2005-01-01
Nutrient- Related Water-Quality Improvements in the Thames River Basin, Connecticut Open-File Report 2005-1208 U.S. Department of the Interior U.S...Investigations to Support Nutrient- Related Water-Quality Improvements in the Thames River Basin, Connecticut 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM...Suggested Hydrologic Investigations to Support Nutrient- Related Water-Quality Improvements in the Thames River Basin, Connecticut By Elaine C. Todd
33 CFR 110.52 - Thames River, New London, Conn.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Thames River, New London, Conn. 110.52 Section 110.52 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY ANCHORAGES ANCHORAGE REGULATIONS Special Anchorage Areas § 110.52 Thames River, New London, Conn. (a) Area No...
33 CFR 110.52 - Thames River, New London, Conn.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Thames River, New London, Conn. 110.52 Section 110.52 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY ANCHORAGES ANCHORAGE REGULATIONS Special Anchorage Areas § 110.52 Thames River, New London, Conn. (a) Area No...
33 CFR 110.52 - Thames River, New London, Conn.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Thames River, New London, Conn. 110.52 Section 110.52 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY ANCHORAGES ANCHORAGE REGULATIONS Special Anchorage Areas § 110.52 Thames River, New London, Conn. (a) Area No...
33 CFR 110.52 - Thames River, New London, Conn.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Thames River, New London, Conn. 110.52 Section 110.52 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY ANCHORAGES ANCHORAGE REGULATIONS Special Anchorage Areas § 110.52 Thames River, New London, Conn. (a) Area No...
33 CFR 110.52 - Thames River, New London, Conn.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Thames River, New London, Conn. 110.52 Section 110.52 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY ANCHORAGES ANCHORAGE REGULATIONS Special Anchorage Areas § 110.52 Thames River, New London, Conn. (a) Area No...
33 CFR 334.75 - Thames River, Naval Submarine Base New London, restricted area.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Thames River, Naval Submarine....75 Thames River, Naval Submarine Base New London, restricted area. (a) The area: The open waters of... restricted area provided their vessels display registration numbers issued by the Naval Submarine Base, New...
33 CFR 334.75 - Thames River, Naval Submarine Base New London, restricted area.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 33 Navigation and Navigable Waters 3 2011-07-01 2011-07-01 false Thames River, Naval Submarine....75 Thames River, Naval Submarine Base New London, restricted area. (a) The area: The open waters of... restricted area provided their vessels display registration numbers issued by the Naval Submarine Base, New...
24. Looking east down Farnsworth Street to gate of Thames ...
24. Looking east down Farnsworth Street to gate of Thames Shipyard and the Thames River; Storage and Joiner Shop is large building in center; to right of that is Headhouse for Marine Railway #3; farther right is cradle of Marine Railway #3. - Thames Tow Boat Company, Foot of Farnsworth Street, New London, New London County, CT
Federal Register 2010, 2011, 2012, 2013, 2014
2012-11-13
... establishing a regulated navigation area (RNA) on the navigable waters of the Thames River in New London Harbor, New London, CT. The RNA will establish speed and wake restrictions and allow the Coast Guard to prohibit all vessel traffic through the RNA during degaussing range replacement operations, both planned...
Federal Register 2010, 2011, 2012, 2013, 2014
2012-09-05
... to establish a regulated navigation area (RNA) on the navigable waters of the Thames River in New London Harbor, New London, CT. The proposed RNA would establish speed and wake restrictions as well as allow the Coast Guard to prohibit all vessel traffic through the RNA during degaussing range replacement...
NASA Astrophysics Data System (ADS)
Whitehead, P. G.; Crossman, J.; Jin, L.
2011-12-01
The River Thames Catchment is the major water supply system in Southern England and supplies all of London's water supply from either the River Lee (a tributary of the Thames) or the main river abstraction site at Teddington (see Figure 1) or from groundwater sources in London. There has been a measurable change in rainfall patterns over the past 250 years with reducing summer rainfall and, hence flows, over the past 40 years. In 1976, following 3 dry winters, the London Reservoirs were more or less empty and the river flow direction was reversed to ensure a supply of water for London. Recent climate change studies in the Thames catchments suggest an increasing threat to water supply and also damage to river water quality and ecology. In addition to a changing climate, population levels in London have risen in recent years and the catchment is increasingly vulnerable to land use change. Since the 1920s changes in land use have increased the levels of nitrogen and phosphorus in the catchment and this trend is predicted to be exacerbated as climate change reduces freshwater dilution. Also land use is predicted to change as agriculture becomes more intensive as farmers react to higher grain and food prices. At the same time rising water temperatures has exposed the river to the potential for toxic algal blooms, such as cyanobacteria. This doom and gloom story is being managed however using a range of policy instruments, led by central government and public and private organisations such as Thames Water and the Environment Agency. Measures such as new reservoirs, a water transfer scheme from Wales and water metering to reduce demand are all being actively pursued, as are land management measures to control diffuse pollution. In order to assess the effects of climate change on the Thames catchment a major modelling study has been undertaken. The Integrated Catchment Model (INCA) has been set up for the Thames to model flow, nitrogen, phosphorus and ecology. Climate Change simulations predict reduced flow regimes in the river system and changes to the nitrogen patterns. Nitrate is predicted to reduce in summer, due to the lower flows which generate longer water residence times and hence allow more time for denitrification processes to occur. Phosphorus levels increase, however, due to the reduced dilution of effluents with subsequent detrimental effects on ecology. The model has been used to evaluate alternative water management policies such as a new reservoir for London, the transfer of water from the River Severn into the Thames, the reduction in P discharges from Sewage Treatment Works and the control of diffuse runoff by improved land management. Thus using the models to evaluate alternative strategies is very positive contribution to policy and planning.
Whitehead, P G; Crossman, J; Balana, B B; Futter, M N; Comber, S; Jin, L; Skuras, D; Wade, A J; Bowes, M J; Read, D S
2013-11-13
The catchment of the River Thames, the principal river system in southern England, provides the main water supply for London but is highly vulnerable to changes in climate, land use and population. The river is eutrophic with significant algal blooms with phosphorus assumed to be the primary chemical indicator of ecosystem health. In the Thames Basin, phosphorus is available from point sources such as wastewater treatment plants and from diffuse sources such as agriculture. In order to predict vulnerability to future change, the integrated catchments model for phosphorus (INCA-P) has been applied to the river basin and used to assess the cost-effectiveness of a range of mitigation and adaptation strategies. It is shown that scenarios of future climate and land-use change will exacerbate the water quality problems, but a range of mitigation measures can improve the situation. A cost-effectiveness study has been undertaken to compare the economic benefits of each mitigation measure and to assess the phosphorus reductions achieved. The most effective strategy is to reduce fertilizer use by 20% together with the treatment of effluent to a high standard. Such measures will reduce the instream phosphorus concentrations to close to the EU Water Framework Directive target for the Thames.
Modelling metaldehyde in catchments: a River Thames case-study.
Lu, Q; Whitehead, P G; Bussi, G; Futter, M N; Nizzetto, L
2017-04-19
The application of metaldehyde to agricultural catchment areas to control slugs and snails has caused severe problems for drinking water supply in recent years. In the River Thames catchment, metaldehyde has been detected at levels well above the EU and UK drinking water standards of 0.1 μg l -1 at many sites across the catchment between 2008 and 2015. Metaldehyde is applied in autumn and winter, leading to its increased concentrations in surface waters. It is shown that a process-based hydro-biogeochemical transport model (INCA-contaminants) can be used to simulate metaldehyde transport in catchments from areas of application to the aquatic environment. Simulations indicate that high concentrations in the river system are a direct consequence of excessive application rates. A simple application control strategy for metaldehyde in the Thames catchment based on model results is presented.
Wagley, Sariqa; Koofhethile, Kegakilwe; Rangdale, Rachel
2009-01-01
Chinese mitten crabs (Eriocheir sinensis) have been described as an alien invasive species in the River Thames, United Kingdom, and elsewhere in Europe. The crabs can cause considerable physical damage to the riverbeds and threaten native ecosystems. Trapping has been considered an option, but such attempts to control mitten crab populations in Germany in the 1930s failed. In the United Kingdom, it has been suggested that commercial exploitation of the species could be employed as a control option. This study was conducted as part of a larger program to assess the suitability of a commercial Chinese mitten crab fishery in the River Thames. Crabs and water samples from the River Thames between 2003 and 2006 were examined for the human pathogenic bacterium Vibrio parahaemolyticus. All samples throughout this testing period were positive for V. parahaemolyticus. The putative pathogenicity markers, thermostable direct hemolysin and thermostable direct-related hemolysin, were detected in one sample, indicating that the crabs possessed the potential to cause V. parahaemolyticus-associated illness if consumed without further processing. Levels of V. parahaemolyticus were higher during the summer than in the winter. This is the first study of V. parahaemolyticus prevalence in European-adapted Chinese mitten crabs.
Drainage divides, Massachusetts; Blackstone and Thames River basins
Krejmas, Bruce E.; Wandle, S. William
1982-01-01
Drainage boundaries for selected subbasins of the Blackstone and Thames River basins in eastern Hampden, eastern Hampshire, western Norfolk, southern Middlesex, and southern Worcester Counties, Massachusetts, are delineated on 12 topographic quadrangle maps at a scale of 1:24,000. Drainage basins are shown for all U.S. Geological Survey data-collection sites and for mouths of major rivers. Drainage basins are shown for the outlets of lakes or ponds and for streams where the drainage area is greater than 3 square miles. Successive sites along watercourses are indicated where the intervening area is at least 6 miles on tributary streams or 15 square miles along the Blackstone River, French River, or Quinebaug River. (USGS)
Long-term accumulation and transport of anthropogenic phosphorus in three river basins
NASA Astrophysics Data System (ADS)
Powers, Stephen M.; Bruulsema, Thomas W.; Burt, Tim P.; Chan, Neng Iong; Elser, James J.; Haygarth, Philip M.; Howden, Nicholas J. K.; Jarvie, Helen P.; Lyu, Yang; Peterson, Heidi M.; Sharpley, Andrew N.; Shen, Jianbo; Worrall, Fred; Zhang, Fusuo
2016-05-01
Global food production depends on phosphorus. Phosphorus is broadly applied as fertilizer, but excess phosphorus contributes to eutrophication of surface water bodies and coastal ecosystems. Here we present an analysis of phosphorus fluxes in three large river basins, including published data on fertilizer, harvested crops, sewage, food waste and river fluxes. Our analyses reveal that the magnitude of phosphorus accumulation has varied greatly over the past 30-70 years in mixed agricultural-urban landscapes of the Thames Basin, UK, the Yangtze Basin, China, and the rural Maumee Basin, USA. Fluxes of phosphorus in fertilizer, harvested crops, food waste and sewage dominate over the river fluxes. Since the late 1990s, net exports from the Thames and Maumee Basins have exceeded inputs, suggesting net mobilization of the phosphorus pool accumulated in earlier decades. In contrast, the Yangtze Basin has consistently accumulated phosphorus since 1980. Infrastructure modifications such as sewage treatment and dams may explain more recent declines in total phosphorus fluxes from the Thames and Yangtze Rivers. We conclude that human-dominated river basins may undergo a prolonged but finite accumulation phase when phosphorus inputs exceed agricultural demand, and this accumulated phosphorus may continue to mobilize long after inputs decline.
Bussi, Gianbattista; Whitehead, Paul G; Bowes, Michael J; Read, Daniel S; Prudhomme, Christel; Dadson, Simon J
2016-12-01
Potential increases of phytoplankton concentrations in river systems due to global warming and changing climate could pose a serious threat to the anthropogenic use of surface waters. Nevertheless, the extent of the effect of climatic alterations on phytoplankton concentrations in river systems has not yet been analysed in detail. In this study, we assess the impact of a change in precipitation and temperature on river phytoplankton concentration by means of a physically-based model. A scenario-neutral methodology has been employed to evaluate the effects of climate alterations on flow, phosphorus concentration and phytoplankton concentration of the River Thames (southern England). In particular, five groups of phytoplankton are considered, representing a range of size classes and pigment phenotypes, under three different land-use/land-management scenarios to assess their impact on phytoplankton population levels. The model results are evaluated within the framework of future climate projections, using the UK Climate Projections 09 (UKCP09) for the 2030s. The results of the model demonstrate that an increase in average phytoplankton concentration due to climate change is highly likely to occur, with the magnitude varying depending on the location along the River Thames. Cyanobacteria show significant increases under future climate change and land use change. An expansion of intensive agriculture accentuates the growth in phytoplankton, especially in the upper reaches of the River Thames. However, an optimal phosphorus removal mitigation strategy, which combines reduction of fertiliser application and phosphorus removal from wastewater, can help to reduce this increase in phytoplankton concentration, and in some cases, compensate for the effect of rising temperature. Copyright © 2016 Elsevier B.V. All rights reserved.
McGoran, A R; Clark, P F; Morritt, D
2017-01-01
Like many urban catchments, the River Thames in London is contaminated with plastics. This pollutant is recorded on the river banks, in the benthic environment and in the water column. The present study was conducted to assess the extent of microplastic ingestion in two River Thames fish species, the European flounder (Platichthys flesus) and European smelt (Osmerus eperlanus). Samples were collected from two sites in Kent, England; Erith and Isle of Grain/Sheppey, near Sheerness, with the latter being more estuarine. The results revealed that up to 75% of sampled European flounder had plastic fibres in the gut compared with only 20% of smelt. This difference may be related to their diverse feeding behaviours: European flounder are benthic feeders whilst European smelt are pelagic predators. The fibres were predominantly red or black polyamides and other fibres included acrylic, nylon, polyethylene and polyethylene terephthalate and there was no difference in occurrence between the sites sampled. Copyright © 2016 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Mackay, Jonathan; Abesser, Corinna; Hughes, Andrew; Jackson, Chris; Kingdon, Andrew; Mansour, Majdi; Pachocka, Magdalena; Wang, Lei; Williams, Ann
2013-04-01
The River Thames catchment is situated in the south-east of England. It covers approximately 16,000 km2 and is the most heavily populated river basin in the UK. It is also one of the driest and has experienced severe drought events in the recent past. With the onset of climate change and human exploitation of our environment, there are now serious concerns over the sustainability of water resources in this basin with 6 million m3 consumed every day for public water supply alone. Groundwater in the Thames basin is extremely important, providing 40% of water for public supply. The principal aquifer is the Chalk, a dual permeability limestone, which has been extensively studied to understand its hydraulic properties. The fractured Jurassic limestone in the upper catchment also forms an important aquifer, supporting baseflow downstream during periods of drought. These aquifers are unconnected other than through the River Thames and its tributaries, which provide two-thirds of London's drinking water. Therefore, to manage these water resources sustainably and to make robust projections into the future, surface and groundwater processes must be considered in combination. This necessitates the simulation of the feedbacks and complex interactions between different parts of the water cycle, and the development of integrated environmental models. The Open Modelling Interface (OpenMI) standard provides a method through which environmental models of varying complexity and structure can be linked, allowing them to run simultaneously and exchange data at each timestep. This architecture has allowed us to represent the surface and subsurface flow processes within the Thames basin at an appropriate level of complexity based on our understanding of particular hydrological processes and features. We have developed a hydrological model in OpenMI which integrates a process-driven, gridded finite difference groundwater model of the Chalk with a more simplistic, semi-distributed conceptual model of the Jurassic limestone. A distributed river routing model of the Thames has also been integrated to connect the surface and subsurface hydrological processes. This application demonstrates the potential benefits and issues associated with implementing this approach.
NASA Astrophysics Data System (ADS)
Noacco, V.; Howden, N. J. K.; Wagener, T.; Worrall, F.; Burt, T. P.
2015-12-01
This study investigates drivers of changing dissolved organic carbon (DOC) export in the UK's River Thames basin between 1884 and 2014. Specifically, we consider how the impacts of land-use change and population growth drive increases in DOC concentrations and fluxes at the basin outlet. Such key factors for the long-term increase in riverine DOC in temperate, mineral-soil catchments are still widely debated. First, we estimate soil organic carbon (SOC) stocks in the Thames basin for the period. Second, we convert SOC losses due to land-use change into DOC loss to surface waters through runoff. Finally, we combine this input of DOC with an export coefficient model that considers catchment drivers for DOC release to the river. SOC stocks for each year are calculated from a large database of typical SOC levels for land-uses present in the Thames basin and are combined with literature values of transition times for SOC to adjust to a new level following land-use change. We also account for climate change effects on SOC stock due to temperature increases, which reduces SOC stocks as soil organic matter turnover rates increase. Our work shows that the major driver for DOC increase to the river Thames was the rise in the catchment population, where the increase in urban area was used as a proxy. This highlights the role of sewage effluent in contributing to the rise of fluvial DOC, even though wastewater treatments were in place since the early 1990s. Land-use change had significant but short-term impacts in the increase in DOC, mainly due to massive conversion of permanent grassland into arable land during World War II.
Bowes, M J; Loewenthal, M; Read, D S; Hutchins, M G; Prudhomme, C; Armstrong, L K; Harman, S A; Wickham, H D; Gozzard, E; Carvalho, L
2016-11-01
River phytoplankton blooms can pose a serious risk to water quality and the structure and function of aquatic ecosystems. Developing a greater understanding of the physical and chemical controls on the timing, magnitude and duration of blooms is essential for the effective management of phytoplankton development. Five years of weekly water quality monitoring data along the River Thames, southern England were combined with hourly chlorophyll concentration (a proxy for phytoplankton biomass), flow, temperature and daily sunlight data from the mid-Thames. Weekly chlorophyll data was of insufficient temporal resolution to identify the causes of short term variations in phytoplankton biomass. However, hourly chlorophyll data enabled identification of thresholds in water temperature (between 9 and 19°C) and flow (<30m(3)s(-1)) that explained the development of phytoplankton populations. Analysis showed that periods of high phytoplankton biomass and growth rate only occurred when these flow and temperature conditions were within these thresholds, and coincided with periods of long sunshine duration, indicating multiple stressor controls. Nutrient concentrations appeared to have no impact on the timing or magnitude of phytoplankton bloom development, but severe depletion of dissolved phosphorus and silicon during periods of high phytoplankton biomass may have contributed to some bloom collapses through nutrient limitation. This study indicates that for nutrient enriched rivers such as the Thames, manipulating residence time (through removing impoundments) and light/temperature (by increasing riparian tree shading) may offer more realistic solutions than reducing phosphorus concentrations for controlling excessive phytoplankton biomass. Crown Copyright © 2016. Published by Elsevier B.V. All rights reserved.
1979-09-01
of slm~ lu THAMES RIVER BASIN 00 DUDLEY, MASSACHUSETTS 0 0 in MERINO POND DAM MA 00110 0 PHASE I INSPECTION REPORT 0 NATIONAL DAM INSPECTION PROGRAM ...NATIONAL PROGRAM FOR INSPECTION OF NON-FEDERAL , e, .* f. ,,,-Ue I,. h TNw@ e 6, CONTACT OR IAUNT ONUWSaEPe* U.S. AMY CORPS OF ENGINEERS NEW ENGLAND...SAaUmN el ame 6 am vel NSON* Odlmwmn ba 00-0 o6. oll.I,,NIA*v mOTE& Cover program reads: Phase I Inspection Report, National Dam Inspection Program
Dynamic modelling of five different phytoplankton groups in the River Thames (UK)
NASA Astrophysics Data System (ADS)
Bussi, Gianbattista; Whitehead, Paul; Bowes, Michael; Read, Daniel; Dadson, Simon
2015-04-01
Phytoplankton play a vital role in fluvial ecosystems, being a major producer of organic carbon, a food source for primary consumers and a relevant source of oxygen for many low-gradient rivers, but also a producer of potentially harmful toxins (e.g. cyanobacteria). For these reasons, the forecast and prevention of algal blooms is fundamental for the safe management of river systems. In this study, we developed a new process-based phytoplankton model for operational management and forecast of algal and cyanobacteria blooms subject to environmental change. The model is based on a mass-balance and it reproduces phytoplankton growth and death, taking into account the controlling effect played by water temperature, solar radiation, self-shading and dissolved phosphorus and silicon concentrations. The model was implemented in five reaches of the River Thames (UK) with a daily time step over a period of three years, and its results were compared to a novel dataset of cytometric data which includes community cell abundance of chlorophytes, diatoms, cyanobacteria, microcystis-like cyanobacteria and picoalgae. The model results were satisfactory in terms of fitting the observed data. A Multi-Objective General Sensitivity Analysis was also carried out in order to quantify model sensitivity to its parameters. It showed that the most influential parameters are phytoplankton growth and death rates, while phosphorus concentration showed little influence on phytoplankton growth, due to the high levels of phosphorus in the River Thames. The model was demonstrated to be a reliable tool to be used in algal bloom forecasting and management.
NASA Astrophysics Data System (ADS)
Bussi, Gianbattista; Whitehead, Paul; Dadson, Simon
2016-04-01
In this study, we assess the impact of changes in precipitation and temperature on the phytoplankton concentration of the River Thames (UK) by means of a physically-based model. A scenario-neutral approach was employed to evaluate the effects of climate variability on flow, phosphorus concentration and phytoplankton concentration. In particular, the impact of uniform changes in precipitation and temperature on five groups of phytoplankton (diatoms and large chlorophytes, other chlorophytes, picoalgae, Microcystis-like cyanobacteria and other cyanobacteria) was assessed under three different land-use/land-management scenarios (1 - current land use and phosphorus reduction practices; 2 - expansion of agricultural land and current phosphorus reduction practices; 3 - expansion of agricultural land and optimal phosphorus reduction practices). The model results were assessed within the framework of future climate projections, using the UK Climate Projections 09 (UKCP09) for the 2030s. The results of the model demonstrate that an increase in average phytoplankton concentration due to climate change is highly likely to occur, and its magnitude varies depending on the river reach. Cyanobacteria show significant increases under future climate change and land-use change. An expansion of intensive agriculture accentuates the growth in phytoplankton, especially in the upper reaches of the River Thames. However, an optimal phosphorus removal mitigation strategy, which combines reduction of fertiliser application and phosphorus removal from wastewater, can help to reduce this increase in phytoplankton concentration, and in some cases, compensate for the effect of rising temperature.
Effect of dredge spoil deposition on fecal coliform counts in sediments at a disposal site.
Babinchak, J A; Graikoski, J T; Dudley, S; Nitkowski, M F
1977-01-01
The most-probable-number of fecal coliforms in sediments was monitored at the New London dump site in Long Island Sound during the deposition of dredge spoil from the Thames River. Although the geometric mean for fecal coliforms at five stations in the river was 14,000/100 ml before dredging commenced, the deposition of this material did not increase the incidence of fecal coliforms at 17 spoil stations and 13 control stations in the disposal and surrounding areas. Fecal coliforms appear to occur only in the surface sediment material and are diluted by the subsurface material during the dredging operation. Fecal coliform analyses of bottom waters during high and low tides indicated that the flow of water from the Thames River played a major role in determining the most-probable-number of fecal coliforms in the sediments at the disposal site. PMID:329761
U.K. Flooding Captured by NASA Spacecraft
2014-02-19
This image acquired by NASA Terra spacecraft depicts the high water levels and flooding along the Thames River west of London as record-breaking rains covered the United Kingdom in January and February.
Data-Logging--A Plug-and-Play Oxygen Probe?
ERIC Educational Resources Information Center
Warne, Peter
1997-01-01
Presents an experiment on collecting data while measuring the dissolved-oxygen levels in Thames River tap water straight from the water mains and dissolved-oxygen levels in rainwater containing Hornwort water weed over 24 hours. (Author/ASK)
7. VIEW SOUTHEAST, SHOWING WEST SIDE FROM LAND, WITH WASTE ...
7. VIEW SOUTHEAST, SHOWING WEST SIDE FROM LAND, WITH WASTE PAPER BUNDLED ON DOCK, AWAITING LOADING ONTO ODIGITRIA B - Connecticut State Pier, State Pier Road at Thames River, New London, New London County, CT
Plastic in the Thames: a river runs through it.
Morritt, David; Stefanoudis, Paris V; Pearce, Dave; Crimmen, Oliver A; Clark, Paul F
2014-01-15
Although contamination of the marine ecosystems by plastics is becoming recognised as a serious pollution problem, there are few studies that demonstrate the contribution made by freshwater catchments. Over a three month period from September to December 2012, at seven localities in the upper Thames estuary, 8490 submerged plastic items were intercepted in eel fyke nets anchored to the river bed. Whilst there were significant differences in the numbers of items at these locations, the majority were some type of plastic. Additionally in excess of 20% of the litter items were components of sanitary products. The most contaminated sites were in the vicinity of sewage treatment works. While floating litter is visible, this study also demonstrates that a large unseen volume of submerged plastic is flowing into the marine environment. It is therefore important that this sub-surface component is considered when assessing plastic pollution input into the sea. Copyright © 2013 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Worrall, F.; Howden, N. J. K.; Burt, T. P.
2012-10-01
SummaryThis paper analyses the world's longest fluvial record of water hardness and calcium (Ca) concentration. We used records of permanent and temporary hardness and river flow for the UK's River Thames (catchment area 9998 km2) to estimate annual Ca flux from the river since 1883. The Thames catchment has a mix of agricultural and urban land use; it is dominated by mineral soils with groundwater contributing around 60% of river flow. Since the late 1800s, the catchment has undergone widespread urbanisation and climate warming, but has also been subjected to large-scale land-use change, especially during World War II and agricultural intensification in the 1960s. Here, we use a range of time series methods to explore the relative importance of these drivers in determining catchment-scale biogeochemical response. Ca concentrations in the Thames rose to a peak in the late 1980s (106 mg Ca/l). The flux of Ca peaked in 1916 at 385 ktonnes Ca/yr; the minimum was in 1888 at 34 ktonnes Ca/yr. For both the annual average Ca concentration and the annual flux of Ca, there were significant increases with time; a significant positive memory effect relative to the previous year; and significant correlation with annual water yield. No significant correlation was found with either temperature or land use, but sulphate deposition was found to be significant. It was also possible, for a shorter time series, to show a significant relationship with inorganic nitrogen inputs into the catchment. We suggest that ionic inputs did not acidify the mineral soils of the catchment but did cause the leaching of metals, so we conclude that the decline in river Ca concentrations is caused by the decline in both S and N inputs.
33 CFR 100.101 - Harvard-Yale Regatta, Thames River, New London, CT.
Code of Federal Regulations, 2010 CFR
2010-07-01
... race course, between Scotch Cap and Bartlett Point Light. (ii) Within the race course boundaries or in... not cause waves which result in damage to submarines or other vessels in the floating drydocks. (11...
1983-12-01
ENGINEERS WALTHAM MR NEWl INLSIID2GSRDDVDEC 83 F/G 13/2 U mEEmhhhohhhmhI MIRO OP RE OAV IS H R L -I- I~JDrought Contingency US Army Corps of Engineers Plan...LA.KE WA’ N, t:ehauc River, 3c,,thhr:Aee ino t irhrid. Massacnusetts -RAIN.A\\, ; AREA 4Q. quare miles ;ro-s’ 322 . saire miles ,net’ sT,’k.,; "’:Es 7lood
Whitehead, P G; Leckie, H; Rankinen, K; Butterfield, D; Futter, M N; Bussi, G
2016-12-01
Pathogens are an ongoing issue for catchment water management and quantifying their transport, loss and potential impacts at key locations, such as water abstractions for public supply and bathing sites, is an important aspect of catchment and coastal management. The Integrated Catchment Model (INCA) has been adapted to model the sources and sinks of pathogens and to capture the dominant dynamics and processes controlling pathogens in catchments. The model simulates the stores of pathogens in soils, sediments, rivers and groundwaters and can account for diffuse inputs of pathogens from agriculture, urban areas or atmospheric deposition. The model also allows for point source discharges from intensive livestock units or from sewage treatment works or any industrial input to river systems. Model equations are presented and the new pathogens model has been applied to the River Thames in order to assess total coliform (TC) responses under current and projected future land use. A Monte Carlo sensitivity analysis indicates that the input coliform estimates from agricultural sources and decay rates are the crucial parameters controlling pathogen behaviour. Whilst there are a number of uncertainties associated with the model that should be accounted for, INCA-Pathogens potentially provides a useful tool to inform policy decisions and manage pathogen loading in river systems. Copyright © 2016. Published by Elsevier B.V.
NASA Astrophysics Data System (ADS)
Bussi, Gianbattista; Dadson, Simon J.; Prudhomme, Christel; Whitehead, Paul G.
2016-11-01
The effects of climate change and variability on river flows have been widely studied. However the impacts of such changes on sediment transport have received comparatively little attention. In part this is because modelling sediment production and transport processes introduces additional uncertainty, but it also results from the fact that, alongside the climate change signal, there have been and are projected to be significant changes in land cover which strongly affect sediment-related processes. Here we assess the impact of a range of climatic variations and land covers on the River Thames catchment (UK). We first calculate a response of the system to climatic stressors (average precipitation, average temperature and increase in extreme precipitation) and land-cover stressors (change in the extent of arable land). To do this we use an ensemble of INCA hydrological and sediment behavioural models. The resulting system response, which reveals the nature of interactions between the driving factors, is then compared with climate projections originating from the UKCP09 assessment (UK Climate Projections 2009) to evaluate the likelihood of the range of projected outcomes. The results show that climate and land cover each exert an individual control on sediment transport. Their effects vary depending on the land use and on the level of projected climate change. The suspended sediment yield of the River Thames in its lowermost reach is expected to change by -4% (-16% to +13%, confidence interval, p = 0.95) under the A1FI emission scenario for the 2030s, although these figures could be substantially altered by an increase in extreme precipitation, which could raise the suspended sediment yield up to an additional +10%. A 70% increase in the extension of the arable land is projected to increase sediment yield by around 12% in the lowland reaches. A 50% reduction is projected to decrease sediment yield by around 13%.
Earth Observations taken by the Expedition 10 crew
2005-04-02
ISS010-E-22495 (2 April 2005) --- Numerous recognizable features appear in this detailed view of London, United Kingdom, photographed by an Expedition 10 crewmember on the International Space Station (ISS). The photographer had to look back along track for the shot, from a position over northern Germany. The most striking visual features are green open spaces such as Regents Park, Hyde Park and St. Jamess Park east of Buckingham Palace. Many smaller parks indicate why Londoners are proud of being able to walk miles through the city mainly on grass. The River Thameswith its bridges and barges (some of the more than 14,000 craft registered to sail the Thames)is the axis upon which the city was founded in Roman times. The relatively small area known as the City of London coincides with the ancient walled Roman city of Londinium on the north bank of the river (the line of the wall is marked closely for almost its entire length by modern streets), and includes St. Pauls Cathedral near where the Roman temple stood. For scale, the river is 265 meters wide near St. Pauls. The City is the financial center while Westminster is the center of government, including the Houses of Parliament and Downing Street, where the British Prime Minister lives. Several large structures visible in this image are railroad stations; three serving areas north of London (Euston, St. Pancras and Kings Cross), and Waterloo Station serving southern Britain. The London Eye, a famous Ferris wheel 140 meters high, is situated on an oval island in the River Thames, visible just west of Waterloo Station. Many larger buildings can also be identified, partly because they cast shadowsBuckingham Palace, St Pauls Cathedral, and the Tate Modern art museum (a converted power station, the 99-meter chimney was designed to fall just short of the crest of St Pauls dome).
Horton, Alice A; Svendsen, Claus; Williams, Richard J; Spurgeon, David J; Lahive, Elma
2017-01-15
Sewage effluent input and population were chosen as predictors of microplastic presence in sediments at four sites in the River Thames basin (UK). Large microplastic particles (1mm-4mm) were extracted using a stepwise approach to include visual extraction, flotation and identification using Raman spectroscopy. Microplastics were found at all four sites. One site had significantly higher numbers of microplastics than other sites, average 66 particles 100g -1 , 91% of which were fragments. This site was downstream of a storm drain outfall receiving urban runoff; many of the fragments at this site were determined to be derived of thermoplastic road-surface marking paints. At the remaining three sites, fibres were the dominant particle type. The most common polymers identified included polypropylene, polyester and polyarylsulphone. This study describes two major new findings: presence of microplastic particles in a UK freshwater system and identification of road marking paints as a source of microplastics. This study is the first to quantify microplastics of any size in river sediments in the UK and links their presence to terrestrial sources including sewage and road marking paints. Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Theofanidi, Sofia; Cloke, Hannah Louise; Clark, Joanna
2017-04-01
Floods are a global threat to social, economic and environmental development and there is a likelihood, that they could occur more frequently in the future due to climatic change. The severity of their impacts, which can last for years, has led to the urgent need for local communities and national authorities to develop flood warning systems for a better flood preparedness and emergency response. The flood warning systems often rely on hydrological forecasting tools to predict the hydrological response of a watershed before or during a flood event. Hydrological models have been substantially upgraded since the first use of hydrographs and the use of simple conceptual models. Hydrodynamic and hydraulic routing enables the spatial and temporal prediction of flow rates (peak discharges) and water levels. Moreover, the hydrodynamic modeling in 2D permits the estimation of the flood inundation area. This can be particularly useful because the flood zones can provide essential information about the flood risk and the flood damage. In this study, we use a hydrodynamic model which can simulate water levels and river flows in open channel conditions. The model can incorporate the effect of several river structures in the flood modeling process, such as the existence of bridges and weirs. The flood routing method is based on the solution of continuity and energy momentum equations. In addition, the floodplain inundation modeling which is based on the solution of shallow water equations along the channel's banks, will be used for the mapping of flood extent. A GIS interface will serve as a database, including high resolution topography, vector layers of river network, gauging stations, land use and land cover, geology and soil information. The flood frequency analysis, together with historical records on flood warnings, will enable the understanding on the flow regimes and the selection of particular flood events for modeling. One dimensional and two dimensional simulations of the flood events will follow, using simple hydrological boundary conditions. The sensitivity testing of the model, will permit to assess which parameters have the potential to alter significantly the peak discharge during the flood, flood water levels and flood inundation extent. Assessing the model's sensitivity and uncertainty, contributes to the improvement of the flood risk knowledge. The area of study is a subcatchment of the River Thames in the southern part of the United Kingdom. The Thames with its tributaries, support a wide range of social, economic and recreational activities. In addition, the historical and environmental importance of the Thames valley highlights the need for a sustainable flood mitigation planning which includes the better understanding of the flood mechanisms and flood risks.
Persistent Organic Pollutants in sediment and fish in the River Thames Catchment (UK).
Lu, Qiong; Jürgens, Monika D; Johnson, Andrew C; Graf, Carola; Sweetman, Andy; Crosse, John; Whitehead, Paul
2017-01-15
Some organic pollutants including polychlorinated biphenyls (PCBs), polybrominated diphenylethers (PBDEs) and hexachlorobenzene (HCB) have been banned from production and use in the UK for >30years but due to their toxicity and persistence are still of concern. However, due to their hydrophobicity they are present at very low concentrations and are difficult to measure in water, and so other matrices need to be sampled in order to best assess contamination. This study measured concentrations of ΣICES 7 PCBs (PCB congeners 28, 52, 101, 118, 138, 153 and 180) and Σ6 PBDEs (PBDE congeners 28, 47, 99, 100, 153, 154) and HCB in both bed-sediments and wild roach (a common pelagic fish) in the Thames Basin. The highest sediment concentrations were detected in an urbanised tributary of the Thames, The Cut at Bracknell (HCB: 0.03-0.40μg/kg dw; ICES 7 PCBs: 4.83-7.42μg/kg dw; 6 BDEs: 5.82-23.10μg/kg dw). When concentrations were expressed on a dry weight basis, the fish were much more contaminated than the sediments, but when sediment concentrations were normalised to organic carbon concentration they were comparable to the fish lipid normalised concentrations. Thus, despite the variability in the system, both sediments and wild fish can be considered suitable for representing the level of POPs contamination of the river system given sufficient sample numbers. Copyright © 2016 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Powers, S. M.; Burt, T. P.; Chan, N. I.; Elser, J. J.; Haygarth, P. M.; Howden, N. J. K.; Jarvie, H. P.; Peterson, H. M.; Shen, J.; Worrall, F.; Sharpley, A. N.
2014-12-01
Phosphorus (P) is closely linked to major societal concerns including food security and water quality, and human activities strongly control the modern global P cycle. Current knowledge of the P cycle includes many insights about relatively short-term processes, but a long-term and landscape-level view may be needed to understand P status and optimize P management towards P sustainability. We reconstructed long-term (>40 years) P mass balances and rates of P accumulation in three major river basins where excess P pollution is demanding improvements in P management at local, national, and international levels. We focus on: Maumee River Basin, a major source of agricultural P to Lake Erie, the southernmost and shallowest of the Laurentian Great Lakes; Thames River Basin, where fluxes of effluent P from the London, England metropolitan area have declined following improvements in wastewater treatment; Yangtze (Changjiang) River Basin, the largest in China, which is undergoing rapid economic development. The Maumee and Thames are intensively monitored, and show long-term declines in basin P inputs that represent a step towards P sustainability. However, river P outputs have been slower to decline, consistent with the hypothesis that legacy P is mobilizing from soils or from within the river network. Published data on the Yangtze indicate the P flux from land to water has clearly increased with industrialization and population growth. Historical trajectories of P accumulation and depletion in major river basins are providing new understanding about the long-term impacts of P management, including watershed P legacies and response times, that may inform future policy towards local, national, and global P sustainability.
NASA Astrophysics Data System (ADS)
Miller, J. D.; Rickards, N. J.; Kjeldsen, T. R.; Hutchins, M.; Rowland, C.; Prudhomme, C.; Maliko, T.; Fidal, J.; Hagen-Zanker, A.
2016-12-01
The UK population is set to increase by 16% by 2035; it is therefore increasingly important to understand the impact this may have on urban populations, and in turn how this will affect river flow regimes and water quality in urban areas. A growing population is likely to lead to an increase in urban land use and impervious surfaces, the implications of which are not yet fully understood for issues such as future flood risk. The aim of this paper is to develop a greater understanding of the impacts of both an increasing population and urban extent in the context of a changing climate, and to assess the effect these may have on urban streamflow regimes and water security in the future. Flows are modelled for selected catchments in the Thames basin using URBMOD, a lumped rainfall runoff model that is able to represent both pervious and impervious surfaces, reducing infiltration in catchments where there is a greater urban extent. The model uses daily catchment average rainfall and evapotranspiration derived from gridded data, and is calibrated against long-term river flow records. Historic satellite imagery is used to train cellular automata land use models, which are then applied under different scenarios of urban development up to 2035. These changes in land use are combined with a range of climate change scenarios to give an indication of how urban flow regimes may be altered in the Thames basin over the next 20 years. Results suggest an intensification of the hydrological regime in the majority of catchments, with increases in high flow magnitudes (Q10) of up to 5%. The trend for low flows (Q90) is less clear, with some catchments displaying reductions of around 4%, whilst others show slight increased flows. We identify the main drivers behind these changes, from which the fine-scale impacts of urbanisation on water resources can be better understood. Research findings are being used to inform a regional-scale model, coupling water quantity and quality and providing insight to urban planners and stakeholders on the future urban hydrological regime in the Thames basin. Similar approaches are being used to assess impacts of anthropogenic drivers on water resources in the Cauvery basin in India, whereby the applicability of the model under very different climate and urban morphology will be tested.
