 - Water quality management plans.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 23 2012-07-01 2012-07-01 false Water quality management plans. 130.6 Section 130.6 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS WATER QUALITY PLANNING AND MANAGEMENT § 130.6 Water quality management plans. (a) Water quality management (WQM...

40 CFR 130.6 - Water quality management plans.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 23 2013-07-01 2013-07-01 false Water quality management plans. 130.6 Section 130.6 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS WATER QUALITY PLANNING AND MANAGEMENT § 130.6 Water quality management plans. (a) Water quality management (WQM...

40 CFR 130.6 - Water quality management plans.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 22 2014-07-01 2013-07-01 true Water quality management plans. 130.6 Section 130.6 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS WATER QUALITY PLANNING AND MANAGEMENT § 130.6 Water quality management plans. (a) Water quality management (WQM...

Scaling issues in sustainable river basin management

NASA Astrophysics Data System (ADS)

Timmerman, Jos; Froebich, Jochen

2014-05-01

Sustainable river basin management implies considering the whole river basin when managing the water resources. Management measures target at dividing the water over different uses (nature, agriculture, industry, households) thereby avoiding calamities like having too much, too little or bad quality water. Water management measures are taken at the local level, usually considering the sub-national and sometimes national effects of such measures. A large part of the world's freshwater resources, however, is contained in river basins and groundwater systems that are shared by two or more countries. Sustainable river basin management consequently has to encompass local, regional, national and international scales. This requires coordination over and cooperation between these levels that is currently compressed into the term 'water governance' . Governance takes into account that a large number of stakeholders in different regimes (the principles, rules and procedures that steer management) contribute to policy and management of a resource. Governance includes the increasing importance of basically non-hierarchical modes of governing, where non-state actors (formal organizations like NGOs, private companies, consumer associations, etc.) participate in the formulation and implementation of public policy. Land use determines the run-off generation and use of irrigation water. Land use is increasingly determined by private sector initiatives at local scale. This is a complicating factor in the governance issue, as in comparison to former developments of large scale irrigation systems, planning institutions at state level have then less insight on actual water consumption. The water management regime of a basin consequently has to account for the different scales of water management and within these different scales with both state and non-state actors. The central elements of regimes include the policy setting (the policies and water management strategies), legal setting (national and international laws and agreements), the institutional setting (the formal networks), information management (the information collection and dissemination system), and financing systems (the public and private sources that cover the water management costs). These elements are usually designed for a specific level and are ideally aligned with the other levels. The presentation will go into detail on connecting the different elements of the water management regime between different levels as well as on the overarching governance issues that play a role and will present opportunities and limitations of the linking options.

Optimizing MR imaging-guided navigation for focused ultrasound interventions in the brain

NASA Astrophysics Data System (ADS)

Werner, B.; Martin, E.; Bauer, R.; O'Gorman, R.

2017-03-01

MR imaging during transcranial MR imaging-guided Focused Ultrasound surgery (tcMRIgFUS) is challenging due to the complex ultrasound transducer setup and the water bolus used for acoustic coupling. Achievable image quality in the tcMRIgFUS setup using the standard body coil is significantly inferior to current neuroradiologic standards. As a consequence, MR image guidance for precise navigation in functional neurosurgical interventions using tcMRIgFUS is basically limited to the acquisition of MR coordinates of salient landmarks such as the anterior and posterior commissure for aligning a stereotactic atlas. Here, we show how improved MR image quality provided by a custom built MR coil and optimized MR imaging sequences can support imaging-guided navigation for functional tcMRIgFUS neurosurgery by visualizing anatomical landmarks that can be integrated into the navigation process to accommodate for patient specific anatomy.

Nanotechnology for a safe and sustainable water supply: enabling integrated water treatment and reuse.

PubMed

Qu, Xiaolei; Brame, Jonathon; Li, Qilin; Alvarez, Pedro J J

2013-03-19

Ensuring reliable access to clean and affordable water is one of the greatest global challenges of this century. As the world's population increases, water pollution becomes more complex and difficult to remove, and global climate change threatens to exacerbate water scarcity in many areas, the magnitude of this challenge is rapidly increasing. Wastewater reuse is becoming a common necessity, even as a source of potable water, but our separate wastewater collection and water supply systems are not designed to accommodate this pressing need. Furthermore, the aging centralized water and wastewater infrastructure in the developed world faces growing demands to produce higher quality water using less energy and with lower treatment costs. In addition, it is impractical to establish such massive systems in developing regions that currently lack water and wastewater infrastructure. These challenges underscore the need for technological innovation to transform the way we treat, distribute, use, and reuse water toward a distributed, differential water treatment and reuse paradigm (i.e., treat water and wastewater locally only to the required level dictated by the intended use). Nanotechnology offers opportunities to develop next-generation water supply systems. This Account reviews promising nanotechnology-enabled water treatment processes and provides a broad view on how they could transform our water supply and wastewater treatment systems. The extraordinary properties of nanomaterials, such as high surface area, photosensitivity, catalytic and antimicrobial activity, electrochemical, optical, and magnetic properties, and tunable pore size and surface chemistry, provide useful features for many applications. These applications include sensors for water quality monitoring, specialty adsorbents, solar disinfection/decontamination, and high performance membranes. More importantly, the modular, multifunctional and high-efficiency processes enabled by nanotechnology provide a promising route both to retrofit aging infrastructure and to develop high performance, low maintenance decentralized treatment systems including point-of-use devices. Broad implementation of nanotechnology in water treatment will require overcoming the relatively high costs of nanomaterials by enabling their reuse and mitigating risks to public and environmental health by minimizing potential exposure to nanoparticles and promoting their safer design. The development of nanotechnology must go hand in hand with environmental health and safety research to alleviate unintended consequences and contribute toward sustainable water management.

40 CFR 130.6 - Water quality management plans.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 21 2010-07-01 2010-07-01 false Water quality management plans. 130.6... QUALITY PLANNING AND MANAGEMENT § 130.6 Water quality management plans. (a) Water quality management (WQM... and certified and approved updates to those plans. Continuing water quality planning shall be based...

40 CFR 130.6 - Water quality management plans.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 22 2011-07-01 2011-07-01 false Water quality management plans. 130.6... QUALITY PLANNING AND MANAGEMENT § 130.6 Water quality management plans. (a) Water quality management (WQM... when they are needed to address water quality problems. (1) Total maximum daily loads. TMDLs in...

Trusted Advisors, Decision Models and Other Keys to Communicating Science to Decision Makers

NASA Astrophysics Data System (ADS)

Webb, E.

2006-12-01

Water resource management decisions often involve multiple parties engaged in contentious negotiations that try to navigate through complex combinations of legal, social, hydrologic, financial, and engineering considerations. The standard approach for resolving these issues is some form of multi-party negotiation, a formal court decision, or a combination of the two. In all these cases, the role of the decision maker(s) is to choose and implement the best option that fits the needs and wants of the community. However, each path to a decision carries the risk of technical and/or financial infeasibility as well as the possibility of unintended consequences. To help reduce this risk, decision makers often rely on some type of predictive analysis from which they can evaluate the projected consequences of their decisions. Typically, decision makers are supported in the analysis process by trusted advisors who engage in the analysis as well as the day to day tasks associated with multi-party negotiations. In the case of water resource management, the analysis is frequently a numerical model or set of models that can simulate various management decisions across multiple systems and output results that illustrate the impact on areas of concern. Thus, in order to communicate scientific knowledge to the decision makers, the quality of the communication between the analysts, the trusted advisor, and the decision maker must be clear and direct. To illustrate this concept, a multi-attribute decision analysis matrix will be used to outline the value of computer model-based collaborative negotiation approaches to guide water resources decision making and communication with decision makers. In addition, the critical role of the trusted advisor and other secondary participants in the decision process will be discussed using examples from recent water negotiations.

Spatial-Temporal Variations of Water Quality and Its Relationship to Land Use and Land Cover in Beijing, China

PubMed Central

Chen, Xiang; Zhou, Weiqi; Pickett, Steward T. A.; Li, Weifeng; Han, Lijian

2016-01-01

Rapid urbanization with intense land use and land cover (LULC) change and explosive population growth has a great impact on water quality. The relationship between LULC characteristics and water quality provides important information for non-point sources (NPS) pollution management. In this study, we first quantified the spatial-temporal patterns of five water quality variables in four watersheds with different levels of urbanization in Beijing, China. We then examined the effects of LULC on water quality across different scales, using Pearson correlation analysis, redundancy analysis, and multiple regressions. The results showed that water quality was improved over the sampled years but with no significant difference (p > 0.05). However, water quality was significantly different among nonurban and both exurban and urban sites (p < 0.05). Forest land was positively correlated with water quality and affected water quality significantly (p < 0.05) within a 200 m buffer zone. Impervious surfaces, water, and crop land were negatively correlated with water quality. Crop land and impervious surfaces, however, affected water quality significantly (p < 0.05) for buffer sizes greater than 800 m. Grass land had different effects on water quality with the scales. The results provide important insights into the relationship between LULC and water quality, and thus for controlling NPS pollution in urban areas. PMID:27128934

Quality-assurance and data-management plan for water-quality activities in the Kansas Water Science Center, 2014

USGS Publications Warehouse

Rasmussen, Teresa J.; Bennett, Trudy J.; Foster, Guy M.; Graham, Jennifer L.; Putnam, James E.

2014-01-01

As the Nation’s largest water, earth, and biological science and civilian mapping information agency, the U.S. Geological Survey is relied on to collect high-quality data, and produce factual and impartial interpretive reports. This quality-assurance and data-management plan provides guidance for water-quality activities conducted by the Kansas Water Science Center. Policies and procedures are documented for activities related to planning, collecting, storing, documenting, tracking, verifying, approving, archiving, and disseminating water-quality data. The policies and procedures described in this plan complement quality-assurance plans for continuous water-quality monitoring, surface-water, and groundwater activities in Kansas.

40 CFR 131.21 - EPA review and approval of water quality standards.

Code of Federal Regulations, 2010 CFR

2010-07-01

... (CONTINUED) WATER PROGRAMS WATER QUALITY STANDARDS Procedures for Review and Revision of Water Quality Standards § 131.21 EPA review and approval of water quality standards. (a) After the State submits its... analysis. (b) The Regional Administrator's approval or disapproval of a State water quality standard shall...

Relationship between Hydrodynamic Conditions and Water Quality in Landscape Water Body

NASA Astrophysics Data System (ADS)

Kang, Mengxin; Tian, Yimei; Zhang, Haiya; Wang, Dehong

2018-01-01

The urban landscape water usually lacks necessary water cycle and water speed is closed to zero, which easily lead to eutrophication in water system and deterioration of water quality. Therefore, understanding the impact of water circulation on the water quality is of great significance. With that significance, this research has been done to investigate the relationship between hydrodynamic conditions and water quality of urban landscape water based on adopted water quality indexes such as chemical oxygen demand (COD), total nitrogen (TN), total phosphorus (TP) and nitrogen-ammonia (NH3-N). Moreover, MIKE 21 model is used to simulate the hydrodynamics and water quality under different cases in an urban landscape lake. The results of simulation show that water circulation system could effectively improve current speeds, reduce the proportion of stagnation area, and solve the problem of water quality deterioration caused by reclaimed water in the lake.

Demonstration Tokamak Hybrid Reactor (DTHR) blanket design study, December 1978

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

Not Available

1978-01-01

This work represents only the second iteration of the conceptual design of a DTHR blanket; consequently, a number of issues important to a detailed blanket design have not yet been evaluated. The most critical issues identified are those of two-phase flow maldistribution, flow instabilities, flow stratification for horizontal radial inflow of boiling water, fuel rod vibrations, corrosion of clad and structural materials by high quality steam, fretting and cyclic loads. Approaches to minimizing these problems are discussed and experimental testing with flow mock-ups is recommended. These implications on a commercial blanket design are discussed and critical data needs are identified.