Sediment Spews from Connecticut River
2017-12-08
NASA image acquired September 2, 2011 To download the full high res go to: earthobservatory.nasa.gov/IOTD/view.php?id=52059 Nearly a week after Hurricane Irene drenched New England with rainfall in late August 2011, the Connecticut River was spewing muddy sediment into Long Island Sound and wrecking the region's farmland just before harvest. The Thematic Mapper on the Landsat 5 satellite acquired this true-color satellite image on September 2, 2011. With its headwaters near the Canadian border, the Connecticut River drains nearly 11,000 square miles (28,500 square kilometers) and receives water from at least 33 tributaries in Vermont, New Hampshire, Massachusetts, and Connecticut. The 410-mile river—New England's longest—enters Long Island Sound near Old Lyme, Connecticut, and is estimated to provide 70 percent of the fresh water entering the Sound. When Irene blew through the region on August 27-28, substantial portions of the Connecticut River watershed received more than 6 to 8 inches (15-20 centimeters) of rainfall, and several locations received more than 10 inches (25 centimeters). Whole towns were cut off from overland transportation—particularly upstream in Vermont, which suffered its worst flooding in 80 years. Thousands of people saw their homes flooded, if not washed off their foundations, at a time of year when rivers are usually at their lowest. Preliminary estimates of river flow at Thompsonville, Connecticut, (not shown in this image) reached 128,000 cubic feet per second (cfs) on August 30, nearly 64 times the usual flow (2,000 cfs) for early fall and the highest flow rate since May 1984. At the mouth of the river—where flow is tidal, and therefore not gauged—the peak water height reached 6.9 feet (2.1 meters) above sea level, almost a foot higher than at any time in the past 10 years. According to Suzanne O'Connell, an environmental scientist working along the Connecticut River at Wesleyan University, the torrent of water coursing through New England picked up silt and clay from the river valleys, giving it the tan color shown in the image above. At Essex, Connecticut, the turbidity (muddiness) of the water was 50 times higher than pre-Irene values. To the east, the Thames River appears to be carrying very little sediment at all on September 2. According to O'Connell, the Thames "drains glaciated terrain, so fine sediment was removed long ago." Most of the land surface in the Thames basin is "just bedrock, till, and glacial erratics." Unlike the Connecticut, areas within the Thames watershed only received 2 to 4 inches of rain in most locations. The flooding that occurred in the aftermath of Hurricane Irene inundated farmland in Massachusetts and Connecticut just before harvest time, the Associated Press noted. Crops were drowned under inches to feet of water. The substantial amounts of soil, sediment, and water deposited on land during the flood could also pose trouble for farmers in coming seasons. "It's notable that whole segments of river bank are just gone," said Andrew Fisk of the Connecticut River Watershed Council. "That's not just loss of sediment. That's land disappearing down river." NASA Earth Observatory image by Robert Simmon, using Landsat 5 data from the U.S. Geological Survey Global Visualization Viewer. Caption by Michael Carlowicz, with interpretation help from Suzanne O'Connell, Wesleyan University, and Andrew Fisk, Connecticut River Watershed Council. Instrument: Landsat 5 - TM Credit: NASA Earth Observatory NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram
Rowney, Nicole C; Johnson, Andrew C; Williams, Richard J
2009-12-01
Cytotoxic, also known as antineoplastic, drugs remain an important weapon in the fight against cancer. This study considers the water quality implications for the Thames catchment (United Kingdom) arising from the routine discharge of these drugs after use, down the drain and into the river. The review focuses on 13 different cytotoxic drugs from the alkylating agent, antimetabolite, and anthracycline antibiotic families. A geographic-information-system-based water quality model was used in the present study. The model was informed by literature values on consumption, excretion, and fate data to predict raw drinking water concentrations at the River Thames abstraction points at Farmoor, near Oxford, and Walton, in West London. To discover the highest plausible values, upper boundary values for consumption and excretion together with lower removal values for sewage treatment were used. The raw drinking water cytotoxic drug maximum concentrations at Walton (the higher of the two) representative of mean and low flow conditions were predicted to be 11 and 20 ng/L for the five combined alkylating agents, 2 and 4 ng/L for the three combined antimetabolites, and 0.05 and 0.10 ng/L the for two combined anthracycline antibiotics, respectively. If they were to escape into tap water, then the highest predicted concentrations would still be a factor of between 25 and 40 below the current recommended daily doses of concern. Although the risks may be negligible for healthy adults, more concern may be associated with special subgroup populations, such as pregnant women, their fetuses, and breast-feeding infants, due to their developmental vulnerability.
Hydrochemical processes in lowland rivers: insights from in situ, high-resolution monitoring
NASA Astrophysics Data System (ADS)
Wade, A. J.; Palmer-Felgate, E. J.; Halliday, S. J.; Skeffington, R. A.; Loewenthal, M.; Jarvie, H. P.; Bowes, M. J.; Greenway, G. M.; Haswell, S. J.; Bell, I. M.; Joly, E.; Fallatah, A.; Neal, C.; Williams, R. J.; Gozzard, E.; Newman, J. R.
2012-11-01
This paper introduces new insights into the hydrochemical functioning of lowland river systems using field-based spectrophotometric and electrode technologies. The streamwater concentrations of nitrogen species and phosphorus fractions were measured at hourly intervals on a continuous basis at two contrasting sites on tributaries of the River Thames - one draining a rural catchment, the River Enborne, and one draining a more urban system, The Cut. The measurements complement those from an existing network of multi-parameter water quality sondes maintained across the Thames catchment and weekly monitoring based on grab samples. The results of the sub-daily monitoring show that streamwater phosphorus concentrations display highly complex dynamics under storm conditions dependent on the antecedent catchment wetness, and that diurnal phosphorus and nitrogen cycles occur under low flow conditions. The diurnal patterns highlight the dominance of sewage inputs in controlling the streamwater phosphorus and nitrogen concentrations at low flows, even at a distance of 7 km from the nearest sewage treatment works in the rural River Enborne. The time of sample collection is important when judging water quality against ecological thresholds or standards. An exhaustion of the supply of phosphorus from diffuse and multiple septic tank sources during storm events was evident and load estimation was not improved by sub-daily monitoring beyond that achieved by daily sampling because of the eventual reduction in the phosphorus mass entering the stream during events. The results highlight the utility of sub-daily water quality measurements and the discussion considers the practicalities and challenges of in situ, sub-daily monitoring.
Carbon, nitrogen, and phosphorus stoichiometry and eutrophication in River Thames Tributaries, UK
USDA-ARS?s Scientific Manuscript database
Primary productivity in aquatic systems relies on the availability of carbon (C), nitrogen (N) and phosphorus (P), with a preferred stoichiometric ratio of 106 C/16 N/1 P, known as the Redfield ratio. The intent of this paper is to present a methodology to visualize C/N/P stoichiometry and examine ...
Federal Register 2010, 2011, 2012, 2013, 2014
2012-06-08
..., Operation Sail, Inc., is planning to publish information on the event in local newspapers, internet sites... areas for viewing the ``Parade of Sail'' have been established to allow for maximum use of the waterways... sponsoring organization, Operation Sail, Inc., is planning to publish information of the event in local...
NASA Astrophysics Data System (ADS)
Miller, J.; Hutchins, M.; McGrane, S. J.; Kjeldsen, T. R.; Rowland, C.; Hagen-Zanker, A.; Rickards, N. J.; Fidal, J.; Vesuviano, G.; Hitt, O.
2016-12-01
Rapid urbanisation coupled with climate change poses a significant threat of increased flooding in urban locations around the world. In the UK there is a lack of joined up science and monitoring data to support model development and management decisions required for a rapidly growing population. Here, we present the findings from a multi-disciplinary research project entitled POLLCURB involving a combination of both monitoring and modelling approaches, including participatory citizen science, to evaluate impacts of urbanisation and climate change on flooding and water quality in the Thames basin, United Kingdom. Empirical analysis of five years of monitoring data in intensely monitored sub-catchments reveals the degree to which urban land-use impacts upon hydrological and water quality response. Analysis reveals hydrological impacts do not always follow the expected urban gradient due to intra-catchment differences in hydraulic functions. Statistical detection and attribution techniques are used to assess long-term river data, highlighting strong signals of urban growth after climate variability is accounted for. Historical land-use change mapping of the Thames basin using remote sensing shows growth in urban coverage from around 13% (1980's) to 15% (2015) and was used to develop and train a cellular automata model. Projections of a business-as-usual scenario indicates future growth of 12% by 2035. Future potential changes to flooding and water quality are assessed under urbanisation and climate scenarios for the Thames region to provide comparative and cumulative analysis of how these drivers will affect existing and new urban areas within the Thames basin. Results show the relative and cumulative impacts that both urbanisation and climate change have on basin hydrology and water quality, and highlight the improvements in modelling accuracy when utilising high-resolution data. Discussion is made of results in relation to modelling, policy, mitigation options, and implications for further scientific research.
1978-10-01
GRA&I UnTucea B WILLIAMS POND DAM ~~1Z~ CT 00551 _ Distribution/ Availabilit Y Codes Avail and/or Dis~tj pecialS RIVER BASIN ~lIILEBANON, COXNNECTICUT...Inspection Report. Alternatives to these recommendations r 1 would include reducing the Williams Pond water levels during expected periods of intense storm...Materials Branch Engi’neering Division FRED J. VNS. Jr., Member Chief, De ’ggn Branch Engineering Division SAUL COOPER, -r Chief, Water Control Branch
7. Photographic copy of color photograph of NUWC from the ...
7. Photographic copy of color photograph of NUWC from the Thames River, 1988, view northwest. Original color negative no. N0211-SP-88(L)-02389.16 on file at photo lab at NUWC, Newport, R.I. Copyright-free. - Naval Undersea Warfare Center, East side of Smith & East Streets between Columbia & South Coves, New London, New London County, CT
8. Photographic copy of color photograph of NUWC from the ...
8. Photographic copy of color photograph of NUWC from the Thames River, 1988, view southeast. Original color negative no. N0211-SP-88(L)-02389.4 on file at photo lab at NUWC, Newport, R.I. Copyright-free. - Naval Undersea Warfare Center, East side of Smith & East Streets between Columbia & South Coves, New London, New London County, CT
Federal Register 2010, 2011, 2012, 2013, 2014
2012-03-19
... Sail'' a tall ship marine parade into New London Harbor. Tall ships and other participating vessels will be staged in Niantic Bay on July 6, 2012. On July 7, 2012, the tall ships and participating... way. In addition vessels transiting must not maneuver within 100 yards of a tall ship or other vessel...
77 FR 16198 - Safety & Security Zones; OPSAIL 2012 Connecticut, Thames River, New London, CT
Federal Register 2010, 2011, 2012, 2013, 2014
2012-03-20
... Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE., Washington, DC 20590-0001. (4) Hand...'' box. Click ``Search'' then click on the balloon shape in the ``Actions'' column. If you submit your... Facility in Room W12-140 on the ground floor of the Department of Transportation West Building, 1200 New...
DOT National Transportation Integrated Search
2014-08-01
This report describes the instrumentation and data acquisition for the center hung segment in the largest : truss bridge in Connecticut, located on the interstate system. The monitoring system was developed as a : joint effort between researchers at ...
Robinson, Gilpin R.; Peper, John D.; Steeves, Peter A.; Desimone, Leslie A.
1999-01-01
This data layer shows the generalized lithologic and geochemical (lithogeochemical) character of near-surface bedrock in the Connecticut, Housatonic, and Thames River Basins and several other small basins that drain into Long Island Sound from Connecticut. The area includes most of Connecticut, western Massachusetts, eastern Vermont, western New Hampshire, and small parts of Rhode Island, New York, and Quebec, Canada.Bedrock geologic rock units are classified into 29 lithogeochemical rock units, on the basis of the relative reactivity of their constituent minerals to dissolution and other weathering reactions and the presence of carbonate or sulfide minerals. The 29 lithogeochemical units (28 of which can be found in the study area) can be grouped into 6 major categories: (1) carbonate-rich rocks, (2) carbonate-poor, clastic sedimentary rocks restricted to distinct depositional basins, (3) metamorphosed, clastic sedimentary rocks (primarily noncalcareous), (4) mafic igneous rocks and their metamorphic equivalents, (5) ultramafic rocks, and (6) felsic igneous and plutonic rocks and their metamorphic equivalents. The lithogeochemical rock units also are grouped into nine lithologic and physiographic provinces (lithophysiographic domains), which can be further grouped into three major regions: (1) western highlands and lowlands, (2) central lowlands, and (3) eastern highlands.
Mullaney, John R.; Varekamp, J.C.; MCElroy, A.E.; Brsslin, V.T.
2014-01-01
The main rivers that discharge into LIS are the East River in the west, the Housatonic and Connecticut rivers on the north, and the Thames River at the northeastern end of LIS, with the Quinnipiac and several other smaller rivers also coming in from Connecticut. The East River is a tidal strait that connects LIS with New York Harbor through the heart of the New York City metropolitan region. The Housatonic, Quinnipiac, Connecticut and Thames river basins drain agricultural, urban and industrial lands in a watershed that extends from Connecticut north to Canada. The Sound receives contaminants from many sources within and outside its contributing watershed, including direct discharges from coastal industries, wastewater treatment plants (WWTP), urban runoff, and atmospheric deposition. New England has a long history of industrial activity, with factories that once crowded its riverbanks and shores now having succumbed to economic forces that drove manufacturing overseas. Relict deposits with legacy pollutants in upland sediments persist and combine with modern runoff sources from an increasingly densely populated watershed, and continue to be a source of contaminants for LIS. While toxic exposure from legacy and active sources has diminished over the years as wastewater treatment has improved and industries closed or moved away, pockets of contamination still have consequences for many embayments and coves, particularly near urbanized areas of western LIS. Loading of nutrients and carbon have been of recent concern in LIS because of the extensive impacts observed since the mid-1980s. Excess nutrients not only create inhospitable conditions for higher forms of aquatic life through reduced oxygen levels and disrupting trophic dynamics, but also by altering the local biogeochemistry. As a result, the release of toxic substances into the water column may be enhanced in hypoxic waters, thus exerting a toxic effect or enhancing incorporation of toxic pollutants into the food we
37. Photograph of plan for repairs to computer room, 1958, ...
37. Photograph of plan for repairs to computer room, 1958, prepared by the Public Works Office, Underwater Sound Laboratory. Drawing on file at Caretaker Site Office, Naval Undersea Warfare Center, New London. Copyright-free. - Naval Undersea Warfare Center, Bowditch Hall, 600 feet east of Smith Street & 350 feet south of Columbia Cove, West bank of Thames River, New London, New London County, CT
31. Photographic copy of historic views of lecture room, first ...
31. Photographic copy of historic views of lecture room, first floor, Bowditch Hall, c. 1955, taken from album in building photo files in Caretaker Site Office, Naval Undersea Warfare Center, New London. Copyright-free. - Naval Undersea Warfare Center, Bowditch Hall, 600 feet east of Smith Street & 350 feet south of Columbia Cove, West bank of Thames River, New London, New London County, CT
NASA Astrophysics Data System (ADS)
Wainright, S. C.
2016-02-01
A year-long study was performed to investigate seasonal changes in the phytoplankton biomass and primary production in the Thames River, a salt wedge estuary that empties into Long Island Sound in southeastern CT. Chlorophyll measurements were made on discrete filtered samples collected above and below the 1-3 m deep pycnocline at a 5-meter deep station. Surface chlorophyll concentrations, primarily from diatoms, averaged approx. 2 mg m-3, with maxima (up to 10 mg m-3) during summer months (Jun to Aug) and minima during October through March (as low as 0.3 mg m-3). The lower water layer had nearly the same annual average but a smaller range (0.7-3.3 mg m-3) and a winter/spring bloom (Jan-Apr) that was not seen in surface water. During most of the winter, chlorophyll concentrations were higher in the lower layer. Primary production, as measured by 13C uptake in bottle incubations, averaged 67 mgC m-3 h-1 in surface water [range 0.1 (Jan 2012) to 800 mgC m-3 h-1 (Aug 2011)], and 3 mgC m-3 h-1 [range 0.04 (Jan 2012) to 17 mgC m-3 h-1 (Aug 2011)] in the lower layer. On most occasions, deep water incubated near the surface had a higher primary production rate than surface water incubated at the surface; apparently the light-limited phytoplankton in the lower layer were released from light-limitation during these incubations. During the study period there were over a dozen heavy wind or heavy rain events, including Hurricane Irene in August and a freak Nor'easter snow storm in October 2011. Hurricane Irene was associated with a large decline in phytoplankton biomass and primary production. With significant storms as frequent as the rate of sampling, it is difficult to separate a "storm effect" from a background seasonal pattern. The study reveals that phytoplankton, especially those in the lower layer, are light-limited in the Thames River estuary, and that the effects of significant storm events are superimposed on significant seasonal variation.
Coles, J.F.
1996-01-01
Concentrations of organochlorine compounds and trace elements were assayed in fish tissue collected from the Connecticut, Housatonic, and Thames River Basins Study Unit, 1992-94. These data were collected to determine the occurrence and distribution of organochlorine compounds and trace elements in the study unit. Ancillary data included are land-use categories by percentage of the sampling-site basins and the size, gender, and age of the individual fish collected for this study. Concentrations of 28 organochlorine compounds in composited whole fish samples were measured at 32 sites, and concentrations of 22 trace elements in composited fish liver samples were measured at 14 of the 32 sites. Most frequently detected organochlorines were DDT related compounds at 31 sites, total PCBs at 28 sites, and chlordane related compounds at 25 sites. Concentrations of total PCBs in fish tissue were generally higher at the large river sites than at the smaller tributary sites. Concentrations of chlordane-related compounds in fish tissue were higher at sites from more urbanized basins than at sites from predominately agriculture and forested basins. Concentrations of the DDT related compounds were undifferentiated among sites comprising different land uses. Trace elements detected at all 14 sites included boron, copper, iron, manganese, molybdenum, selenium, and zinc. Trace elements detected at 10 or more sites included arsenic, mercury, silver, strontium, and vanadium. Antimony, beryllium, and uranium were not detected at any site.
Horton, Alice A; Jürgens, Monika D; Lahive, Elma; van Bodegom, Peter M; Vijver, Martina G
2018-05-01
Microplastics are widespread throughout aquatic environments. However, there is currently insufficient understanding of the factors influencing ingestion of microplastics by organisms, especially higher predators such as fish. In this study we link ingestion of microplastics by the roach Rutilus rutilus, within the non-tidal part of the River Thames, to exposure and physiological factors. Microplastics were found within the gut contents of roach from six out of seven sampling sites. Of sampled fish, 33% contained at least one microplastic particle. The majority of particles were fibres (75%), with fragments and films also seen (22.7% and 2.3% respectively). Polymers identified were polyethylene, polypropylene and polyester, in addition to a synthetic dye. The maximum number of ingested microplastic particles for individual fish was strongly correlated to exposure (based on distance from the source of the river). Additionally, at a given exposure, the size of fish correlated with the actual quantity of microplastics in the gut. Larger (mainly female) fish were more likely to ingest the maximum possible number of particles than smaller (mainly male) fish. This study is the first to show microplastic ingestion within freshwater fish in the UK and provides valuable new evidence of the factors influencing ingestion that can be used to inform future studies on exposure and hazard of microplastics to fish. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.
1980-08-01
detected. Phase I inspections are not intended to provide detailed hydrologic and hydraulic analyses. In accordance with the esta- blished Guidelines, the...the need for more detailed hydrologic and hydraulic studies, considering the size of the dam, its general condition and the downstream damage...SECTION 5: EVALUATION OF HYDRAULIC /HYDROLOGIC FEATURES U 5.1 General........................................ 5-1 5.2 Design Data
Long-term accumulation and transport of anthropogenic phosphorus in world river basins
NASA Astrophysics Data System (ADS)
Powers, S. M.
2015-12-01
Global food production crucially depends on phosphorus (P). In agricultural and urban landscapes, much P is anthropogenic, entering via trade, and then can be transported by a combination of fluvial and human processes. To date there have been few long-term, large-scale analyses combining both fluvial and human modes of P transport. Here we present reconstructed historical records of anthropogenic P entering and leaving soils and aquatic systems via a combination of trade, infrastructure, food waste, and fluvial fluxes. We then report the net annual P inputs, and the mass of P that has accumulated over the long-term, for entire river basins. Our analyses reveal rapid historical P accumulation for two mixed agricultural-urban landscapes (Thames Basin, UK, Yangtze Basin, China), and one rural agricultural landscape (Maumee Basin, USA). We also show that the human P fluxes massively dominate over the fluvial fluxes in these large basins. For Thames and Maumee Basins, recently there has been modest P depletion/drawdown of the massive P pool accumulated in prior decades, whereas the Yangtze Basin has consistently and rapidly accumulated P since 1980. These first estimates of the magnitude of historical P accumulation in contrasting settings illustrate the scope of management challenges surrounding the storage, fate, exploitation, and reactivation of legacy P that is currently present in the Earth's critical zone.
1981-02-01
probable maximum rainfall for this area is 24 inches in 6 hours for 10 square miles. Using Corps of Engineers I methods , this results in a PMF of...TES rrs r 5 TEST PIT 4 TEST PIT 5 & WACE ELEV 6ai0 XowACfe (LV 5?O.O SLIRFAC EL LV M547 SURfACE ELEVUEDO SunRFdCE ELEV4 jiimv af 09- 0-4 am to-~ rame wro
Federal Register 2010, 2011, 2012, 2013, 2014
2011-07-07
... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. ER11-3913-000] AES Thames, L.L.C.; Supplemental Notice That Initial Market-Based Rate Filing Includes Request for Blanket Section 204 Authorization This is a supplemental notice in the above-referenced proceeding of AES Thames, LLC...
Flood risk and insurance loss potential in the Thames Gateway
NASA Astrophysics Data System (ADS)
Eldridge, J.; Horn, D.
2009-04-01
The Thames Gateway, currently Europe's largest regeneration project, is an area of redevelopment located in the South East of England, with Government plans to create up to 160,000 new homes and 180,000 new jobs by 2016. Although the new development is intended to contribute £12bn annually to the economy, the potential flood risk is high, with much of the area situated on Thames tidal floodplain and vulnerable to both storm surges and peak river flows. This poses significant hazard to those inhabiting the area and has raised concern amongst the UK insurance industry, who would be liable for significant financial claims if a large flood event were to occur, particularly with respect to the number of new homes and businesses being built in flood risk areas. Flood risk and the potential damage to both lives and assets in vulnerable areas have gained substantial recognition, in light of recent flooding events, from both governmental agencies and in the public's awareness of flood hazard. This has resulted in a change in UK policy with planning policy for flood risk (PPS25, Planning Policy Statement 25) adopting a more strategic approach to development, as well as a new Flooding and Water Bill which is due for consultation in 2009. The Government and the Association of British Insurers, who represent the UK insurance industry, have also recently changed their Statement of Principles which guides provision of flood insurance in the future. This PhD research project aims to quantify flood risk in the Thames Gateway area with a view to evaluating the insurance loss potential under different insurance and planning scenarios. Using current sources of inundation extent, and incorporating varying insurance penetration rates and degrees of adoption of planning policy and guidance, it focuses on estimating flood risk under these different scenarios. This presentation introduces the development of the project and the theory and methodology which will be used to address the research problem, and presents the initial findings, including an overview of the major developments going ahead in the area and an indication of areas of high asset value and potential for inundation based on topography and standard of protection of defences.
1980-08-01
Phase I Investigation; however, the investigation is intended to identify any need for such studies . In reviewing this report, it should be realized that...need for more detailed hydrologic and hydraulic studies , considering the size of the dam, its general condition and the downstream damage potential. The...and/or further study . 1-1 I 1.2 DESCRIPTION OF PROJECT a. Location - The dam is located on Hunt’s Brook in a rural area of the Town of Waterford
1979-06-01
Service (DDS), which offers speeds of 19.2K bps and 56K bps. Instead of modems , DDS service requires a Channel Service Unit (CSU), to terminate each...Bell 103 modem that automatically calls for help if the DDS link goes down. DDS users can also use their own schemes to protect their transmissions...Switched 56 service provides 700 numbers for 56K transmission in some 60 odd cities, including areas such as Orlando, San Diego, and the Washington
1984-10-13
41G-121-139 (5-13 Oct. 1984) --- The Strait of Dover and London, seldom seen in space photography, can be delineated in this medium format camera's scene showing parts of England and France from onboard the Earth-orbiting space shuttle Challenger. Parts of the Thames River can also be traced in the frame. The 41-G crew consisted of astronauts Robert L. Crippen, commander; Jon A. McBride, pilot; and Mission Specialists Kathryn D. Sullivan, Sally K. Ride, and David D. Leestma; along with Canadian astronaut Marc Garneau; and Paul D. Scully-Power, both payload specialists. Photo credit: NASA
Federal Register 2010, 2011, 2012, 2013, 2014
2010-03-08
... Decree (``Decree'') in United States v. AES Thames, LLC, Civil Action No. 3:10cv281, was lodged with the... States against AES Thames, LLC under the Clean Air Act, 42 U.S.C. 7401-7671q, the Clean Water Act, 33 U.S... injunctive relief and recovery of civil penalties in connection with AES Thames, LLC's operation of a coal...
NASA Astrophysics Data System (ADS)
Wade, A. J.; Palmer-Felgate, E. J.; Halliday, S. J.; Skeffington, R. A.; Loewenthal, M.; Jarvie, H. P.; Bowes, M. J.; Greenway, G. M.; Haswell, S. J.; Bell, I. M.; Joly, E.; Fallatah, A.; Neal, C.; Williams, R. J.; Gozzard, E.; Newman, J. R.
2012-05-01
This paper introduces new insights into the hydrochemical functioning of lowland river-systems using field-based spectrophotometric and electrode technologies. The streamwater concentrations of nitrogen species and phosphorus fractions were measured at hourly intervals on a continuous basis at two contrasting sites on tributaries of the River Thames, one draining a rural catchment, the River Enborne, and one draining a more urban system, The Cut. The measurements complement those from an existing network of multi-parameter water quality sondes maintained across the Thames catchment and weekly monitoring based on grab samples. The results of the sub-daily monitoring show that streamwater phosphorus concentrations display highly complex, seemingly chaotic, dynamics under storm conditions dependent on the antecedent catchment wetness, and that diurnal phosphorus and nitrogen cycles occur under low flow conditions. The diurnal patterns highlight the dominance of sewage inputs in controlling the streamwater phosphorus and nitrogen concentrations at low flows, even at a distance of 7 km from the nearest sewage works in the rural, River Enborne, and that the time of sample collection is important when judging water quality against ecological thresholds or standards. An exhaustion of the supply of phosphorus from diffuse and septic tank sources during storm events was evident and load estimation was not improved by sub-daily monitoring beyond that achieved by daily sampling because of the eventual reduction in the phosphorus mass entering the stream during events. The dominance of respiration over photosynthesis in The Cut indicated a prevalence of heterotrophic algae, and the seasonal patterns in respiration and photosynthesis corresponded with those of temperature and light in this nutrient over-enriched stream. These results highlight the utility of sub-daily water quality measurements but the deployment of modified wet-chemistry technologies into the field was limited by mains electricity availability. A new approach is therefore needed to allow measurement of a wide range of analytes at a broader range of locations for the development of water quality web-sensor networks. The development and field deployment of a miniaturised "lab-on-a-chip" ion chromatograph is proposed and justified.
Moorhouse, H L; Read, D S; McGowan, S; Wagner, M; Roberts, C; Armstrong, L K; Nicholls, D J E; Wickham, H D; Hutchins, M G; Bowes, M J
2018-05-15
Recent river studies have observed rapid phytoplankton dynamics, driven by diurnal cycling and short-term responses to storm events, highlighting the need to adopt new high-frequency characterisation methods to understand these complex ecological systems. This study utilised two such analytical methods; pigment analysis by high performance liquid chromatography (HPLC) and cell counting by flow cytometry (FCM), alongside traditional chlorophyll spectrophotometry and light microscopy screening, to characterise the major phytoplankton bloom of 2015 in the River Thames, UK. All analytical techniques observed a rapid increase in chlorophyll a concentration and cell abundances from March to early June, caused primarily by a diatom bloom. Light microscopy identified a shift from pennate to centric diatoms during this period. The initial diatom bloom coincided with increased HPLC peridinin concentrations, indicating the presence of dinoflagellates which were likely to be consuming the diatom population. The diatom bloom declined rapidly in early June, coinciding with a storm event. There were low chlorophyll a concentrations (by both HPLC and spectrophotometric methods) throughout July and August, implying low biomass and phytoplankton activity. However, FCM revealed high abundances of pico-chlorophytes and cyanobacteria through July and August, showing that phytoplankton communities remain active and abundant throughout the summer period. In combination, these techniques are able to simultaneously characterise a wider range of phytoplankton groups, with greater certainty, and provide improved understanding of phytoplankton functioning (e.g. production of UV inhibiting pigments by cyanobacteria in response to high light levels) and ecological status (through examination of pigment degradation products). Combined HPLC and FCM analyses offer rapid and cost-effective characterisation of phytoplankton communities at appropriate timescales. This will allow a more-targeted use of light microscopy to capture phytoplankton peaks or to investigate periods of rapid community succession. This will lead to greater system understanding of phytoplankton succession in response to biogeochemical drivers. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.
1980-08-01
ant Stru-.i~ d. Reservoir Alea e. Downstream Channfel 3.2 Evaluation .................... ....... 3- SECTION 4: OPERATIONAL AND MAINTENAmCE PROCEDURES...6,500 3.43 1,895 16. Union Village 110,000 126.0 873 17. North Hartland 199,000 220.0 904 18. North Springfield 157,000 158.0 994 19. Ball Mountain ...190,000 172.0 1,105 20. Townshend 228,000 106.0(278 total) 820 21. Surry Mountain 63,000 100.0 630 22. Otter Brook 45,000 47.0 957 23. Birch Hill
1980-09-01
purpose of a Phase I Investigation is to identify expeditiously - those dams which may pose hazards to human life or property. The assessment of the general...calculatec by the Soil Loss Formula (0.1 ton/ac/yr. y±cld). The dosianed heiGht of the structures vill provide st rage for a 50 year sediment...As shown in the above listing the design meet, the c:rr,1 ,ia established in all instances. L B-13 rage -,- n We have discussed with the S. C.S
An evaluation of Dynamic TOPMODEL in natural and human-impacted catchments for low flow simulation
NASA Astrophysics Data System (ADS)
Coxon, Gemma; Freer, Jim; Lane, Rosanna; Musuuza, Jude; Woods, Ross; Wagener, Thorsten; Howden, Nicholas
2017-04-01
Models of catchment hydrology are essential tools for drought risk management, often providing input to water resource system models, aiding our understanding of low flow processes within catchments and providing low flow simulations and predictions. However, simulating low flows is challenging as hydrological systems often demonstrate threshold effects in connectivity, non-linear groundwater contributions and a greater influence of anthropogenic modifications such as surface and ground water abstractions during low flow periods. These processes are typically not well represented in commonly used hydrological models due to knowledge, data and model limitations. Hence, a better understanding of the natural and human processes that occur during low flows, how these are represented within models and how they could be improved is required to be able to provide robust and reliable predictions of future drought events. The aim of this study is to assess the skill of dynamic TOPMODEL during low flows for both natural and human-impacted catchments. Dynamic TOPMODEL was chosen for this study as it is able to explicitly characterise connectivity and fluxes across landscapes using hydrological response units (HRU's) while still maintaining flexibility in how spatially complex the model is configured and what specific functions (i.e. abstractions or groundwater stores) are represented. We apply dynamic TOPMODEL across the River Thames catchment using daily time series of observed rainfall and potential evapotranspiration data for the period 1999 - 2014, covering two major droughts in the Thames catchment. Significantly, to assess the impact of abstractions on low flows across the Thames catchment, we incorporate functions to characterise over 3,500 monthly surface water and ground water abstractions covering the simulation period into dynamic TOPMODEL. We evaluate dynamic TOPMODEL at over 90 gauging stations across the Thames catchment against multiple signatures of catchment low-flow behaviour in a 'limits of acceptability' GLUE framework. We investigate differences in model performance between signatures, different low flow periods and for natural and human impacted catchments to better understand the ability of dynamic TOPMODEL to represent low flows in space and time. Finally, we discuss future developments of dynamic TOPMODEL to improve low flow simulation and the implications of these results for modelling hydrological extremes in natural and human impacted catchments across the UK and the world.
Human impact on long-term organic carbon export to rivers
NASA Astrophysics Data System (ADS)
Noacco, Valentina; Wagener, Thorsten; Worrall, Fred; Burt, Tim P.; Howden, Nicholas J. K.
2017-04-01
Anthropogenic landscape alterations have increased global carbon transported by rivers to oceans since preindustrial times. Few suitable observational data sets exist to distinguish different drivers of carbon increase, given that alterations only reveal their impact on fluvial dissolved organic carbon (DOC) over long time periods. We use the world's longest record of DOC concentrations (130 years) to identify key drivers of DOC change in the Thames basin (UK). We show that 90% of the long-term rise in fluvial DOC is explained by increased urbanization, which released to the river 671 kt C over the entire period. This source of carbon is linked to rising population, due to increased sewage effluent. Soil disturbance from land use change explained shorter-term fluvial responses. The largest land use disturbance was during the Second World War, when almost half the grassland area in the catchment was converted into arable land, which released 45 kt C from soils to the river. Carbon that had built up in soils over decades was released to the river in only a few years. Our work suggests that widespread population growth may have a greater influence on fluvial DOC trends than previously thought.
Validated predictive modelling of the environmental resistome
Amos, Gregory CA; Gozzard, Emma; Carter, Charlotte E; Mead, Andrew; Bowes, Mike J; Hawkey, Peter M; Zhang, Lihong; Singer, Andrew C; Gaze, William H; Wellington, Elizabeth M H
2015-01-01
Multi-drug-resistant bacteria pose a significant threat to public health. The role of the environment in the overall rise in antibiotic-resistant infections and risk to humans is largely unknown. This study aimed to evaluate drivers of antibiotic-resistance levels across the River Thames catchment, model key biotic, spatial and chemical variables and produce predictive models for future risk assessment. Sediment samples from 13 sites across the River Thames basin were taken at four time points across 2011 and 2012. Samples were analysed for class 1 integron prevalence and enumeration of third-generation cephalosporin-resistant bacteria. Class 1 integron prevalence was validated as a molecular marker of antibiotic resistance; levels of resistance showed significant geospatial and temporal variation. The main explanatory variables of resistance levels at each sample site were the number, proximity, size and type of surrounding wastewater-treatment plants. Model 1 revealed treatment plants accounted for 49.5% of the variance in resistance levels. Other contributing factors were extent of different surrounding land cover types (for example, Neutral Grassland), temporal patterns and prior rainfall; when modelling all variables the resulting model (Model 2) could explain 82.9% of variations in resistance levels in the whole catchment. Chemical analyses correlated with key indicators of treatment plant effluent and a model (Model 3) was generated based on water quality parameters (contaminant and macro- and micro-nutrient levels). Model 2 was beta tested on independent sites and explained over 78% of the variation in integron prevalence showing a significant predictive ability. We believe all models in this study are highly useful tools for informing and prioritising mitigation strategies to reduce the environmental resistome. PMID:25679532
Validated predictive modelling of the environmental resistome.
Amos, Gregory C A; Gozzard, Emma; Carter, Charlotte E; Mead, Andrew; Bowes, Mike J; Hawkey, Peter M; Zhang, Lihong; Singer, Andrew C; Gaze, William H; Wellington, Elizabeth M H
2015-06-01
Multi-drug-resistant bacteria pose a significant threat to public health. The role of the environment in the overall rise in antibiotic-resistant infections and risk to humans is largely unknown. This study aimed to evaluate drivers of antibiotic-resistance levels across the River Thames catchment, model key biotic, spatial and chemical variables and produce predictive models for future risk assessment. Sediment samples from 13 sites across the River Thames basin were taken at four time points across 2011 and 2012. Samples were analysed for class 1 integron prevalence and enumeration of third-generation cephalosporin-resistant bacteria. Class 1 integron prevalence was validated as a molecular marker of antibiotic resistance; levels of resistance showed significant geospatial and temporal variation. The main explanatory variables of resistance levels at each sample site were the number, proximity, size and type of surrounding wastewater-treatment plants. Model 1 revealed treatment plants accounted for 49.5% of the variance in resistance levels. Other contributing factors were extent of different surrounding land cover types (for example, Neutral Grassland), temporal patterns and prior rainfall; when modelling all variables the resulting model (Model 2) could explain 82.9% of variations in resistance levels in the whole catchment. Chemical analyses correlated with key indicators of treatment plant effluent and a model (Model 3) was generated based on water quality parameters (contaminant and macro- and micro-nutrient levels). Model 2 was beta tested on independent sites and explained over 78% of the variation in integron prevalence showing a significant predictive ability. We believe all models in this study are highly useful tools for informing and prioritising mitigation strategies to reduce the environmental resistome.
Wind observations above an urban river using a new lidar technique, scintillometry and anemometry.
Wood, C R; Pauscher, L; Ward, H C; Kotthaus, S; Barlow, J F; Gouvea, M; Lane, S E; Grimmond, C S B
2013-01-01
Airflow along rivers might provide a key mechanism for ventilation in cities: important for air quality and thermal comfort. Airflow varies in space and time in the vicinity of rivers. Consequently, there is limited utility in point measurements. Ground-based remote sensing offers the opportunity to study 3D airflow in locations which are difficult to observe with conventional approaches. For three months in the winter and spring of 2011, the airflow above the River Thames in central London was observed using a scanning Doppler lidar, a scintillometer and sonic anemometers. First, an inter-comparison showed that lidar-derived mean wind-speed estimates compare almost as well to sonic anemometers (root-mean-square error (rmse) 0.65-0.68 ms(-1)) as comparisons between sonic anemometers (0.35-0.73 ms(-1)). Second, the lidar duo-beam operating strategy provided horizontal transects of wind vectors (comparison with scintillometer rmse 1.12-1.63 ms(-1)) which revealed mean and turbulent airflow across the river and surrounds; in particular, channelled airflow along the river and changes in turbulence quantities consistent with the roughness changes between built and river environments. The results have important consequences for air quality and dispersion around urban rivers, especially given that many cities have high traffic rates on roads located on riverbanks. Copyright © 2012 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Goncharov, A. E.; Mednikov, D. M.; Karelin, N. M.; Nasyrov, I. R.
2016-11-01
Current progress in underwater archeology is based on a rich arsenal of high-tech appliances, among which sonar technology plays a key role; it enables scientists not only to detect submerged archeological objects, but to examine them in high definition without having to conduct diving operations or use expensive underwater unmanned vehicles. While the majority of sensational scientific discoveries using sonar have been made in saltwater environments, freshwater ones, rivers in particular, have seen limited activity. The river Yenisei in central Siberia contains an unrecorded number of shipwrecks that await being discovered and studied. In this article we focus on the peculiarities of using sonar for detecting archeological sites on the Yenisei. This article is based on the results of the 2016 expedition, which has determined the location of Thames, a 19th century British steam schooner which was wrecked on the Yenisei.
The Observers Observed: Charles Dickens at the Royal Observatory, Greenwich, in 1850
NASA Astrophysics Data System (ADS)
Chapman, A.
2005-12-01
In 1850 the magazine Household Words, which Charles Dickens edited, published three articles describing the instruments and workings of the Royal Observatory, Greenwich. These 'popular' articles are invaluable primary sources for the historian of astronomy. They convey some of the Victorian public's fascination with an Institution believed by some to be a lighthouse for night-time shipping on the river Thames; by others, a national repository of 'divining rods' and 'magic mirrors'. Dickens was clearly impressed by the pragmatic usefulness of the Observatory to a commercial and maritime nation, and by seemingly magical, self-acting and recording instruments whereby the wind wrote its own 'Aeolian Autobiography'.
Spatial and temporal variations of river nitrogen exports from major basins in China.
Ti, Chaopu; Yan, Xiaoyuan
2013-09-01
Provincial-level data for population, livestock, land use, economic growth, development of sewage systems, and wastewater treatment rates were used to construct a river nitrogen (N) export model in this paper. Despite uncertainties, our results indicated that river N export to coastal waters increased from 531 to 1,244 kg N km(-2) year(-1) in the Changjiang River basin, 107 to 223 kg N km(-2) year(-1) in the Huanghe River basin, and 412 to 1,219 kg N km(-2) year(-1) in the Zhujiang River basin from 1980 to 2010 as a result of rapid population and economic growth. Significant temporal changes in water N sources showed that as the percentage of runoff from croplands increased, contributions of natural system runoff and rural human and livestock excreta decreased in the three basins from 1980 to 2010. Moreover, the nonpoint source N decreased from 72 to 58 % in the Changjiang River basin, 80 to 67 % in the Huanghe River basin, and 69 to 51 % in the Zhujiang River basin, while the contributions of point sources increased greatly during the same period. Estimated results indicated that the N concentrations in the Changjiang, Huanghe, and Zhujiang rivers during 1980-2004 were higher than those in the St. Lawrence River in Canada and lower than those in the Thames, Donau, Rhine, Seine, and Han rivers during the same period. River N export will reduce by 58, 54, and 57 % for the Changjiang River, Huanghe River, and Zhujiang River in the control scenario in 2050 compared with the basic scenario.
NASA Astrophysics Data System (ADS)
Cigna, Francesca; Jordan, Hannah; Bateson, Luke; McCormack, Harry; Roberts, Claire
2015-11-01
We combine geological data and ground motion estimates from satellite ERS-1/2 and ENVISAT persistent scatterer interferometry (PSI) to delineate areas of observed natural and anthropogenic geohazards in the administrative area of Greater London (United Kingdom). This analysis was performed within the framework of the EC FP7-SPACE PanGeo project, and by conforming to the interpretation and geohazard mapping methodology extensively described in the Production Manual (cf. http://www.pangeoproject.eu). We discuss the results of the generation of the PanGeo digital geohazard mapping product for Greater London, and analyse the potential of PSI, geological data and the PanGeo methodology to identify areas of observed geohazards. Based on the analysis of PSI ground motion data sets for the years 1992-2000 and 2002-2010 and geology field campaigns, we identify 25 geohazard polygons, covering a total of ~650 km2. These include not only natural processes such as compaction of deposits on the River Thames flood plain and slope instability, but also anthropogenic instability due to groundwater management and changes in the Chalk aquifer, recent engineering works such as those for the Jubilee Line Extension project and electricity tunnelling in proximity to the River Thames, and the presence of made ground. In many instances, natural and anthropogenic observed geohazards overlap, therefore indicating interaction of different processes over the same areas. In terms of ground area covered, the dominant geohazard is anthropogenic land subsidence caused by groundwater abstraction for a total of ~300 km2, followed by natural compression of River Thames sediments over ~105 km2. Observed ground motions along the satellite line-of-sight are as high as +29.5 and -25.3 mm/year, and indicate a combination of land surface processes comprising ground subsidence and uplift, as well as downslope movements. Across the areas of observed geohazards, urban land cover types from the Copernicus (formerly GMES) EEA European Urban Atlas, e.g., continuous and discontinuous urban fabric and industrial units, show the highest average velocities away from the satellite sensor, and the smallest standard deviations (~0.7-1.0 mm/year). More rural land cover types such as agricultural, semi-natural and green areas reveal the highest spatial variability (up to ~4.4 mm/year), thus suggesting greater heterogeneity of observed motion rates within these land cover types. Areas of observed motion in the PSI data for which a geological interpretation cannot be found with sufficient degree of certainty are also identified, and their possible causes discussed. Although present in Greater London, some geohazard types such as shrink-swell clays and ground dissolution are not highlighted by the interpretation of PSI annual motion rates. Reasons for absence of evidence of the latter in the PSI data are discussed, together with difficulties related to the identification of good radar scatterers in landsliding areas.
NASA Astrophysics Data System (ADS)
Whelan, M. J.; Burt, T. P.; Howden, N. K.; Worrall, F.
2012-12-01
Nitrate concentrations and fluxes in many of the world's rivers have increased over the latter part of the 20th Century leading to freshwater and, more frequently, marine eutrophication. This has largely been linked to agricultural intensification which has increased food production via a combination of improved methods, crop varieties, pest control technologies, mechanisation and fertiliser use. The area of land under intensive production has also increased in many watersheds. Here we analyse long term water quality records from a number of UK rivers to assess temporal patterns of nitrate concentrations and fluxes and to identify driving factors. The data, which include the world's longest record of nitrate concentrations from the River Thames, London (1868 to 2008), show that dramatic and sustained increases in nitrate concentrations and fluxes occurred after periods of substantial land use change including the conversion of significant areas of permanent pasture to arable production in the 1940s and 1960s and increases in fertiliser use in the 1960s. Grassland to arable conversion can release large quantities of nitrate due to the enhanced mineralisation of the extra soil organic nitrogen which accumulates in pasture systems. Recent attempts to reverse these increases, such as widespread restrictions of nitrogen inputs have, thus far, been relatively ineffective, although there have been recent indications that levels have stabilised in some watersheds. Our analysis clearly shows the dominance of land use change over other potential drivers such as waste water emission, climatic and hydrological changes and suggests that current measures for the mitigation of large-scale diffuse pollution based on limiting fertiliser use are not drastic enough to reverse significantly the increases in riverine nitrate concentrations which have been observed. Analysis of the long term data also shows that trend detection is problematic for periods less than about 15 years, without a longer term historical context. The data and associated analysis support the continued maintenance of very long benchmark monitoring sites to identify trends and adequately assess the drivers of environmental change. Nitrate concentrations measured in the river Thames since 1868 showing drammatic increases in the latter half of the 20th century. Red line shows annual average concentration.
NASA Astrophysics Data System (ADS)
Neal, C.
2007-01-01
Variations in concentration of yttrium (Y), lanthanum (La), cerium (Ce), neodymium (Nd), samarium (Sm) and gadolinium (Gd) among rivers of eastern England and the border with Scotland are described in relation to the dissolved (<0.45 µM) fraction and acid-available particulate (AAP) fractions. The rivers cover a range of rural, agricultural and urban/industrial environments. Yttrium and the lanthanides show significant levels of both dissolved and acid-available particulate forms (typically about 40% in the dissolved form). For the dissolved phase, Y and the lanthanides are linearly correlated with each other and with iron: most of this dissolved component may be in a micro-particulate/colloidal form. The Y and lanthanide relationships show marked scatter and there are anomalously high La concentrations at times for the rivers Great Ouse, Thames and Wear that are probably linked to pollutant sources. For the Ouse, and especially for one of its tributaries, the Swale, relatively high Sm concentrations are probably associated with mineralisation within the catchment and contamination of the associated flood plain. For the AAP components, there are strong linear relationships with Y and the lanthanides across all the rivers. There is also a strong link between these AAP associated REE and AAP iron, although the scatter is greater and the industrial rivers have a lower lanthanide to iron ratio, probably due to iron-rich contaminants.
NASA Astrophysics Data System (ADS)
Nehlich, Olaf; Fuller, Benjamin T.; Jay, Mandy; Mora, Alice; Nicholson, Rebecca A.; Smith, Colin I.; Richards, Michael P.
2011-09-01
This study investigates the application of sulphur isotope ratios (δ 34S) in combination with carbon (δ 13C) and nitrogen (δ 15N) ratios to understand the influence of environmental sulphur on the isotopic composition of archaeological human and faunal remains from Roman era sites in Oxfordshire, UK. Humans ( n = 83), terrestrial animals ( n = 11), and freshwater fish ( n = 5) were analysed for their isotope values from four locations in the Thames River Valley, and a broad range of δ 34S values were found. The δ 34S values from the terrestrial animals were highly variable (-13.6‰ to +0.5‰), but the δ 34S values of the fish were clustered and 34S-depleted (-20.9‰ to -17.3‰). The results of the faunal remains suggest that riverine sulphur influenced the terrestrial sulphur isotopic signatures. Terrestrial animals were possibly raised on the floodplains of the River Thames, where highly 34S-depleted sulphur influenced the soil. The humans show the largest range of δ 34S values (-18.8‰ to +9.6‰) from any archaeological context to date. No differences in δ 34S values were found between the males (-7.8 ± 6.0‰) and females (-5.3 ± 6.8‰), but the females had a linear correlation ( R2 = 0.71; p < 0.0001) between their δ 15N and δ 34S compositions. These δ 34S results suggest a greater dietary variability for the inhabitants of Roman Oxfordshire than previously thought, with some individuals eating solely terrestrial protein resources and others showing a diet almost exclusively based on freshwater protein such as fish. Such large dietary variability was not visible by analysing only the carbon and nitrogen isotope ratios, and this research represents the largest and most detailed application of δ 34S analysis to examine dietary practices (including breastfeeding and weaning patterns) during the Romano-British Period.
NASA Astrophysics Data System (ADS)
Ragab, R.; Rosier, P.; Dixon, A.; Bromley, J.; Cooper, J. D.
2003-08-01
Lack of accurate data has led some hydrologists and city planners to assume that urban infiltration is zero and runoff is 100% of the rainfall. These assumptions lead to an over estimation of road runoff volume and an underestimation of direct recharge to groundwater, which is already rising under some UK cities. This study investigates infiltration and runoff processes and quantifies the percentage of rainfall that contributes to storm drainage, and that which infiltrates through different types of road surface. Access tubes were installed for measuring soil water content using a neutron probe in three car parks, a road and a grass site at the Centre for Ecology and Hydrology, Crowmarsh Gifford, Wallingford. Storm drainage was recorded at the exit of the Thamesmead Estate in Crowmarsh Gifford, just before the drain joins the River Thames at Wallingford. Rainfall and water table depth were also recorded. Weekly measurements of soil moisture content indicated that the top 40 cm layer is not influenced by water-table fluctuations and, therefore, positive changes in soil moisture could be attributed to infiltration of rainfall through the surface. Depending on the nature of the surface, subsurface layers, level of traffic, etc., between 6 and 9% of rainfall was found to infiltrate through the road surfaces studied. The storm drainage generated by road runoff revealed a flow pattern similar to that of the receiving watercourse (River Thames) and increased with the increase of infiltration and soil water content below the road surface. The ratio of runoff to rainfall was 0·7, 0·9 and 0·5 for annual, winter (October-March) and summer (April-September) respectively. As the results of the infiltration indicated that 6 to 9% of annual rainfall infiltrates through the road surface, this means that evaporation represents, 21-24% of annual rainfall, with more evaporation taking place during summer than winter.
Harris, T.; Silver, T.; Rink, E.; Hilton, S.
1996-01-01
OBJECTIVE--To identify the nature and extent of any vocational training deficit within the London initiative zone and investigate the reasons. DESIGN--Collation of statistics and postal questionnaire surveys. SETTING--Thames regions inside and outside the London initiative zone. SUBJECTS--General practice registrars, trainers, principals from non-training practices, and vocational training course organisers. MAIN OUTCOME MEASURES--Trends in numbers of general practice registrars, proportions of trainers, views on current vocational training in inner London. RESULTS--Numbers of general practice registrars fell significantly between 1988 and 1993 within the London initiative zone and in England overall. The number of registrars within the zone fell by more than in the rest of the Thames regions, where the decline was not statistically significant. A lower proportion of principals were approved as trainers within the zone than in the rest of the Thames regions and England overall. In their responses to the survey (88% of inner London registrars responded and 81% of outer Thames registrars) registrars suggested that improving remuneration and personal safety would make training in London more attractive. Trainers and non-trainers (response rates 89% and 66% respectively) also suggested increasing remuneration for trainers together with more protected time for training. CONCLUSIONS--Less vocational training takes place within the London initiative zone than in the rest of the Thames regions and England overall, although there are discrepancies in official statistics. As well as specific recommendations for improving recruitment to vocational training in inner London, measures to tackle inner city deprivation should also remain high on the political agenda. PMID:8555940
Assessing climate change and socio-economic uncertainties in long term management of water resources
NASA Astrophysics Data System (ADS)
Jahanshahi, Golnaz; Dawson, Richard; Walsh, Claire; Birkinshaw, Stephen; Glenis, Vassilis
2015-04-01
Long term management of water resources is challenging for decision makers given the range of uncertainties that exist. Such uncertainties are a function of long term drivers of change, such as climate, environmental loadings, demography, land use and other socio economic drivers. Impacts of climate change on frequency of extreme events such as drought make it a serious threat to water resources and water security. The release of probabilistic climate information, such as the UKCP09 scenarios, provides improved understanding of some uncertainties in climate models. This has motivated a more rigorous approach to dealing with other uncertainties in order to understand the sensitivity of investment decisions to future uncertainty and identify adaptation options that are as far as possible robust. We have developed and coupled a system of models that includes a weather generator, simulations of catchment hydrology, demand for water and the water resource system. This integrated model has been applied in the Thames catchment which supplies the city of London, UK. This region is one of the driest in the UK and hence sensitive to water availability. In addition, it is one of the fastest growing parts of the UK and plays an important economic role. Key uncertainties in long term water resources in the Thames catchment, many of which result from earth system processes, are identified and quantified. The implications of these uncertainties are explored using a combination of uncertainty analysis and sensitivity testing. The analysis shows considerable uncertainty in future rainfall, river flow and consequently water resource. For example, results indicate that by the 2050s, low flow (Q95) in the Thames catchment will range from -44 to +9% compared with the control scenario (1970s). Consequently, by the 2050s the average number of drought days are expected to increase 4-6 times relative to the 1970s. Uncertainties associated with urban growth increase these risks further. Adaptation measures, such as new reservoirs can manage these risks to a certain extent, but our sensitivity testing demonstrates that they are less robust to future uncertainties than measures taken to reduce water demand. Keywords: Climate change, Uncertainty, Decision making, Drought, Risk, Water resources management.
The water footprint of agricultural products in European river basins
NASA Astrophysics Data System (ADS)
Vanham, D.; Bidoglio, G.
2014-05-01
This work quantifies the agricultural water footprint (WF) of production (WFprod, agr) and consumption (WFcons, agr) and the resulting net virtual water import (netVWi, agr) of 365 European river basins for a reference period (REF, 1996-2005) and two diet scenarios (a healthy diet based upon food-based dietary guidelines (HEALTHY) and a vegetarian (VEG) diet). In addition to total (tot) amounts, a differentiation is also made between the green (gn), blue (bl) and grey (gy) components. River basins where the REF WFcons, agr, tot exceeds the WFprod, agr, tot (resulting in positive netVWi, agr, tot values), are found along the London-Milan axis. These include the Thames, Scheldt, Meuse, Seine, Rhine and Po basins. River basins where the WFprod, agr, tot exceeds the WFcons, agr, tot are found in Western France, the Iberian Peninsula and the Baltic region. These include the Loire, Ebro and Nemunas basins. Under the HEALTHY diet scenario, the WFcons, agr, tot of most river basins decreases (max -32%), although it was found to increase in some basins in northern and eastern Europe. This results in 22 river basins, including the Danube, shifting from being net VW importers to being net VW exporters. A reduction (max -46%) in WFcons, agr, tot is observed for all but one river basin under the VEG diet scenario. In total, 50 river basins shift from being net VW importers to being net exporters, including the Danube, Seine, Rhone and Elbe basins. Similar observations are made when only the gn + bl and gn components are assessed. When analysing only the bl component, a different river basin pattern is observed.
Incorporating Model Parameter Uncertainty into Prostate IMRT Treatment Planning
2005-04-01
HD HJ. Fractionation in radiotherapy. London: Taylor & Francis, 1987. 8. Withers HR. Biologic basis for altered fractionation schemes. Cancer 1985; 55...of combined agent regimens. Int J Radiat Biol 1990; 57: 709-722. 15. Thames HD , Jr., Withers HR, Peters LJ, Fletcher GH. Changes in early and late...Oncology, Biology, Physics 2001; 50: 551-560. 30. Turesson I, Thames HD . Repair capacity and kinetics of human skin during fractionated radiotherapy
Holbrook, Christopher; Jubar, Aaron K.; Barber, Jessica M.; Tallon, Kevin; Hondorp, Darryl W.
2016-01-01
Adult sea lamprey (Petromyzon marinus) abundance in Lake Erie has remained above targets set by fishery managers since 2005, possibly due to increased recruitment in the St. Clair-Detroit River System (SCDRS). Sea lamprey recruitment in the SCDRS poses an enormous challenge to sea lamprey control and assessment in Lake Erie because the SCDRS contains no dams to facilitate capture and discharge is at least an order of magnitude larger in the SCDRS than most other sea lamprey-producing tributaries in the Great Lakes. As a first step toward understanding population size, spatial distribution, and spawning habitat of adult sea lampreys in the SCDRS, we used acoustic telemetry to determine where sea lampreys ceased migration (due to spawning, death, or both) among major regions of the SCDRS. All tagged sea lampreys released in the lower Detroit River (N = 27) moved upstream through the Detroit River and entered Lake St. Clair. After entering Lake St. Clair, sea lampreys entered the St. Clair River (N = 22), Thames River (N = 1), or were not detected again (N = 4). Many sea lampreys (10 of 27) were last observed moving downstream (“fallback”) but we were unable to determine if those movements occurred before or after spawning, or while sea lampreys were dead or alive. Regardless of whether estimates of locations where sea lampreys ceased migration were based on the most upstream region occupied or final region occupied, most sea lampreys ceased migration in the St. Clair River or Lake St. Clair. Results suggest that spawning and rearing in the St. Clair River could be an important determinant of sea lamprey recruitment in the SCDRS and may direct future assessment and control activities in that system.
The water quality of the LOCAR Pang and Lambourn catchments
NASA Astrophysics Data System (ADS)
Neal, C.; Jarvie, H. P.; Wade, A. J.; Neal, M.; Wyatt, R.; Wickham, H.; Hill, L.; Hewitt, N.
The water quality of the Pang and Lambourn, tributaries of the River Thames, in south-eastern England, is described in relation to spatial and temporal dimensions. The river waters are supplied mainly from Chalk-fed aquifer sources and are, therefore, of a calcium-bicarbonate type. The major, minor and trace element chemistry of the rivers is controlled by a combination of atmospheric and pollutant inputs from agriculture and sewage sources superimposed on a background water quality signal linked to geological sources. Water quality does not vary greatly over time or space. However, in detail, there are differences in water quality between the Pang and Lambourn and between sites along the Pang and the Lambourn. These differences reflect hydrological processes, water flow pathways and water quality input fluxes. The Pang’s pattern of water quality change is more variable than that of the Lambourn. The flow hydrograph also shows both a cyclical and "uniform pattern" characteristic of aquifer drainage with, superimposed, a series of "flashier" spiked responses characteristic of karstic systems. The Lambourn, in contrast, shows simpler features without the "flashier" responses. The results are discussed in relation to the newly developed UK community programme LOCAR dealing with Lowland Catchment Research. A descriptive and box model structure is provided to describe the key features of water quality variations in relation to soil, unsaturated and groundwater flows and storage both away from and close to the river.
Neal, Colin; Williams, Richard J; Bowes, Michael J; Harrass, Michael C; Neal, Margaret; Rowland, Philip; Wickham, Heather; Thacker, Sarah; Harman, Sarah; Vincent, Colin; Jarvie, Helen P
2010-02-15
The changing patterns of riverine boron concentration are examined for the Thames catchment in southern/southeastern England using data from 1997 to 2007. Boron concentrations are related to an independent marker for sewage effluent, sodium. The results show that boron concentrations in the main river channels have declined with time especially under baseflow conditions when sewage effluent dilution potential is at its lowest. While boron concentrations have reduced, especially under low-flow conditions, this does not fully translate to a corresponding reduction in boron flux and it seems that the "within-catchment" supplies of boron to the river are contaminated by urban sources. The estimated boron reduction in the effluent input to the river based on the changes in river chemistry is typically around 60% and this figure matches with an initial survey of more limited data for the industrial north of England. Data for effluent concentrations at eight sewage treatment works within the Kennet also indicate substantial reductions in boron concentrations: 80% reduction occurred between 2001 and 2008. For the more contaminated rivers there are issues of localised rather than catchment-wide sources and uncertainties over the extent and nature of water/boron stores. Atmospheric sources average around 32 to 61% for the cleaner and 4 to 14% for the more polluted parts. The substantial decreases in the boron concentrations correspond extremely well with the timing and extent of European wide trends for reductions in the industrial and domestic usage of boron-bearing compounds. It clearly indicates that such reductions have translated into lower average and peak concentrations of boron in the river although the full extent of these reductions has probably not yet occurred due to localised stores that are still to deplete.
Riverine fish diversity varies according to geographical isolation and land use modification.
Nicol, Elizabeth; Stevens, Jamie R; Jobling, Susan
2017-10-01
Understanding the environmental factors driving species-genetic diversity correlations (SGDCs) is critical for designing appropriate conservation and management strategies to protect biodiversity. Yet, few studies have explored the impact of changing land use patterns on SGDCs specifically in aquatic communities. This study examined patterns of genetic diversity in roach ( Rutilus rutilus L.) together with fish species composition across 19 locations in a large river catchment, spanning a gradient in land use. Our findings show significant correlations between some, but not all, species and genetic diversity end points. For example, genetic and species differentiation showed a weak but significant linear relationship across the Thames catchment, but additional diversity measures such as allelic richness and fish population abundance did not. Further examination of patterns in species and genetic diversity indicated that land use intensification has a modest effect on fish diversity compared to the combined influence of geographical isolation and land use intensification. These results indicate that environmental changes in riparian habitats have the potential to amplify shifts in the composition of stream fish communities in poorly connected river stretches. Conservation and management strategies for fish populations should, therefore, focus on enhancing connectivity between river stretches and limit conversion of nearby land to arable or urban use to maintain current levels of biodiversity.
Nizzetto, Luca; Bussi, Gianbattista; Futter, Martyn N; Butterfield, Dan; Whitehead, Paul G
2016-08-10
The presence of microplastics (MPs) in the environment is a problem of growing concern. While research has focused on MP occurrence and impacts in the marine environment, very little is known about their release on land, storage in soils and sediments and transport by run-off and rivers. This study describes a first theoretical assessment of these processes. A mathematical model of catchment hydrology, soil erosion and sediment budgets was upgraded to enable description of MP fate. The Thames River in the UK was used as a case study. A general lack of data on MP emissions to soils and rivers and the mass of MPs in agricultural soils, limits the present work to serve as a purely theoretical, nevertheless rigorous, assessment that can be used to guide future monitoring and impact evaluations. The fundamental assumption on which modelling is based is that the same physical controls on soil erosion and natural sediment transport (for which model calibration and validation are possible), also control MP transport and storage. Depending on sub-catchment soil characteristics and precipitation patterns, approximately 16-38% of the heavier-than-water MPs hypothetically added to soils (e.g. through routine applications of sewage sludge) are predicted to be stored locally. In the stream, MPs < 0.2 mm are generally not retained, regardless of their density. Larger MPs with densities marginally higher than water can instead be retained in the sediment. It is, however, anticipated that high flow periods can remobilize this pool. Sediments of river sections experiencing low stream power are likely hotspots for deposition of MPs. Exposure and impact assessments should prioritize these environments.
Understanding high magnitude flood risk: evidence from the past
NASA Astrophysics Data System (ADS)
MacDonald, N.
2009-04-01
The average length of gauged river flow records in the UK is ~25 years, which presents a problem in determining flood risk for high-magnitude flood events. Severe floods have been recorded in many UK catchments during the past 10 years, increasing the uncertainty in conventional flood risk estimates based on river flow records. Current uncertainty in flood risk has implications for society (insurance costs), individuals (personal vulnerability) and water resource managers (flood/drought risk). An alternative approach is required which can improve current understanding of the flood frequency/magnitude relationship. Historical documentary accounts are now recognised as a valuable resource when considering the flood frequency/magnitude relationship, but little consideration has been given to the temporal and spatial distribution of these records. Building on previous research based on British rivers (urban centre): Ouse (York), Trent (Nottingham), Tay (Perth), Severn (Shrewsbury), Dee (Chester), Great Ouse (Cambridge), Sussex Ouse (Lewes), Thames (Oxford), Tweed (Kelso) and Tyne (Hexham), this work considers the spatial and temporal distribution of historical flooding. The selected sites provide a network covering many of the largest river catchments in Britain, based on urban centres with long detailed documentary flood histories. The chronologies offer an opportunity to assess long-term patterns of flooding, indirectly determining periods of climatic variability and potentially increased geomorphic activity. This research represents the first coherent large scale analysis undertaken of historical multi-catchment flood chronologies, providing an unparalleled network of sites, permitting analysis of the spatial and temporal distribution of historical flood patterns on a national scale.
Lessons for climate policy from The Great Stink of London
NASA Astrophysics Data System (ADS)
Skuce, A.
2012-12-01
A rapidly growing population and the introduction of the flush toilet in nineteenth-century London caused a crisis with sewage pollution in the River Thames (Halliday, 1999). There were decades of delays in implementing solutions owing to: inadequate governance institutions; political inertia; difficulties with financing; opposition from vested interests; scientific uncertainties; and technological challenges. Effective counter-measures were started only once the problem arose, quite literally, under the noses of parliamentarians. There are parallels, some of them pointed out earlier by Alley et al (2010), between the sewage crisis in Victorian London and the current problem with climate change. Both involve the unsustainable use of a common resource (a river, the atmosphere) for the unconstrained disposal of human waste products. Alley (2011) estimated that the costs of providing clean water and sanitation are comparable to the expected costs of reducing greenhouse gas emissions. Despite the similarities, the climate change issue is actually much more difficult because of: a) the unequal and uncertain global distribution of cause and effect; b) its long, intergenerational time lines; c) the insufficiency of adequate institutions, conventions or the tools— political, moral or economic—for tackling the climate crisis. This analysis is consistent with the model proposed by Gardiner (2011) in his book A Perfect Moral Storm. The three "storms" he identifies, the global, intergenerational and theoretical storms, combine in a powerful synergy to create a challenge of unprecedented intractability, providing opportunities for what Gardiner calls moral corruption: the obscuring of the buck-passing and procrastination that characterizes climate policy today. In Victorian London, the crucial steps to solve the sewage crises were not taken until the stench from the River Thames during the hot summer of 1858 rendered the House of Commons uninhabitable. A greater stink of a different kind may have to be raised in the world's capitals before effective action begins on the much more challenging problem of climate change. References Alley, R. B., Haines-Stiles, G., Akuginow, E., 2010. Toilets and the Smart Grid: A role for history and art in communicating assessed science for Earth—The Operators' Manual. AGU, Fall Meeting 2010, abstract #ED41D-05. Alley, R.B., 2011. EARTH: The Operators' Manual. W.W. Norton & Company. ISBN 978-0-393-08109-1 Gardiner, S.H., 2011. A Perfect Moral Storm: The Ethical Tragedy of Climate Change. Oxford University Press. ISBN13: 9780195379440 Halliday, S. 1999. The Great Stink of London: Sir Joseph Bazalgette and the Cleansing of the Victorian Capital. Sutton Publishing Limited. ISBN 0-7509-1975-2
NASA Astrophysics Data System (ADS)
Bloomfield, J. P.; Allen, D. J.; Griffiths, K. J.
2009-06-01
SummaryLinear regression methods can be used to quantify geological controls on baseflow index (BFI). This is illustrated using an example from the Thames Basin, UK. Two approaches have been adopted. The areal extents of geological classes based on lithostratigraphic and hydrogeological classification schemes have been correlated with BFI for 44 'natural' catchments from the Thames Basin. When regression models are built using lithostratigraphic classes that include a constant term then the model is shown to have some physical meaning and the relative influence of the different geological classes on BFI can be quantified. For example, the regression constants for two such models, 0.64 and 0.69, are consistent with the mean observed BFI (0.65) for the Thames Basin, and the signs and relative magnitudes of the regression coefficients for each of the lithostratigraphic classes are consistent with the hydrogeology of the Basin. In addition, regression coefficients for the lithostratigraphic classes scale linearly with estimates of log 10 hydraulic conductivity for each lithological class. When a regression is built using a hydrogeological classification scheme with no constant term, the model does not have any physical meaning, but it has a relatively high adjusted R2 value and because of the continuous coverage of the hydrogeological classification scheme, the model can be used for predictive purposes. A model calibrated on the 44 'natural' catchments and using four hydrogeological classes (low-permeability surficial deposits, consolidated aquitards, fractured aquifers and intergranular aquifers) is shown to perform as well as a model based on a hydrology of soil types (BFIHOST) scheme in predicting BFI in the Thames Basin. Validation of this model using 110 other 'variably impacted' catchments in the Basin shows that there is a correlation between modelled and observed BFI. Where the observed BFI is significantly higher than modelled BFI the deviations can be explained by an exogenous factor, catchment urban area. It is inferred that this is may be due influences from sewage discharge, mains leakage, and leakage from septic tanks.
NASA Astrophysics Data System (ADS)
Hitt, O.; Hutchins, M.
2016-12-01
UK river waters face considerable future pressures, primarily from population growth and climate change. In understanding controls on river water quality, experimental studies have successfully identified response to single or paired stressors under controlled conditions. Generalised Linear Model (GLM) approaches are commonly used to quantify stressor-response relationships. To explore a wider variety of stressors physics-based models are used. Our objective is to evaluate how five different types of stressor influence the severity of river eutrophication and its impact on Dissolved Oxygen (DO) an integrated measure of river ecological health. This is done by applying a physics-based river quality model for 4 years at daily time step to a 92 km stretch in the 3445 km2 Thames (UK) catchment. To understand the impact of model structural uncertainty we present results from two alternative formulations of the biological response. Sensitivity analysis carried out using the QUESTOR model (QUality Evaluation and Simulation TOol for River systems) considered gradients of various stressors: river flow, water temperature, urbanisation (abstractions and sewage/industrial effluents), phosphate concentrations in effluents and tributaries and riparian tree shading (modifying the light input). Scalar modifiers applied to the 2009-12 time-series inputs define the gradients. The model has been run for each combination of the values of these 5 variables. Results are analysed using graphical methods in order to identify variation in the type of relationship between different pairs of stressors on the system response. The method allows for all outputs from each combination of stressors to be displayed in one graphic and so showing the results of hundreds of model runs simultaneously. This approach can be carried out for all stressor pairs, and many locations/determinands. Supporting statistical analysis (GLM) reinforces the findings from the graphical analysis. Analysis suggests that climate-driven variables (flow and river temperature) give strong explanation of variation in DO content. An indicator of low DO values typically seen in summer is chosen (10th percentile). Increasing temperature clearly has adverse effects lowering DO, and is illustrated in three example graphics.
NASA Astrophysics Data System (ADS)
Neumann, Jessica; Arnal, Louise; Magnusson, Linus; Cloke, Hannah
2017-04-01
Seasonal river flow forecasts are important for many aspects of the water sector including flood forecasting, water supply, hydropower generation and navigation. In addition to short term predictions, seasonal forecasts have the potential to realise higher benefits through more optimal and consistent decisions. Their operational use however, remains a challenge due to uncertainties posed by the initial hydrologic conditions (e.g. soil moisture, groundwater levels) and seasonal climate forcings (mainly forecasts of precipitation and temperature), leading to a decrease in skill with increasing lead times. Here we present a stakeholder-led case study for the Thames catchment (UK), currently being undertaken as part of the H2020 IMPREX project. The winter of 2013-14 was the wettest on record in the UK; driven by 12 major Atlantic depressions, the Thames catchment was subject to compound (concurrent) flooding from fluvial and groundwater sources. Focusing on the 2013-14 floods, this study aims to see whether increased skill in meteorological input translates through to more accurate forecasting of compound flood events at seasonal timescales in the Thames catchment. An earlier analysis of the ECMWF System 4 (S4) seasonal meteorological forecasts revealed that it did not skilfully forecast the extreme event of winter 2013-14. This motivated the implementation of an atmospheric experiment by the ECMWF to force the S4 to more accurately represent the low-pressure weather conditions prevailing in winter 2013-14 [1]. Here, we used both the standard and the "improved" S4 seasonal meteorological forecasts to force the EFAS (European Flood Awareness System) LISFLOOD hydrological model. Both hydrological forecasts were started on the 1st of November 2013 and run for 4 months of lead time to capture the peak of the 2013-14 flood event. Comparing the seasonal hydrological forecasts produced with both meteorological forcing data will enable us to assess how the improved meteorology translates into skill in the hydrological forecast for this extreme compound event. As primary stakeholders involved in the study, the Environment Agency and Flood Forecasting Centre are responsible for managing flood risk in the UK. For them, the detection of a potential flood signal weeks or months in advance could be of great value in terms of operational practice, decision-making and early warning. [1] Rodwell, M.J., Ferranti, L., Magnusson, L., Weisheimer, A., Rabier, F. & Richardson, D. (2015) Diagnosis of northern hemispheric regime behaviour during winter 2013/14. ECMWF Technical Memoranda 769.
Patterns, rates and possible causes of saltmarsh erosion in the Greater Thames area (UK)
NASA Astrophysics Data System (ADS)
van der Wal, Daphne; Pye, Kenneth
2004-08-01
The estuary-dominated coast of the Greater Thames in England has experienced rapid lateral erosion and internal dissection of saltmarshes. This paper provides an overview of saltmarsh development in this area, and re-examines the role of environmental and human forcing factors. It draws on documentary evidence, including historical maps, survey data and time-series data of forcing factors. Lateral marsh retreat began in the 19th century in the Medway and Blackwater Estuaries, followed by other estuaries in the Greater Thames region at the beginning of the 20th century. The outer estuaries and the wider parts of the inner estuaries especially have experienced erosion. Erosion has been modest in wave-sheltered areas, e.g., the Colne and the inner Crouch. In the 1960s and, more widely, the 1970s, a phase of rapid erosion took place, with erosion rates of up to ca. 16 ha year -1 per site, notably along the open coast of Dengie and Foulness, and in the Blackwater and Thames Estuaries. At all sites, vertical sediment accretion was well able to keep up with sea level rise over the past century. Evidence indicates that there may have been several causes for the erosion of saltmarshes. These are notably land claim and embankment construction (increasing the tidal range and current velocities) and a continuous rise of, especially, high and extreme water levels. The latest episode of rapid erosion in the 1970s is largely attributed to changes in the wind/wave climate. For example, erosion at wave-exposed sites coincided with a peak in high magnitude waves combined with a high incidence of southeasterly waves. The study shows that many factors, including natural forcing factors and human activities, have to be taken into account when explaining saltmarsh development.
Consumer involvement in cancer research: example from a Cancer Network.
Arain, Mubashir; Pyne, Sarah; Thornton, Nigel; Palmer, Susan; Sharma, Ricky A
2015-10-01
The involvement of consumers and the general public in improving cancer services is an important component of health services. However, consumer involvement in cancer research is relatively unexplored. The objective of this study was to explore different ways of involving consumers in cancer research in one regional network. Thames Valley Cancer Network Consumer Research Partnership (CRP) group was formed in 2009. The group consists of consumers and professionals to help in promoting consumer involvement in Cancer Research in the Thames Valley. This study evaluated the project of consumer involvement in cancer research in the Thames Valley from March 2010 to March 2011. We used different indices to judge the level of consumer involvement: number of projects involving consumers through the group, types of projects, level of involvement (ranged from consultation on research documents to collaborating in preparing grant applications) and the methods of involving consumers in cancer research. Fifteen projects were submitted to the CRP group during the 12-month period studied. Of these, eight projects were clinical trials, three were qualitative research projects, two were patients' surveys and two were non-randomized interventional studies. Seven projects requested consumer involvement on patient information sheets for clinical trials. Of these seven applications, three also requested consumers' help in designing research questionnaires and another three requested that consumers should be involved in their project management group. In addition, four projects involved consumers in the proposal development phase and another four projects asked for advice on how to increase trial recruitment, conduct patient interviews or help with grant applications. The creation of the CRP and this audit of its activity have documented consumer involvement in cancer research in the Thames Valley. We have clearly shown that consumers can be involved in designing and managing cancer research projects. © 2013 John Wiley & Sons Ltd.
Nitrogen sources, transport and processing in peri-urban floodplains.
Gooddy, D C; Macdonald, D M J; Lapworth, D J; Bennett, S A; Griffiths, K J
2014-10-01
Peri-urban floodplains are an important interface between developed land and the aquatic environment and may act as a source or sink for contaminants moving from urban areas towards surface water courses. With increasing pressure from urban development the functioning of floodplains is coming under greater scrutiny. A number of peri-urban sites have been found to be populated with legacy landfills which could potentially cause pollution of adjacent river bodies. Here, a peri-urban floodplain adjoining the city of Oxford, UK, with the River Thames has been investigated over a period of three years through repeated sampling of groundwaters from existing and specially constructed piezometers. A nearby landfill has been found to have imprinted a strong signal on the groundwater with particularly high concentrations of ammonium and generally low concentrations of nitrate and dissolved oxygen. An intensive study of nitrogen dynamics through the use of N-species chemistry, nitrogen isotopes and dissolved nitrous oxide reveals that there is little or no denitrification in the majority of the main landfill plume, and neither is the ammonium significantly retarded by sorption to the aquifer sediments. A simple model has determined the flux of total nitrogen and ammonium from the landfill, through the floodplain and into the river. Over an 8 km reach of the river, which has a number of other legacy landfills, it is estimated that 27.5 tonnes of ammonium may be delivered to the river annually. Although this is a relatively small contribution to the total river nitrogen, it may represent up to 15% of the ammonium loading at the study site and over the length of the reach could increase in-stream concentrations by nearly 40%. Catchment management plans that encompass floodplains in the peri-urban environment need to take into account the likely risk to groundwater and surface water quality that these environments pose. Crown Copyright © 2014. Published by Elsevier B.V. All rights reserved.
INCA Modelling of the Lee System: strategies for the reduction of nitrogen loads
NASA Astrophysics Data System (ADS)
Flynn, N. J.; Paddison, T.; Whitehead, P. G.
The Integrated Nitrogen Catchment model (INCA) was applied successfully to simulate nitrogen concentrations in the River Lee, a northern tributary of the River Thames for 1995-1999. Leaching from urban and agricultural areas was found to control nitrogen dynamics in reaches unaffected by effluent discharges and abstractions; the occurrence of minimal flows resulted in an upward trend in nitrate concentration. Sewage treatment works (STW) discharging into the River Lee raised nitrate concentrations substantially, a problem which was compounded by abstractions in the Lower Lee. The average concentration of nitrate (NO3) for the simulation period 1995-96 was 7.87 mg N l-1. Ammonium (NH4) concentrations were simulated less successfully. However, concentrations of ammonium rarely rose to levels which would be of environmental concern. Scenarios were run through INCA to assess strategies for the reduction of nitrate concentrations in the catchment. The conversion of arable land to ungrazed vegetation or to woodland would reduce nitrate concentrations substantially, whilst inclusion of riparian buffer strips would be unsuccessful in reducing nitrate loading. A 50% reduction in nitrate loading from Luton STW would result in a fall of up to 5 mg N l-1 in the reach directly affected (concentrations fell from maxima of 13 to 8 mg N l-1 , nearly a 40 % reduction), whilst a 20% reduction in abstractions would reduce maximum peaks in concentration in the lower Lee by up to 4 mg l-1 (from 17 to 13 mg N l-1, nearly a 25 % reduction),.