Characterization of environmental quality of forest fragments changes in Jundiaí-Mirim river basin-Brazil using the Markov Chain model

NASA Astrophysics Data System (ADS)

Hasimoto Fengler, Felipe; Leite de Moraes, Jener Fernando; Irio Ribeiro, Admilson; Peche Filho, Afonso; Araujo de Medeiros, Gerson; Baldin Damame, Desirée; Márcia Longo, Regina

2015-04-01

In Brazil is common practice the concurrency of large urban centers water catchment in distant sites. There's no policy to preserve strategic springs in the urban territory. Thus, rural areas, located in the surrounds of municipals, usually provide water and others environment services to the population that reside on cities. The Jundiaí-Mirim river basin, located in the most urbanized state in Brazil, São Paulo, composes an interesting example of this situation. It is located in a rural area near large urban centers, with large industrial parks, near the capital of state. As result of expansion of the cities on its surrounds their lands have had a historic of monetary valorization, making its territories attractive to the housing market. Consequently, the region has an intense process of urbanization that resulted in an increasing environmental disturbance in the areas of natural vegetation. In the other hand, the watershed is the principal water supplier of Jundiaí city, and houses forest remaining of an important Biome in Brazil, the Atlantic Rain Forest. Given the need to preserve its water production capacity and the forest remnants there, this study modeled the environmental quality of forest fragments through indicators of disturbance and evaluated the changes that occur between 1972 and 2013 using the Markov Chain model. The environment quality was determined by nine indicators of environmental disturbance (distance of urban areas, roads, edge land use, size, distance of others forest fragments, land capacity of use, watershed forest cover, number of forest fragments in the watersheds, shape of the forest fragment), obtained by techniques of Geoprocessing, and integrated by Multicriteria Analysis. The Markov Chain model showed a constant tendency of deteriorating in natural vegetation environmental quality, attributed to the intense process of occupation of the river basin. The results showed a historical trend of transformation in forest fragments with very low environmental quality to others uses and a static behavior of forest fragments with high environmental quality. It was explained by the tendency of occupation in forest fragments near urban areas, roads, with small size and high perturbation, and difficulties in occupation of forest fragments with high size, isolated from urban areas end roads. It was concluded that: (a) urbanization and deforestation of natural vegetation were primarily responsible for changes in environmental quality; (b) there is a need to create public policies to preserve the natural vegetation in the Jundiaí-Mirim river basin.

Water quality . . . potential sources of pollution

USGS Publications Warehouse

Vandas, Stephen; Farrar, Frank

1996-01-01

What is water quality? To most students, water quality may suggest only "clean" water for drinking, swimming, and fishing. But to the farmer or manufacturer, water quality may have an entirely different meaning. One of the most important issues concerning the quality of water is how that water will be used. Water that is perfectly fine for irrigation might not be suitable for drinking or swimming.

Integrated water cycle planning for towns in New South Wales, Australia.

PubMed

Schneider, P; Davison, A; Langdon, A; Freeman, G; Essery, C; Beatty, R; Toop, P

2003-01-01

Integration means different things to different people and as a consequence appears to only partially deliver on promised outcomes. For effective integrated water cycle management these outcomes should include improved water use efficiency, less waste, environmental sustainability, and provide secure and reliable supply to meet social and economic needs. The objective of integration is the management and combination of all these outcomes as part of a whole, so as to provide better outcomes than would be expected by managing the parts independently. Integration is also a consequence of the Water Reforms embarked on by the NSW State Government in 1995. The key goals of the reforms are clean and healthy rivers and groundwaters, and the establishment of more secure water entitlements for users. They are also essential for meeting the Council of Australian Government (COAG) water management strategies. The policies and guidelines that formed the NSW Water Reforms were the basis of the Water Management Act 2000 (NSW) (WMA) which is the legislative framework for water management in NSW. The NSW Department of Land and Water Conservation has developed an approach to integrated water cycle management for rural centres in NSW based on a catchment and policy context. This approach includes consideration of catchment wide needs and issues, environmental sustainability, government policy and community objectives in the development of an integrated water cycle plan. The approach provides for a transparent assessment of priorities and how to deal with them, and while specific to urban centres, could easily be expanded for use in the management of the whole of the catchment water cycle. Integration of the water cycle is expected to offer benefits to the local environment, community and economy. For instance, any unused proportion of an urban centre's water entitlement, or an offset against this entitlement created through returned flows (such as via good quality sewage effluent discharge to a river), can provide a surplus which is available to be traded on an annual basis. Further, improved demand management within an urban centre can be expected to result in a reduction in abstraction against the licence entitlement. This may result in the increased availability of in-stream water for environmental or other purposes and is expected to increase the economic value of returned water. Improved water use efficiencies are also expected to result in reduced capital works (and their associated costs) as the efficiency of service delivery and resource use improves. In this paper an example of the application of this process is provided and the outcomes discussed.

Water-Quality Characteristics for Sites in the Tongue, Powder, Cheyenne, and Belle Fourche River Drainage Basins, Wyoming and Montana, Water Years 2001-05, with Temporal Patterns of Selected Long-Term Water-Quality Data

USGS Publications Warehouse

Clark, Melanie L.; Mason, Jon P.