Moorhouse, Tom P; Poole, Alison E; Evans, Laura C; Bradley, David C; Macdonald, David W
2014-02-01
Invasive species are a major cause of species extinction in freshwater ecosystems, and crayfish species are particularly pervasive. The invasive American signal crayfish Pacifastacus leniusculus has impacts over a range of trophic levels, but particularly on benthic aquatic macroinvertebrates. Our study examined the effect on the macroinvertebrate community of removal trapping of signal crayfish from UK rivers. Crayfish were intensively trapped and removed from two tributaries of the River Thames to test the hypothesis that lowering signal crayfish densities would result in increases in macroinvertebrate numbers and taxon richness. We removed 6181 crayfish over four sessions, resulting in crayfish densities that decreased toward the center of the removal sections. Conversely in control sections (where crayfish were trapped and returned), crayfish density increased toward the center of the section. Macroinvertebrate numbers and taxon richness were inversely correlated with crayfish densities. Multivariate analysis of the abundance of each taxon yielded similar results and indicated that crayfish removals had positive impacts on macroinvertebrate numbers and taxon richness but did not alter the composition of the wider macroinvertebrate community. Synthesis and applications: Our results demonstrate that non-eradication-oriented crayfish removal programmes may lead to increases in the total number of macroinvertebrates living in the benthos. This represents the first evidence that removing signal crayfish from riparian systems, at intensities feasible during control attempts or commercial crayfishing, may be beneficial for a range of sympatric aquatic macroinvertebrates.
Moorhouse, Tom P; Poole, Alison E; Evans, Laura C; Bradley, David C; Macdonald, David W
2014-01-01
Invasive species are a major cause of species extinction in freshwater ecosystems, and crayfish species are particularly pervasive. The invasive American signal crayfish Pacifastacus leniusculus has impacts over a range of trophic levels, but particularly on benthic aquatic macroinvertebrates. Our study examined the effect on the macroinvertebrate community of removal trapping of signal crayfish from UK rivers. Crayfish were intensively trapped and removed from two tributaries of the River Thames to test the hypothesis that lowering signal crayfish densities would result in increases in macroinvertebrate numbers and taxon richness. We removed 6181 crayfish over four sessions, resulting in crayfish densities that decreased toward the center of the removal sections. Conversely in control sections (where crayfish were trapped and returned), crayfish density increased toward the center of the section. Macroinvertebrate numbers and taxon richness were inversely correlated with crayfish densities. Multivariate analysis of the abundance of each taxon yielded similar results and indicated that crayfish removals had positive impacts on macroinvertebrate numbers and taxon richness but did not alter the composition of the wider macroinvertebrate community. Synthesis and applications: Our results demonstrate that non-eradication-oriented crayfish removal programmes may lead to increases in the total number of macroinvertebrates living in the benthos. This represents the first evidence that removing signal crayfish from riparian systems, at intensities feasible during control attempts or commercial crayfishing, may be beneficial for a range of sympatric aquatic macroinvertebrates. PMID:24634733
St. Petersburg, Russia as seen from STS-60
1994-02-09
STS060-103-055 (3-11 Feb 1994) --- This wintertime photograph shows the large city of St. Petersburg Russia at the head of the Gulf of Finland. The city, built by Peter the Great, is situated in the former swampy delta of the Neva River which connects the large Lake Ladoga (the frozen white surface on the edge of the photograph) to the Gulf of Finland. An interesting feature of St. Petersburg which can be discerned in this photograph is the new storm surge barrier built from both sides of the Gulf of Finland out to the island of Kronstadt in the middle. This barrier, similar to that which was built on the Thames River south of London to protect it from storm surges out of the North Sea, was constructed to protect St. Petersburg from storm surges coming out of the Baltic Sea and being magnified by the topography and hydrography of the Gulf of Finland. Also visible as a thin line between Kronstadt and St. Petersburg is the ice-free shipping channel kept open much of the winter. Power plant plumes are also visible on the frame. St. Petersburg is the home of the Russian cosmonaut, Sergei Krikalev, who flew aboard the Space Shuttle Discovery during STS-60.
Assessing the Ecotoxicologic Hazards of a Pandemic Influenza Medical Response
Colizza, Vittoria; Schmitt, Heike; Andrews, Johanna; Balcan, Duygu; Huang, Wei E.; Keller, Virginie D.J.; Vespignani, Alessandro; Williams, Richard J.
2011-01-01
Background: The global public health community has closely monitored the unfolding of the 2009 H1N1 influenza pandemic to best mitigate its impact on society. However, little attention has been given to the impact of this response on the environment. Antivirals and antibiotics prescribed to treat influenza are excreted into wastewater in a biologically active form, which presents a new and potentially significant ecotoxicologic challenge to microorganisms responsible for wastewater nutrient removal in wastewater treatment plants (WWTPs) and receiving rivers. Objectives: We assessed the ecotoxicologic risks of a pandemic influenza medical response. Methods: To evaluate this risk, we coupled a global spatially structured epidemic model that simulates the quantities of antivirals and antibiotics used during an influenza pandemic of varying severity and a water quality model applied to the Thames catchment to determine predicted environmental concentrations. An additional model was then used to assess the effects of antibiotics on microorganisms in WWTPs and rivers. Results: Consistent with expectations, our model projected a mild pandemic to exhibit a negligible ecotoxicologic hazard. In a moderate and severe pandemic, we projected WWTP toxicity to vary between 0–14% and 5–32% potentially affected fraction (PAF), respectively, and river toxicity to vary between 0–14% and 0–30% PAF, respectively, where PAF is the fraction of microbial species predicted to be growth inhibited (lower and upper 95% reference range). Conclusions: The current medical response to pandemic influenza might result in the discharge of insufficiently treated wastewater into receiving rivers, thereby increasing the risk of eutrophication and contamination of drinking water abstraction points. Widespread drugs in the environment could hasten the generation of drug resistance. Our results highlight the need for empirical data on the effects of antibiotics and antiviral medications on WWTPs and freshwater ecotoxicity. PMID:21367688
Assessing the ecotoxicologic hazards of a pandemic influenza medical response.
Singer, Andrew C; Colizza, Vittoria; Schmitt, Heike; Andrews, Johanna; Balcan, Duygu; Huang, Wei E; Keller, Virginie D J; Vespignani, Alessandro; Williams, Richard J
2011-08-01
The global public health community has closely monitored the unfolding of the 2009 H1N1 influenza pandemic to best mitigate its impact on society. However, little attention has been given to the impact of this response on the environment. Antivirals and antibiotics prescribed to treat influenza are excreted into wastewater in a biologically active form, which presents a new and potentially significant ecotoxicologic challenge to microorganisms responsible for wastewater nutrient removal in wastewater treatment plants (WWTPs) and receiving rivers. We assessed the ecotoxicologic risks of a pandemic influenza medical response. To evaluate this risk, we coupled a global spatially structured epidemic model that simulates the quantities of antivirals and antibiotics used during an influenza pandemic of varying severity and a water quality model applied to the Thames catchment to determine predicted environmental concentrations. An additional model was then used to assess the effects of antibiotics on microorganisms in WWTPs and rivers. Consistent with expectations, our model projected a mild pandemic to exhibit a negligible ecotoxicologic hazard. In a moderate and severe pandemic, we projected WWTP toxicity to vary between 0-14% and 5-32% potentially affected fraction (PAF), respectively, and river toxicity to vary between 0-14% and 0-30% PAF, respectively, where PAF is the fraction of microbial species predicted to be growth inhibited (lower and upper 95% reference range). The current medical response to pandemic influenza might result in the discharge of insufficiently treated wastewater into receiving rivers, thereby increasing the risk of eutrophication and contamination of drinking water abstraction points. Widespread drugs in the environment could hasten the generation of drug resistance. Our results highlight the need for empirical data on the effects of antibiotics and antiviral medications on WWTPs and freshwater ecotoxicity.
Flooding and subsidence in the Thames Gateway: impact on insurance loss potential
NASA Astrophysics Data System (ADS)
Royse, Katherine; Horn, Diane; Eldridge, Jillian; Barker, Karen
2010-05-01
In the UK, household buildings insurance generally covers loss and damage to the insured property from a range of natural and human perils, including windstorm, flood, subsidence, theft, accidental fire and winter freeze. Consequently, insurers require a reasoned view on the likely scale of losses that they may face to assist in strategic planning, reinsurance structuring, regulatory returns and general risk management. The UK summer 2007 flood events not only provided a clear indication of the scale of potential losses that the industry could face from an individual event, with £3 billion in claims, but also identified a need for insurers and reinsurers to better understand how events may correlate in time and space, and how to most effectively use the computational models of extreme events that are commonly applied to reflect these correlations. In addition to the potential for temporal clustering of events such as windstorms and floods, there is a possibility that seemingly uncorrelated natural perils, such as floods and subsidence, may impact an insurer's portfolio. Where aggregations of large numbers of new properties are planned, such as in the Thames Gateway, consideration of the potential future risk of aggregate losses due to the combination of perils such as subsidence and flood is increasingly important within the insurance company's strategic risk management process. Whilst perils such as subsidence and flooding are generally considered independent within risk modelling, the potential for one event to influence the magnitude and likelihood of the other should be taken into account when determining risk level. In addition, the impact of correlated, but distinctive, loss causing events on particular property types may be significant, particularly if a specific property is designed to protect against one peril but is potentially susceptible to another. We suggest that flood events can lead to increased subsidence risk due to the weight of additional water and sediment, or rehydration of sediment under flood water. The latter mechanism may be particularly critical on sites where Holocene sediments are currently protected from flooding and are no longer subsiding. Holocene deposits tend to compress, either under their own weight or under a superimposed load such as made ground, built structures or flood water. If protected dry sediments become flooded in the future, subsidence would be expected to resume. This research project aims to investigate the correlation between flood hazards and subsidence hazards and the effect that these two sources of risk will have on insurance losses in the Thames Gateway. In particular, the research will explore the potential hydrological and geophysical drivers and links between flood and subsidence events within the Thames Gateway, assessing the potential for significant event occurrence within the timescales relevant to insurers. In the first part of the project we have identified flood risk areas within the Thames Gateway development zone which have a high risk of flooding and may be affected by renewed or increased subsidence. This has been achieved through the use of national and local-scale 2D and 3D geo-environmental information such as the Geosure dataset (e.g. swell-shrink, collapsible and compressible deposits data layers), PSI data, thickness of superficial and artificial land deposits, and flood potential data etc. In the second stage of the project we will investigate the hydrological and geophysical links between flooding and subsidence events on developed sites; quantify the insurance loss potential in the Thames Gateway from correlated flooding and subsidence events; consider how climate change will affect risk to developments in the Thames Gateway in the context of subsidence and flooding; and develop new ways of communicating and visualise correlated flood and subsidence risk to a range of stakeholders, including the insurance industry, planners, policy makers and the general public.
A 125 year long record of DOC flux from a major temperate catchment: land-use vs. climate control?
NASA Astrophysics Data System (ADS)
Clay, G.; Worrall, F.; Howden, N. K.; Burt, T. P.
2010-12-01
Our understanding of the controls upon carbon biogeochemistry has always been limited by lack of long term observational data at the same time as having long term monitoring of possible environmental drivers. For the River Thames catchment in the UK (9998 km2) records of DOM have been kept since 1868 and DOM flux since 1882. In addition to riverflow being monitored in the catchment there has also been monitoring of climate, land-use and population back to at least 1868. The Thames catchment is a mixed agricultural urban catchment dominated by mineral soils where groundwater plays a significant part in the catchments flow system. During the period of the record the catchment has undergone urbanisation, climate warming but has also undergone large-scale land use change associated with World War II and agricultural intensification in the 1960s. The importance of these combinations of pressures are explored in the time series through a range of time series techniques and the results show: i) That DOC flux in the catchment is now at historic low levels, with the maximum flux being 35 ktonnes C/yr (3.5 tonnes/km2/yr) in 1915 and the lowest flux being 2 ktonnes C/yr (0.2 tonnes/km2/yr) in 1997. ii) The trend in the DOC flux is explained by changes in flow, which appear associated with both with groundwater storage in the catchment and with changes in land-use. iii) The significant decline in the DOC flux appears to be due to the transition in the catchment from dominated from pasture to an arable land use. iv) The decline of DOC flux with temperature would suggest that DOC mineralisation reaction has a higher Q10 than the DOC production. v) Declining DOC flux from mineral soils catchments would offset increases in DOC flux from organic soils but would also represent a shift in carbon losses from fluvial to being direct to the atmosphere.
Singer, Andrew C.; Järhult, Josef D.; Grabic, Roman; Khan, Ghazanfar A.; Lindberg, Richard H.; Fedorova, Ganna; Fick, Jerker; Bowes, Michael J.; Olsen, Björn; Söderström, Hanna
2014-01-01
The concentration of eleven antibiotics (trimethoprim, oxytetracycline, ciprofloxacin, azithromycin, cefotaxime, doxycycline, sulfamethoxazole, erythromycin, clarithromycin, ofloxacin, norfloxacin), three decongestants (naphazoline, oxymetazoline, xylometazoline) and the antiviral drug oseltamivir’s active metabolite, oseltamivir carboxylate (OC), were measured weekly at 21 locations within the River Thames catchment in England during the month of November 2009, the autumnal peak of the influenza A[H1N1]pdm09 pandemic. The aim was to quantify the pharmaceutical response to the pandemic and compare this to drug use during the late pandemic (March 2010) and the inter-pandemic periods (May 2011). A large and small wastewater treatment plant (WWTP) were sampled in November 2009 to understand the differential fate of the analytes in the two WWTPs prior to their entry in the receiving river and to estimate drug users using a wastewater epidemiology approach. Mean hourly OC concentrations in the small and large WWTP’s influent were 208 and 350 ng/L (max, 2070 and 550 ng/L, respectively). Erythromycin was the most concentrated antibiotic measured in Benson and Oxford WWTPs influent (max = 6,870 and 2,930 ng/L, respectively). Napthazoline and oxymetazoline were the most frequently detected and concentrated decongestant in the Benson WWTP influent (1650 and 67 ng/L) and effluent (696 and 307 ng/L), respectively, but were below detection in the Oxford WWTP. OC was found in 73% of November 2009’s weekly river samples (max = 193 ng/L), but only in 5% and 0% of the late- and inter-pandemic river samples, respectively. The mean river concentration of each antibiotic during the pandemic largely fell between 17–74 ng/L, with clarithromycin (max = 292 ng/L) and erythromycin (max = 448 ng/L) yielding the highest single measure. In general, the concentration and frequency of detecting antibiotics in the river increased during the pandemic. OC was uniquely well-suited for the wastewater epidemiology approach owing to its nature as a prodrug, recalcitrance and temporally- and spatially-resolved prescription statistics. PMID:25254643
Scheduling Future Water Supply Investments Under Uncertainty
NASA Astrophysics Data System (ADS)
Huskova, I.; Matrosov, E. S.; Harou, J. J.; Kasprzyk, J. R.; Reed, P. M.
2014-12-01
Uncertain hydrological impacts of climate change, population growth and institutional changes pose a major challenge to planning of water supply systems. Planners seek optimal portfolios of supply and demand management schemes but also when to activate assets whilst considering many system goals and plausible futures. Incorporation of scheduling into the planning under uncertainty problem strongly increases its complexity. We investigate some approaches to scheduling with many-objective heuristic search. We apply a multi-scenario many-objective scheduling approach to the Thames River basin water supply system planning problem in the UK. Decisions include which new supply and demand schemes to implement, at what capacity and when. The impact of different system uncertainties on scheme implementation schedules are explored, i.e. how the choice of future scenarios affects the search process and its outcomes. The activation of schemes is influenced by the occurrence of extreme hydrological events in the ensemble of plausible scenarios and other factors. The approach and results are compared with a previous study where only the portfolio problem is addressed (without scheduling).
Greenhouse gas emissions of waste management processes and options: A case study.
de la Barrera, Belen; Hooda, Peter S
2016-07-01
Increasing concern about climate change is prompting organisations to mitigate their greenhouse gas emissions. Waste management activities also contribute to greenhouse gas emissions. In the waste management sector, there has been an increasing diversion of waste sent to landfill, with much emphasis on recycling and reuse to prevent emissions. This study evaluates the carbon footprint of the different processes involved in waste management systems, considering the entire waste management stream. Waste management data from the Royal Borough of Kingston upon Thames, London (UK), was used to estimate the carbon footprint for its (Royal Borough of Kingston upon Thames) current source segregation system. Second, modelled full and partial co-mingling scenarios were used to estimate carbon emissions from these proposed waste management approaches. The greenhouse gas emissions from the entire waste management system at Royal Borough of Kingston upon Thames were 12,347 t CO2e for the source-segregated scenario, and 11,907 t CO2e for the partial co-mingled model. These emissions amount to 203.26 kg CO2e t(-1) and 196.02 kg CO2e t(-1) municipal solid waste for source-segregated and partial co-mingled, respectively. The change from a source segregation fleet to a partial co-mingling fleet reduced the emissions, at least partly owing to a change in the number and type of vehicles. © The Author(s) 2016.
Gallardo, Belinda; Aldridge, David C
2013-03-01
Invasive species drive important ecological and economic losses across wide geographies, with some regions supporting especially large numbers of nonnative species and consequently suffering relatively high impacts. For this reason, integrated risk assessments able to screen a suite of multiple invaders over large geographic areas are needed for prioritizing the allocation of limited resources. A total of 16 Ponto-Caspian aquatic species (10 gammarids, one isopod, two mysids, and three fishes) have been short-listed as recent or potential future invaders of British waters, whose introduction and spread is of high concern. In this study, we use multiple modeling techniques to assess their risk of establishment and spread into Great Britain. Climate suitability maps for these 16 species differed depending on the eastern and western distribution of species in continental Europe, which was related to their respective migration corridor: southern (Danube-Rhine rivers), and northern (Don and Volga rivers and Baltic lakes). Species whose suitability was high across large parts of Great Britain included four gammarids (Cheliorophium robustum, Dikerogammarus bispinosus, D. villosus, and Echinogammarus trichiatus) and a mysid (Hemimysis anomala). A climatic "heat map" combining the results of all 16 species together pointed to the southeast of England as the area most vulnerable to multiple invasions, particularly the Thames, Anglian, Severn, and Humber river basin districts. Regression models further suggested that alkalinity concentration > 120 mg/L in southeast England may favor the establishment of Ponto-Caspian invaders. The production of integrated risk maps for future invaders provides a means for the scientifically informed prioritization of resources toward particular species and geographic regions. Such tools have great utility in helping environmental managers focus efforts on the most effective prevention, management, and monitoring programs.
15. Foreground; broken gear from headhouse of electric powered Marine ...
15. Foreground; broken gear from headhouse of electric powered Marine Railway #3; cradle for Marine Railway #3 in background. - Thames Tow Boat Company, Foot of Farnsworth Street, New London, New London County, CT
13. Steam powered Marine Railway Headhouse and Offices, center; chain ...
13. Steam powered Marine Railway Headhouse and Offices, center; chain is in front of electric powered Marine Railway Headhouse. - Thames Tow Boat Company, Foot of Farnsworth Street, New London, New London County, CT
What are the governing processes during low-flows in a chalk catchment?
NASA Astrophysics Data System (ADS)
Lubega Musuuza, Jude; Coxon, Gemma; Hutton, Chris; Howden, Nicholas; Woods, Ross; Freer, Jim; Wagener, Thorsten
2016-04-01
Low flows are important because they lead to the prioritisation of different consumptive water usages, imposition of restrictions and bans, raising of water tariffs and higher production costs to industry. The partitioning of precipitation into evaporation, storage and runoff depends on the local variability in meteorological variables and site-specific characteristics e.g., topography, soils and vegetation. The response of chalk catchments to meteorological forcing especially precipitation is of particular interest because of the preferential flow through the weathered formation. This makes the observed stream discharge groundwater-dominated and hence, out of phase with precipitation. One relevant question is how sensitive the low flow characteristics of such a chalk catchment is to changes in climate and land use. It is thus important to understand all the factors that control low stream discharge periods. In this study we present the results from numerical sensitivity analysis experiments performed with a detailed physically-based model on the Kennet, a sub-catchment of the River Thames, in the UK during the historical drought years of the 1970's.
18. Marine Railway #1, location in foreground; Marine Railway #2 ...
18. Marine Railway #1, location in foreground; Marine Railway #2 (broken cradle) center; cradle for Marine Railway #3 on right. - Thames Tow Boat Company, Foot of Farnsworth Street, New London, New London County, CT
Modeling the stratigraphy and preservation potential of meandering stream deposits
NASA Astrophysics Data System (ADS)
Tucker, G. E.; Clevis, Q.; Lock, G.; Lancaster, S.; Desitter, A.
2003-12-01
Both natural and human-induced modes of river and floodplain behavior have the potential to obscure, expose, or even destroy portions of the archaeological record. In valley systems with actively meandering channels much material can be lost to lateral bank erosion. Conversely, floodplain aggradation can bury and therefore obscure sites. In this study we aim to quantify the preservation potential of fluvial units containing archaeological sites as a function of the natural process of meandering, climate change and increased land-use during the Holocene. We used the CHILD simulation model of landscape evolution to explore alternative scenarios in which these three factors are both varied independently and combined. Boundary and initial conditions for the model scenarios are based on the Holocene evolution of the archaeologically-rich Upper Thames Valley, which is known to have witnessed variations in flood frequency, land-clearance, episodic alluviation and river entrenchment. The CHILD model is set up to combine four components that simulate the development of valley and floodplain system: hillslope and channel erosion, lateral stream meandering, overbank deposition, and the accumulation of a 3D stratigraphy. The landscape is represented by an adaptable triangular mesh of nodes, especially suited for simulating the gradual shifting of meander bends. The new stratigraphic layering routine recently added to the model in improves the resolution of the stratigraphic record accumulated by the model. Simulation results reveal systematic controls on preservation potential, and suggest potential sources of bias in the archaeological record.
Stuart, Marianne E; Lapworth, Dan J; Thomas, Jenny; Edwards, Laura
2014-01-15
Evaluating the occurrence of microorganics helps to understand sources and processes which may be controlling the transport and fate of emerging contaminants (ECs). A study was carried out at the contrasting instrumented environmental observatory sites at Oxford, on the peri-urban floodplain gravel aquifer of the River Thames and Boxford, in the rural valley of the River Lambourn on the chalk aquifer, in Southern England to explore the use of ECs to fingerprint contaminant sources and flow pathways in groundwater. At Oxford compounds were typical of a local waste tip plume (not only plasticisers and solvents but also barbiturates and N,N-diethyl-m-toluamide (DEET)) and of the urban area (plasticisers and mood-enhancing drugs such as carbamazepine). At Boxford the results were different with widespread occurrence of agricultural pesticides, their metabolites and the solvent trichloroethene, as well as plasticisers, caffeine, butylated food additives, DEET, parabens and trace polyaromatic hydrocarbons (PAHs). Groups of compounds used in pharmaceuticals and personal care products of different provenance in the environment could be distinguished, i) historical household and medical waste, ii) long-term household usage persistent in groundwater and iii) current usage and contamination from surface water. Co-contaminant and degradation products can also indicate the likely source of contaminants. A cocktail of contaminants can be used as tracers to provide information on catchment pathways and groundwater/surface water interactions. A prominent feature in this study is the attenuation of many EC compounds in the hyporheic zone. © 2013.
2003-01-18
For almost 2,000 years, the River Thames has served as the life force of London, capital of the United Kingdom and one of the world's most famous cities. In AD 43 the Romans established the trading settlement of Londinium at a favorable crossing point on the river. The Romans remained until the 5th century, when the city came under Saxon control. The early 17th century saw enormous growth, but the deadly plague of 1664 and 1665 ravaged the population, and in the following year the Great Fire, which burned for four days, destroyed most of the city. A public transportation system and other city services in the early 19th century eased many of the increasing urban problems of the burgeoning capital of the wealthy British Empire. After coping with the devastating effects of bombing during World War II and the gradual dismantling of the empire, London today thrives as a vital modern metropolis. London is one of 100 cities being studied using ASTER data to map and monitor urban use patterns and growth. This image was acquired on October 12, 2001 by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA's Terra satellite. With its 14 spectral bands from the visible to the thermal infrared wavelength region, and its high spatial resolution of 15 to 90 meters (about 50 to 300 feet), ASTER images Earth to map and monitor the changing surface of our planet. http://photojournal.jpl.nasa.gov/catalog/PIA04301
58. Detail of steam pistons and gears for driving winches ...
58. Detail of steam pistons and gears for driving winches to Marine Railways #1 and #2, Marine Railway Headhouse, ground floor, looking north. - Thames Tow Boat Company, Foot of Farnsworth Street, New London, New London County, CT
NASA Astrophysics Data System (ADS)
Hutchins, M.; McGrane, S. J.; Miller, J. D.; Hitt, O.; Bowes, M.
2016-12-01
Continuous monitoring of water flows and quality is invaluable in improving understanding of the influence of urban areas on river health. When used to inform predictive modelling, insights can be gained as to how urban growth may affect the chemical and biological quality of rivers as they flow downstream into larger waterbodies. Water flow and quality monitoring in two urbanising sub-catchments (<100 km2) of the River Thames (southern UK) is described. Temperature, conductivity, turbidity, dissolved oxygen (DO) and ammonium (NH4) were measured at downstream locations where long term flow records are available, but particular focus is given to monitoring of an extended set of sites during prolonged winter rainfall. In the Ray sub-catchment streams were monitored in which urban cover varied across a range of 7-78%. A rural-urban gradient in DO was apparent in the low flow period prior to the storms. Transient low DO (< 8 mg L-1) as a response to pollutant first flushes was particularly apparent in urban streams but this was followed by a rapid recovery. Chronic effects lasting for three to four weeks were only seen downstream of a sewage treatment works (STW). In this respect temperature- and respiration-driven DO sags in summer were at least if not more severe than those driven by the winter storms. Likewise, although winter storm NH4 concentrations violated EU legislation downstream of the STW, they were lower than summer concentrations in pollutant flushes following dry spells. In contrast the predominant phenomenon affecting water quality in the Cut during the storms was dilution. Here, a river water quality model was calibrated and applied over the course of a year to capture the importance of periphyton photosynthesis and respiration cycles in determining water quality and to predict the influence of hypothetical urban growth on downstream river health. The periods monitored intensively, dry spells followed by prolonged rainfall, represent: (i) marked changes in conditions likely to become more prevalent in future, (ii) situations under which water quality in urban areas is likely to be particularly vulnerable, being influenced for example by first flush effects followed by capacity exceedance at STW. Despite this, whilst being somewhat long lasting in places, impacts on DO were not severe.
'Botanic Man:' Education or Entertainment?
ERIC Educational Resources Information Center
Freeman, Richard
1979-01-01
The experience of Thames Television in presenting an educational series during prime time is described. "The Botanic Man," a series on ecology, is a rating success. Several difficulties encountered in collaboration efforts and follow-up activities, including courses and workbook publications, are identified. (JMF)
26. Detail showing piston which is one of two steam ...
26. Detail showing piston which is one of two steam powered drive units for winches for Marine Railways #1. and #2, Marine Railway Headhouse. - Thames Tow Boat Company, Foot of Farnsworth Street, New London, New London County, CT
17. From left to right: Marine Railway Headhouse and Offices, ...
17. From left to right: Marine Railway Headhouse and Offices, Boiler Room, first skylight, chimney for Boiler, Blacksmith Shop, second skylight, and Pipe, Paint, and Electrical Shops. - Thames Tow Boat Company, Foot of Farnsworth Street, New London, New London County, CT
NASA Astrophysics Data System (ADS)
Wade, Andrew; Palmer-Felgate, Elizabeth; Halliday, Sarah; Skeffington, Richard; Loewenthal, Matthew; Jarvie, Helen; Bowes, Michael; Greenway, Gillian; Haswell, Stephen; Bell, Ian; Joly, Etienne; Fallatah, Ahmed; Neal, Colin; Williams, Richard; Gozzard, Emma; Newman, Jonathan
2013-04-01
This work focuses on the insights obtained from in situ, high-resolution hydrochemical monitoring in three lowland UK catchments experiencing different levels of nutrient enrichment. Between November 2009 and February 2012, the upper River Kennet, the River Enborne and The Cut, all located within the Thames basin, southeast England, were instrumented with in situ analytical equipment to make hourly measurements of a range of hydrochemical determinands. The upper River Kennet is a rural catchment with limited effluent inputs above the selected monitoring point. The River Enborne is a rural catchment, impacted by agricultural runoff, and septic tank and sewage treatment works (STWs) discharges. The Cut is a highly urbanised system significantly affected by STW discharges. On the upper River Kennet and the River Enborne hourly measurements of Total Reactive Phosphorus (TRP) were made using a Systea Micromac C. In addition on the River Enborne, a Hach Lange Nitratax was used to measure nitrate (NO3). On The Cut both Total P and TRP were measured using a Hach Lange Phosphax Sigma. At all stations nutrient monitoring was supplemented with hourly pH, chlorophyll, dissolved oxygen, conductivity, turbidity and water temperature using YSI 6600 Multi-parameter sondes. Instream hydrochemical dynamics were investigated using non-stationary time-series analysis techniques. The results reveal complex nutrient dynamics, with diurnal patterns which exhibit seasonal changes in phase and amplitude, and are influenced by flow conditions, shading and nutrient sources. On the River Enborne a marked diurnal cycle was present within the streamwater NO3 time-series. The cycle was strongest in the spring before riparian shading developed. At times of low flow a two peak diurnal cycle was also evident in the streamwater NO3 time-series. The reduction in diurnal NO3 processing after the development of riparian shading was also accompanied by a marked drop in dissolved oxygen at this time. The presence of a two peak diurnal cycle is indicative of the dominance of STW discharges to the system, as STW discharges exhibit a marked two peak diurnal cycle associated with peak water usage. This two peak diurnal cycling can also been seen in the River Enborne TRP data. The dominance of effluent discharges was also evident in the River Enborne seasonal NO3 and TRP dynamics. Both determinands displayed summer time peaks caused by the reduced dilution capacity of the system and increased water residence time during the low flow summer months. The TP and TRP dynamics on The Cut were highly complex with significant diurnal fluctuations. Although, a two peak diurnal signal was evident within the TRP time-series it was difficult to characterise due to the complexity of the dynamics observed. Monitoring on the upper River Kennet highlighted the challenges associated with undertaking in situ analytical monitoring without mains electricity. Resampling of the data at lower sampling frequencies demonstrated that within the point-source dominated catchments, daily monitoring was sufficient for accurate load estimation.
Breast cancer management: is volume related to quality? Clinical Advisory Panel.
Ma, M; Bell, J; Campbell, S; Basnett, I; Pollock, A; Taylor, I
1997-01-01
A method of carrying out region-wide audit for breast cancer was developed by collaboration between the cancer registry, providers and purchasers as part of work to fulfill the 'Calman-Hine' recommendations. In order to test the audit method, a retrospective audit in North Thames East compared practice in 1992 against current guidelines. The analysis compared care in specialist and non-specialist centres. A stratified random sample comprising 28% of all breast cancer patients diagnosed in 1992 was selected from the population-based Thames Cancer Registry. The data for 309 patients with stage I-III tumours were analysed by hospital type using local guidelines. No difference between specialist (high volume) and non-specialist centres was detected for factors important in survival. Pathological staging was good with over 70% reporting tumour size and grade. A small number of patients were undertreated; after conservative surgery, 10% (19) of women did not receive radiotherapy, and 15% (8) of node-positive premenopausal women did not receive chemotherapy or ovarian ablation. In contrast, a significant trend with hospital volume was found for several quality of life factors. These included access to a specialist breast surgeon and specialist breast nurses, availability of fine-needle aspiration (FNA), which ranged from 84% in high-volume to 42% in low-volume centres, and quality of surgery (axillary clearance rates ranged from 51% to 8% and sampling of less than three nodes from 3% to 25% for high- and very low-volume centres respectively). Confidential feedback of results to surgeons was welcomed and initiated change. The summary information gave purchasers information relevant to the evaluation of cancer services. While the audit applied present standards to past practice, it provided the impetus for prospective audit of current practice (now being implemented in North Thames).
The feasibility and cost of a large multicentre audit of process and outcome of prostatectomy.
Emberton, M; Neal, D E; Black, N; Harrison, M; Fordham, M; McBrien, M P; Williams, R E; McPherson, K; Develin, H B
1995-01-01
Objective--To determine the feasibility of performing multicentre process and outcome audits of common interventions taking prostatic procedures as an example. Design--Prospective, cohort study. Setting--All National Health Service and independent hospitals in Northern, Wessex, Mersey, and South West Thames health regions. Patients--5361 men undergoing prostatectomy identified by 103 of the 107 urologists and general surgeons performing prostatectomy in the study regions. Main measures-- Rates of participation by surgeons and patients; completeness of clinical data provided by surgeons; patient response rate and completeness of patient derived data; and cost. Results--Most surgeons (103,96%) agreed to participate. Overall, the proportion of eligible patients invited to take part was high (89%), although this was only measured in South West Thames, where dedicated data collectors were employed. Few men (80, 1.5%) declined to participate. Of those surviving for three months after surgery, 82.4% (4226) completed and returned the postal questionnaire. The response rate was higher in South West Thames (86.7%) than in the other regions (80.6%-80.8%). The audit was well received: 91% of patients found the questionnaire easy to complete and only 2.3% of them disapproved. Completeness of data was high with both the hospital and patient questionnaires. Missing data occurred in less than 5% of responses to most questions. The attributable cost was 34.50 pounds per patient identified or 44 pounds for patients in whom either the treatment outcome or vital status was known three months after their prostatectomy. Conclusions--This multicentre audit of process and outcome of prostatectomy proved feasible in terms of surgeon participation, patient identification, and the quantity and quality of data collection. Whether the cost was warranted will depend on how surgeons use the audit data to modify their practice. PMID:10156395
Protean and Boundaryless Careers: A Study on Potential Motivators
ERIC Educational Resources Information Center
Segers, Jesse; Inceoglu, Ilke; Vloeberghs, Daniel; Bartram, Dave; Henderickx, Erik
2008-01-01
This paper conceptually links hypothesized scales of the Motivation Questionnaire (SHL (1992). "Motivation questionnaire: Manual and users' guide". Thames Ditton: SHL) to the underlying dimensions of the protean (values-driven and self-directedness) and boundaryless career (physical and psychological mobility) attitudes. Results of…
Cooper, Keith; Burdon, Daryl; Atkins, Jonathan P; Weiss, Laura; Somerfield, Paul; Elliott, Michael; Turner, Kerry; Ware, Suzanne; Vivian, Chris
2013-10-15
Physical and biological seabed impacts can persist long after the cessation of marine aggregate dredging. Whilst small-scale experimental studies have shown that it may be possible to mitigate such impacts, it is unclear whether the costs of restoration are justified on an industrial scale. Here we explore this question using a case study off the Thames Estuary, UK. By understanding the nature and scale of persistent impacts, we identify possible techniques to restore the physical properties of the seabed, and the costs and the likelihood of success. An analysis of the ecosystem services and goods/benefits produced by the site is used to determine whether intervention is justified. Whilst a comparison of costs and benefits at this site suggests restoration would not be warranted, the analysis is site-specific. We emphasise the need to better define what is, and is not, an acceptable seabed condition post-dredging. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.
The mute swan, its status, behavior, and history in the U. K
Lohnes, E.J.R.; Perry, Matthew C.
2004-01-01
For many years the mute swan has been considered a royal bird. It is a prominent resident throughout the United Kingdom (U.K.), often found on the inland waterways. Some people consider it to be a nonmigratory native bird because it doesn't tend to move large distances and doesn't often venture far from freshwater. A mute swan may often live out its life cycle in the same river valley in which it hatched. Over the last 30-40 years, a large amount of research has been carried out on their life cycle, behavior, and mortality caused by such factors as lead poisoning from fishing weights. Throughout the U.K., there are a number of areas where mute swans may be found in large numbers, including (1) the River Thames (which passes through London), (2) Slimbridge Wetlands Center, (3) Berwick-upon- Tweed (the second largest mute swan colony in Britain), and (4) Abbotsbury Swannery (the worlds only managed swan colony). This last site is a truly unique area, and each year it often has over 150 nesting pairs producing between 2-12 eggs per nest. The management is minimal, and the site is ideal for their requirements because it is close to a number of freshwater sources, and has good nesting sites and large quantities of eelgrass Zostera marina and widgeon grass Ruppia maritima, their preferred food sources. The Swannery is located on the south coast of England at the western end of the Fleet Lagoon, a micro-tidal estuary, which borders the English Channel.
Landowner preferences for wetlands conservation programs in two Southern Ontario watersheds.
Trenholm, Ryan; Haider, Wolfgang; Lantz, Van; Knowler, Duncan; Haegeli, Pascal
2017-09-15
Wetlands in the region of Southern Ontario, Canada have declined substantially from their historic area. Existing regulations and programs have not abated this decline. However, reversing this trend by protecting or restoring wetlands will increase the supply of important ecosystem services. In particular, these actions will contribute to moderating the impacts of extreme weather predicted to result from climate change as well as reducing phosphorous loads in Lake Erie and ensuing eutrophication. Since the majority of land in the region is privately owned, landowners can play an important role. Thus, we assessed landowner preferences for voluntary incentive-based wetlands conservation programs using separate choice experiments mailed to farm and non-farm landowners in the Grand River and Upper Thames River watersheds. Latent class models were separately estimated for the two data sets. Marginal willingness to accept, compensating surplus, and participation rates were estimated from the resulting models to gain insight into the financial compensation required by landowners and their potential participation. Many of the participating landowners appear willing to participate in wetlands conservation at reasonable cost, with more willing groups notably marked by past participation in incentive-based conservation programs. They generally favor wetlands conservation programs that divert smaller areas of land to wetlands conservation, target marginal agricultural land, use treed buffers to protect wetlands, offer technical help, and pay financial incentives. However, landowners appear reluctant to receive public recognition of their wetland conservation actions. Our results are of interest to natural resource managers designing or refining wetlands conservation programs. Copyright © 2017 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Howden, Nicholas J. K.; Burt, Tim P.; Worrall, Fred; Mathias, Simon; Whelan, Mick J.
2011-06-01
Widespread pollution of groundwater by nutrients due to 20th century agricultural intensification has been of major concern in the developed world for several decades. This paper considers the River Thames catchment (UK), where water-quality monitoring at Hampton (just upstream of London) has produced continuous records for nitrate for the last 140 years, the longest continuous record of water chemistry anywhere in the world. For the same period, data are available to characterize changes in both land use and land management at an annual scale. A modeling approach is used that combines two elements: an estimate of nitrate available for leaching due to land use and land management; and, an algorithm to route this leachable nitrate through to surface or groundwaters. Prior to agricultural intensification at the start of World War II, annual average inputs were around 50 kg ha-1, and river concentrations were stable at 1 to 2 mg l-1, suggesting in-stream denitrification capable of removing 35 (±15) kt N yr-1. Postintensification data suggest an accumulation of 100 (±40) kt N yr-1 in the catchment, most of which is stored in the aquifer. This build up of reactive N species within the catchments means that restoration of surface nitrate concentrations typical of the preintensification period would require massive basin-wide changes in land use and management that would compromise food security and take decades to be effective. Policy solutions need to embrace long-term management strategies as an urgent priority.
Study of Discontinuing Students at Macquarie University.
ERIC Educational Resources Information Center
Baumgart, Neil
1977-01-01
Student responses to a questionnaire on 88 dropout prediction variables indicated that prevention of such wastage should be specific to student subgroup and should focus on colllege freshmen. (Available in microfiche from: Carfax Publishing Company, Haddon House, Dorchester-on-Thames, Oxford 0X9 8JZ, England.) (CP)
56. Detail of gear for Marine Railway #2, steam powered ...
56. Detail of gear for Marine Railway #2, steam powered Marine Railway Headhouse, south end: hole in foreground is where gear now installed in Headhouse for Marine Railway #3 was removed. - Thames Tow Boat Company, Foot of Farnsworth Street, New London, New London County, CT
Are Endocrine Disrupting Compounds a Health Risk in Drinking Water?
Falconer, Ian R.
2006-01-01
There has been a great deal of international discussion on the nature and relevance of endocrine disrupting compounds in the environment. Changes in reproductive organs of fish and mollusks have been demonstrated in rivers downstream of sewage discharges in Europe and in North America, which have been attributed to estrogenic compounds in the effluent. The anatomical and physiological changes in the fauna are illustrated by feminization of male gonads. The compounds of greatest hormonal activity in sewage effluent are the natural estrogens 17β-estradiol, estrone, estriol and the synthetic estrogen ethinylestradiol. Androgens are also widely present in wastewaters. Investigations of anthropogenic chemical contaminants in freshwaters and wastewaters have shown a wide variety of organic compounds, many of which have low levels of estrogenic activity. In many highly populated countries the drinking water is sourced from the same rivers and lakes that are the recipients of sewage and industrial discharge. The River Thames which flows through London, England, has overall passed through drinking water and sewage discharge 5 times from source to mouth of the river. Under these types of circumstance, any accumulation of endocrine disrupting compounds from sewage or industry potentially affects the quality of drinking water. Neither basic wastewater treatment nor basic drinking water treatment will eliminate the estrogens, androgens or detergent breakdown products from water, due to the chemical stability of the structures. Hence a potential risk to health exists; however present data indicate that estrogenic contamination of drinking water is very unlikely to result in physiologically detectable effects in consumers. Pesticide, detergent and industrial contamination remain issues of concern. As a result of this concern, increased attention is being given to enhanced wastewater treatment in locations where the effluent is directly or indirectly in use for drinking water. In some places at which heavy anthropogenic contamination of drinking water sources occurs, advanced drinking water treatment is increasingly being implemented. This treatment employs particle removal, ozone oxidation of organic material and activated charcoal adsorption of the oxidation products. Such processes will remove industrial organic chemicals, pesticides, detergents, pharmaceutical products and hormones. Populations for which only basic wastewater and drinking water treatment are available remain vulnerable. PMID:16823090
Zimmerman, Marc James; Grady, S.J.; Trench, E.C.; Flanagan, S.M.; Nielsen, M.G.
1996-01-01
This retrospective report examines available nutrient, suspended sediment, and pesticide data in surface and ground water in the Connecticut, Housatonic and Thames Rivers Study Unit of the National Water-Quality Assessment Program. The purpose of this study is to improve the under- standing of natural and anthropogenic factors affecting water quality in the study unit. Water-quality data were acquired from various sources, primarily, the U.S. Geological Survey and the U.S. Environmental Protection Agency. The report examines data for water years 1972-92, focusing on 1980-92, although it also includes additional data from as early as 1905. The study unit lies within the New England Physiographic Province and altitudes range from sea level in coastal Connecticut to 6,288 feet above sea level at Mount Washington, New Hampshire. Two major aquifer types underlie the study unit--unconsolidated glacial deposits and fractured bedrock. The climate generally is temperate and humid, with four distinct seasons. Average annual precipitation ranges from 34 to 65 inches. The study unit has a population of about 4.5 million, which is most highly concentrated in southwestern Connecticut and along the south-central region of the Connecticut River Valley. Surface-water-quality data were screened to provide information about sites with adequate numbers of analyses (50) over sufficiently long periods (1980-90) to enable valid statistical analyses. In order to compare effects of different types of land use on surface-water quality, examination of data required application of several statistical and graphical techniques, including mapping, histograms, boxplots, concentration-discharge plots, trend analysis, and load estimation. Spatial and temporal analysis of surface-water-quality data indicated that, with a single exception, only/stations in the Connecticut water-quality network had sufficient data collected over adequately long time periods to use in detailed analyses. Ground-water nutrient and pesticide data were compiled from several Federal and State agencies, primarily the U.S. Geological Survey, U.S. Environmental Protection Agency, and Connecticut Department of Health Services. Nutrient data were available for several thousand wells; nitrite plus nitrate as nitrogen was the most commonly reported constituent. Most wells with nutrient data are in Massachusetts and Connecticut. Relative to nutrient data in ground and surface water, pesticide data are less common. Pesticide data were available for slightly more than 200 surface-water sites and less than 500 wells; about 95 percent of the wells are completed in stratified-drift or till aquifers. Data for 81 pesticide compounds were available in various data bases. 2,4-D and silvex were the most commonly detected herbicides in surface water and dieldrin and diazinon were the most commonly detected insecticides. Most surface-water pesticide samples and detections are from bed sediment, but much of the data are not recent. Ethylene dibromide (EDB), a soil fumigant used in tobacco farming was detected in 268 well in a 50 square-mile area of north-central Connecticut; EDB contamination also was detected in wells in Massachusetts. Atrazine, an herbicide commonly used in corn farming, commonly was detected in wells installed in tilled agricultural fields. Corn herbicides were commonly detected in the northern par( of the study unit, although the sampling has been less frequent than in the southern part of the study unit. Pesticides were seldom detected in public-supply wells in Connecticut. Urban sites with relatively high population densities and high concentrations of dischargers were characterized by having the highest nutrient concentrations and loads when adjusted for differences in drainage area or population. Particularly, the Pequabuck, Naugatuck, and Quinnipiac River Basins were characterized by high nutrient concentrations--median total nitrogen concentrations ranged from 3.3 to 4.2 mg
New approaches to job-sharing of training posts in the North Thames region.
Goldberg, I; Paice, E
This paper proposes a new way of managing the provision of flexible training opportunities by job-sharing. It shows how the difficulties of implementing job-sharing can be overcome, and gives an example of implementation of job-sharing in the context of flexible training.
Weberian Perspectives and the Study of Education.
ERIC Educational Resources Information Center
King, Ronald
1980-01-01
Considers the sociological research of Max Weber in relation to recent sociology of education. Elements of his approach (social action, power, authority and bureaucracy, ideology, and class) are compared with other approaches. Journal available from Carfax Publishing Co., Haddon House, Dorchester-on-Thames, Oxford 0X9 8JZ, England. (Author/DB)
2017-12-08
NASA image acquired March 26, 2012 This nearly cloud-free view of Great Britain and Ireland was acquired by the Moderate Resolution Imaging Spectroradiometer (MODIS) aboard NASA’s Terra satellite on March 26, 2012. Just a few days into spring, most of the land appears green, although not quite as brilliant as the summertime hues that give Ireland the nickname “the Emerald Island”. The islands of Ireland (west) and Great Britain (east) are separated by the Irish Sea, which is filled with the turquoise, green and tan swirls typical of sediment, although blooming algae could also contribute some color to the waters. To the southeast, the English Channel separates the island of Great Britain from France (south) and Belgium (north). London can be seen as a gray circle situated inland on the tan-colored River Thames. The sediment from the Thames flows into the English Channel due east of London. The United Kingdom is made up of Wales, Scotland and England, all located primarily on the island of Great Britain, and of Northern Ireland, which comprises the northern section of the island of Ireland. Dublin, in the Republic of Ireland, can be seen as a gray smudge on the eastern coast of the island. Almost due west Galway can be seen as a linear gray streak on the northern coast of Galway Bay, with the blue waters of Loch Corrib to the north. Most of the United Kingdom and Ireland are part of the Celtic broadleaf forest ecoregion, where acid-loving oak and mixed oak forests abound, along with fen and swamp forests and ombrotrophic mires. A portion of the Scottish Highlands, in the north of Great Britain, are covered by the Caledon conifer forest ecoregion. The Caledonia conifers once covered a large area of Scotland, but now only about 1% of the original forest survives, mostly high in the cooler areas of the Highlands. NASA/GSFC/Jeff Schmaltz/MODIS Land Rapid Response Team NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram
Dementia Guide for Carers and Care Providers.
2017-05-10
This app is for carers of people with dementia. Developed by Health Education England's Thames Valley team in partnership with the University of Reading and in collaboration with healthcare professionals and carers, it offers practical information to support users' understanding of the progressive nature of dementia and the challenges of caring for someone with the condition.
An Investigation of Atmospheric Dynamics through Their Effects on Mesospheric Optical Emission.
1987-03-23
continuous variation in the phase of the response in between (Thome, [1968], Testud & Francois (1971), Klostermeyer (1972 a,b) Porter and Than (1974...Walterscheid, Trans. Amer. Geophys. Union, 66, 97, (1985). 23. Testud , J. and P. Francois, J. Atmos. Terr. Phys. 33, 765, (1971). 24. Thame, G.D., J
ERIC Educational Resources Information Center
Walters, Charles David
2017-01-01
Quantitative reasoning (P. W. Thompson, 1990, 1994) is a powerful mathematical tool that enables students to engage in rich problem solving across the curriculum. One way to support students' quantitative reasoning is to develop prospective secondary teachers' (PSTs) mathematical knowledge for teaching (MKT; Ball, Thames, & Phelps, 2008)…
Sims, Alison
2016-10-07
The Children's Hospitals Network (CHN) was formed in 2012 following a review of national specialist services. Oxford University Hospitals NHS Foundation Trust (OUH) and the University Hospital Southampton NHS Foundation Trust (UHS) collaborated in its formation, with the CHN hosting clinical and operational networks across more than 20 district general hospitals in the Thames Valley and Wessex regions.
78 FR 67361 - Public Water System Supervision Program Revision for the Commonwealth of Kentucky
Federal Register 2010, 2011, 2012, 2013, 2014
2013-11-12
... Drinking Water Branch, 61 Forsyth Street SW., Atlanta, Georgia 30303. FOR FURTHER INFORMATION CONTACT: Mr. Brian Thames, the EPA Region 4, Safe Drinking Water Branch, at the address given above, by telephone at... Kentucky submitted requests that the Region approve revisions to the Commonwealth's Safe Drinking Water Act...
47. Detail of gears for steam powered Marine Railway #1, ...
47. Detail of gears for steam powered Marine Railway #1, and drive equipment for Railways #l and #2, Marine Railway Headhouse, ground floor, north end, drive gears in foreground, pulling gears for Railway # 1 in background. - Thames Tow Boat Company, Foot of Farnsworth Street, New London, New London County, CT
Watt, B.E.; Malcolm, R.L.; Hayes, M.H.B.; Clark, N.W.E.; Chipman, J.K.
1996-01-01
Humic substances are amorphous organic macromolecules responsible for the hue of natural waters. They are also known to be precursors of mutagens formed on chlorination prior to distribution of drinking water. In this study humic substances from the waters of primary streams, from major rivers, and from reservoirs were isolated and fractionated into humic acids (HA), fulvic acids (FA) and XAD-4 acids using columns of XAD-8 and of XAD-4 resins in tandem, and the fractions from the different sources were chlorinated and assayed for mutagenicity. CPMAS 13C NMR spectroscopy showed marked differences in compositions not only between HA, FA, and XAD-4 acids from the same water samples, but also between the same fractions from water samples from different watersheds. There were found to be strong similarities between the fractions from watersheds which had closely related soil types. Aromaticity was greatest in HAs, and lowest in XAD-4 acids, and carboxyl contents and aliphatic character were greatest in the XAD-4 acids. Carbon content decreased in the order HA > FA > XAD-4 acids, and amino acids and neutral sugars contents decreased in the order HA > XAD-4 > FA. Titration data complemented aspects of the NMR data, demonstrating that carboxyl content decreased in the order XAD-4 acids > FA > HA, and indicated that phenolic character was highest in HAs and lowest in the XAD-4 acids. All samples tested gave rise to bacterial mutagens on chlorination. Although the mutagenicities were of the same order of magnitude for the chlorinated humic samples from the different sources, the samples which showed the greatest number of revertant bacterial colonies were from the Thames and Trent, large rivers with humic materials from diverse environments, and relatively high in amino acid contents.
Simulating groundwater-induced sewer flooding
NASA Astrophysics Data System (ADS)
Mijic, A.; Mansour, M.; Stanic, M.; Jackson, C. R.
2016-12-01
During the last decade, Chalk catchments of southern England experienced severe groundwater flooding. High groundwater levels resulted in the groundwater ingress into the sewer network that led to restricted toilet use and the overflow of diluted, but untreated sewage to road surfaces, rivers and water courses. In response to these events the water and sewerage company Thames Water Utilities Ltd (TWUL) had to allocate significant funds to mitigate the impacts. It was estimated that approximately £19m was spent responding to the extreme wet weather of 2013-14, along with the use of a fleet of over 100 tankers. However, the magnitude of the event was so large that these efforts could not stop the discharge of sewage to the environment. This work presents the analysis of the risk of groundwater-induced sewer flooding within the Chalk catchment of the River Lambourn, Berkshire. A spatially distributed groundwater model was used to assess historic groundwater flood risk and the potential impacts of changes in future climate. We then linked this model to an urban groundwater model to enable us to simulate groundwater-sewer interaction in detail. The modelling setup was used to identify relationships between infiltration into sewers and groundwater levels at specific points on TWUL's sewer network, and to estimate historic and future groundwater flood risk, and how this varies across the catchment. The study showed the significance of understanding the impact of groundwater on the urban water systems, and producing information that can inform a water company's response to groundwater flood risk, their decision making process and their asset management planning. However, the knowledge gained through integrated modelling of groundwater-sewer interactions has highlighted limitations of existing approaches for the simulation of these coupled systems. We conclude this work with number of recommendations about how to improve such hydrological/sewer analysis.
NASA Astrophysics Data System (ADS)
Mortazavi-Naeini, M.; Bussi, G.; Hall, J. W.; Whitehead, P. G.
2016-12-01
The main aim of water companies is to have a reliable and safe water supply system. To fulfil their duty the water companies have to consider both water quality and quantity issues and challenges. Climate change and population growth will have an impact on water resources both in terms of available water and river water quality. Traditionally, a distinct separation between water quality and abstraction has existed. However, water quality can be a bottleneck in a system since water treatment works can only treat water if it meets certain standards. For instance, high turbidity and large phytoplankton content can increase sharply the cost of treatment or even make river water unfit for human consumption purposes. It is vital for water companies to be able to characterise the quantity and quality of water under extreme weather events and to consider the occurrence of eventual periods when water abstraction has to cease due to water quality constraints. This will give them opportunity to decide on water resource planning and potential changes to reduce the system failure risk. We present a risk-based approach for incorporating extreme events, based on future climate change scenarios from a large ensemble of climate model realisations, into integrated water resources model through combined use of water allocation (WATHNET) and water quality (INCA) models. The annual frequency of imposed restrictions on demand is considered as measure of reliability. We tested our approach on Thames region, in the UK, with 100 extreme events. The results show increase in frequency of imposed restrictions when water quality constraints were considered. This indicates importance of considering water quality issues in drought management plans.
Chesapeake Bay Future Conditions Report. Volume 11. Biota.
1977-12-01
United States. Fishery concentrated in Thames estuary (Hancock , et al., 1956). Non- nutritional Roles Competition : Membranipora encrusts fronds. Other...Non- nutritional Role Competition : D. leucolena is in competition for space with certain othe? epifaunal species , espec ially hydro ids and...Zoothamnium and other protozoans. Non- nutritional Role Competition : Competes with other estuarine filter-feeding herbivores and detritovores. Non
Probing Nanoscale Ferroelectricity by Ultraviolet Raman Spectroscopy
2006-09-15
Breaking the Maya Code (Thames & Hudson, London, rev. ed., 1999), p. 13. 11. S. D. Houston, M. D. Coe, Mexicon 25, 151 (2004). 12. K. A. Taube...in Olmec Art and Archaeology in Mesoamerica, J. E. Clark, M. E. Pye, Eds. (Yale Univ. Press, New Haven, CT, 2000), pp. 75–93. 19. K. H. Basso, N
NASA Astrophysics Data System (ADS)
Voss, Anja; Bärlund, Ilona; Punzet, Manuel; Williams, Richard; Teichert, Ellen; Malve, Olli; Voß, Frank
2010-05-01
Although catchment scale modelling of water and solute transport and transformations is a widely used technique to study pollution pathways and effects of natural changes, policies and mitigation measures there are only a few examples of global water quality modelling. This work will provide a description of the new continental-scale model of water quality WorldQual and the analysis of model simulations under changed climate and anthropogenic conditions with respect to changes in diffuse and point loading as well as surface water quality. BOD is used as an indicator of the level of organic pollution and its oxygen-depleting potential, and for the overall health of aquatic ecosystems. The first application of this new water quality model is to river systems of Europe. The model itself is being developed as part of the EU-funded SCENES Project which has the principal goal of developing new scenarios of the future of freshwater resources in Europe. The aim of the model is to determine chemical fluxes in different pathways combining analysis of water quantity with water quality. Simple equations, consistent with the availability of data on the continental scale, are used to simulate the response of in-stream BOD concentrations to diffuse and anthropogenic point loadings as well as flow dilution. Point sources are divided into manufacturing, domestic and urban loadings, whereas diffuse loadings come from scattered settlements, agricultural input (for instance livestock farming), and also from natural background sources. The model is tested against measured longitudinal gradients and time series data at specific river locations with different loading characteristics like the Thames that is driven by domestic loading and Ebro with relative high share of diffuse loading. With scenario studies the influence of climate and anthropogenic changes on European water resources shall be investigated with the following questions: 1. What percentage of river systems will have degraded water quality due to different driving forces? 2. How will climate change and changes in wastewater discharges affect water quality? For the analysis these scenario aspects are included: 1. climate with changed runoff (affecting diffuse pollution and loading from sealed areas), river discharge (causing dilution or concentration of point source pollution) and water temperature (affecting BOD degradation). 2. Point sources with changed population (affecting domestic pollution), connectivity to treatment plants (influencing domestic and manufacturing pollution as well as input from sealed areas and scattered settlements).
Climate at the edge of human dispersal in the European Middle Pleistocene
NASA Astrophysics Data System (ADS)
Horne, David
2014-05-01
Pleistocene palaeoclimatic reconstructions based on fossils from sites containing archaeological evidence of human occupation can answer key questions about the climatic context of early human dispersal in Europe. Biological proxies including foraminifera, ostracods, diatoms, chironomid larvae, molluscs and pollen are widely used to estimate palaeoclimatic parameters, typically palaeotemperatures, using indicator species, Mutual Climatic Range (MCR), Modern Analogue Technique (MAT) and transfer function approaches. Any single proxy method will yield plausible results, but there is a need for multi-proxy testing; matching or overlapping results inspire confidence, whereas if independent proxies yield results that do not match or even overlap, one or more must be wrong. The Multi-Proxy Consensus (MPC) approach not only compares two or more proxy results in order to check for agreement, but also offers potential for more refined results to be obtained from the range of mutual agreement between two or more overlapping palaeotemperature ranges. Studies of MIS9 (late Middle Pleistocene) deposits in the Thames-Medway river system in SE England (some of which contain stone implements representing human occupation) have yielded palaeotemperature estimates based on ostracods, beetles, fish, herpetiles, pollen and plant macrofossils. The MPC approach demonstrates the consistency of the results and defines a more continental climate than today (mean July air temperatures similar or 1 degree warmer, mean January air temperatures at least 2 degrees colder). Two River Thames MIS11 sites (Ebbsfleet and Swanscombe) have yielded MPC results indicating summers up to 1.5 degrees warmer and winters at least 5 degrees colder than today. British early Middle Pleistocene sites record the earliest human presence in Europe North of the Alps. At Boxgrove (MIS13), well-known for its rich record of human activity (stone tools and butchered bones), combined ostracod and herpetile MCR results indicate summers within 3 degrees (above or below) of present day values, but winters at least 2 degrees colder, consistent with the mutual consensus of beetle and ostracod MCR results from another MIS13 human occupation site, Waverley Wood. Comparable MPC results have been obtained from older sites including Sugworth (MIS15?), Norton Subcourse and West Runton (both MIS17-15?); although none of these has yielded evidence of human presence they are potentially informative about the climatic context of Pakefield (MIS19 or 17), one of the earliest British sites with such evidence, where palaeoclimate reconstruction (warmer summers, winters similar to or colder than today) is based solely on the beetles. Likewise only the beetle MCR method has thus far been applied to the oldest known human occupation site in Britain, Happisburgh (MIS25 or 21), where similar summers and colder winters are again indicated; as yet no opportunity has arisen to check this result against another proxy. Human colonization of these sites by dispersal from more southerly populations had to contend with colder/longer winters, requiring greater dependence on meat for food because plant resources were only available in warmer months. Adaptive strategies likely involved using shelters and animal hides to keep warm, and eventually also fire (at least by MIS11), rather than seasonal migrations or physiological adaptations.
ERIC Educational Resources Information Center
Entwistle, Noel J.; And Others
1977-01-01
Volume 1 discusses a large-scale follow-up study of the correlates of academic success in 2,595 college students. Volume 2 presents a philosophical and historical approach to studying educational objectives. (Available in microfiche from: Carfax Publishing Company, Haddon House, Dorchester-on-Thames, Oxford 0X9 8JZ, England.) (CP)
Haudenosaunee Genealogies: Conflict and Community in the Oneida Land Claim
ERIC Educational Resources Information Center
Ackley, Kristina
2009-01-01
The Oneidas have a history marked by land dispossession and removal from a once vast homeland. In 2009, there are three Oneida communities that share in litigation for the return of the homeland; in New York (2,000 members), at the Thames community near Southwold, Ontario (5,000 members), and in Wisconsin (15,000 members). Those hostile to the…
28. VIEW OF WHITE SAGE PRIOR TO BEING PAINTED COAST ...
28. VIEW OF WHITE SAGE PRIOR TO BEING PAINTED COAST GUARD COLORS OF BLACK AND WHITE. NOTE ALSO THE PHOTOGRAPH WAS TAKEN PRIOR TO THE INSTALLATION OF A-FRAME MAST AND BOOM AND TO THE CONSTRUCTION OF TURTLE DECK. - U.S. Coast Guard Cutter WHITE SAGE, U.S. Coast Guard 1st District Base, 1 Thames Street, Bristol, Bristol County, RI
Water recycling at the Millennium Dome.
Hills, S; Smith, A; Hardy, P; Birks, R
2001-01-01
Thames Water is working with the New Millennium Experience Company to provide a water recycling system for the Millennium Dome which will supply 500 m3/d of reclaimed water for WC and urinal flushing. The system will treat water from three sources: rainwater--from the Dome roof greywater--from handbasins in the toilet blocks groundwater--from beneath the Dome site The treatment technologies will range from "natural" reedbeds for the rainwater, to more sophisticated options, including biological aerated filters and membranes for the greywater and groundwater. Pilot scale trials were used to design the optimum configuration. In addition to the recycling system, water efficient devices will be installed in three of the core toilet blocks as part of a programme of research into the effectiveness of conservation measures. Data on water usage and customer behaviour will be collected via a comprehensive metering system. Information from the Dome project on the economics and efficiency of on-site recycling at large scale and data on water efficient devices, customer perception and behaviour will be of great value to the water industry. For Thames Water, the project provides vital input to the development of future water resource strategies.
Trinder, Valerie M; Fleet, Geoffrey E; Gray, Anne E
2007-03-01
This study was undertaken to provide evidence that library outreach projects in the NHS in the Thames Valley Strategic Health Authority area were effective and could justify continued funding. The object was to assess whether information literacy skills training taken up by health professionals impacts on their confidence and skills in using electronic sources of health information. A total of 487 health professionals taking up training on a voluntary basis were assessed by completing a self-assessment questionnaire prior to and after training to establish their information literacy skills and confidence levels. Of these, 223 trainees (46%) also returned 6-week follow-up questionnaires. Results showed that 464 trainees (95%) intended to apply what they had learnt in a variety of ways; use of specific resources greatly increased after training and confidence in using them increased substantially. Use of search techniques increased considerably overall, whereas use of Google decreased. The major findings of this research are that training health-care personnel in the use of electronic resources impacts positively on their information literacy skills and confidence, and that the information available to them is considered to have potential value across health-care practice.
Using Sentinel-1 SAR satellites to map wind speed variation across offshore wind farm clusters
NASA Astrophysics Data System (ADS)
James, S. F.
2017-11-01
Offshore wind speed maps at 500m resolution are derived from freely available satellite Synthetic Aperture Radar (SAR) data. The method for processing many SAR images to derive wind speed maps is described in full. The results are tested against coincident offshore mast data. Example wind speed maps for the UK Thames Estuary offshore wind farm cluster are presented.
ERIC Educational Resources Information Center
Browning, Genia; Linn, Pamela
A project was designed to assist older unemployed people in London, England, with the transition to education, vocational training, and employment. The project involved the development of a local tourist guide course at Thames Polytechnic (England), the accreditation of this course, and employment of some of the participants as local tourist…
Flood risk change in some European, African and Asian catchments
NASA Astrophysics Data System (ADS)
Kreibich, Heidi
2017-04-01
In light of the expected increase of flood risk in large parts of the world due to climate change and globally increasing exposure, efficient integrated flood risk management needs to be implemented. Societies learn from floods, and consequently improve their risk management. Such learning can occur through 'focusing events', i.e. events that provide a sudden, strong push for action. For example, the 1953 North Sea flood triggered the Delta Works in The Netherlands and the construction of the Thames Barrier. We show how societies have learnt from focusing events in river systems, by a semi-quantitative assessment of eight paired flood events around the world, i.e. consecutive floods that occurred in the same catchments, with the second flood causing significantly lower damage. We unravel the main mechanisms underlying these eight success stories of risk reduction. Across all case studies, we find that lower damage caused by the second event was mainly due to significant reductions in vulnerability. The role of changes in exposure is less apparent; positive and negative changes are reported. In some cases, significant investments in flood protection between the floods have played a large role in exposure and damage reduction. Reduction of vulnerability seems to be a key for better risk reduction via integrated flood risk management. Thus, we need to redouble efforts to improve our understanding of vulnerability.
Investigating low flow process controls, through complex modelling, in a UK chalk catchment
NASA Astrophysics Data System (ADS)
Lubega Musuuza, Jude; Wagener, Thorsten; Coxon, Gemma; Freer, Jim; Woods, Ross; Howden, Nicholas
2017-04-01
The typical streamflow response of Chalk catchments is dominated by groundwater contributions due the high degree of groundwater recharge through preferential flow pathways. The groundwater store attenuates the precipitation signal, which causes a delay between the corresponding high and low extremes in the precipitation and the stream flow signals. Streamflow responses can therefore be quite out of phase with the precipitation input to a Chalk catchment. Therefore characterising such catchment systems, including modelling approaches, clearly need to reproduce these percolation and groundwater dominated pathways to capture these dominant flow pathways. The simulation of low flow conditions for chalk catchments in numerical models is especially difficult due to the complex interactions between various processes that may not be adequately represented or resolved in the models. Periods of low stream flows are particularly important due to competing water uses in the summer, including agriculture and water supply. In this study we apply and evaluate the physically-based Pennstate Integrated Hydrologic Model (PIHM) to the River Kennet, a sub-catchment of the Thames Basin, to demonstrate how the simulations of a chalk catchment are improved by a physically-based system representation. We also use an ensemble of simulations to investigate the sensitivity of various hydrologic signatures (relevant to low flows and droughts) to the different parameters in the model, thereby inferring the levels of control exerted by the processes that the parameters represent.
The Fracture of Thermosetting Resins after Exposure to Water.
1980-09-01
formaldehyde , urea - formaldehyde and melamine - formaldehyde resins , epoxides, unsaturated polyesters, diallyl phthalate resins , furanes and certain kinds...linked phenol- formaldehyde (27) and epoxy resins (22), but some work on the fracture surfaces of polyesters with varying flexibiliser additions has been...AO0-A099 975 KINGSTON POLYTECHNIC KINGSTON UPON THAMES (ENGLAND) F/G 11/9 THE FRACTURE OF THERMOSETTING RESINS AFTER EXPOSURE TO WATER.(U) SEP 80 6
Survey of Maritime Experiences in Reduced Workload and Staffing
1999-07-01
flexibility. National Technical University of Athens. ATOMOS (Advanced Technology to optimize manpower onboard ships) Project Rationale. (1996) http...applied R&D in this area, sponsored project ATOMOS , within its EURET transport R&D programme. ATOMOS consists of a consortium of 9 partners from 4 EU...period December 1994- December 1995) The THAMES Consortium consisted of the partners of two EURET consortia: ATOMOS and MASIS. Collectively, 21 partners
Lombardo, Andrea; Franco, Antonio; Pivato, Alberto; Barausse, Alberto
2015-03-01
Conventional approaches to estimating protective ecotoxicological thresholds of chemicals, i.e. predicted no-effect concentrations (PNEC), for an entire ecosystem are based on the use of assessment factors to extrapolate from single-species toxicity data derived in the laboratory to community-level effects on ecosystems. Aquatic food web models may be a useful tool to improve the ecological realism of chemical risk assessment because they enable a more insightful evaluation of the fate and effects of chemicals in dynamic trophic networks. A case study was developed in AQUATOX to simulate the effects of the anionic surfactant linear alkylbenzene sulfonate and the antimicrobial triclosan on a lowland riverine ecosystem. The model was built for a section of the River Thames (UK), for which detailed ecological surveys were available, allowing for a quantification of energy flows through the whole ecosystem. A control scenario was successfully calibrated for a simulation period of one year, and tested for stability over six years. Then, the model ecosystem was perturbed with varying inputs of the two chemicals. Simulations showed that both chemicals rapidly approach steady-state, with internal concentrations in line with the input bioconcentration factors throughout the year. At realistic environmental concentrations, both chemicals have insignificant effects on biomass trends. At hypothetical higher concentrations, direct and indirect effects of chemicals on the ecosystem dynamics emerged from the simulations. Indirect effects due to competition for food sources and predation can lead to responses in biomass density of the same magnitude as those caused by direct toxicity. Indirect effects can both exacerbate or compensate for direct toxicity. Uncertainties in key model assumptions are high as the validation of perturbed simulations remains extremely challenging. Nevertheless, the study is a step towards the development of realistic ecological scenarios and their potential use in prospective risk assessment of down-the-drain chemicals. Copyright © 2014 Elsevier B.V. All rights reserved.
Attribution of UK Winter Floods to Anthropogenic Forcing
NASA Astrophysics Data System (ADS)
Schaller, N.; Alison, K.; Sparrow, S. N.; Otto, F. E. L.; Massey, N.; Vautard, R.; Yiou, P.; van Oldenborgh, G. J.; van Haren, R.; Lamb, R.; Huntingford, C.; Crooks, S.; Legg, T.; Weisheimer, A.; Bowery, A.; Miller, J.; Jones, R.; Stott, P.; Allen, M. R.
2014-12-01
Many regions of southern UK experienced severe flooding during the 2013/2014 winter. Simultaneously, large areas in the USA and Canada were struck by prolonged cold weather. At the time, the media and public asked whether the general rainy conditions over northern Europe and the cold weather over North America were caused by climate change. Providing an answer to this question is not trivial, but recent studies show that probabilistic event attribution is feasible. Using the citizen science project weather@home, we ran over 40'000 perturbed initial condition simulations of the 2013/2014 winter. These simulations fall into two categories: one set aims at simulating the world with climate change using observed sea surface temperatures while the second set is run with sea surface temperatures corresponding to a world that might have been without climate change. The relevant modelled variables are then downscaled by a hydrological model to obtain river flows. First results show that anthropogenic climate change led to a small but significant increase in the fractional attributable risk for 30-days peak flows for the river Thames. A single number can summarize the final result from probabilistic attribution studies indicating, for example, an increase, decrease or no change to the risk of the event occurring. However, communicating this to the public, media and other scientists remains challenging. The assumptions made in the chain of models used need to be explained. In addition, extreme events, like the UK floods of the 2013/2014 winter, are usually caused by a range of factors. While heavy precipitation events can be caused by dynamic and/or thermodynamic processes, floods occur only partly as a response to heavy precipitation. Depending on the catchment, they can be largely due to soil properties and conditions of the previous months. Probabilistic attribution studies are multidisciplinary and therefore all aspects need to be communicated properly.
NASA Astrophysics Data System (ADS)
Rougé, Charles; Harou, Julien J.; Pulido-Velazquez, Manuel; Matrosov, Evgenii S.
2017-04-01
The marginal opportunity cost of water refers to benefits forgone by not allocating an additional unit of water to its most economically productive use at a specific location in a river basin at a specific moment in time. Estimating the opportunity cost of water is an important contribution to water management as it can be used for better water allocation or better system operation, and can suggest where future water infrastructure could be most beneficial. Opportunity costs can be estimated using 'shadow values' provided by hydro-economic optimization models. Yet, such models' use of optimization means the models had difficulty accurately representing the impact of operating rules and regulatory and institutional mechanisms on actual water allocation. In this work we use more widely available river basin simulation models to estimate opportunity costs. This has been done before by adding in the model a small quantity of water at the place and time where the opportunity cost should be computed, then running a simulation and comparing the difference in system benefits. The added system benefits per unit of water added to the system then provide an approximation of the opportunity cost. This approximation can then be used to design efficient pricing policies that provide incentives for users to reduce their water consumption. Yet, this method requires one simulation run per node and per time step, which is demanding computationally for large-scale systems and short time steps (e.g., a day or a week). Besides, opportunity cost estimates are supposed to reflect the most productive use of an additional unit of water, yet the simulation rules do not necessarily use water that way. In this work, we propose an alternative approach, which computes the opportunity cost through a double backward induction, first recursively from outlet to headwaters within the river network at each time step, then recursively backwards in time. Both backward inductions only require linear operations, and the resulting algorithm tracks the maximal benefit that can be obtained by having an additional unit of water at any node in the network and at any date in time. Results 1) can be obtained from the results of a rule-based simulation using a single post-processing run, and 2) are exactly the (gross) benefit forgone by not allocating an additional unit of water to its most productive use. The proposed method is applied to London's water resource system to track the value of storage in the city's water supply reservoirs on the Thames River throughout a weekly 85-year simulation. Results, obtained in 0.4 seconds on a single processor, reflect the environmental cost of water shortage. This fast computation allows visualizing the seasonal variations of the opportunity cost depending on reservoir levels, demonstrating the potential of this approach for exploring water values and its variations using simulation models with multiple runs (e.g. of stochastically generated plausible future river inflows).
Long Island Sound Thamesville Tidal-Flood Management Water Resources Study, Norwich, Connecticut.
1981-02-01
waters are used for feeding and as spawning and nursery grounds for a variety of species, such as bluefish , Atlantic tomcod, striped bass, winter...fisheries for bluefish , ’ Atlantic tomcod, striped bass, winter flounder, American eel and alewife. r The Thames supports a heavily utilized sport fishery...for winter flounder, striped bass, white perch, American smelt, bluefish and Atlantic tomcod. Mummichog and Atlantic menhaden are the most common
Measuring the quality of junior hospital doctors in general medicine.
Jones, J M; Sanderson, C F; Black, N A
1992-05-01
During the course of a larger study aimed at relating staffing levels of junior doctors in general medicine to the safety of the care provided, it became clear that consultant doctors considered the quality of their junior staff as being at least as important as the quantity. This paper describes several attempts to develop a feasible and valid method of measuring the quality of senior house officers (SHOs) and registrars using routinely available data. Having rejected three methods and had difficulties with three other methods, a modified Delphi survey was used to explore the extent to which consultants agreed on the key attributes of a high quality SHO or registrar. Sixty-seven (60%) of all consultants in the South-West Thames and Trent regions responded to two rounds of questionnaires which revealed communication skills as being consistently the most significant factor. This was confirmed in a second, anonymous survey of 198 (78%) SHO and registrar posts in the North-West Thames region. It also became clear that consultants viewed the quality of their own SHOs and registrars as generally high. This being so it is argued that the requirement to adjust for quality, when comparing SHO and registrar levels between hospitals, is of minor importance. These results also suggest that the explicit teaching of communication skills should have a high priority in undergraduate and postgraduate education.
Many-objective optimization and visual analytics reveal key trade-offs for London's water supply
NASA Astrophysics Data System (ADS)
Matrosov, Evgenii S.; Huskova, Ivana; Kasprzyk, Joseph R.; Harou, Julien J.; Lambert, Chris; Reed, Patrick M.
2015-12-01
In this study, we link a water resource management simulator to multi-objective search to reveal the key trade-offs inherent in planning a real-world water resource system. We consider new supplies and demand management (conservation) options while seeking to elucidate the trade-offs between the best portfolios of schemes to satisfy projected water demands. Alternative system designs are evaluated using performance measures that minimize capital and operating costs and energy use while maximizing resilience, engineering and environmental metrics, subject to supply reliability constraints. Our analysis shows many-objective evolutionary optimization coupled with state-of-the art visual analytics can help planners discover more diverse water supply system designs and better understand their inherent trade-offs. The approach is used to explore future water supply options for the Thames water resource system (including London's water supply). New supply options include a new reservoir, water transfers, artificial recharge, wastewater reuse and brackish groundwater desalination. Demand management options include leakage reduction, compulsory metering and seasonal tariffs. The Thames system's Pareto approximate portfolios cluster into distinct groups of water supply options; for example implementing a pipe refurbishment program leads to higher capital costs but greater reliability. This study highlights that traditional least-cost reliability constrained design of water supply systems masks asset combinations whose benefits only become apparent when more planning objectives are considered.
NASA Astrophysics Data System (ADS)
Keshtpoor, M.; Carnacina, I.; Blair, A.; Yablonsky, R. M.
2017-12-01
Storm surge caused by Extratropical Cyclones (ETCs) has significantly impacted not only the life of private citizens but also the insurance and reinsurance industry in Great Britain. The storm surge risk assessment requires a larger dataset of storms than the limited recorded historical ETCs. Thus, historical ETCs were perturbed to generate a 10,000-year stochastic catalog that accounts for surge-generating ETCs in the study area with return periods from one year to 10,000 years. Delft3D-Flexible Mesh hydrodynamic model was used to numerically simulate the storm surge along the Great Britain coastline. A nested grid technique was used to increase the simulation grid resolution up to 200 m near the highly populated coastal areas. Coarse and fine mesh models were calibrated and validated using historical recorded water elevations. Then, numerical simulations were performed on a 10,000-year stochastic catalog. The 50-, 100-, and 500-year return period maps were generated for Great Britain coastal areas. The corresponding events with return periods of 50-, 100-, and 500-years in Humber Bay and Thames River coastal areas were identified, and simulated with the consideration of projected sea level rises to reveal the effect of rising sea levels on the inundation return period maps in two highly-populated coastal areas. Finally, the return period of Storm Xaver (2013) was determined with and without the effect of rising sea levels.
A review of the current management of impacted foreign bodies in the oesophagus in adults.
Balasubramaniam, Senthil K; Bray, Dominic; Black, Myles I; Salama, N Y; Mitchell, David B
2008-08-01
Patients with acute oesophageal obstruction, either due to a foreign body or food bolus, present to any of the specialties of Otorhinolaryngology, General Surgery, Cardiothoracic Surgery or Gastroenterology. To review current routine management of this condition, we conducted a postal survey of all the consultants in the aforementioned specialties in the South Thames region. The aims of the survey were to assess current practice and to produce a standardized management plan for these patients.
Etchegoyen, A; Stormont, F; Goldberg, I
2001-06-01
This article outlines the findings of a study which indicate that flexible training in psychiatry was considered adequate to prepare doctors for both full-time and part-time work and that those wishing to work part time had no difficulty in finding jobs after accreditation. However, there was evidence to suggest that part-time consultants experienced more problems and less job satisfaction and that part-time training and working may restrict opportunities for an academic career.