2007-01-01

Water-quality sampling was conducted regularly at stream sites within or near the Powder River structural basin in northeastern Wyoming and southeastern Montana during water years 2001-05 (October 1, 2000, to September 30, 2005) to characterize water quality in an area of coalbed natural gas development. The U.S. Geological Survey, in cooperation with the Wyoming Department of Environmental Quality, characterized the water quality at 22 sampling sites in the Tongue, Powder, Cheyenne, and Belle Fourche River drainage basins. Data for general hydrology, field measurements, major-ion chemistry, and selected trace elements were summarized, and specific conductance and sodium-adsorption ratios were evaluated for relations with streamflow and seasonal variability. Trend analysis for water years 1991-2005 was conducted for selected sites and constituents to assess change through time. Average annual runoff was highly variable among the stream sites. Generally, streams that have headwaters in the Bighorn Mountains had more runoff as a result of higher average annual precipitation than streams that have headwaters in the plains. The Powder River at Moorhead, Mont., had the largest average annual runoff (319,000 acre-feet) of all the sites; however, streams in the Tongue River drainage basin had the highest runoff per unit area of the four major drainage basins. Annual runoff in all major drainage basins was less than average during 2001-05 because of drought conditions. Consequently, water-quality samples collected during the study period may not represent long-term water-quality con-ditions for all sites. Water-quality characteristics were highly variable generally because of streamflow variability, geologic controls, and potential land-use effects. The range of median specific-conductance values among sites was smallest in the Tongue River drainage basin. Median values in that basin ranged from 643 microsiemens per centimeter at 25 degrees Celsius (?S/cm at 25?C) on the Tongue River to 1,460 ?S/cm at 25?C on Prairie Dog Creek. The Tongue River drainage basin has the largest percentage of area underlain by Mesozoic-age and older rocks and by more resistant rocks. In addition, the higher annual precipitation and a steeper gradient in this basin compared to basins in the plains produce relatively fast stream velocities, which result in a short contact time between stream waters and basin materials. The Powder River drainage basin, which has the largest drainage area and most diverse site conditions, had the largest range of median specific-conductance values among the four major drainage basins. Median values in that basin ranged from 680 ?S/cm at 25?C on Clear Creek to 5,950 ?S/cm at 25?C on Salt Creek. Median specific-conductance values among sites in the Cheyenne River drainage basin ranged from 1,850 ?S/cm at 25?C on Black Thunder Creek to 4,680 ?S/cm at 25?C on the Cheyenne River. The entire Cheyenne River drainage basin is in the plains, which have low precipitation, soluble geologic materials, and relatively low gradients that produce slow stream velocities and long contact times. Median specific-conductance values among sites in the Belle Fourche River drainage basin ranged from 1,740 ?S/cm at 25?C on Caballo Creek to 2,800 ?S/cm at 25?C on Donkey Creek. Water in the study area ranged from a magnesium-calcium-bicarbonate type for some sites in the Tongue River drainage basin to a sodium-sulfate type at many sites in the Powder, Cheyenne, and Belle Fourche River drainage basins. Little Goose Creek, Goose Creek, and the Tongue River in the Tongue River drainage basin, and Clear Creek in the Powder River drainage basin, which have headwaters in the Bighorn Mountains, consistently had the smallest median dissolved-sodium concentrations, sodium-adsorption ratios, dissolved-sulfate concentrations, and dissolved-solids concentrations. Salt Creek, Wild Horse Creek, Little Powder River, and the Cheyenne River, which have headwat

An innovative index for evaluating water quality in streams.

PubMed

Said, Ahmend; Stevens, David K; Sehlke, Gerald

2004-09-01

A water quality index expressed as a single number is developed to describe overall water quality conditions using multiple water quality variables. The index consists of water quality variables: dissolved oxygen, specific conductivity, turbidity, total phosphorus, and fecal coliform. The objectives of this study were to describe the preexisting indices and to define a new water quality index that has advantages over these indices. The new index was applied to the Big Lost River Watershed in Idaho, and the results gave a quantitative picture for the water quality situation. If the new water quality index for the impaired water is less than a certain number, remediation-likely in the form of total maximum daily loads or changing the management practices-may be needed. The index can be used to assess water quality for general beneficial uses. Nevertheless, the index cannot be used in making regulatory decisions, indicate water quality for specific beneficial uses, or indicate contamination from trace metals, organic contaminants, and toxic substances.

Water-quality assessment of the Smith River drainage basin, California and Oregon

USGS Publications Warehouse

Iwatsubo, Rick T.; Washabaugh, Donna S.

1982-01-01

A water-quality assessment of the Smith River drainage basin was made to provide a summary of the water-quality conditions including known or potential water-quality problems. Results of the study showed that the water quality of the Smith River is excellent and generally meets the water-quality objectives for the beneficial uses identified by the California Regional Water Quality Control Board, North Coast Region. Known and potential problems related to water quality include: Sedimentation resulting from both natural erosional processes and land-use activities such as timber harvest, road construction, and mining that accelerate the erosional processes; bacterial contamination of surface and ground waters from inundated septic tanks and drainfields, and grazing activities; industrial spills which have resulted in fish kills and oil residues; high concetrations of iron in ground water; log and debris jams creating fish migration barriers; and pesticide and trace-element contamination from timber-harvest and mining activities, respectively. Future studies are needed to establish: (1) a sustained long-term monitoring program to provide a broad coverage of water-quality conditions in order to define long-term water-quality trends; and (2) interpretive studies to determine the source of known and potential water-quality problems. (USGS)

Water quality assessment and meta model development in Melen watershed - Turkey.

PubMed

Erturk, Ali; Gurel, Melike; Ekdal, Alpaslan; Tavsan, Cigdem; Ugurluoglu, Aysegul; Seker, Dursun Zafer; Tanik, Aysegul; Ozturk, Izzet

2010-07-01

Istanbul, being one of the highly populated metropolitan areas of the world, has been facing water scarcity since the past decade. Water transfer from Melen Watershed was considered as the most feasible option to supply water to Istanbul due to its high water potential and relatively less degraded water quality. This study consists of two parts. In the first part, water quality data covering 26 parameters from 5 monitoring stations were analyzed and assessed due to the requirements of the "Quality Required of Surface Water Intended for the Abstraction of Drinking Water" regulation. In the second part, a one-dimensional stream water quality model with simple water quality kinetics was developed. It formed a basic design for more advanced water quality models for the watershed. The reason for assessing the water quality data and developing a model was to provide information for decision making on preliminary actions to prevent any further deterioration of existing water quality. According to the water quality assessment at the water abstraction point, Melen River has relatively poor water quality with regard to NH(4)(+), BOD(5), faecal streptococcus, manganese and phenol parameters, and is unsuitable for drinking water abstraction in terms of COD, PO(4)(3-), total coliform, total suspended solids, mercury and total chromium parameters. The results derived from the model were found to be consistent with the water quality assessment. It also showed that relatively high inorganic nitrogen and phosphorus concentrations along the streams are related to diffuse nutrient loads that should be managed together with municipal and industrial wastewaters. Copyright 2010 Elsevier Ltd. All rights reserved.