1987-12-01
with increasing frequency of oscillation, while Reed and Batter (Ref. 25) reported a decrease in fretting damage in 4140 steel when the frequency was...fatigue with reference to aircraft structures. SAE Tech. Pap. no. 790612, 1979. 15. Suresh, S. and Ritchie, R.O. Propagation of short ’atigue cracks...Library British Library, Document Supply Centre CAARC Co-ordinator, Structures Welding Institute, Library British Aerospace Kingston-upon-Thames
2006-12-01
92–101. Bovee, K . D . 1982. A guide to stream habitat analysis using the in stream flow incremental methodology. Instream Flow Information Paper No...Thames. 1991. Hydrology and the management of watersheds . Iowa State University Press, Ames, IA. Brown, J. K . 1974. Handbook for inventorying downed...woody material. General Technical Report INT-16, U.S. Department of Agriculture, Forest Service. Brown, J. K ., R. D . Oberheu, and C. M. Johnston
1982-09-01
212 Integrals," Marseille, France, 4y 22-26. 1978) (PublIshed Mengel , Marc, "On Singular Characteristic Initial Value In Springer Verleg Lecture...at the Annual PP 228 meeting of he Anmrican Society for Information Science held Mengel , Marc, "Relaxation at Critical Points: Deterministic In San...Instabilities." PP 258 24 pp., Doec 1978 (Published In Journal of Chemical Physics, Mengel , Marc S. and Thames, Jees A., Jr.. "Analytical Vol. 69, NO. 8. Oct
Archaeological Geophysics for DoD Field Use: A Guide for New and Novice Users
2009-01-01
filled ditches that had been excavated into dry natural gravel at Dorchester-on-Thames, UK (Atkinson 1953; Clark 1996; Gaffney and Gater 2003). In...application of geophysics occurred in 1958, when Martin Aitken used a proton magnetometer to detect an early kiln near Peterborough, UK (Aitken...the data density. Clark (1996) shows that as the sampling interval is decreased from 1.5 to .125 m, the ability to differentiate a kiln from a piece
NASA Astrophysics Data System (ADS)
Leakey, Chris D. B.; Attrill, Martin J.; Jennings, Simon; Fitzsimons, Mark F.
2008-04-01
Estuaries are regarded as valuable nursery habitats for many commercially important marine fishes, potentially providing a thermal resource, refuge from predators and a source of abundant prey. Stable isotope analysis may be used to assess relative resource use from isotopically distinct sources. This study comprised two major components: (1) development of a spatial map and discriminant function model of stable isotope variation in selected invertebrate groups inhabiting the Thames Estuary and adjacent coastal regions; and (2) analysis of stable isotope signatures of juvenile bass ( Dicentrarchus labrax), sole ( Solea solea) and whiting ( Merlangius merlangus) for assessment of resource use and feeding strategies. The data were also used to consider anthropogenic enrichment of the estuary and potential energetic benefits of feeding in estuarine nursery habitat. Analysis of carbon (δ 13C), nitrogen (δ 15N) and sulphur (δ 34S) isotope data identified significant differences in the 'baseline' isotopic signatures between estuarine and coastal invertebrates, and discriminant function analysis allowed samples to be re-classified to estuarine and coastal regions with 98.8% accuracy. Using invertebrate signatures as source indicators, stable isotope data classified juvenile fishes to the region in which they fed. Feeding signals appear to reflect physiological (freshwater tolerance) and functional (mobility) differences between species. Juvenile sole were found to exist as two isotopically-discrete sub-populations, with no evidence of mixing between the two. An apparent energetic benefit of estuarine feeding was only found for sole.
Godbolt, S; Williamson, J; Wilson, A
1997-06-01
One of the North Thames' pioneering consortia, the Inner London Consortium (ILC) is a complex body which includes NHS Trusts with teaching hospital university connections, community-based Trusts and general hospital acute Trusts. Within the consortium there are 12,000 trained nurses, midwives, health visitors and other professional staff working in the professions allied to medicine (PAMs), all of whom require access to and provision of appropriate library information services. In 1994, taking into account experiences elsewhere in the Region and nationally, it became clear that library issues were complex and would become acute with the move of nursing libraries from ILC Trust sites over a very short timescale. A report on the issues commissioned by the Consortium recommended that a library project, which built on existing NHS Trust PGMDE funded library resources and moved these to a multidisciplinary base to serve the consortium membership, be implemented. The objective of providing access to library information services for nurses and PAMs was achieved. Successes that emerged from the implementation included: The registration in Trust libraries of almost 12 000 new members within the initial 6-month monitoring period. The development of service level agreements and standards for the delivery of services to these new user groups. This paper describes the processes behind these significant and complex changes.
Scaber, J; Saeed, S; Ihekweazu, C; Efstratiou, A; McCarthy, N; O'Moore, E
2011-02-03
We present a series of 19 cases of invasive Group A streptococcal (iGAS) infection reported to the Thames Valley Health Protection Unit from 1 December 2010 to 15 January 2011. Ten patients died and a prodrome of influenza-like illness was reported in 14 cases.Influenza B co-infection was confirmed in four cases,three of which were fatal. Our report provides further evidence that influenza B co-infection with iGAS has the potential to cause significant morbidity and mortality.
1985-09-01
whose solution is obtained from an integral I. INTRODUCTION equation for functions defined along the boun- daries of the fluid. Longuet- Higgins and In...408, pp. 345-361 (1981). [15) Thompson, J. F., F. C. Thames and C. W. [4) Longuet- Higgins , M. S. and E. D. Mastin, "Automatic Numerical Generation...the waves are assumed to be steady then analytical work (see eg Longuet- Higgins and This paper makes some progress towards the Fox (1977) and (1978
A systematic assessment of drought termination in the United Kingdom
NASA Astrophysics Data System (ADS)
Parry, Simon; Wilby, Robert L.; Prudhomme, Christel; Wood, Paul J.
2016-10-01
Drought termination can be associated with dramatic transitions from drought to flooding. Greater attention may be given to these newsworthy and memorable events, but drought terminations that proceed gradually also pose challenges for water resource managers. This paper defines drought termination as a distinctive phase of the event. Using observed river flow records for 52 UK catchments, a more systematic and objective approach for detecting drought terminations is demonstrated. The parameters of the approach are informed by a sensitivity analysis that ensures a focus on terminations of multi-season to multi-year droughts. The resulting inventory of 467 drought terminations provides an unprecedented historical perspective on this phenomenon in the UK. Nationally and regionally coherent drought termination events are identifiable, although their characteristics vary both between and within major episodes. Contrasting drought termination events in 1995-1998 and 2009-2012 are examined in greater depth. The data are also used to assess potential linkages between metrics of drought termination and catchment properties. The duration of drought termination is moderately negatively correlated with elevation (rs = -0.47) and catchment average rainfall (rs = -0.42), suggesting that wetter catchments in upland areas of the UK tend to experience shorter drought terminations. More urbanized catchments tend to have gradual drought terminations (contrary to expectations of flashy hydrological response in such areas), although this may also reflect the type of catchments typical of lowland England. Significant correlations are found between the duration of the drought development phase and both the duration (rs = -0.29) and rate (rs = 0.28) of drought termination. This suggests that prolonged drought development phases tend to be followed by shorter and more abrupt drought terminations. The inventory helps to place individual events within a long-term context. The drought termination phase in 2009-2012 was, at the time, regarded as exceptional in terms of magnitude and spatial footprint, but the Thames river flow record identifies several comparable events before 1930. The chronology could, in due course, provide a basis for exploring the complex drivers, long-term variability, and impacts of drought termination events.
NASA Astrophysics Data System (ADS)
McGrane, S. J.; Hutchins, M. G.; Kjeldsen, T. R.; Miller, J. D.; Bussi, G.; Loewenthal, M.
2015-12-01
Urban areas are widely recognised as a key source of contaminants entering our freshwater systems, yet in spite of this, our understanding of stormwater quality dynamics remains limited. The development of in-situ, high-resolution monitoring equipment has revolutionised our capability to capture flow and water quality data at a sub-hourly resolution, enabling us to potentially enhance our understanding of hydrochemical variations from contrasting landscapes during storm events. During the winter of 2013/2014, the United Kingdom experienced a succession of intense storm events, where the south of the country experienced 200% of the average rainfall, resulting in widespread flooding across the Thames basin. We applied high-frequency (15 minute resolution) water quality monitoring across ten contrasting subcatchments (including rural, urban and mixed land-use catchments), seeking to classify the disparity in water quality conditions both within- and between events. Rural catchments increasingly behave like "urban" catchments as soils wet up and become increasingly responsive to subsequent events, however water quality response during the winter months remains limited. By contrast, increasingly urban catchments yield greater contaminant loads during events, and pre-event baseline chemistry highlights a resupply source in dense urban catchments. Wastewater treatment plants were shown to dominate baseline chemistry during low-flow events but also yield a considerable impact on stormwater outputs during peak-flow events, as hydraulic push results in the outflow of untreated solid wastes into the river system. Results are discussed in the context of water quality policy; urban growth scenarios and BMP for stormwater runoff in contrasting landscapes.
Marine Science Building Dedicated
2003-10-17
Officials cut the ribbon during dedication ceremonies of the George A. Knauer Marine Science Building on Oct. 17 at NASA Stennis Space Center (SSC). The $2.75 million facility, the first building at the test site funded by the state of Mississippi, houses six science labs, classrooms and office space for 40 faculty and staff. Pictured are, from left, Rear Adm. Thomas Donaldson, commander of the Naval Meteorology and Oceanography Command; SSC Assistant Director David Throckmorton; Dr. George A. Knauer, founder of the Center of Marine Science at the University of Southern Mississippi (USM); Lt. Gov. Amy Tuck; and USM President Dr. Shelby Thames.
Visualization Center Dedicated
2003-10-17
The dedication ceremony of the University of Southern Mississippi Center of Higher Learning (CHL) High-Performance Visualization Center at SSC was held Oct. 17. The center's RAVE II 3-D visualization system, available to both on- and off-site scientists, turns data into a fully immersive environment for the user. Cutting the ribbon are, from left, Rear Adm. Thomas Donaldson, commander of the Naval Meteorology and Oceanography Command; Jim Meredith, former director of the CHL; USM President Dr. Shelby Thames; Lt. Gov. Amy Tuck; Dr. Peter Ranelli, director of the CHL; Dewey Herring, chairman of the policy board for the CHL; and former Sen. Cecil Burge.
Visualization Center Dedicated
NASA Technical Reports Server (NTRS)
2003-01-01
The dedication ceremony of the University of Southern Mississippi Center of Higher Learning (CHL) High-Performance Visualization Center at SSC was held Oct. 17. The center's RAVE II 3-D visualization system, available to both on- and off-site scientists, turns data into a fully immersive environment for the user. Cutting the ribbon are, from left, Rear Adm. Thomas Donaldson, commander of the Naval Meteorology and Oceanography Command; Jim Meredith, former director of the CHL; USM President Dr. Shelby Thames; Lt. Gov. Amy Tuck; Dr. Peter Ranelli, director of the CHL; Dewey Herring, chairman of the policy board for the CHL; and former Sen. Cecil Burge.
Eminson, C; Dawson, D
1999-01-01
The purpose of this article is to describe the strategic context within which ambulatory care facilities are being developed, to consider a range of models of care facilities available, and, by drawing on the experience of the authors, to comment on some of the investment and development issues arising from two projects in progress--the community hospitals in Richmond, Yorkshire, in rural north England, and Thames Ditton on the borders of outer south London. In the final section, we consider the possible future of ambulatory care development in the light of government policy.
Marine Science Building Dedicated
NASA Technical Reports Server (NTRS)
2003-01-01
Officials cut the ribbon during dedication ceremonies of the George A. Knauer Marine Science Building on Oct. 17 at NASA Stennis Space Center (SSC). The $2.75 million facility, the first building at the test site funded by the state of Mississippi, houses six science labs, classrooms and office space for 40 faculty and staff. Pictured are, from left, Rear Adm. Thomas Donaldson, commander of the Naval Meteorology and Oceanography Command; SSC Assistant Director David Throckmorton; Dr. George A. Knauer, founder of the Center of Marine Science at the University of Southern Mississippi (USM); Lt. Gov. Amy Tuck; and USM President Dr. Shelby Thames.
1979-05-18
called " VAPE ." This program ’ias six modules, three of which are the jet models: The Wooler-Ziegler model, the Fearn-Weston model, and the Thames...rectangular jet model. The " VAPE " program has been applied to a NASA V/STOL model as discussed by Tom. The agreemernt between the calculations and the...properties of the jet are known, this model is intended to calculate surface pressures. It is in the VAPE program as I mentioned earlier. I would like to
20 Years of sea-levels, accretion, and vegetation on two Long ...
The long-term 1939-2013 rate of RSLR (Relative Sea-Level Rise) at the New London, CT tide gauge is ~2.6 mm/yr, near the maximum rate of salt marsh accretion reported in eastern Long Island Sound salt marshes. Consistent with recent literature RSLR at New London has accelerated since the 1980s; inter-annual variability can be high, but over the last three decades rates have averaged ~4.5 mm/yr, more than double the first 40 years of the New London record. Marsh surface elevation has been followed for 10 years with a SET array at the Barn Island system on Little Narragansett Bay and 20 years using an accretion pin array at Mamacoke Marsh on the Thames River. From 2003 – 2013 accretion averaged 2.3 mm/yr on the Barn Island marshes while RSLR increased 5.4 mm/yr. The increased hydroperiod is driving vegetation change at Barn Island, particularly in areas that started with lower “elevation capital”. Over two decades Mamacoke accretion closely matched RSLR: 4.7 vs 4.9 mm/yr, with no significant shifts in vegetation. For the 1st 12 years at Mamacoke, accretion was slower than RSLR: 3.2 vs 8.1 mm/yr. From 2006 to 2014, however elevation increase averaged 7.0 mm/yr while sea level rose just 7 mm. By 2014 accretion rates across the marsh ranged from 1.3 to 16.1 mm /yr. Preliminary core analysis confirms highly organic peat, but reveals sand concentrations at 2–4 cm in some areas, suggesting that Hurricanes Irene (2011) and Sandy (2012) may have contributed to Mama
NASA Astrophysics Data System (ADS)
Ivanov, Evgeny; Capet, Arthur; Barth, Alexander; Delhez, Eric; Soetaert, Karline; Grégoire, Marilaure
2017-04-01
In the frame of the Belgian research project FaCE-It (Functional biodiversity in a Changing sedimentary Environment: Implications for biogeochemistry and food webs in a managerial setting), the impact of dredging activities and offshore wind farm installation on the spatial distribution of sediment grain size, biodiversity and biogeochemistry will be estimated in the Southern Bight of the North Sea (SBNS) with a focus on the Belgian Coastal Zone (BCZ). To reach this goal, the three-dimensional hydrodynamical model ROMS-COAWST is implemented in the SBNS in order to simulate the complex hydrodynamics and sediment transport. Two levels of nesting are used to reach a resolution of 250 m in the BCZ. The model is forced at the air-sea interface by the 6-hourly ECMWF ERA-interim atmospheric dataset and at the open boundaries by the coarse resolution model results available from CMEMS (Copernicus Marine Environment Monitoring Service), and also considers tides and 4 main rivers (Scheldt, Rhine with Maas, Thames and Seine). Two types of simulations have been performed: a 10-years climatological simulation and a simulation over 2003-2013 to investigate the interannual dynamics. The model skills are evaluated by comparing its outputs to historical data (e.g. salinity, temperature and currents) from remote sensing and in-situ. The sediment transport module will then be implemented and its outputs compared to historical and newly collected (in the frame of FaCE-iT) observations on grain size distribution as well as with satellite Suspended Particulate Matter (SPM) images. This will allow assessing the impact of substrate modification due to offshore human activities at local and regional scales.
Hadj-Hammou, Jeneen; Loiselle, Steven; Ophof, Daniel; Thornhill, Ian
2017-01-01
While the role of citizen science in engaging the public and providing large-scale datasets has been demonstrated, the nature of and potential for this science to supplement environmental monitoring efforts by government agencies has not yet been fully explored. To this end, the present study investigates the complementarity of a citizen science programme to agency monitoring of water quality. The Environment Agency (EA) is the governmental public body responsible for, among other duties, managing and monitoring water quality and water resources in England. FreshWater Watch (FWW) is a global citizen science project that supports community monitoring of freshwater quality. FWW and EA data were assessed for their spatio-temporal complementarity by comparing the geographical and seasonal coverage of nitrate (N-NO3) sampling across the River Thames catchment by the respective campaigns between spring 2013 and winter 2015. The analysis reveals that FWW citizen science-collected data complements EA data by filling in both gaps in the spatial and temporal coverage as well as gaps in waterbody type and size. In addition, partial spatio-temporal overlap in sampling efforts by the two actors is discovered, but EA sampling is found to be more consistent than FWW sampling. Statistical analyses indicate that regardless of broader geographical overlap in sampling effort, FWW sampling sites are associated with a lower stream order and water bodies of smaller surface areas than EA sampling sites. FWW also samples more still-water body sites than the EA. As a possible result of such differences in sampling tendencies, nitrate concentrations, a measure of water quality, are lower for FWW sites than EA sites. These findings strongly indicate that citizen science has clear potential to complement agency monitoring efforts by generating information on freshwater ecosystems that would otherwise be under reported.
Loiselle, Steven; Ophof, Daniel; Thornhill, Ian
2017-01-01
While the role of citizen science in engaging the public and providing large-scale datasets has been demonstrated, the nature of and potential for this science to supplement environmental monitoring efforts by government agencies has not yet been fully explored. To this end, the present study investigates the complementarity of a citizen science programme to agency monitoring of water quality. The Environment Agency (EA) is the governmental public body responsible for, among other duties, managing and monitoring water quality and water resources in England. FreshWater Watch (FWW) is a global citizen science project that supports community monitoring of freshwater quality. FWW and EA data were assessed for their spatio-temporal complementarity by comparing the geographical and seasonal coverage of nitrate (N-NO3) sampling across the River Thames catchment by the respective campaigns between spring 2013 and winter 2015. The analysis reveals that FWW citizen science-collected data complements EA data by filling in both gaps in the spatial and temporal coverage as well as gaps in waterbody type and size. In addition, partial spatio-temporal overlap in sampling efforts by the two actors is discovered, but EA sampling is found to be more consistent than FWW sampling. Statistical analyses indicate that regardless of broader geographical overlap in sampling effort, FWW sampling sites are associated with a lower stream order and water bodies of smaller surface areas than EA sampling sites. FWW also samples more still-water body sites than the EA. As a possible result of such differences in sampling tendencies, nitrate concentrations, a measure of water quality, are lower for FWW sites than EA sites. These findings strongly indicate that citizen science has clear potential to complement agency monitoring efforts by generating information on freshwater ecosystems that would otherwise be under reported. PMID:29211752
Sources of greenhouse gases and carbon monoxide in central London (UK)
NASA Astrophysics Data System (ADS)
Helfter, Carole; Tremper, Anja; Zazzeri, Giulia; Barlow, Janet F.; Nemitz, Eiko
2015-04-01
Biosphere-atmosphere exchange of carbon dioxide (CO2) has been on the scientific agenda for several decades and new technology now also allows for high-precision, continuous monitoring of fluxes of methane (CH4) and nitrous oxide (N2O). Compared to the natural environment, flux measurements in the urban environment, which is home to over 50% of the population globally, are still rare despite high densities of anthropogenic sources of pollutants. We report on over three years of measurements atop a 192 m tower in central London (UK), Europe's largest city, which started in October 2011. Fluxes of methane, carbon monoxide (CO) and carbon dioxide are measured by eddy-covariance (EC) at the British Telecom tower (51° 31' 17.4' N 0° 8' 20.04' W). In addition to the long-term measurements, EC fluxes of nitrous oxide (N2O) were measured in February 2014. All four trace gases exhibit diurnal trends consistent with anthropogenic activities with minimum emissions at night and early afternoon maxima. Segregating emissions by wind direction reveals heterogeneous source distributions with temporal patterns and source strengths that differ between compounds. The lowest emissions for CO, CO2 and CH4 were recorded for NW winds. The highest emissions of methane were in the SE sector, in the NE for CO2 and in the W for CO. Fluxes of all 3 gases exhibited marked seasonal trends characterised by a decrease in emissions in summer (63% reduction for CO, 36% for CO2 and 22% for CH4). Monthly fluxes of CO and CO2 were linearly correlated to air temperature (R2 = 0.7 and 0.59 respectively); a weaker dependence upon temperature was also observed for CH4 (R2 = 0.31). Diurnal and seasonal emissions of CO and CO2 are mainly controlled by local fossil fuel combustion and vehicle cold starts are thought to account for 20-30% of additional emissions of CO during the winter. Fugitive emissions of CH4 from the natural gas distribution network are thought to be substantial, which is consistent with the weaker seasonality of CH4 fluxes compared with CO and CO2. Annual estimates of CO2 emissions (41 kt km-2) obtained by EC were consistent with data upscaled from the London Atmospheric Emissions Inventory (LAEI; 46 kt km-2). Good agreement between measurements and inventory data was also found for CO (measured 156 t km-2; LAEI 145 t km-2) and for N2O (measured 0.36 t km-2; LAEI 0.42 t km-2), although based on a much shorter measurement period. By contrast, a two-fold difference was found between inventory and measured CH4 fluxes (measured 75 t km-2; LAEI 34 t km-2), which could indicate an underestimation by the inventory of CH4 emissions from anthropogenic sources or the existence of unaccounted biogenic sources. Measurements of isotopic CH4 taken 2 km SE of the tower near the banks of the river Thames reveal multiple episodes of 13C-depleted morning peaks consistent with biogenic sources. We speculate that the Thames can act as an additional significant source of biogenic methane especially at low tide and after heavy rainfall, which could explain the large emissions observed in the S-SE sector.
Community building - an essential ingredient of the IT infrastructure
NASA Astrophysics Data System (ADS)
Kessler, Holger; Mathers, Steve; Gunnink, Jan
2015-04-01
Many Geological Survey Organisations (GSO) are now building systematic 3D geological models as part of their core programme. Until recently the key players from the GSOs only met occasionally at international conferences and workshops, often in the US during the annual meetings of the Geological Society of America (http://crystal.isgs.uiuc.edu/research/3DWorkshop/index.shtml). After summarising the activities of various leading GSOs in a single document by Berg et al (2010) Synopsis of current three-dimensional geological mapping and modelling in Geological Survey organizations http://nora.nerc.ac.uk/17095/) it was decided in 2013 that more regular meetings should be held in Europe to foster linkages, encourage collaboration, and most importantly share successes and resources and avoid duplication of effort and repetition of mistakes. The initial European 3D Geological Modelling Meeting was hosted by TNO in 2013. The second was held in October 2014 at BGS Edinburgh with 85 staff from 20 GSO's and academic institutions represented. This paper will present the objectives of this community, some outcomes and a plan for the future. As much as good communication between model builders is desirable, it is of course even more essential to have a strong dialogue with the end users, to this end the British Geological Survey recently hosted a well-attended seminar at the Geological Society in London presenting their recently completed geological model of London and the Thames Valley (http://www.bgs.ac.uk/research/ukGeology/nationalGeologicalModel/londonAndThamesValley.html) and the latest web-based delivery mechanism which was designed after extensive consultation with the user community (https://shop.bgs.ac.uk/Groundhog/). Meanwhile in the Netherlands the DINOloket web portal (https://www.dinoloket.nl/) is continuing to adapt to end users needs - the paper will give an update on these and other initiatives.
Lloyd, B W; Becker, D
2007-08-01
To determine what paediatric specialist registrars think of the educational supervision they have received and what advice they would give to a consultant who wanted to be a more effective educational supervisor. A questionnaire study. The North Thames Deanery, UK. 129 year 3, 4 or 5 paediatric specialist registrars in the North Thames Deanery. Reported value of educational supervision on a Likert scale; what elements of educational supervision were reported to be most useful; what elements of educational supervision were reported to be done poorly; what advice would specialist registrars give to a consultant who wanted to be a more effective educational supervisor. 86/129 specialist registrars responded (67%). The mean score on the Likert scale (0-a complete waste of time; 100-excellent) was 57 with 37% of respondents giving a score of less than 50. The most valued aspects of educational supervision were: feedback on performance--cited by 50 respondents (56% of respondents); career advice--cited by 43 (48%); objective setting--cited by 36 (40%); pastoral support--cited by 25 (28%). Aspects of educational supervision that were reported to be often not done well were: commitment to educational supervision--cited by 44 respondents (49% of respondents); ensuring sessions are bleep-free-cited by 43 (48%); listening rather than talking--cited by 23 (26%); being encouraging--cited by 18 (20%). Advice to consultants about how to improve educational supervision included: listen rather than talk; be encouraging; treat the trainee as an individual with individual needs. We can find no other study of trainees' views about how educational supervision can be improved. Although some trainees found educational supervision very valuable, many did not. Educational supervision should only be carried out by consultants who are committed to the task. An educational supervisor should listen carefully in order to understand the trainee's individual ambitions and needs, should provide specific feedback on performance and should be encouraging.
NASA Astrophysics Data System (ADS)
Darling, W. G.; Bath, A. H.; Talbot, J. C.
The utility of stable isotopes as tracers of the water molecule has a long pedigree. The study reported here is part of an attempt to establish a comprehensive isotopic "baseline" for the British Isles as background data for a range of applications. Part 1 of this study (Darling and Talbot, 2003) considered the isotopic composition of rainfall in Britain and Ireland. The present paper is concerned with the composition of surface waters and groundwater. In isotopic terms, surface waters (other than some upland streams) are poorly characterised in the British Isles; their potential variability has yet to be widely used as an aid in hydrological research. In what may be the first study of a major British river, a monthly isotopic record of the upper River Thames during 1998 was obtained. This shows high damping of the isotopic variation compared to that in rainfall over most of the year, though significant fluctuations were seen for the autumn months. Smaller rivers such as the Stour and Darent show a more subdued response to the balance between runoff and baseflow. The relationship between the isotopic composition of rainfall and groundwater is also considered. From a limited database, it appears that whereas Chalk groundwater is a representative mixture of weighted average annual rainfall, for Triassic sandstone groundwater there is a seasonal selection of rainfall biased towards isotopically-depleted winter recharge. This may be primarily the result of physical differences between the infiltration characteristics of rock types, though other factors (vegetation, glacial history) could be involved. In the main, however, groundwaters appear to be representative of bulk rainfall within an error band of 0.5‰ δ18O. Contour maps of the δ18O and δ2H content of recent groundwaters in the British Isles show a fundamental SW-NE depletion effect modified by topography. The range of measured values, while much smaller than those for rainfall, still covers some ‰ for δ18O and 30‰ for δ2H. Over lowland areas the "altitude effect" is of little significance, but in upland areas is consistent with a range of -0.2 to -0.3‰ per 100 m increase in altitude. Groundwaters dating from the late Pleistocene are usually modified in δ18O and δ2H owing to the effects of climate change on the isotopic composition of rainfall and thus of recharge. Contour maps of isotopic variability prior to 10 ka BP, based on the relatively limited information available from the British Isles, allow a first comparison between groundwaters now and at the end of the last Ice Age. The position of the British Isles in the context of the stable isotope systematics of NW Europe is reviewed briefly.
The end of trend-estimation for extreme floods under climate change?
NASA Astrophysics Data System (ADS)
Schulz, Karsten; Bernhardt, Matthias
2016-04-01
An increased risk of flood events is one of the major threats under future climate change conditions. Therefore, many recent studies have investigated trends in flood extreme occurences using historic long-term river discharge data as well as simulations from combined global/regional climate and hydrological models. Severe floods are relatively rare events and the robust estimation of their probability of occurrence requires long time series of data (6). Following a method outlined by the IPCC research community, trends in extreme floods are calculated based on the difference of discharge values exceeding e.g. a 100-year level (Q100) between two 30-year windows, which represents prevailing conditions in a reference and a future time period, respectively. Following this approach, we analysed multiple, synthetically derived 2,000-year trend-free, yearly maximum runoff data generated using three different extreme value distributions (EDV). The parameters were estimated from long term runoff data of four large European watersheds (Danube, Elbe, Rhine, Thames). Both, Q100-values estimated from 30-year moving windows, as well as the subsequently derived trends showed enormous variations with time: for example, estimating the Extreme Value (Gumbel) - distribution for the Danube data, trends of Q100 in the synthetic time-series range from -4,480 to 4,028 m³/s per 100 years (Q100 =10,071m³/s, for reference). Similar results were found when applying other extreme value distributions (Weibull, and log-Normal) to all of the watersheds considered. This variability or "background noise" of estimating trends in flood extremes makes it almost impossible to significantly distinguish any real trend in observed as well as modelled data when such an approach is applied. These uncertainties, even though known in principle are hardly addressed and discussed by the climate change impact community. Any decision making and flood risk management, including the dimensioning of flood protection measures, that is based on such studies might therefore be fundamentally flawed.
Legacy effects of nitrogen and phosphorus in a eutrophic lake catchment: Slapton Ley, SW England
NASA Astrophysics Data System (ADS)
Burt, T. P.; Worrall, F.; Howden, N. J. K.
2017-12-01
Slapton Ley is a freshwater coastal lagoon in SW England. The Ley is part of a National Nature Reserve, which is divided into two basins: the Higher Ley (39 ha) is mainly reed swamp; the Lower Ley (77 ha) is a shallow lake (maximum depth 2.9 m). In the 1960s it became apparent that the Lower Ley was becoming increasingly eutrophic. In order to gauge water, sediment and nutrient inputs into the lake, measurements began on the main catchments in 1969. Continuous monitoring of discharge and a weekly water-sampling programme have been maintained by the Slapton Ley Field Centre ever since. The monitoring programme has been supplemented by a number of research projects which have sought to identify the salient hydrological processes operating within the Slapton catchments and to relate these to the delivery of sediment and solute to the stream system. Long-term monitoring data are also available for the catchment area including the lake from the Environment Agency.The nitrate issue has been of particular interest at Slapton; although many longer series exist for large river basins like the Thames, the long record of nitrate data for the Slapton catchments is unique in Britain for a small rural basin. Recent declines in nitrate concentration may reflect less intensive agricultural activity, lower fertiliser inputs in particular, but there may also be a legacy effect in the shallow groundwater system. Phosphorus concentrations in stream and lake water have also shown declining concentrations but a phosphorus legacy in the surficial lake sediments means that algal blooms continue to develop in most summers, as indicated by a continued rise in summer pH levels. Further field observation at the sediment-water interface is needed to better understand the biogeochemical drivers and the balance between N and P limitation in the lake. Successful management of the Nature Reserve requires better understanding of the links between hydrological and biogeochemical processes operating within the catchment area.
Water resources inventory of Connecticut Part 3: lower Thames and southeastern coastal river basins
Thomas, Chester E.; Cervione, Michael A.; Grossman, I.G.
1968-01-01
The lower Thames and southeastern coastal river basins have a relatively abundant supply of water of generally good quality which is derived from streams entering the area and precipitation that has fallen on the area. Annual precipitation has ranged from about 32 inches to 65 inches and has averaged about 48 inches over a 30-year period. Approximately 22 inches of water are returned to the atmosphere each year by evaporation and transpiration; the remainder of the annual precipitation either flows overland to streams or percolates downward to the water table and ultimately flows out of the report area through estuaries and coastal streams or as underflow through the deposits beneath. During the autumn and winter months precipitation normally is sufficient to cause a substantial increase in the amount of water stored underground and in surface reservoirs within the report area, whereas in the summer most of the precipitation is lost through evaporation and transpiration, resulting in sharply reduced stream-flow and lowered ground-water levels. The mean monthly storage of water on an average is about 3.8 inches higher in November than it is in June. The amount of water that flows through and out of the report area represents the total amount of water potentially available for use by man. For the 30-year period 1931 through 1960, the annual runoff from the report area has averaged nearly 26 inches (200 billion gallons), from the entire Thames River basin above Norwich about 24 inches (530 billion gallons), and from the Pawcatuck River basin about 26 inches (130 billion gallons). A total average annual runoff of 860 billion gallons is therefore available. Although runoff indicates the total amount of water potentially available, it is usually not economically feasible for man to use all of it. On the other hand, with increased development, it is possible that some water will be reused several times. The water available may be tapped as it flows through the area or is temporarily stored in streams, lakes, and aquifers. The amounts that can be developed vary from place to place and time to time, depending on the amount of precipitation, on the size of drainage area, on the thickness, permeability, and areal extent of aquifers, and on the variations in chemical and physical quality of the water. Differences in streamflow from point to point are due primarily to differences in the proportion of stratified drift in the drainage basin above each point, which affect the timing of streamflow, and to differences in precipitation, which affect the amount of streamflow. Ground water can be obtained from wells almost anywhere in the area, but the amount obtainable at any particular point depends upon the type and water-bearing properties of the aquifers. For practical purposes, the earth materials in the report area comprise three aquifers--stratified drift, bedrock, and till. Stratified drift is the only aquifer generally capable of yielding more than 100 gpm (gallons per minute) to individual wells. It covers about 20 percent of the area and occurs chiefly in lowlands where it overlies till and bedrock. The coefficient of permeability of the coarse-grained unit of stratified drift averages about 1,500 gbd (gallons per day) per sq ft. Drilled, screened wells tapping this unit are known to yield from 4 to 88o gpm and average 146 gpm. Dug wells in coarse-grained stratified drift supply about 2 gpm per foot of drawdown over a period of a few hours. Fine-grained stratified drift has an average coefficient of permeability of about 300 gpd per sq ft and can usually yield supplies sufficient for household use to dug wells. Bedrock and till are widespread in extent but generally provide only small water supplies. Bedrock is tapped chiefly by drilled wells, about 90 percent of which will supply at least 3 gpm. Very few, however, will supply more than 50 gpm. Till is tapped in a few places by dug wells which can yield small supplies of only a few hundred gpd throughout all or most of the year. The coefficient of permeability of till ranges from about 0.2 gpd per sq ft to 120 gpd per sq ft. The amount of ground water potentially available in the report area depends upon the amount of ground-water outflow, the amount of ground water in storage, and the quantity of water available by induced infiltration from streams and lakes. From data on permeability, saturated thickness, recharge, yield from aquifer storage, well performance, and streamflow, preliminary estimates of ground-water availability can be made for any point in the report area. Long-term yields estimated for 18 areas of stratified drift especially favorable for development of large ground-water supplies ranged from 1.3 to 66 mgd. Detailed site studies to determine optimum yields, drawdowns, and spacing of individual wells are needed before major ground-water development is undertaken in these or other areas. The chemical quality of water in the report area is generally good to excellent. Samples of naturally occurring surface water collected at 24 sites contained less than 151 ppm (parts per million) of dissolved solids and less than 63 ppm of hardness. Water from wells is more highly mineralized than naturally occurring water from streams. Even so only 12 percent of the wells sampled yielded water with more than 200 ppm of dissolved solids and only 8 percent yielded water with more than 120 ppm of hardness. Even in major streams, which are used to transport industrial waste, hardness rarely exceeds 60 ppm and the dissolved mineral content is generally less than 200 ppm. At a few places in the town of Montville however, waters may contain dissolved mineral concentrations of 2,000 to 4,000 ppm. Iron and manganese in both ground water and surface water are the only constituents whose concentrations commonly exceed recommended limits for domestic and industrial use. Most wells in the report area yield clear water with little or no iron or manganese, but distributed among them are wells yielding ground water that contains enough of these dissolved constituents to be troublesome for most uses. Iron concentrations in naturally occurring stream water exceed 0.3 ppm under low-flow conditions at 33 percent of the sites sampled. Large concentrations of iron in stream water result from discharge of iron-bearing water from aquifers or from swamps where it is released largely from decaying vegetation. Ground water more than 30 feet below the land surface has a relatively constant temperature, usually between 48°F and 52°F. Water temperature in very shallow wells may fluctuate from about 38°F in February or March to about 55°F in late summer. Water temperature in the larger streams fluctuates much more widely, ranging from 32°F at least for brief periods in winter, to about 85°F occasionally during summer. The quality of suspended sediment transported by streams in the area is negligible. Turbidity in streams is generally not a problem although amounts large enough to be troublesome may occur locally at times. The total amount of water used in the report area for all purposes during 1964 was about 118,260 million gallons, of which 105,600 million gallons was estuarine water used for cooling by industry. The average per capita water use, excluding estuarine, temporary summer residence, and institutional water was equivalent to 186 gpd. Public water systems supplied the domestic needs of nearly tw0-thirds the population of the report area. All of the 19 systems, which were sampled, provided water of better quality than the U.S. Public Health Service suggests for drinking water standards.
Identifying Conventionally Sub-Seismic Faults in Polygonal Fault Systems
NASA Astrophysics Data System (ADS)
Fry, C.; Dix, J.
2017-12-01
Polygonal Fault Systems (PFS) are prevalent in hydrocarbon basins globally and represent potential fluid pathways. However the characterization of these pathways is subject to the limitations of conventional 3D seismic imaging; only capable of resolving features on a decametre scale horizontally and metres scale vertically. While outcrop and core examples can identify smaller features, they are limited by the extent of the exposures. The disparity between these scales can allow for smaller faults to be lost in a resolution gap which could mean potential pathways are left unseen. Here the focus is upon PFS from within the London Clay, a common bedrock that is tunnelled into and bears construction foundations for much of London. It is a continuation of the Ieper Clay where PFS were first identified and is found to approach the seafloor within the Outer Thames Estuary. This allows for the direct analysis of PFS surface expressions, via the use of high resolution 1m bathymetric imaging in combination with high resolution seismic imaging. Through use of these datasets surface expressions of over 1500 faults within the London Clay have been identified, with the smallest fault measuring 12m and the largest at 612m in length. The displacements over these faults established from both bathymetric and seismic imaging ranges from 30cm to a couple of metres, scales that would typically be sub-seismic for conventional basin seismic imaging. The orientations and dimensions of the faults within this network have been directly compared to 3D seismic data of the Ieper Clay from the offshore Dutch sector where it exists approximately 1km below the seafloor. These have typical PFS attributes with lengths of hundreds of metres to kilometres and throws of tens of metres, a magnitude larger than those identified in the Outer Thames Estuary. The similar orientations and polygonal patterns within both locations indicates that the smaller faults exist within typical PFS structure but are sub-seismic in conventional imaging techniques. These unseen faults could create additional unseen pathways that impact construction in London via water ingress and influence fluid migration within hydrocarbon basins.
New studies disputing allegations of bacteriological warfare during the Korean War.
Rolicka, M
1995-03-01
In the television series Korea the Unknown War produced jointly by Thames Television (London) and WGBH (Boston) in 1990, General Matthew Ridgway, Commander in Chief of United Nations forces during the Korean War, called the accusations that the United States waged bacteriological warfare "black propaganda." The charges discredited the United States and, despite denials and many international discussions, have not been completely refuted until new. Following studies in archives previously not available for research and after uncovering new sources, many specific examples of black propaganda were discovered that contained false information and lies discrediting the United States. The mechanism of lies, which convinced the Korean population that bacteriological warfare was going on and that the only way not to become victims of the United States' inhuman cruelty was to fight, are shown in this paper.