The impact of climate change on water provision under a low flow regime: a case study of the ecosystems services in the Francoli river basin.

PubMed

Marquès, Montse; Bangash, Rubab Fatima; Kumar, Vikas; Sharp, Richard; Schuhmacher, Marta

2013-12-15

Mediterranean basin is considered one of the most vulnerable regions of the world to climate change and with high probability to face acute water scarcity problem in the coming years. Francolí River basin (NE Spain), located in this vulnerable region is selected as a case study to evaluate the impact of climate change on the delivery of water considering the IPCC scenarios A2 and B1 for the time spans 2011-2040, 2041-2070 and 2071-2100. InVEST model is applied in a low flow river as a new case study, which reported successful results after its model validation. The studied hydrological ecosystem services will be highly impacted by climate change at Francolí River basin. Water yield is expected to be reduced between 11.5 and 44% while total drinking water provisioning will decrease between 13 and 50% having adverse consequences on the water quality of the river. Focusing at regional scale, Prades Mountains and Brugent Tributary provide most of the provision of water and also considered highly vulnerable areas to climate change. However, the most vulnerable part is the northern area which has the lowest provision of water. Francolí River basin is likely to experience desertification at this area drying Anguera and Vallverd tributaries. Copyright © 2013 Elsevier B.V. All rights reserved.

Renewable energy powered membrane technology: Impact of pH and ionic strength on fluoride and natural organic matter removal.

PubMed

Owusu-Agyeman, Isaac; Shen, Junjie; Schäfer, Andrea Iris

2018-04-15

Real water pH and ionic strength vary greatly, which influences the performance of membrane processes such as nanofiltration (NF) and reverse osmosis (RO). Systematic variation of pH (3-12) and ionic strength (2-10g/L as total dissolved solids (TDS)) was undertaken with a real Tanzanian water to investigate how water quality affects retention mechanisms of fluoride (F) and natural organic matter (NOM). An autonomous solar powered NF/RO system driven by a solar array simulator was supplied with constant power from a generator. An open NF (NF270) and a brackish water RO (BW30) membrane were used. A surface water with a very high F (59.7mg/L) and NOM (110mgC/L) was used. Retention of F by NF270 was <20% at pH <6, increased to 40% at pH6, and 60-70% at pH7-12, indicating a dominance of charge repulsion while being ineffective in meeting the guideline of 1.5mg/L. Increase in ionic strength led to a significant decline in retention of F (from 70 to 50%) and electrical conductivity (from 60 to 10%) by NF270, presumably due to charge screening. In contrast, BW30 retained about 50% of F at pH3, >80% at pH4, and about 99% at pH >5, due to the smaller pore size and hence a more dominant size exclusion. In consequence, only little impact of ionic strength increase was observed for BW30. The concentration of NOM in permeates of both NF270 and BW30 were typically <2mg/L. This was not affected by pH or ionic strength due to the fact that the bulk of NOM was rejected by both membranes through size exclusion. The research is carried out in the context of providing safe drinking water for rural and remote communities where infrastructure is lacking, and water quality varies significantly. While other studies focus on energy fluctuations, this research emphasises on feed water quality that affects system performance and may alter due to a number of environmental factors. Copyright © 2017 Elsevier B.V. All rights reserved.

Summary of surface-water quality, ground-water quality, and water withdrawals for the Spirit Lake Reservation, North Dakota

USGS Publications Warehouse

Vining, Kevin C.; Cates, Steven W.

2006-01-01

Available surface-water quality, ground-water quality, and water-withdrawal data for the Spirit Lake Reservation were summarized. The data were collected intermittently from 1948 through 2004 and were compiled from U.S. Geological Survey databases, North Dakota State Water Commission databases, and Spirit Lake Nation tribal agencies. Although the quality of surface water on the reservation generally is satisfactory, no surface-water sources are used for consumable water supplies. Ground water on the reservation is of sufficient quality for most uses. The Tokio and Warwick aquifers have better overall water quality than the Spiritwood aquifer. Water from the Spiritwood aquifer is used mostly for irrigation. The Warwick aquifer provides most of the consumable water for the reservation and for the city of Devils Lake. Annual water withdrawals from the Warwick aquifer by the Spirit Lake Nation ranged from 71 million gallons to 122 million gallons during 2000-04.

Water quality evaluation of Al-Gharraf river by two water quality indices

NASA Astrophysics Data System (ADS)

Ewaid, Salam Hussein

2017-11-01

Water quality of Al-Gharraf river, the largest branch of Tigris River south of Iraq, was evaluated by the National Sanitation Foundation Water Quality Index (NFS WQI) and the Heavy Metal Pollution Index (HPI) depending on 13 physical, chemical, and biological parameters of water quality measured monthly at ten stations on the river during 2015. The NSF-WQI range obtained for the sampling sites was 61-70 indicating a medium water quality. The HPI value was 98.6 slightly below the critical value for drinking water of 100, and the water quality in the upstream stations is better than downstream due to decrease in water and the accumulation of contaminants along the river. This study explains the significance of applying the water quality indices that show the aggregate impact of ecological factors in charge of water pollution of surface water and which permits translation of the monitoring data to assist the decision makers.

Open path measurements of carbon dioxide and water vapor under foggy conditions - technical problems, approaches and effects on flux measurements and budget calculations

NASA Astrophysics Data System (ADS)

El-Madany, T.; Griessbaum, F.; Maneke, F.; Chu, H.-S.; Wu, C.-C.; Chang, S. C.; Hsia, Y.-J.; Juang, J.-Y.; Klemm, O.

2010-07-01

To estimate carbon dioxide or water vapor fluxes with the Eddy Covariance method high quality data sets are necessary. Under foggy conditions this is challenging, because open path measurements are influenced by the water droplets that cross the measurement path as well as deposit on the windows of the optical path. For the LI-7500 the deposition of droplets on the window results in an intensity reduction of the infrared beam. To keep the strength of the infrared beam under these conditions, the energy is increased. A measure for the increased energy is given by the AGC value (Automatic Gain Control). Up to a AGC threshold value of 70 % the data from the LI-7500 is assumed to be of good quality (personal communication with LICOR). Due to fog deposition on the windows, the AGC value rises above 70 % and stays there until the fog disappears and the water on the windows evaporates. To gain better data quality during foggy conditions, a blower system was developed that blows the deposited water droplets off the window. The system is triggered if the AGC value rises above 70 %. Then a pneumatic jack will lift the blower system towards the LI-7500 and the water-droplets get blown off with compressed air. After the AGC value drops below 70 %, the pneumatic jack will move back to the idle position. Using this technique showed that not only the fog droplets on the window causing significant problems to the measurement, but also the fog droplets inside the measurement path. Under conditions of very dense fog the measured values of carbon dioxide can get unrealistically high, and for water vapor, negative values can be observed even if the AGC value is below 70 %. The negative values can be explained by the scatter of the infrared beam on the fog droplets. It is assumed, that different types of fog droplet spectra are causing the various error patterns observed. For high quality flux measurements, not only the AGC threshold value of 70 % is important, but also the fluctuation of the AGC value in a flux averaging interval. Such AGC value fluctuations can cause severe jumps in the concentration measurements that can hardly be corrected for. Results of fog effects on the LI-7500 performance and its consequences for flux measurements and budget calculations will be presented.

Comprehensive Flood Plain Studies Using Spatial Data Management Techniques.

DTIC Science & Technology

1978-06-01

Hydrologic Engineer- ing Center computer programs that forecast urban storm water quality and dynamic in- stream water quality response to waste...determination. Water Quality The water quality analysis planned for the pilot study includes urban storm water quality forecasting and in-streamn...analysis is performed under the direction of Tony Thomas. Chief, Research Branch, by Jess Abbott for storm water quality analysis, R. G. Willey for

Quagga and zebra mussels: biology, impacts, and control

USGS Publications Warehouse

Nalepa, Thomas F.; Schloesser, Don W.; Nalepa, Thomas F.; Schloesser, Don W.

2013-01-01

Quagga and Zebra Mussels: Biology, Impacts, and Control, Second Edition provides a broad view of the zebra/quagga mussel issue, offering a historic perspective and up-to-date information on mussel research. Comprising 48 chapters, this second edition includes reviews of mussel morphology, physiology, and behavior. It details mussel distribution and spread in Europe and across North America, and examines policy and regulatory responses, management strategies, and mitigation efforts. In addition, this book provides extensive coverage of the impact of invasive mussel species on freshwater ecosystems, including effects on water clarity, phytoplankton, water quality, food web changes, and consequences to other aquatic fauna. It also reviews and offers new insights on how zebra and quagga mussels respond and adapt to varying environmental conditions. This new edition includes seven video clips that complement chapter text and, through visual documentation, provide a greater understanding of mussel behavior and distribution.

Impact of urban and industrial effluents on the coastal marine environment in Oran, Algeria.

PubMed

Tayeb, A; Chellali, M R; Hamou, A; Debbah, S

2015-09-15

In Algeria most of the urban waste water is dumped without treatment into the Sea. It is tremendously important to assess the consequences of organic matter rich sewage on marine ecosystem. In this study we investigated the effects of industrial and urban sewage on the dissolved oxygen (O2), chemical oxygen demand (COD), biochemical oxygen demands (BOD5), pH, salinity, electrical conductivity (EC), Metal element (Hg, Pb, Cu, Ni, Cr, Cd), petroleum hydrocarbons (HC), oil and grease (OG) in Bay of Oran, Algeria. A ten-year follow-up research showed that the concentrations of oil and grease released into the bionetwork are of higher ecological impact and this needs to be given the desired consideration. Information on bathing water quality revealed that the most beaches in Oran are under the national environmental standard limit. Copyright © 2015 Elsevier Ltd. All rights reserved.

Microbial hitchhikers on marine plastic debris: Human exposure risks at bathing waters and beach environments.

PubMed

Keswani, Anisha; Oliver, David M; Gutierrez, Tony; Quilliam, Richard S

2016-07-01

Marine plastic debris is well characterized in terms of its ability to negatively impact terrestrial and marine environments, endanger coastal wildlife, and interfere with navigation, tourism and commercial fisheries. However, the impacts of potentially harmful microorganisms and pathogens colonising plastic litter are not well understood. The hard surface of plastics provides an ideal environment for opportunistic microbial colonisers to form biofilms and might offer a protective niche capable of supporting a diversity of different microorganisms, known as the "Plastisphere". This biotope could act as an important vector for the persistence and spread of pathogens, faecal indicator organisms (FIOs) and harmful algal bloom species (HABs) across beach and bathing environments. This review will focus on the existent knowledge and research gaps, and identify the possible consequences of plastic-associated microbes on human health, the spread of infectious diseases and bathing water quality. Copyright © 2016 Elsevier Ltd. All rights reserved.

Leaching properties of stabilised/solidified cement-admixtures-sewage sludges systems.

PubMed

Valls, S; Vàzquez, E

2002-01-01

One of the main objectives of this work is to present an effective alternative for the final destination of sludge from urban waste water treatment plants by its use as a component of mortar or concrete. A binding and stabilizing matrix of sludge-cement and sludge-cement-coal fly-ash was investigated and the effects of various percentages of waste and binder, on the behavior of sludge in the system are presented. Assessment of the environmental quality of the final product and the consequent guarantee of its use in the building industry demand that it meets a number of requisites, one of which is that the effluents extracted by water action should be contamination-free, or at least that the concentration of contaminants should be below certain pre-set limits. For this a number of leaching tests must be carried out, such as the Netherlands Leaching Test .

Trade-Off Between Dimethyl Sulfide and Isoprene Emissions from Marine Phytoplankton.