Biological effects and equivalent doses in radiotherapy: A software solution
Voyant, Cyril; Julian, Daniel; Roustit, Rudy; Biffi, Katia; Lantieri, Céline
2013-01-01
Background The limits of TDF (time, dose, and fractionation) and linear quadratic models have been known for a long time. Medical physicists and physicians are required to provide fast and reliable interpretations regarding delivered doses or any future prescriptions relating to treatment changes. Aim We, therefore, propose a calculation interface under the GNU license to be used for equivalent doses, biological doses, and normal tumor complication probability (Lyman model). Materials and methods The methodology used draws from several sources: the linear-quadratic-linear model of Astrahan, the repopulation effects of Dale, and the prediction of multi-fractionated treatments of Thames. Results and conclusions The results are obtained from an algorithm that minimizes an ad-hoc cost function, and then compared to an equivalent dose computed using standard calculators in seven French radiotherapy centers. PMID:24936319
NASA Astrophysics Data System (ADS)
Basu, N. B.; Van Meter, K. J.
2012-12-01
Increased nutrient loads delivered from watersheds due to agricultural intensification, industrialization, and urbanization have contributed globally to the persistence of large hypoxic zones in inland and coastal waters. Watershed management practices targeting these non-point source pollutants often lead to little or no improvement in water quality, even after extensive implementation of conservation measures or Best Management Practices (BMPs). The lag time between implementation of a conservation measure and resultant water quality benefits has recently been recognized as an important factor in the "apparent" failure of these BMPs. When conservation measures are implemented without explicit consideration of the lag time and with expectations that they will lead to immediate benefits, the resulting failure to meet such expectations can discourage vital restoration efforts. It is therefore important to quantify the lag times associated with watershed management efforts a priori and to implement restoration strategies targeted specifically at minimizing lag times and maximizing restoration benefits. The focus of this research is to develop a framework for understanding the time lags between land-use changes and stream water quality benefits. We hypothesize that such time lags arise from nutrient legacies building over decades of fertilizer application. For nitrogen (N), one can conceptualize this as either hydrologic legacy, in the form of dissolved nitrate that is delayed due to slow groundwater transport, or as biogeochemical legacy, in the form of organic N, possibly in dissolved or readily mineralizable forms. Indeed, mass-balance studies across the Mississippi and Thames river basins indicate the possibility of missing N mass in these landscapes, with inputs being consistently greater than the outputs even when accounting for all possible pathways of nitrogen transformation. Historical soil data within the upper Mississippi River Basin (MRB) indicate that agriculture depletes organic N in surface soil, but leads to N accumulations deeper in the profile. Nitrogen accumulation estimates (approximately 2 million Mt/yr) based on the historical data are startlingly close to the deficit suggested by mass-balance studies of the MRB (3 million Mt/yr). Understanding the lag times associated with such biogeochemical legacies requires quantification of this accumulation as a function of landscape attributes, climate, and management controls, as well as the rate of mineralization of accumulated N after implementation of management practices. Understanding hydrologic legacy requires a partitioning of flow along various pathways (e.g., overland flow, tile flow, or groundwater pathways), and the distribution of travel times along the pathways. Based on this framework, we developed a coupled hydrologic and biogeochemical model to quantify these legacies and predict landscape recovery times as a function of natural and anthropogenic controls.
Can there be fair funding for fundholding practices?
Dixon, J.
1994-01-01
Most regional health authorities set budgets for fundholding practices according to the amount of care used by the practice population. This article explains why this funding method can only lead to an inequitable allocation of resources between fundholding and non-fundholding practices. Using the experience of North West Thames region, the efforts made to make funding fairer are discussed. The steps that health authorities could take to investigate and reduce the problem are also outlined. In the absence of a capitation formula for funding fundholding practices, the paper suggests that health authorities should do much more to investigate the amount of money they spend on non-fundholding practices. Regions could develop and use other methods to set budgets rather than rely on activity recorded by practices. Regions and the Department of Health should resolve urgently if and how far the budgets for fundholders should be compensated for increases in provider prices. Images p773-a PMID:8142835
Joyce, Rachel; Webb, R; Peacock, Janet
2002-11-01
We performed a cross-sectional study of all Thames maternity units, 1994-96, including 540,834 live and stillbirths. In contrast to recent media speculation, no association of caesarean section rates with midwifery staffing levels was found after adjustment for confounders. The only association with staffing was with levels of junior obstetric staffing, which could be a reflection of less experienced management of labour. Caesarean section rates were also associated positively with the levels of delivery beds, which could be a reflection of the closer monitoring of labour that may result from increased bed availability. Both caesarean section and instrumental vaginal delivery rates were associated with epidural rates, which was expected from the literature. Variations in epidural rates were mainly associated with variations in demographic case-mix, due possibly to patient demand. Demographic case-mix was also associated with instrumental vaginal deliveries but not the caesarean section rate.
Comparison of two scores for allocating resources to doctors in deprived areas.
Hutchinson, A; Foy, C; Sandhu, B
1989-11-04
Current proposals in the general practitioner contract include additional payments to doctors working among deprived populations. The underprivileged area score will be used to identify local authority wards with the greatest levels of deprivation, thus acting as the basis for distributing considerable resources. Two methods of identifying deprived populations--the underprivileged area score and the material deprivation score--were compared to determine whether they result in similar allocation of resources to regions. Financial allocations to regions based on figures derived from the contract differed considerably if the material deprivation score was used instead of the underprivileged area score: Northern and Mersey regions gained over 50% of their allocation whereas East Anglia, Oxford, and South West Thames regions lost more than 30% of theirs. Such differences have considerable implications for doctors working among deprived populations as up to 60m pounds each year might be distributed by these payments.
Diagnostic equipment outside the laboratory.
Burrin, J M; Fyffe, J A
1988-01-01
A questionnaire was circulated to clinical biochemistry laboratories in the North West Thames region of the United Kingdom requesting information on extralaboratory equipment. Data on the types and numbers of instruments in use, their relationship with the laboratory, and quality assurance procedures were obtained. Laboratories were prepared to maintain equipment over which they had no responsibility for purchase, training of users, or use. The quality assurance of these instruments gave even greater cause for concern. Although internal quality control procedures were performed on many of the instruments, laboratories were involved in only a minority of these procedures. Quality control procedures and training of users were undertaken on site in less than 50% of blood gas analysers and bilirubin meters and in less than 25% of glucose meters. External quality assessment procedures were non-existent for all of the instruments in use with the exception of glucose stick meters in two laboratories. PMID:3192750
Long-Term Water Quality Studies in a Eutrophic Lake Catchment: Slapton Ley, SW England
NASA Astrophysics Data System (ADS)
Burt, T. P.; Worrall, F.; Howden, N. J. K.
2014-12-01
Monitoring is the process by which we keep the behaviour of the environment in view, an essential way of discovering whether there are significant undesirable changes taking place. Long-term datasets reveal important patterns for scientists to explain and are essential for testing hypotheses undreamt of at the time monitoring scheme was set up. Many environmental processes take place over relatively long periods of time; very often, subtle processes are embedded within highly variable systems so that their weak signal cannot be extracted without a long record. Slapton Ley is a freshwater coastal lagoon in SW England. The Ley is part of a National Nature Reserve, wetland 116 ha in area which is divided into two basins: the Higher Ley (39 ha) is mainly reed swamp; the Lower Ley (77 ha) is open water. In the 1960s it became apparent that the Ley was becoming increasingly eutrophic. In order to gauge water, sediment and nutrient inputs into the lake, measurements began on the main catchments in late 1969. Continuous monitoring of discharge and a weekly water-sampling programme have been maintained by the Slapton Ley Field Centre ever since. The monitoring programme has been supplemented by a number of research projects which have sought to identify the salient hydrological processes operating within the Slapton catchments and to relate these to the delivery of sediment and solute to the stream system. The nitrate issue has been of particular interest at Slapton; although many longer series exist for large rivers like the Thames, the long record of nitrate data for the Slapton catchments is unique in Britain for small rural basins. Other issues to be explored will be the phosphorus legacy in lake sediments and a long-term decline in lake pH. The Slapton water quality record has confirmed that undesirable changes are taking place, revealed evidence of important patterns to be explained, allowed testing of new hypotheses (e.g. links with land-use change) and helped provide strategies for more successful management of the catchment area.
NASA Astrophysics Data System (ADS)
Roe, Helen M.; Coope, G. Russell; Devoy, Robert J. N.; Harrison, Colin J. O.; Penkman, Kirsty E. H.; Preece, Richard C.; Schreve, Danielle C.
2009-11-01
Multidisciplinary investigations of the vegetational, faunal and sea-level history inferred from the infills of buried channels on the coast of eastern Essex have a direct bearing on the differentiation of MIS 11 and MIS 9 in continental records. New data are presented from Cudmore Grove, an important site on Mersea Island that can be linked to the terrace sequence of the River Thames. The vegetational history has been reconstructed from a pollen sequence covering much of the interglacial represented. The temperate nature of the climate is apparent from a range of fossil groups, including plant remains, vertebrates (especially the rich herpetofauna), molluscs and beetles, which all have strong thermophilous components. The beetle data have been used to derive a Mutual Climatic Range reconstruction, suggesting that mean July temperatures were about 2 °C warmer than modern values for southeast England, whereas mean January temperatures may have been slightly colder. The sea-level history has been reconstructed from the molluscs, ostracods and especially the diatoms, which indicate that the marine transgression occurred considerably earlier in the interglacial cycle than at the neighbouring Hoxnian site at Clacton. There are a number of palynological similarities between the sequence at Cudmore Grove and Clacton, especially the presence of Abies and the occurrence of Azolla filiculoides megaspores. Moreover, both sites have yielded Palaeolithic archaeology, indeed the latter is the type site of the Clactonian (flake-and-core) industry. However, the sites can be differentiated on the basis of mammalian biostratigraphy, new aminostratigraphic data, as well as the differences in the sea-level history. The combined evidence suggests that the infill of the channel at Cudmore Grove accumulated during MIS 9, whereas the deposits at Clacton formed during MIS 11. The infill of a much later channel, yielding non-marine molluscs and vertebrates including Hippopotamus, appears to have formed during the Ipswichian (MIS 5e). This evidence is compared with other important sites of late Middle Pleistocene age in Britain and elsewhere on the continent and the importance of a multidisciplinary approach is stressed.
Roe, Helen M.; Coope, G. Russell; Devoy, Robert J.N.; Harrison, Colin J.O.; Penkman, Kirsty E.H.; Preece, Richard C.; Schreve, Danielle C.
2009-01-01
Multidisciplinary investigations of the vegetational, faunal and sea-level history inferred from the infills of buried channels on the coast of eastern Essex have a direct bearing on the differentiation of MIS 11 and MIS 9 in continental records. New data are presented from Cudmore Grove, an important site on Mersea Island that can be linked to the terrace sequence of the River Thames. The vegetational history has been reconstructed from a pollen sequence covering much of the interglacial represented. The temperate nature of the climate is apparent from a range of fossil groups, including plant remains, vertebrates (especially the rich herpetofauna), molluscs and beetles, which all have strong thermophilous components. The beetle data have been used to derive a Mutual Climatic Range reconstruction, suggesting that mean July temperatures were about 2 °C warmer than modern values for southeast England, whereas mean January temperatures may have been slightly colder. The sea-level history has been reconstructed from the molluscs, ostracods and especially the diatoms, which indicate that the marine transgression occurred considerably earlier in the interglacial cycle than at the neighbouring Hoxnian site at Clacton. There are a number of palynological similarities between the sequence at Cudmore Grove and Clacton, especially the presence of Abies and the occurrence of Azolla filiculoides megaspores. Moreover, both sites have yielded Palaeolithic archaeology, indeed the latter is the type site of the Clactonian (flake-and-core) industry. However, the sites can be differentiated on the basis of mammalian biostratigraphy, new aminostratigraphic data, as well as the differences in the sea-level history. The combined evidence suggests that the infill of the channel at Cudmore Grove accumulated during MIS 9, whereas the deposits at Clacton formed during MIS 11. The infill of a much later channel, yielding non-marine molluscs and vertebrates including Hippopotamus, appears to have formed during the Ipswichian (MIS 5e). This evidence is compared with other important sites of late Middle Pleistocene age in Britain and elsewhere on the continent and the importance of a multidisciplinary approach is stressed. PMID:20119485
NASA Technical Reports Server (NTRS)
2003-01-01
For almost 2,000 years, the River Thames has served as the life force of London, capital of the United Kingdom and one of the world's most famous cities. In AD 43 the Romans established the trading settlement of Londinium at a favorable crossing point on the river. The Romans remained until the 5th century, when the city came under Saxon control. The early 17th century saw enormous growth, but the deadly plague of 1664 and 1665 ravaged the population, and in the following year the Great Fire, which burned for four days, destroyed most of the city. A public transportation system and other city services in the early 19th century eased many of the increasing urban problems of the burgeoning capital of the wealthy British Empire. After coping with the devastating effects of bombing during World War II and the gradual dismantling of the empire, London today thrives as a vital modern metropolis. London is one of 100 cities being studied using ASTER data to map and monitor urban use patterns and growth.This image was acquired on October 12, 2001 by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA's Terra satellite. With its 14 spectral bands from the visible to the thermal infrared wavelength region, and its high spatial resolution of 15 to 90 meters (about 50 to 300 feet), ASTER images Earth to map and monitor the changing surface of our planet.ASTER is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of Economy, Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products.The broad spectral coverage and high spectral resolution of ASTER will provide scientists in numerous disciplines with critical information for surface mapping, and monitoring of dynamic conditions and temporal change. Example applications are: monitoring glacial advances and retreats; monitoring potentially active volcanoes; identifying crop stress; determining cloud morphology and physical properties; wetlands evaluation; thermal pollution monitoring; coral reef degradation; surface temperature mapping of soils and geology; and measuring surface heat balance.Dr. Anne Kahle at NASA's Jet Propulsion Laboratory, Pasadena, California, is the U.S. Science team leader; Bjorn Eng of JPL is the project manager. The Terra mission is part of NASA's Earth Science Enterprise, a long- term research effort to understand and protect our home planet. Through the study of Earth, NASA will help to provide sound science to policy and economic decision-makers so as to better life here, while developing the technologies needed to explore the universe and search for life beyond our home planet.Size: 39.5 x 55.3 km (24.5 x 34.3 miles) Location: 51.5 deg. North lat., 0.1 deg. West long. Orientation: North at top Image Data: ASTER bands 1,2, and 3. Original Data Resolution: 15 m Date Acquired: October 12, 2001Review of child development teams.
Zahir, M; Bennett, S
1994-01-01
Since the Court report was published in 1976 there has been a consensus that the needs of children with disabilities are best met by child development teams. This study explored the structure, facilities, and organisational elements of child development teams operating in the South East Thames region by means of a structured interview with senior professionals involved with organising services for children with disabilities in 14 of 15 health districts in the region. Although all districts had a designated child development team, not all core professionals were adequately represented and four of 14 districts had no child development centre. The quality of buildings and facilities was variable. Teams that did not have a physical base in the form of a centre had fewer staff in the service and poorer facilities. There is a need for further consensus work about broad guidelines on the requirements of child development teams. These will help to inform purchasing authorities about the needs of children with disabilities living in their districts. PMID:8135568
Management of colorectal cancer in three South Thames District Health Authorities.
Pollock, A M; Vickers, N
1997-05-01
This study describes the management of colorectal cancer, diagnosed in 1988, of residents in three South Thames Districts. Of the 328 cases identified as having being diagnosed in 1988, case notes were retrieved on 263 (80%) including 62 registered by death certificate only. There were 159 cases (61%) of colon cancer and 104 cases (39%) of rectal cancer. Of these, 172 cases (68%) were admitted electively and 90 (32%) as emergencies. Patients subsequently diagnosed with colon cancer had a relative risk of being admitted through emergency (relative to rectal cancer patients) of 1.39 (95% C.I.: 1.16, 1.67). Elective admissions varied significantly by district of residence (P < 0.0001) ranging from 36-65% for colon cancers and from 63-92% for rectal cancers across the three districts. Dukes' stage was recorded in only 143 (54%) sets of case notes, with significant variation by district of residence in the proportion of elective patients for whom a Dukes' stage was indicated (P < 0.01). Two-hundred and thirty-six (90%) cases received treatment. Of the treated cases, 233 patients received surgery with 29 cases of colon cancer (18%) and 32 cases of rectal cancer (31%) receiving adjuvant therapy. The proportions of anterior resection, AP resection and colostomies given, varied by district. Patients presenting for elective surgery were more likely to be treated by a consultant than patients presenting on emergency: the relative risks were 2.58 (95% C.I.: 1.74, 3.82) for colon cancer patients and 4.93 (95% C.I.: 2.20, 11.06) for rectal cancer patients. In 44 (26%) colon cancer cases and 21 (22%) rectal cancer cases it was explicitly stated that the tumour had not been fully resected. For colon tumours the five year relative survival rates were 35% (95% C.I.: 21%, 50%), 52% (95% C.I.: 34%, 70%), and 14% (95% C.I.: -2%, 30%) in districts A, B and C respectively. The corresponding figures for rectal tumours were 45% (95% C.I.: 27%, 64%), 62% (95% C.I.: 41%, 83%) and 24% (95% C.I.: -1%, 50%). There were wide variations in the representation, management of and survival from colorectal cancers across the three districts. Differences were significant at the level of district of residence, mode of presentation and surgical grade. More assiduous recording of Dukes' stage is imperative if consensus is to be achieved on effective management. Further work is also warranted on district differences in diagnostic and referral protocols.
Ecohydrological controls over water budgets in floodplain meadows
NASA Astrophysics Data System (ADS)
Morris, Paul J.; Verhoef, Anne; Macdonald, David M. J.; Gardner, Cate M.; Punalekar, Suvarna M.; Tatarenko, Irina; Gowing, David
2013-04-01
Floodplain meadows are important ecosystems, characterised by high plant species richness including rare species. Fine-scale partitioning along soil hydrological gradients allows many species to co-exist. Concerns exist that even modest changes to soil hydrological regime as a result of changes in management or climate may endanger floodplain meadows communities. As such, understanding the interaction between biological and physical controls over floodplain meadow water budgets is important to understanding their likely vulnerability or resilience. Floodplain meadow plant communities are highly heterogeneous, leading to patchy landscapes with distinct vegetation. However, it is unclear whether this patchiness in plant distribution is likely to translate into heterogeneous soil-vegetation-atmosphere transfer (SVAT) rates of water and heat, or whether floodplain meadows can reasonably be treated as internally homogeneous in physical terms despite this patchy vegetation. We used a SVAT model, the Soil-Water-Atmosphere-Plants (SWAP) model by J.C. van Dam and co-workers, to explore the controls over the partitioning of water budgets in floodplain meadows. We conducted our research at Yarnton Mead on the River Thames in Oxfordshire, one of the UK's best remaining examples of a floodplain meadow, and which is still managed and farmed in a low-intensity mixed-use manner. We used soil and plant data from our site to parameterise SWAP; we drove the model using in-situ half-hourly meteorological data. We analysed the model's sensitivity to a range of soil and plant parameters - informed by our measurements - in order to assess the effects of different plant communities on SVAT fluxes. We used a novel method to simulate water-table dynamics at the site; the simulated water tables provide a lower boundary condition for SWAP's hydrological submodel. We adjusted the water-table model's parameters so as to represent areas of the mead with contrasting topography, and so different heights above the river level and different moisture and drainage regimes. The model was most sensitive to changes in the parameters that define the water-table model. Plant above-ground parameters, such as leaf area index and canopy height also had strong influences on simulated fluxes. The model exhibited low sensitivity to plant root parameters; this was particularly true during wet periods when the simulated plant communities were oxygen stressed. Changes in soil texture profile exhibited an intermediate level of control over SVAT fluxes. Our findings indicate that unlike in environments with deep water tables, such as drylands and headwater basins, high-quality water-table data with decimetre or even centimetre accuracy are important to accurate simulation of SVAT fluxes. Future studies that seek to simulate SVAT fluxes in shallow groundwater systems should either use high frequency, high-quality water-table observations as part of the driving data set, or should ensure that water-table dynamics and their interactions with surface processes can be simulated in a robust and physically meaningful manner. The low sensitivity of our model to plant root parameters reflects the proximity of the water table to the ground surface and the fact that the simulated plant community is rarely water-stressed, and again contrasts with findings from existing SVAT model research in environments with deep water tables.
NASA Astrophysics Data System (ADS)
Roxburgh, Ian W.
2007-12-01
Hermann Bondi was an Applied Mathematician of distinction who will be remembered by fellow scientists for his outstanding contributions to astronomy, cosmology and General Relativity, and particularly for his pioneering contributions to our understanding of gravitational waves, his foundational work on accretion, and as co-creator with Tommy Gold and Fred Hoyle of the steady state theory of cosmology. But Hermann had an equally important second career in scientific administration: advising the UK Government on the Thames Barrier, as Director General of the European Space Research Organisation (ESRO; now the European Space Agency (ESA)), as Chief Scientific Advisor to the UK Government on Defence and then on Energy, as Chairman of the Natural Environmental Research Council (NERC), and finally as Master of Churchill College, Cambridge. He was knighted in 1973. He continued his research on gravitational radiation throughout his administrative career and published his 16th paper in the series on gravitational waves in 2004. Hermann will be remembered not only for his contributions to science and administration, but for his outstanding communication skills and as a charismatic, warm, and stimulating person.
NASA Astrophysics Data System (ADS)
Leavy, Aisling
2015-09-01
In the evolving field of mathematics education, there is the need to maintain the relationship between what is presented in college level preparation courses and the skills required to teach mathematics in classrooms. This research examines the knowledge demands placed on 73 pre-service primary teachers as they use lesson study to plan and teach data handling in primary classrooms. Pre-service teachers are observed as they plan, teach and re-teach data lessons in classrooms. Problems of practice are identified and categorized using the Ball, Thames and Phelps (2008) subdomains of common content knowledge (CCK), specialized content knowledge (SCK), knowledge of content and students (KCS) and knowledge of content and teaching (KCT). The results provide insights into the specific knowledge demands placed on early career teachers when teaching data and statistics and identifies foci area that can be addressed in teacher preparation programs. The results illustrate that development of understandings in one knowledge subdomain can motivate and impact learning in another subdomain. These interrelationships were found to exist both within and between the domains of content and pedagogical content knowledge.
MORTIMER, P. P.
2008-01-01
SUMMARY The efforts of the Metropolitan Asylums Board in Victorian London to isolate cases of smallpox in hospitals, and so limit its spread, set off a controversy about ‘hospital influence’, i.e. alleged escapes of the disease into the neighbourhood. When, in 1870, the Board began to gather cases of smallpox into its new intra-urban isolation hospitals, nearby householders resisted, and in 1881 their fear of aerial transmission was endorsed by a government medical inspector, W. H. Power. Not all agreed with Power, but as a result from 1885 the Board removed almost all known cases of smallpox in London to hospital ships moored in the Thames Estuary. The ships failed to provide adequate and secure accommodation, however, and so Board smallpox hospitals were erected on the adjacent Dartford marshes. After 1903, there being no more smallpox epidemics in Britain, these isolation hospitals and many similar ones outside other towns and cities were little used for their main intended purpose. Their retention for many years thereafter can be seen as an application of the precautionary principle; it bears on current contingency plans in Britain and elsewhere for dealing with serious epidemics. PMID:18325128
Challenges in investigating transient rash illness in nursery children.
Paranthaman, K; Pooransingh, S; McCarthy, N; Saunders, P; Haworth, E
2010-06-01
In October 2007, the Thames Valley Health Protection Unit (TVHPU) was notified by a parent that her child developed a transient rash after eating lunch at a nursery in Oxfordshire. An initial investigation undertaken by TVHPU was escalated when similar incidents were reported in nurseries in other parts of England. A detailed epidemiological and food tracing investigation was conducted to ascertain the aetiology. Investigations revealed 11 incidents affecting 164 children between July and November 2007 in six nurseries operated by two companies. The symptoms included a transient rash around the mouth and hands of children who ate meals prepared on site by the nurseries. Consumption of the lunch main course appeared to be a strong aetiological factor. Expert opinion pointed to biogenic amines (e.g. histamine) as a possible cause for the symptoms displayed, but there was insufficient evidence to support testing of food samples. The incident highlighted significant gaps in reporting of unexplained symptoms among children in nurseries, indicating that such incidents do not always come to the attention of public health authorities. Timely notification to HPUs will enable prompt investigation, increase the likelihood of identifying the cause and inform appropriate responses to prevent future incidents.
NASA Astrophysics Data System (ADS)
Matrosov, E.; Padula, S.; Huskova, I.; Harou, J. J.
2012-12-01
Population growth and the threat of drier or changed climates are likely to increase water scarcity world-wide. A combination of demand management (water conservation) and new supply infrastructure is often needed to meet future projected demands. In this case system planners must decide what to implement, when and at what capacity. Choices can range from infrastructure to policies or a mix of the two, culminating in a complex planning problem. Decision making under uncertainty frameworks can be used to help planners with this planning problem. This presentation introduces, applies and compares four decision making under uncertainty frameworks. The application is to the Thames basin water resource system which includes the city of London. The approaches covered here include least-economic cost capacity expansion optimization (EO), Robust Decision Making (RDM), Info-Gap Decision Theory (Info-gap) and many-objective evolutionary optimization (MOEO). EO searches for the least-economic cost program, i.e. the timing, sizing, and choice of supply-demand management actions/upgrades which meet projected water demands. Instead of striving for optimality, the RDM and Info-gap approaches help build plans that are robust to 'deep' uncertainty in future conditions. The MOEO framework considers multiple performance criteria and uses water systems simulators as a function evaluator for the evolutionary algorithm. Visualizations show Pareto approximate tradeoffs between multiple objectives. In this presentation we detail the application of each framework to the Thames basin (including London) water resource planning problem. Supply and demand options are proposed by the major water companies in the basin. We apply the EO method using a 29 year time horizon and an annual time step considering capital, operating (fixed and variable), social and environmental costs. The method considers all plausible combinations of supply and conservation schemes and capacities proposed by water companies and generates the least-economic cost annual plan. The RDM application uses stochastic simulation under a weekly time-step and regret analysis to choose a candidate strategy. We then use a statistical cluster algorithm to identify future states of the world under which the strategy is vulnerable. The method explicitly considers the effects of uncertainty in supply, demands and energy price on multiple performance criteria. The Info-gap approach produces robustness and opportuneness plots that show the performance of different plans under the most dire and favorable sets of future conditions. The same simulator, supply and demand options and uncertainties are considered as in the RDM application. The MOEO application considers many more combinations of supply and demand options while still employing a simulator that enables a more realistic representation of the physical system and operating rules. A computer cluster is employed to ease the computational burden. Visualization software allows decision makers to interactively view tradeoffs in many dimensions. Benefits and limitations of each framework are discussed and recommendations for future planning in the basin are provided.
Yeung, Thomas; Bates, Tony
2004-03-01
Since the publication of "Sustainable Communities--building for the future", Government attention has focused largely on high-density affordable housing in the four "growth areas": Thames Gateway; Ashford; Milton Keynes--South Midlands, and London--Stansted--Cambridge. In this article, Thomas Yeung and Tony Bates suggest that a greater and more sustainable impact would be achieved if architects, planners, and developers considered the potential for community-based water and waste management and on-site energy generation and distribution right from the start of the project. In particular, they consider that the communal nature of hospitals, universities, and public/community housing provides a great opportunity for on-site renewable CHP and/or distributed heating, which could combine global environmental benefits with improved local amenities. They describe a simple model for prioritising energy management in the built environment, and draw on lessons learnt at ETRCL in Dagenham and BedZED in Surrey to offer a few recommendations for Government and developers. Tony Bates is the business development manager for Scott Wilson in the South East and is responsible for the promotion of sustainable communities through relationships with architects, developers, land owners and local authorities. Thomas Yeung leads the Energy Infrastructure Technologies group in Scott Wilson. This team offers an integrated approach to clean community-based energy generation, energy management, waste and water management, sustainable transport, and sustainable buildings/communities.
NASA Astrophysics Data System (ADS)
El Hattab, M. H.; Vernon, D.; Mijic, A.
2017-12-01
Low impact development practices (LID) are deemed to have a synergetic effect in mitigating urban storm water flooding. Designing and implementing effective LID practices require reliable real-life data about their performance in different applications; however, there are limited studies providing such data. In this study an innovative micro-monitoring system to assess the performance of porous pavement and rain gardens as retrofitting technologies was developed. Three pilot streets in London, UK were selected as part of Thames Water Utilities Limited's Counters Creek scheme. The system includes a V-notch weir installed at the outlet of each LID device to provide an accurate and reliable quantification over a wide range of discharges. In addition to, a low flow sensor installed downstream of the V-notch to cross-check the readings. Having a flow survey time-series of the pre-retrofitting conditions from the study streets, extensive laboratory calibrations under different flow conditions depicting the exact site conditions were performed prior to installing the devices in the field. The micro-monitoring system is well suited for high-resolution temporal monitoring and enables accurate long-term evaluation of LID components' performance. Initial results from the field validated the robustness of the system in fulfilling its requirements.
Deglaciation of the Eurasian ice sheet complex
NASA Astrophysics Data System (ADS)
Patton, Henry; Hubbard, Alun; Andreassen, Karin; Auriac, Amandine; Whitehouse, Pippa L.; Stroeven, Arjen P.; Shackleton, Calvin; Winsborrow, Monica; Heyman, Jakob; Hall, Adrian M.
2017-08-01
The Eurasian ice sheet complex (EISC) was the third largest ice mass during the Last Glacial Maximum with a span of over 4500 km and responsible for around 20 m of eustatic sea-level lowering. Whilst recent terrestrial and marine empirical insights have improved understanding of the chronology, pattern and rates of retreat of this vast ice sheet, a concerted attempt to model the deglaciation of the EISC honouring these new constraints is conspicuously lacking. Here, we apply a first-order, thermomechanical ice sheet model, validated against a diverse suite of empirical data, to investigate the retreat of the EISC after 23 ka BP, directly extending the work of Patton et al. (2016) who modelled the build-up to its maximum extent. Retreat of the ice sheet complex was highly asynchronous, reflecting contrasting regional sensitivities to climate forcing, oceanic influence, and internal dynamics. Most rapid retreat was experienced across the Barents Sea sector after 17.8 ka BP when this marine-based ice sheet disintegrated at a rate of ∼670 gigatonnes per year (Gt a-1) through enhanced calving and interior dynamic thinning, driven by oceanic/atmospheric warming and exacerbated by eustatic sea-level rise. From 14.9 to 12.9 ka BP the EISC lost on average 750 Gt a-1, peaking at rates >3000 Gt a-1, roughly equally partitioned between surface melt and dynamic losses, and potentially contributing up to 2.5 m to global sea-level rise during Meltwater Pulse 1A. Independent glacio-isostatic modelling constrained by an extensive inventory of relative sea-level change corroborates our ice sheet loading history of the Barents Sea sector. Subglacial conditions were predominately temperate during deglaciation, with over 6000 subglacial lakes predicted along with an extensive subglacial drainage network. Moreover, the maximum EISC and its isostatic footprint had a profound impact on the proglacial hydrological network, forming the Fleuve Manche mega-catchment which had an area of ∼2.5 × 106 km2 and drained the present day Vistula, Elbe, Rhine and Thames rivers through the Seine Estuary. During the Bølling/Allerød oscillation after c. 14.6 ka BP, two major proglacial lakes formed in the Baltic and White seas, buffering meltwater pulses from eastern Fennoscandia through to the Younger Dryas when these massive proglacial freshwater lakes flooded into the North Atlantic Ocean. Deglaciation temporarily abated during the Younger Dryas stadial at 12.9 ka BP, when remnant ice across Svalbard, Franz Josef Land, Novaya Zemlya, Fennoscandia and Scotland experienced a short-lived but dynamic re-advance. The final stage of deglaciation converged on present day ice cover around the Scandes mountains and the Barents Sea by 8.7 ka BP, although the phase-lagged isostatic recovery still continues today.
NASA Astrophysics Data System (ADS)
O'Shea, Francis; Spencer, Kate; Brasington, James
2014-05-01
Historically, waste was deposited on low value, easily accessible coastal land (e.g. marsh land). Within England and Wales alone, there are over 5000 historical landfills situated within coastal areas at risk of flooding at a 1 in 100 year return period (Environment Agency, 2012). Historical sites were constructed prior to relevant legislation, and have no basal or side wall engineering, and the waste constituents are mostly unknown. In theory, contaminant concentrations should be reduced through natural attenuation as the leachate plume migrates through surrounding fine-grained inter-tidal sediments before reaching receptor waters. However, erosion resulting from rising sea level and increased storm intensity may re-distribute these sediments and release associated contaminants into the estuarine and coastal environment. The diffuse discharge from these sites has not been quantified and this presents a problem for those landfill managers who are required to complete EIAs. An earlier detailed field campaign at Newlands landfill site, on the Thames Estuary, UK identified a sub-surface (~2m depth) contaminant plume extending c. 20 m from the landfill boundary into surrounding fine-grained saltmarsh sediments. These saltmarsh sediments are risk of being eroded releasing their contaminant load to the Thames Estuary. The aims of this work were to; 1) assess whether this plume is representative of other historical landfills with similar characteristics and 2) to develop a rapid screening methodology using field portable XRF that could be used to identify potential risk of other coastal landfill sites. GIS was used to select landfill sites of similar age, hydrological regime and sedimentary setting in the UK, for comparison. Collection of sediment samples and analysis by ICP OES is expensive and time-consuming, therefore cores were extracted and analysed with a Niton Goldd XRF in-situ. Contaminant data were available immediately and the sampling strategy could be adapted in the field to determine the presence, location and extent of the sub-surface contaminant plume. Although XRF analysis has gained acceptance in the study of in-situ metal contamination (Kalnicky and Singhvi 2001; Martin Peinado et al. 2010) field moisture content and sample heterogeneity can suppress X-ray signals. Therefore, sediment samples were also collected and returned to the laboratory and analysed by ICP OES for comparison. Both wet and dry certified reference materials were also analysed in the laboratory using XRF and ICP OES to observe the impact of moisture content and to produce a correction factor allowing quantitative data to be collected in the field. In-situ raw XRF data identified the location of contamination plumes in the field in agreement with ICP data, although the data were systematically suppressed compared to ICP data, under-estimating the levels of contamination. Applying a correction factor for moisture content provided accurate measurements of concentration. The use of field portable XRF with the application of a moisture content correction factor enables the rapid screening of sediment fronting coastal landfill sites, goes some way towards providing a national baseline dataset and can contribute to the development of risk assessments.
NASA Astrophysics Data System (ADS)
Beerten, Koen; Leterme, Bertrand
2013-04-01
From a geodynamic point of view, the Campine area is situated on the crossroads between distinctive tectonic settings: the subsiding North Sea basin and Roer Valley Graben in the north, and the uplifting Brabant Massif and Ardennes in the south. In general, this has led to overall Cenozoic subsidence of the area and sedimentation of unconsolidated marine sands. However, the morphology of the present-day Nete basin, which is situated in the central and eastern part of the Campine area, is a clear example of an erosional feature and shows evidence of up to 30 m of Quaternary erosion. However, the drivers, timing and rate of landscape development in the Nete basin are poorly constrained. Here, we present and describe geological and geomorphological remnants testifying to past landscape development in the Nete basin, that will help understanding the Quaternary geodynamic evolution (uplift) of the Campine area. The Nete basin is located in northern Belgium and is drained by two small rivers, the Kleine Nete and Grote Nete, that merge into the larger Nete river several km before entering the Lower Scheldt basin. The Nete basin can clearly be identified on topographical maps as a depression, ca. 40 km x 40 km, with valley floors ranging between 10-20 m above sea level (a.s.l.). It is bounded in the north, east and south by erosion resistant geological formations at altitudes between 30 m (north) and 60 m (south). The major direction of drainage is from ENE to WSW and the basin thus opens towards the west. The start of basin development is situated after deposition of Rhine sediments (~ 1 Ma) which form the erosion resistant eastern watershed with the Meuse basin at an altitude of ~ 50 m a.s.l. on top of the Campine Plateau. GIS-based landscape analysis of the topography and the contour map of the Quaternary base confirm the observation that the lowering of the relief from the Campine Plateau down to the floodplain of the Kleine Nete and Grote Nete shows a stepwise appearance. Hitherto, 7 levels have been identified, at ~ 42 m, ~ 37 m, ~ 33 m, ~ 28 m, ~ 24 m, ~ 19 m and ~ 17 m (a.s.l.). These surfaces are sometimes very well preserved and may represent erosional terraces (of an old S-N flowing river) or pediment remnants, according to the very thin Quaternary deposits preserved there. In other cases, substantially thick Quaternary deposits (2-3 m) are associated with such surfaces. For example, the level at ~ 33 m is associated with sediments which are indicated as 'Pleistocene of the river valleys' on the geological map, suggesting a fluvial origin for these deposits at an intermediate altitude between the Campine Plateau and the Nete valley. The upper three levels are believed to have been formed in a drainage basin with consequent flow in northern direction, while the lower levels very likely correspond to a drainage network that already adapted to the underlying geological structure. The upper three levels are tentatively assigned to the period during which the Campine Plateau experienced significant uplift and tilting together with the northern Ardennes (van Balen et al., 2000; Westaway, 2001), i.e. between 0.4-0.8 Ma. The lower levels are believed to have been formed primarily in response to base level lowering following major sea level lowstand basin changes in the southern North Sea and the English Channel in the time period after ~ 0.4 Ma (Toucanne et al., 2009; Hijma et al., 2012). In future work, cosmogenic nuclide dating and optically stimulated luminescence dating of exposed and/or buried sediments will be applied in order to verify this hypothesis. Acknowledgments This work is performed in close cooperation with, and with the financial support of ONDRAF/NIRAS, the Belgian Agency for Radioactive Waste and Fissile Materials, as part of the programme on geological disposal of high-level/long-lived radioactive waste that is carried out by ONDRAF/NIRAS. The views expressed in the abstract do not necessarily correspond to those of ONDRAF/NIRAS. References Hijma, M.P., Cohen, K.M., Roebroeks, W., Westerhoff, W.E., Busschers, F.S., 2012. Pleistocene Rhine-Thames landscapes: geological background for hominin occupation of the southern North Sea region. Journal of Quaternary Science, 27, 17-39. Toucanne, S., Zaragosi, S., Bourillet, J.F., Gibbard, P.L., Eynaud, F., Giraudeau, J., Turon, J.L., Cremer, M., Cortijo, E., Martinez, P., Rossignol, L., 2009. A 1.2 Ma record of glaciation and fluvial discharge from the Western European Atlantic margin. Quaternary Science Reviews, 28, 2974-2981. van Balen, R.T., Houtgast, R.F., Van der Wateren, F.M., Vandenberghe, J., Bogaart, P.W., 2000. Sediment budget and tectonic evolution of the Meuse catchment in the Ardennes and the Roer Valley Rift System. Global and Planetary Change, 27, 113-129. Westaway, 2001. Flow in the lower continental crust as a mechanism for the Quaternary uplift of the Rhenish Massif, north-west Europe. In: Maddy, D., Macklin, M.G. & Woodward, J.C. (eds) River Basin Sediment Systems: Archives of Environmental Change. Balkema (Rotterdam), 87-167.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Delaware Bay and River, Salem River, Christina River and Schuylkill River-Regulated Navigation Area. 165.510 Section 165.510... Limited Access Areas Fifth Coast Guard District § 165.510 Delaware Bay and River, Salem River, Christina...
Code of Federal Regulations, 2012 CFR
2012-07-01
... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Delaware Bay and River, Salem River, Christina River and Schuylkill River-Regulated Navigation Area. 165.510 Section 165.510... Limited Access Areas Fifth Coast Guard District § 165.510 Delaware Bay and River, Salem River, Christina...
A multi-criteria targeting approach to neutral grassland conservation.