PubMed

Dani, K G Srikanta; Loreto, Francesco

2017-05-01

Marine phytoplankton emit volatile organic compounds (VOCs) such as dimethyl sulfide (DMS) and isoprene that influence air quality, cloud dynamics, and planetary albedo. We show that globally (i) marine phytoplankton taxa tend to emit either DMS or isoprene, and (ii) sea-water surface concentration and emission hotspots of DMS and isoprene have opposite latitudinal gradients. We argue that a convergence of antioxidant functions between DMS and isoprene is possible, driven by potential metabolic competition for photosynthetic substrates. Linking phytoplankton emission traits to their latitudinal niches, we hypothesize that natural selection favors DMS emission in cold (polar) waters and isoprene emission in warm (tropical) oceans, and that global warming may expand the geographic range of marine isoprene-emitters. A trade-off between DMS and isoprene at metabolic, organismal, and geographic levels may have important consequences for future marine biosphere-atmosphere interactions. Copyright © 2017 Elsevier Ltd. All rights reserved.

Intrinsic vulnerability, hazard and risk mapping for karst aquifers: A case study

NASA Astrophysics Data System (ADS)

Mimi, Ziad A.; Assi, Amjad

2009-01-01

SummaryGroundwater from karst aquifers is among the most important resources of drinking water supply of the worldwide population. The European COST action 620 proposed a comprehensive approach to karst groundwater protection, comprising methods of intrinsic and specific vulnerability mapping, hazard and risk mapping. This paper presents the first application of all components of this European approach to the groundwater underlying the Ramallah district, a karst hydrogeology system in Palestine. The vulnerability maps which were developed can assist in the implementation of groundwater management strategies to prevent degradation of groundwater quality. Large areas in the case study area can be classified as low or very low risk area corresponding to the pollution sources due to the absence of hazards and also due to low vulnerabilities. These areas could consequently be interesting for future development as they are preferable in view of ground water protection.

40 CFR 131.22 - EPA promulgation of water quality standards.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 21 2010-07-01 2010-07-01 false EPA promulgation of water quality standards. 131.22 Section 131.22 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS WATER QUALITY STANDARDS Procedures for Review and Revision of Water Quality Standards § 131.22 EPA promulgation of water quality...

40 CFR 131.22 - EPA promulgation of water quality standards.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 22 2011-07-01 2011-07-01 false EPA promulgation of water quality standards. 131.22 Section 131.22 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS WATER QUALITY STANDARDS Procedures for Review and Revision of Water Quality Standards § 131.22 EPA promulgation of water quality...

Successful integration efforts in water quality from the integrated Ocean Observing System Regional Associations and the National Water Quality Monitoring Network

USGS Publications Warehouse

Ragsdale, R.; Vowinkel, E.; Porter, D.; Hamilton, P.; Morrison, R.; Kohut, J.; Connell, B.; Kelsey, H.; Trowbridge, P.

2011-01-01

The Integrated Ocean Observing System (IOOS??) Regional Associations and Interagency Partners hosted a water quality workshop in January 2010 to discuss issues of nutrient enrichment and dissolved oxygen depletion (hypoxia), harmful algal blooms (HABs), and beach water quality. In 2007, the National Water Quality Monitoring Council piloted demonstration projects as part of the National Water Quality Monitoring Network (Network) for U.S. Coastal Waters and their Tributaries in three IOOS Regional Associations, and these projects are ongoing. Examples of integrated science-based solutions to water quality issues of major concern from the IOOS regions and Network demonstration projects are explored in this article. These examples illustrate instances where management decisions have benefited from decision-support tools that make use of interoperable data. Gaps, challenges, and outcomes are identified, and a proposal is made for future work toward a multiregional water quality project for beach water quality.

Water quality success stories: Integrated assessments from the IOOS regional associations and national water quality monitoring network

USGS Publications Warehouse

Ragsdale, Rob; Vowinkel, Eric; Porter, Dwayne; Hamilton, Pixie; Morrison, Ru; Kohut, Josh; Connell, Bob; Kelsey, Heath; Trowbridge, Phil

2011-01-01

The Integrated Ocean Observing System (IOOS®) Regional Associations and Interagency Partners hosted a water quality workshop in January 2010 to discuss issues of nutrient enrichment and dissolved oxygen depletion (hypoxia), harmful algal blooms (HABs), and beach water quality. In 2007, the National Water Quality Monitoring Council piloted demonstration projects as part of the National Water Quality Monitoring Network (Network) for U.S. Coastal Waters and their Tributaries in three IOOS Regional Associations, and these projects are ongoing. Examples of integrated science-based solutions to water quality issues of major concern from the IOOS regions and Network demonstration projects are explored in this article. These examples illustrate instances where management decisions have benefited from decision-support tools that make use of interoperable data. Gaps, challenges, and outcomes are identified, and a proposal is made for future work toward a multiregional water quality project for beach water quality.

Simulation of Water Quality in the Tull Creek and West Neck Creek Watersheds, Currituck Sound Basin, North Carolina and Virginia

USGS Publications Warehouse

Garcia, Ana Maria

2009-01-01

A study of the Currituck Sound was initiated in 2005 to evaluate the water chemistry of the Sound and assess the effectiveness of management strategies. As part of this study, the Soil and Water Assessment Tool (SWAT) model was used to simulate current sediment and nutrient loadings for two distinct watersheds in the Currituck Sound basin and to determine the consequences of different water-quality management scenarios. The watersheds studied were (1) Tull Creek watershed, which has extensive row-crop cultivation and artificial drainage, and (2) West Neck Creek watershed, which drains urban areas in and around Virginia Beach, Virginia. The model simulated monthly streamflows with Nash-Sutcliffe model efficiency coefficients of 0.83 and 0.76 for Tull Creek and West Neck Creek, respectively. The daily sediment concentration coefficient of determination was 0.19 for Tull Creek and 0.36 for West Neck Creek. The coefficient of determination for total nitrogen was 0.26 for both watersheds and for dissolved phosphorus was 0.4 for Tull Creek and 0.03 for West Neck Creek. The model was used to estimate current (2006-2007) sediment and nutrient yields for the two watersheds. Total suspended-solids yield was 56 percent lower in the urban watershed than in the agricultural watershed. Total nitrogen export was 45 percent lower, and total phosphorus was 43 percent lower in the urban watershed than in the agricultural watershed. A management scenario with filter strips bordering the main channels was simulated for Tull Creek. The Soil and Water Assessment Tool model estimated a total suspended-solids yield reduction of 54 percent and total nitrogen and total phosphorus reductions of 21 percent and 29 percent, respectively, for the Tull Creek watershed.

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.

Characteristics and Limitations of Submerged GPS L1 Observations

NASA Astrophysics Data System (ADS)

Steiner, Ladina; Geiger, Alain

2017-04-01

Extensive amount of water stored in snow covers has a high impact on flood development during snow melting periods. Early assessment of these parameters in mountain environments enhance early-warning and thus prevention of major impacts. Sub-snow GNSS techniques are lately suggested to determine liquid water content, snow water equivalent or considered for avalanche rescue. This technique is affordable, flexible, and provides accurate and continuous observations independent on weather conditions. However, the characteristics of GNSS observations for applications within a snow-pack still need to be further investigated. The magnitude of the main interaction processes involved for the GPS wavelength propagating through different layers of snow, ice or water is theoretically examined. Liquid water exerts the largest influence on GPS signal propagation through a snow-pack. Therefore, we focus on determining the characteristics of GNSS observables under water. An experiment was set-up to investigate the characteristics and limitations of submerged GPS observations using a pool, a level control by communicating pipes, a geodetic and a low-cost GPS antenna, and a water level sensor. The GPS antennas were placed into the water. The water level was increased daily by a step of two millimeters up to thirty millimeters above the antenna. Based on this experiment, the signal penetration depth, satellite availability, the attenuation of signal strength and the quality of solutions are analyzed. Our experimental results show an agreement with the theoretically derived attenuation parameter and signal penetration depth. The assumption of water as the limiting parameter for GPS observations within a snow-pack can be confirmed. Higher wetness in a snow-pack leads to less transmission, higher refraction, higher attenuation and thus a decreased penetration depth as well as a reduced quality of the solutions. In consequence, GPS applications within a snow-pack are heavily impacted by wetness which is even more pronounced during melting period. In this poster, we present a short introduction to the principle, explain the developed algorithms and show results of experiments dedicated to the signal propagation in water.

Water quality evaluation system to assess the status and the suitability of the Citarum river water to different uses.

PubMed

Fulazzaky, Mohamad Ali

2010-09-01

Water quality degradation in the Citarum river will increase from the year to year due to increasing pollutant loads when released particularly from Bandung region of the upstream areas into the river without treatment. This will be facing the problems on water quality status to use for multi-purposes in the downstream areas. The water quality evaluation system is used to evaluate the available water condition that distinguishes into two categories, i.e., the water quality index (WQI) and water quality aptitude (WQA). The assessment of water quality for the Citarum river from 10 selected stations was found that the WQI situates in the bad category generally and the WQA ranges from the suitable quality for agriculture and livestock watering uses to the unsuitable for biological potential function, drinking water production, and leisure activities and sports in the upstream areas of Saguling dam generally.

Preface to volume 1: status and trends of water quality worldwide

USGS Publications Warehouse

Larsen, Matthew C.; Ahuja, Satinder; Eimers, Jo Leslie; Edited by Ahuja, Satinder

2013-01-01

Water quality and water quantity are closely linked. In all regions of the world, the quality and quantity of water must be considered together in order to sustain abundant water of the quality needed for drinking, irrigation, environmental health, industry, power generation, and recreation. Protecting and managing water to meet water needs requires comprehensive information and understanding of the impacts of natural settings and anthropogenic activities on water quality.

75 FR 41106 - Amendments to the Water Quality Regulations, Water Code and Comprehensive Plan to Update Water...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-07-15

... (also called water quality criteria) for human health and aquatic life for toxic pollutants in the... Commission in 1996 adopted water quality criteria for human health and aquatic life for Water Quality Zones 2... Objectives for Toxic Pollutants for the Protection of Aquatic Life'', Table 6, ``Stream Quality Objectives...

Ground-water quality assessment of the central Oklahoma aquifer, Oklahoma - Analysis of available water-quality data through 1987

USGS Publications Warehouse

Parkhurst, David L.; Christenson, Scott C.; Schlottmann, Jamie L.

1989-01-01

Beginning in 1986, the Congress annually has appropriated funds for the U.S. Geological Survey to test and refine concepts for a National Water-Quality Assessment (NAWQA) Program. The long-term goals of a full-scale program would be to:Provide a nationally consistent description of current water-quality conditions for a large part of the Nation's surface- and ground-water resources;Define long-term trends (or lack of trends) in water quality; andIdentify, describe, and explain, as possible, the major factors that affect the observed water-quality conditions and trends.The results of the NAWQA Program will be made available to water managers, policy makers, and the public, and will provide an improved scientific basis for evaluating the effectiveness of water-quality management programs.At present (1988), the assessment program is in a pilot phase in seven project areas throughout the country that represent diverse hydrologic environments and water-quality conditions. The Central Oklahoma aquifer project is one of three pilot ground-water projects. One of the initial activities performed by each pilot project was to compile, screen, and interpret the large amount of water-quality data available within each study unit.The purpose of this report is to assess the water quality of the Central Oklahoma aquifer using the information available through 1987. The scope of the work includes compiling data from Federal, State, and local agencies; evaluating the suitability of the information for conducting a regional water-quality assessment; mapping regional variations in major-ion chemistry; calculating summary statistics of the available water-quality data; producing maps to show the location and number of samples that exceeded water-quality standards; and performing contingency-table analyses to determine the relation of geologic unit and depth to the occurrence of chemical constituents that exceed water-quality standards. This report provides an initial description of water-quality conditions in the Central Oklahoma aquifer study unit. No attempt was made in this report to determine the causes for regional variations in major-ion chemistry or to examine the reasons that some chemical constituents exceed water-quality standards.