Bayliss, Julian; Helyar, Alice; Lee, John T; Thompson, Stewart
2003-02-01
Resources for creating and managing rare habitats are limited, and a targeting approach aimed at identifying the most viable sites for habitat conservation is therefore desirable. This study developed a multi-criteria targeting approach to site conservation for two rare grassland types, based on a suite of biotic and abiotic factors managed within a Geographical Information System. A number of biotic and abiotic criteria were assessed to evaluate the biodiversity status of grassland sites. Biotic factors included species diversity, species richness and species rarity; and abiotic factors included patch area, position in the ecological unit and the influence of surrounding land use. Each criterion was given equal weighting and a final biodiversity value for each patch was calculated; the patch with the highest cumulative rank score was deemed the patch with the greatest biodiversity. Each site was then examined in relation to agricultural land under the existing management prescriptions of the Upper Thames Tributaries Environmentally Sensitive Area (UTTESA). Sites identified with high biodiversity potential, but currently not included under management prescriptions, were targeted for future inclusion in the ESA scheme. The targeting approach demonstrated how the national Lowland Meadows habitat action plan creation target of 500 ha could be achieved in the UTTESA. The fact that this target figure was so easily attained within this study area highlighted the possible underestimation of national habitat creation targets.
Brinker, Andrea; Prior, Kate; Schumacher, Jan
2009-01-01
The threat of mass casualties caused by an unconventional terrorist attack is a challenge for the public health system, with special implications for emergency medicine, anesthesia, and intensive care. Advanced life support of patients injured by chemical or biological warfare agents requires an adequate level of personal protection. The aim of this study was to evaluate the personal protection knowledge of emergency physicians and anesthetists who would be at the frontline of the initial health response to a chemical/biological warfare agent incident. After institutional review board approval, knowledge of personal protection measures among emergency medicine (n = 28) and anesthetics (n = 47) specialty registrars in the South Thames Region of the United Kingdom was surveyed using a standardized questionnaire. Participants were asked for the recommended level of personal protection if a chemical/biological warfare agent(s) casualty required advanced life support in the designated hospital resuscitation area. The best awareness within both groups was regarding severe acute respiratory syndrome, and fair knowledge was found regarding anthrax, plague, Ebola, and smallpox. In both groups, knowledge about personal protection requirements against chemical warfare agents was limited. Knowledge about personal protection measures for biological agents was acceptable, but was limited for chemical warfare agents. The results highlight the need to improve training and education regarding personal protection measures for medical first receivers.
The ecohealth assessment and ecological restoration division of urban water system in Beijing
Liu, J.; Ma, M.; Zhang, F.; Yang, Z.; Domagalski, Joseph L.
2009-01-01
Evaluating six main rivers and six lakes in Beihuan water system (BWS) and diagnosing the limiting factors of eco-health were conducted for the ecohealth assessment and ecological restoration division of urban water system (UWS) for Beijing. The results indicated that Jingmi River and Nanchang River were in a healthy state, the degree of membership to unhealthy were 0.358, 0.392, respectively; while Yongding River, Beihucheng River, Liangma River, Tongzi River and six lakes were in an unhealthy state, their degree of membership to unhealthy were between 0.459 and 0.927. The order of that was Liangma > Beihucheng > Tongzi > Yongding > six lakes > Jingmi > Nanchang, in which Liangma Rivers of that was over 0.8. The problems of Rivers and lakes in BWS are different. Jingmi River and Nanchang River were ecotype limiting; Yongding River, Tongzi River and six lakes were water quality and ecotype limiting. Beihucheng River and Liangma River were water quantity, water quality and ecotype limiting. BWS could be divided into 3 restoration divisions, pollution control division including Yongding River, Tongzi River and six lakes; Jingmi River and Nanchang River were ecological restoration zone, while Beihucheng River and Liangma River were in comprehensive improvement zone. Restoration potentiality of Jingmi River and Nanchang River were higher, and Liangma River was hardest to restore. The results suggest a new idea to evaluate the impact of human and environmental factors on UWS. ?? Springer Science+Business Media, LLC 2009.
Evaluate Status of Pacific Lamprey in the Clearwater River Drainage, Idaho, Annual Report 2002.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cochnauer, Tim; Claire, Christopher
In 2002 Idaho Department of Fish and Game continued investigation into the status of Pacific lamprey populations in Idaho's Clearwater River drainage. Trapping, electrofishing, and spawning ground redd surveys were used to determine Pacific lamprey distribution, life history strategies, and habitat requirements in the South Fork Clearwater River, Lochsa River, Selway River, and Middle Fork Clearwater River subbasins. Five-hundred forty-one ammocoetes were captured electroshocking 70 sites in the South Fork Clearwater River, Lochsa River, Selway River, Middle Fork Clearwater River, Clearwater River, and their tributaries in 2002. Habitat utilization surveys in Red River support previous work indicating Pacific lamprey ammocoetemore » densities are greater in lateral scour pool habitats compared to riffles and rapids. Presence-absence survey findings in 2002 augmented 2000 and 2001 indicating Pacific lamprey macrothalmia and ammocoetes are not numerous or widely distributed. Pacific lamprey distribution was confined to the lower reaches of Red River below rkm 8.0, the South Fork Clearwater River, Lochsa River (Ginger Creek to mouth), Selway River (Race Creek to mouth), Middle Fork Clearwater River, and the Clearwater River (downstream to Potlatch River).« less
Code of Federal Regulations, 2012 CFR
2012-10-01
... salmon, Snake River fall chinook salmon, and Snake River spring/summer chinook salmon. 226.205 Section... Snake River sockeye salmon, Snake River fall chinook salmon, and Snake River spring/summer chinook... River salmon (except reaches above impassable natural falls, and Dworshak and Hells Canyon Dams...
Code of Federal Regulations, 2013 CFR
2013-10-01
... salmon, Snake River fall chinook salmon, and Snake River spring/summer chinook salmon. 226.205 Section... Snake River sockeye salmon, Snake River fall chinook salmon, and Snake River spring/summer chinook... River salmon (except reaches above impassable natural falls, and Dworshak and Hells Canyon Dams...
Code of Federal Regulations, 2014 CFR
2014-10-01
... salmon, Snake River fall chinook salmon, and Snake River spring/summer chinook salmon. 226.205 Section... Snake River sockeye salmon, Snake River fall chinook salmon, and Snake River spring/summer chinook... River salmon (except reaches above impassable natural falls, and Dworshak and Hells Canyon Dams...
Code of Federal Regulations, 2012 CFR
2012-07-01
... 33 Navigation and Navigable Waters 3 2012-07-01 2012-07-01 false Red Lake River, Minn.; logging regulations for portion of river above Thief River Falls. 207.380 Section 207.380 Navigation and Navigable... Red Lake River, Minn.; logging regulations for portion of river above Thief River Falls. (a) Parties...
Code of Federal Regulations, 2010 CFR
2010-07-01
... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Red Lake River, Minn.; logging regulations for portion of river above Thief River Falls. 207.380 Section 207.380 Navigation and Navigable... Red Lake River, Minn.; logging regulations for portion of river above Thief River Falls. (a) Parties...
Code of Federal Regulations, 2011 CFR
2011-07-01
... 33 Navigation and Navigable Waters 3 2011-07-01 2011-07-01 false Red Lake River, Minn.; logging regulations for portion of river above Thief River Falls. 207.380 Section 207.380 Navigation and Navigable... Red Lake River, Minn.; logging regulations for portion of river above Thief River Falls. (a) Parties...
Code of Federal Regulations, 2013 CFR
2013-07-01
... 33 Navigation and Navigable Waters 3 2013-07-01 2013-07-01 false Red Lake River, Minn.; logging regulations for portion of river above Thief River Falls. 207.380 Section 207.380 Navigation and Navigable... Red Lake River, Minn.; logging regulations for portion of river above Thief River Falls. (a) Parties...
Code of Federal Regulations, 2014 CFR
2014-07-01
... 33 Navigation and Navigable Waters 3 2014-07-01 2014-07-01 false Red Lake River, Minn.; logging regulations for portion of river above Thief River Falls. 207.380 Section 207.380 Navigation and Navigable... Red Lake River, Minn.; logging regulations for portion of river above Thief River Falls. (a) Parties...
3. ENVIRONMENT, FROM SOUTH, SHOWING RIVER ROAD RIDGE CARRYING CASSELMAN ...
3. ENVIRONMENT, FROM SOUTH, SHOWING RIVER ROAD RIDGE CARRYING CASSELMAN RIVER ROAD OVER CASSELMAN RIVER - River Road Bridge, Crossing Casselman River on Casselman River Road, Grantsville, Garrett County, MD
[Variation characteristics of runoff coefficient of Taizi River basin in 1967-2006].
Deng, Jun-Li; Zhang, Yong-Fang; Wang, An-Zhi; Guan, De-Xin; Jin, Chang-Jie; Wu, Jia-Bing
2011-06-01
Based on the daily precipitation and runoff data of six main embranchments (Haicheng River, Nansha River, Beisha River, Lanhe River, Xihe River, and Taizi River south embranchment) of Taizi River basin in 1967-2006, this paper analyzed the variation trend of runoff coefficient of the embranchments as well as the relationship between this variation trend and precipitation. In 1967-2006, the Taizi River south embranchment located in alpine hilly area had the largest mean annual runoff coefficient, while the Haicheng River located in plain area had the relatively small one. The annual runoff coefficient of the embranchments except Nansha River showed a decreasing trend, being more apparent for Taizi River south embranchment and Lanhe River. All the embranchments except Xihe River had an obvious abrupt change in the annual runoff coefficient, and the beginning year of the abrupt change differed with embranchment. Annual precipitation had significant effects on the annual runoff coefficient.
River habitat assessment for ecological restoration of Wei River Basin, China.
Yang, Tao; Wang, Shuo; Li, Xiaoping; Wu, Ting; Li, Li; Chen, Jia
2018-04-11
As an important composition component of river ecosystems, river habitats must undergo quality assessment to potentially provide scientific basis for river ecological restoration. Substrate composition, habitat complexity, bank erosion degree, river meandering degree, human activity intensity, vegetation buffer width, water quality, and water condition were determined as indicators for river habitat assessment. The comprehensive habitat quality index (CHQI) was established for the Wei River Basin. In addition, the indicator values were determined on the basis of a field investigation at 12 national hydrological stations distributed across the Wei, Jing, and Beiluo Rivers. The analytic hierarchy process was used to determine the indicator weights and thus distinguish the relative importance of the assessment indicator system. Results indicated that the average CHQIs for the Wei, Jing, and Beiluo Rivers were 0.417, 0.508, and 0.304, respectively. The river habitat quality for the three rivers was well. As for the whole river basin, the river habitat quality for 25% of the cross section was very well, the other 25% was well, and the 50% remaining was in critical state. The river habitat quality of the Jing River was better than that of the Wei and Beiluo Rivers.
Code of Federal Regulations, 2010 CFR
2010-10-01
... salmon, Snake River fall chinook salmon, and Snake River spring/summer chinook salmon. 226.205 Section... Snake River sockeye salmon, Snake River fall chinook salmon, and Snake River spring/summer chinook salmon. The following areas consisting of the water, waterway bottom, and adjacent riparian zone of...
The economic value of Trinity River water
Douglas, A.J.; Taylor, J.G.
1999-01-01
The Trinity River, largest tributary of the Klamath River, has its head-waters in the Trinity Alps of north-central California. After the construction of Trinity Dam in 1963, 90% of the Trinity River flow at Lewiston was moved to the Sacramento River via the Clear Creek Tunnel, a manmade conduit. Hydropower is produced at four installations along the route of Trinity River water that is diverted to the Sacramento River, and power production at three of these installations would diminish if no Trinity River water were diverted to the Sacramento River. After Trinity River water reaches the Sacramento River, it flows toward the Sacramento-San Joaquin Delta and San Francisco Bay. Trinity River water is pumped via Bureau of Reclamation canals and pumps to the northern San Joaquin Valley, where it is used for irrigated agriculture. The social cost of putting more water down the Trinity River is the sum of the value of the foregone consumer surplus from hydropower production as well as the value of the foregone irrigation water. Sharply diminished instream flows have also severely affected the size and robustness of Trinity River salmon, steelhead, shad and sturgeon runs. Survey data were used to estimate the non-market benefits of augmenting Trinity River instream flows by letting more water flow down the Trinity and moving less water to the Sacramento River. Preservation benefits for Trinity River instream flows and fish runs are $803 million per annum for the scenario that returns the most water down the Trinity River, a value that greatly exceeds the social cost estimate.The Trinity River, largest tributary of the Klamath River, has its headwaters in the Trinity Alps of north-central California. After the construction of Trinity Dam in 1963, 90% of the Trinity River flow at Lewiston was moved to the Sacramento River via the Clear Creek Tunnel, a manmade conduit. Hydropower is produced at four installations along the route of Trinity River water that is diverted to the Sacramento River, and power production at three of these installations would diminish if no Trinity River water were diverted to the Sacramento River. After Trinity River water reaches the Sacramento River, it flows toward the Sacramento-San Joaquin Delta and San Francisco Bay. Trinity River water is pumped via Bureau of Reclamation canals and pumps to the northern San Joaquin Valley, where it is used for irrigated agriculture. The social cost of putting more water down the Trinity River is the sum of the value of the foregone consumer surplus from hydropower production as well as the value of the foregone irrigation water. Sharply diminished instream flows have also severely affected the size and robustness of Trinity River salmon, steelhead, shad and sturgeon runs. Survey data were used to estimate the non-market benefits of augmenting Trinity River instream flows by letting more water flow down the Trinity and moving less water to the Sacramento River. Preservation benefits for Trinity River instream flows and fish runs are $803 million per annum for the scenario that returns the most water down the Trinity River, a value that greatly exceeds the social cost estimate.
NASA Astrophysics Data System (ADS)
Yu, Matthew; Cartwright, Ian
2014-05-01
Defining the relationship between the river and its river bank is important in constraining baseflow to a river and enhancing our ability in protecting water resources and riparian ecology. Hydraulic heads, geochemistry and 3H were measured in river banks along the Ovens River, southeast Australia. The Ovens River is characterised by the transition from a single channel river residing within a mountain valley to a multi-channel meandering river on broad alluvial plains in the lower catchment. The 3H concentrations of most near-river groundwater (less than 10 m from river channel) and bank water (10 - 30 m from the river channel) in the valley range between 1.93 and 2.52 TU. They are similar to those of the river, which are between 2.37 and 2.24 TU. These groundwater also have a Na/Cl ratio of 2.7 - 4.7 and are close to the river Na/Cl ratios. These similarities suggest that most river banks in the valley are recharged by the river. The hydraulic heads and EC values indicate that some of these river banks are recharged throughout the year, while others are only recharged during high flow events. Some near-river groundwater and bank water in the valley have a much lower 3H concentration, ranging from 0.97 to 1.27 TU. They also have a lower Na/Cl ratio of 1.6 - 3.1. These differences imply that some of the river banks in the valley are rarely recharged by the river. The lack of infiltration is supported by the constant head gradient toward the river and the constant EC values in these river banks. The river banks with bank infiltration are located in the first few hundred kilometres in the valley and in the middle catchment where the valley is broaden. In the first few hundred kilometres in the valley, it has a relatively flat landscape and does not allow a high regional water table to form. The river thus is always above the water table and recharges the river banks and the valley aquifers. In the broader valley, the relatively low lateral hydraulic gradient is sometimes reversed during high flow events, causing river to infiltrate the river banks. The river banks with no infiltration are in a location where the river runs in the middle of valley with a relatively steep incised bank. Thus, a strong lateral heads gradient toward the river can from in the bank, preventing river water from infiltration, even during a high flow event.
4. ENVIRONMENT, FROM NORTH, SHOWING RIVER ROAD BRIDGE CARRYING CASSELMAN ...
4. ENVIRONMENT, FROM NORTH, SHOWING RIVER ROAD BRIDGE CARRYING CASSELMAN RIVER ROAD OVER CASSELMAN RIVER, WITH MARYLAND GEOLOGICAL SURVEY STREAM-GAUGING STATION AT NORTHEAST CORNER OF BRIDGE - River Road Bridge, Crossing Casselman River on Casselman River Road, Grantsville, Garrett County, MD
Evaluating the effects of monthly river flow trends on Environmental Flow allocation
NASA Astrophysics Data System (ADS)
Torabi Haghighi, Ali; Klove, Bjorn
2010-05-01
The Natural river flow regime can be changed by the construction of hydraulic structures such as dams, hydropower plants, pump stations and so on. Due to the new river flow regime, some parts of water resources must be allocated to environmental flow (EF). There are more than 62 hydrological methods which have been proposed for calculating EF, although these methods don't have enough acceptability to be used in practical cases and The so other methods are preferred such as holistic,….. Most hydrological methods do not take basin physiography, climate, location of hydraulic structures, monthly river flow regime, historical trend of river (annually regime), purpose of hydraulic structures and so on, into consideration. In the present work, data from more than 180 rivers from Asia (71 rivers and 16 countries), Europe (79 Rivers and 23 countries), Americas (23 rivers and 10 countries) and Africa (12 rivers and 6 countries) were used to assess EF. The rivers were divided into 5 main groups of regular permanent rivers, semi regular permanent rivers, irregular permanent rivers, seasonal rivers and dry rivers, for each groups EF calculated by some hydrological methods and compared with the natural flow regime. The results showed that besides the amount of EF, the monthly distribution of flow is very important and should be considered in reservoir operation. In seasonal rivers and dry rivers, hydraulic structure construction can be useful for conserving aquatic ecosystems
River water pollution condition in upper part of Brantas River and Bengawan Solo River
NASA Astrophysics Data System (ADS)
Roosmini, D.; Septiono, M. A.; Putri, N. E.; Shabrina, H. M.; Salami, I. R. S.; Ariesyady, H. D.
2018-01-01
Wastewater and solid waste from both domestic and industry have been known to give burden on river water quality. Most of river water quality problem in Indonesia has start in the upper part of river due to anthropogenic activities, due to inappropriate land use management including the poor wastewater infrastructure. Base on Upper Citarum River Water pollution problem, it is interesting to study the other main river in Java Island. Bengawan Solo River and Brantas River were chosen as the sample in this study. Parameters assessed in this study are as follows: TSS, TDS, pH, DO, and hexavalent chromium. The status of river water quality are assess using STORET method. Based on (five) parameters, STORET value showed that in Brantas River, Pagerluyung monitoring point had the worst quality relatively compared to other monitoring point in Brantas River with exceeding copper, lead and tin compared to the stream standard in East Java Provincial Regulation No. 2 in 2008. Brantas River was categorized as lightly polluted river based on monitoring period 2011-2015 in 5 monitoring points, namely Pendem, Sengguruh, Kademangan, Meritjan and Kertosono.
Occurrence and effects of endocrine-disrupting chemicals in the St. Croix River
Elliott, Sarah M.; Lee, Kathy E.
2016-01-01
The St. Croix River is one of the last undisturbed, large floodplain rivers in the upper Mississippi River System. The Saint Croix National Scenic Riverway encompasses 255 river miles from the St. Croix Flowage and Namekagon River to the confluence of the St. Croix River with the Mississippi River at Prescott, Wisconsin. The Wild and Scenic Rivers Act of 1968 includes protection of the “outstandingly remarkable values” of the St. Croix and Namekagon rivers, which are included in the first eight designated wild and scenic rivers. The National Park Service (NPS) supports efforts to ensure these high-quality waters are not degraded by endocrine-disrupting or pharmaceutically active chemicals.
Initial river test of a monostatic RiverSonde streamflow measurement system
Teague, C.C.; Barrick, D.E.; Lilleboe, P.M.; Cheng, R.T.; ,
2003-01-01
A field experiment was conducted on May 7-8, 2002 using a CODAR RiverSonde UHF radar system at Vernalis, California on the San Joaquin River. The monostatic radar configuration on one bank of the river, with the antennas looking both upriver and downriver, provided very high-quality data. Estimates of both along-river and cross-river surface current were generated using several models, including one based on normal-mode analysis. Along-river surface velocities ranged from about 0.6 m/s at the river banks to about 1.0 m/s near the middle of the river. Average cross-river surface velocities were 0.02 m/s or less.
Federal Register 2010, 2011, 2012, 2013, 2014
2012-05-23
... DEPARTMENT OF TRANSPORTATION Surface Transportation Board [Docket No. FD 35622] SteelRiver Infrastructure Partners LP, SteelRiver Infrastructure Associates LLC, SteelRiver Infrastructure Fund North America LP, and Patriot Funding LLC--Control Exemption--Patriot Rail Corp., et al. SteelRiver...
Assessment of Long-Term Changes in River Stage of the Lowermost Mississippi River
NASA Astrophysics Data System (ADS)
Joshi, S.; Xu, Y. J.
2016-02-01
Long-term changes in river stage can reflect dynamics of river beds. Such changes in the lower reach of a river entering the sea can also indicate sea level rise and land subsidence. The lowermost Mississippi River has experienced changes in its stages over the past several decades which, however, have not been studied yet. Comprehensive analysis of long-term changes in stages of this river can aid in understanding its route downstream and differentiate between sediment erosion and deposition mechanics at several of its sites. In this study, we utilize long-term records on river stages along a 320-km reach of the lowermost Mississippi River from the Old River Control Structure to New Orleans in order to assess the channel dynamics of the highly engineered river. Eight locations along the reach are selected, including Red River Landing, Bayou Sara, St. Francisville, Baton Rouge, Dolandsonville, College Point, Bonnet Carre, and Carrolton. River stages at the locations are analyzed under the low-, medium-, and high-flow conditions over the past three decades. Changes in slope of the river stages between these locations are determined based on difference in their river stages and length of their reach. Preliminary results from this study show that the river stages drop systematically as the river moves downstream. The drop is very low from Red River Landing to Baton Rouge; it suddenly increases from Baton Rouge to the next site at Bonnet Carre, then decreases for the next few sites up to Carrolton. We also found that some river reaches experienced deposition while other river reaches had erosion during the past decades. This paper will present major findings in long term changes in lowermost Mississippi river stages and their slopes. It will also discuss implications of these findings for sediment accumulation and possible river diversion locations.
76 FR 13572 - Proposed Flood Elevation Determinations
Federal Register 2010, 2011, 2012, 2013, 2014
2011-03-14
.... Specifically, it addresses the following flooding sources: Left Bank Overflow Main Stem Skagit River, Left Bank Overflow Main Stem Skagit River/South Fork Skagit River, Left Bank Overflow North Fork Skagit River, Main Stem Skagit River, North Fork Skagit River, Overflow from the Main Stem Skagit River between the North...
Moring, J. Bruce
2012-01-01
The total number of fish species collected was the same in the Devils River and Pecos River, but the species found in the two rivers varied slightly. The number of fish species generally increased from the site farthest upstream to the site farthest downstream in the Devils River, and decreased between the site farthest upstream and site farthest downstream in the Pecos River. The redbreast sunfish was the most abundant species collected in the Devils River, and the blacktail shiner was the most abundant species collected in the Pecos River. Comparing the species from each river, the percentage of omnivorous fish species was larger at the more downstream sites closer to Amistad Reservoir, and the percentage of species tolerant of environmental stressors was larger in the Pecos River. The fish community, assessed on the basis of the number of shared species among the sites sampled, was more similar to the fish community at the other sites on the same river than it was to the fish community from any other site in the other river. More macroinvertebrate taxa were collected in the Devils River than in the Pecos River. The largest number of macroinvertebrate taxa were from the site second farthest downstream on the Devils River, and the smallest numbers of macroinvertebrate taxa were from the farthest downstream site on the Pecos River. Mayflies were more common in the Devils River, and caddisflies were less common than mayflies at most sites. Net-spinning caddisflies were more common at the Devils River sites. The combined percent of mayfly, caddisfly, and stonefly taxa was generally larger at the Pecos River sites. Riffle beetles were the most commonly collected beetle taxon among all sites, and water-penny beetles were only collected at the Pecos River sites. A greater number of true midge taxa were collected more than any other taxa at the genus and species taxonomic level. Non-insect macroinvertebrate taxa were more common at the Devils River sites. Corbicula sp. (presumably the introduced Asian clam) was found at sites in both rivers, and amphipods were more abundant in the Devils River. The Margalef species richness index, based on aquatic insect taxa only, was larger at the Devils River sites than at the Pecos River sites. The Hilsenhoff's biotic index was largest at the site farthest downstream in the Devils River and smallest at the site second farthest downstream in the Pecos River. Overall similarity among sites based on the number of shared macroinvertebrate taxa indicated that each site is more similar to other sites on the same river than to sites on the other river.
Brabets, Timothy P.
2001-01-01
Flow data were collected from two adjacent rivers in Yukon?Charley Rivers National Preserve, Alaska?the Nation River (during 1991?2000) and the Kandik River (1994?2000)?and from the Yukon River (1950?2000) at Eagle, Alaska, upstream from the boundary of the preserve. These flow records indicate that most of the runoff from these rivers occurs from May through September and that the average monthly discharge during this period ranges from 1,172 to 2,210 cubic feet per second for the Nation River, from 1,203 to 2,633 cubic feet per second for the Kandik River, and from 112,000 to 224,000 cubic feet per second for the Yukon River. Water-quality data were collected for the Nation River and several of its tributaries from 1991 to 1992 and for the Yukon River at Eagle from 1950 to 1994. Three tributaries to the Nation River (Waterfall Creek, Cathedral Creek, and Hard Luck Creek) have relatively high concentrations of calcium, magnesium, and sulfate. These three watersheds are underlain predominantly by Paleozoic and Precambrian rocks. The Yukon River transports 33,000,000 tons of suspended sediment past Eagle each year. Reflecting the inputs from its major tributaries, the water of the Yukon River at Eagle is dominated by calcium?magnesium bicarbonate.
Aerial view of the entire bridge crossing the Tennessee River ...
Aerial view of the entire bridge crossing the Tennessee River looking up river. The swing bridge, when open, permits river navigational traffic to ply the river. Construction of a replacement bridge, to be located 93.27 feet down river, has now started. - Bridgeport Swing Span Bridge, Spanning Tennessee River, Bridgeport, Jackson County, AL
A new framework for assessing river ecosystem health with consideration of human service demand.
Luo, Zengliang; Zuo, Qiting; Shao, Quanxi
2018-06-01
In order to study river health status from harmonic relationship between human and natural environment, a river health evaluation method was proposed from the aspects of ecosystem integrity and human service demand, and the understanding of river health connotation. The proposed method is based on the harmony theory and two types of river health assessment methods (the forecasting model and index evaluation). A new framework for assessing river water health was then formed from the perspective of harmony and dynamic evolution between human service demand and river ecosystem integrity. As a case study, the method and framework were applied to the Shaying River Basin, a tributary of the most polluted Huaihe River Basin in China. The health status of the river's ecosystem and its effect on the mainstream of Huaihe River were evaluated based on water ecological experiment. The results indicated that: (1) the water ecological environment in Shaying River was generally poor and showed a gradual changing pattern along the river. The river health levels were generally "medium" in the upstream but mostly "sub-disease" in the midstream and downstream, indicating that the water pollution in Shaying River were mainly concentrated in the midstream and downstream; (2) the water pollution of Shaying River had great influence on the ecosystem of Huaihe River, and the main influencing factors were TN, followed by TP and COD Mn ; (3) the natural attribute of river was transferring toward to the direction of socialization due to the increasing human activities. The stronger the human activity intervention is, the faster the transfer will be and the more river's attributes will match with human service demand. The proposed framework contributes to the research in water ecology and environment management, and the research results can serve as an important reference for basin management in Shaying River and Huaihe River. Copyright © 2018. Published by Elsevier B.V.
Characteristics of water quality of rivers related to land-use in Penang Island Malaysia
NASA Astrophysics Data System (ADS)
Yen, Lim Jia; Matsumoto, Yoshitaka; Yin, Chee Su; Wern, Hong Chern; Inoue, Takanobu; Usami, Akiko; Iwatsuki, Eiji; Yagi, Akihiko
2017-10-01
A study of the Water Quality Index (WQI) of rivers in Penang Island, Malaysia conducted by Universiti Sains Malaysia from October 2012 to January 2013 shows that almost all rivers in Penang Island were slightly polluted or polluted. However, WQI does not clarify each water quality indices, for example nutrients and organic pollutants, that reflect the land-use and pollution source in the catchment. Therefore, in this research, the main objectives are to investigate the interaction of land-use and the water quality of rivers in Penang Island, the quantity of pollutant loads discharged, and identification of the pollution sources along the rivers. The procedure starts from the selection of rivers and parameters for investigation, carrying out field survey and sampling, measuring and analyzing each sample, and lastly, providing a conclusion. The three rivers selected are Pinang River, Keluang River and Burung River. In this research, the results show that total organic carbon (TOC) increases generally as the rivers flow towards the river mouths, which means the degree of organic pollution increases along the rivers. In Pinang River, TOC increases as the tributaries from housing areas flow into the mainstream whereas in Keluang River, a marked increase of TOC is shown in the location where the wastewater from a sewage treatment plant discharges. In Burung River, TOC increases as the river flows through the paddy fields. In the principal component analysis, all sampling points of the three rivers are able to be classified into five groups based on the characteristics of water quality. For example, upstream of Keluang River and Burung River show mutual characteristics in terms of man-made pollution index and heavy metal pollution index. As a conclusion, the results in this research show that the characteristics of water quality in Penang Island are highly affected by land-use surrounding the rivers.
GENERAL VIEW OF SOUTH SAN GABRIEL RIVER BRIDGE, RIVER SPAN, ...
GENERAL VIEW OF SOUTH SAN GABRIEL RIVER BRIDGE, RIVER SPAN, LOOKING NORTHWEST. - South San Gabriel River Bridge, Spanning South Fork of San Gabriel River at Georgetown at Business Route 35, Georgetown, Williamson County, TX
O'Donnell, T. K.; Galat, D.L.
2007-01-01
The Upper Mississippi River is characterized by a series of locks and dams, shallow impoundments, and thousands of river channelization structures that facilitate commercial navigation between Minneapolis, Minnesota, and Cairo, Illinois. Agriculture and urban development over the past 200 years have degraded water quality and increased the rate of sediment and nutrient delivery to surface waters. River enhancement has become an important management tool employed to address causes and effects of surface water degradation and river modification in the Upper Mississippi River Basin. We report information on individual river enhancement projects and contrast project densities, goals, activities, monitoring, and cost between commercially non-navigated and navigated rivers (Non-navigated and Navigated Rivers, respectively). The total number of river enhancement projects collected during this effort was 62,108. Cost of all projects reporting spending between 1972 and 2006 was about US$1.6 billion. Water quality management was the most cited project goal within the basin. Other important goals in Navigated Rivers included in-stream habitat improvement and flow modification. Most projects collected for Non-navigated Rivers and their watersheds originated from the U.S. Department of Agriculture (USDA). The U.S. Army Corps of Engineers and the USDA were important sources for projects in Navigated Rivers. Collaborative efforts between agencies that implement projects in Non-navigated and Navigated Rivers may be needed to more effectively address river impairment. However, the current state of data sources tracking river enhancement projects deters efficient and broad-scale integration. ?? Journal compilation ?? 2007 Society for Ecological Restoration International.
Federal Register 2010, 2011, 2012, 2013, 2014
2012-04-18
...-AA08 Special Local Regulations; Lowcountry Splash Open Water Swim, Wando River and Cooper River, Mount... at Patriots Point on the Cooper River. Approximately 600 swimmers will be participating in the swim... Special Local Regulations; Lowcountry Splash Open Water Swim, Wando River and Cooper River, Mount Pleasant...
1987-11-01
Des P/o,,nes River Grant Cut -off V 1Kankrokee Cut- off Drsdn slndCountyI Line Bordwell Isi. V _ KankakeKRiver 2 */0 7r Prairle Cr 6 0 1 M1 Survey date...2 x 10 6t 81 279 River 279 13 February 1986 275 Kankak Des P/amnes RIver Gran7 Cree Cut-off DrsenIladCount y Line Bordwell Isr. 0 1 M1 ’kornkokee A...Gat Cut - off KankakeeFiver ’e Drsdn slndCounty Line Bordwell s 1 mi 2urve date FerarM1,i Kankakee River :2.4 oCr. X9Kankakcee River :14 ML 0- 5
Lucchitta, Ivo; Holm, Richard F.; Lucchitta, Baerbel K.
2013-01-01
The southwesterly course of the probably pre–early Miocene and possibly Oligocene Crooked Ridge River can be traced continuously for 48 km and discontinuously for 91 km in northern Arizona (United States). The course is visible today in inverted relief. Pebbles in the river gravel came from at least as far northeast as the San Juan Mountains (Colorado). The river valley was carved out of easily eroded Jurassic and Cretaceous rocks whose debris overloaded the river with abundant detritus, probably steepening the gradient. After the river became inactive, the regional drainage network was rearranged three times, and the nearby Four Corners region was lowered 1–2 km by erosion. The river provides constraints on the early evolution of the Colorado River and Grand Canyon. Continuation of this river into lakes in Arizona or Utah is unlikely, as is integration through Grand Canyon by lake spillover. The downstream course of the river probably was across the Kaibab arch in a valley roughly coincident with the present eastern Grand Canyon. Beyond this point, the course may have continued to the drainage basin of the Sacramento River, or to the proto–Snake River drainage. Crooked Ridge River was beheaded by the developing San Juan River, which pirated its waters and probably was tributary to a proto–Colorado River, flowing roughly along its present course west of the Monument upwarp.
Human impacts on fluvial systems - A small-catchment case study
NASA Astrophysics Data System (ADS)
Pöppl, Ronald E.; Glade, Thomas; Keiler, Margreth
2010-05-01
Regulations of nearly two-thirds of the rivers worldwide have considerable influences on fluvial systems. In Austria, nearly any river (or) catchment is affected by humans, e.g. due to changing land-use conditions and river engineering structures. Recent studies of human impacts on rivers show that morphologic channel changes play a major role regarding channelization and leveeing, land-use conversions, dams, mining, urbanization and alterations of natural habitats (ecomorphology). Thus 'natural (fluvial) systems' are scarce and humans are almost always inseparably interwoven with them playing a major role in altering them coincidentally. The main objective of this study is to identify human effects (i.e. different land use conditions and river engineering structures) on river bed sediment composition and to delineate its possible implications for limnic habitats. The study area watersheds of the 'Fugnitz' River (~ 140km²) and the 'Kaja' River (~ 20km²) are located in the Eastern part of the Bohemian Massif in Austria (Europe) and drain into the 'Thaya' River which is the border river to the Czech Republic in the north of Lower Austria. Furthermore the 'Thaya' River is eponymous for the local National Park 'Nationalpark Thayatal'. In order to survey river bed sediment composition and river engineering structures facies mapping techniques, i.e. river bed surface mapping and ecomorphological mapping have been applied. Additionally aerial photograph and airborne laserscan interpretation has been used to create land use maps. These maps have been integrated to a numerical DEM-based spatial model in order to get an impression of the variability of sediment input rates to the river system. It is hypothesized that this variability is primarily caused by different land use conditions. Finally river bed sites affected by river engineering structures have been probed and grain size distributions have been analyzed. With these data sedimentological and ecological/ecomorphological effects of various river engineering structures (i.e. dams, weirs, river bank- and river bed protection works) on river bed sediment composition and on limnic habitats are evaluated. First results reveal that 'land use' is a dominant factor concerning river bed sediment composition and limnic habitat conditions. Further outcomes will be presented on European Geosciences Union General Assembly, 2010.
Barrett, Dominic A.; Leslie, David M.
2012-01-01
Examination of age structures and sex ratios is useful in the management of northern river otters (Lontra canadensis) and other furbearers. Reintroductions and subsequent recolonizations of river otters have been well documented, but changes in demographics between expanding and established populations have not been observed. As a result of reintroduction efforts, immigration from Arkansas and northeastern Texas, and other efforts, river otters have become partially reestablished throughout eastern and central Oklahoma. Our objective was to examine age structures of river otters in Oklahoma and identify trends that relate to space (watersheds, county) and time (USDA Animal and Plant Health Inspection Service county trapping records). We predicted that river otters in western areas of the state were younger than river otters occurring farther east. From 2005–2007, we obtained salvaged river otter carcasses from federal and state agencies, and we live-captured other river otters using leg hold traps. Seventy-two river otters were sampled. Overall, sex ratios were skewed toward females (1F∶0.8M), but they did not differ among spatiotemporal scales examined. Teeth were removed from salvaged and live-captured river otters (n = 63) for aging. One-year old river otters represented the largest age class (30.2%). Proportion of juveniles (<1 y old) in Oklahoma (19.0%) was less than other states. Mean age of river otters decreased from east-to-west in the Arkansas River and its tributaries. Mean age of river otters differed between the Canadian River Watershed (0.8 y) and the Arkansas River Watershed (2.9 y) and the Canadian River Watershed and the Red River Watershed (2.4 y). Proportion of juveniles did not differ among spatiotemporal scales examined. Similar to age structure variations in other mammalian carnivores, colonizing or growing western populations of river otters in Oklahoma contained younger ages than more established eastern populations.
2003-01-01
Sockeye salmon ( Oncorhynchus nerka ) Snake River Endangered Stream Yearling + 11/2/91 Steelhead trout ( Oncorhynchus mykiss) Snake River... Oncorhynchus tshawytscha) Snake River spring/summer Threatened Stream Yearling + 4/22/92 Snake River fall Threatened Ocean Subyearling 4...Willamette River Threatened Ocean Subyearling + 3/24/99 Chum salmon ( Oncorhynchus keta) Columbia River Threatened Ocean Subyearling 3/25/99
The Wabash River is a tributary of the Ohio River. This river system consists of headwaters and small streams, medium river reaches in the upper Wabash watershed, and large river reaches in the lower Wabash watershed. A large part of the river system is situated in agricultural a...
Water quality of arctic rivers in Finnish Lapland.
Niemi, Jorma
2010-02-01
The water quality monitoring data of eight rivers situated in the Finnish Lapland above the Arctic Circle were investigated. These rivers are icebound annually for about 200 days. They belong to the International River Basin District founded according to the European Union Water Framework Directive and shared with Norway. They are part of the European river monitoring network that includes some 3,400 river sites. The water quality monitoring datasets available varied between the rivers, the longest comprising the period 1975-2003 and the shortest 1989-2003. For each river, annual medians of eight water quality variables were calculated. In addition, medians and fifth and 95th percentiles were calculated for the whole observation periods. The medians indicated good river water quality in comparison to other national or foreign rivers. However, the river water quality oscillated widely. Some rivers were in practice in pristine state, whereas some showed slight human impacts, e.g., occasional high values of hygienic indicator bacteria.
Naomi Cohn
1998-01-01
What's been done on Chicago Area Rivers is truly an inspiration. People's ability to improve these rivers shows what can be improved anywhere, even in a highly developed and complex urban setting like Chicago. A veteran staffer with the Friends of the Chicago River recently concluded: "People look at what's being accomplished on the Chicago River...
NASA Astrophysics Data System (ADS)
Yang, S. Y.; Jan, C. D.; Wang, Y. C.
2014-12-01
Active evolving rivers are some of the most dynamic and sensitive parts of landscapes. From geologic and geomorphic perspectives, a stable river channel can adjust its width, depth, and slope to prevent significant aggradation or degradation caused by external triggers, e.g., hydrologic events caused by typhoon storms. In particular, the processes of lateral riverbank erosion play a majorly important role in forming horizontal river geomorphology, dominating incised river widens and meanders. Sediment materials produced and mobilized from riverbanks can also be substantial sediment supplying into river channel networks, affecting watershed sediment yield. In Taiwan, the geological and climatic regimes usually combine to generate severely lateral erosion and/or riverbed deposition along river channels, causing the significant change in river width. In the August of 2009, Typhoon Morakot brought severe rainfall of about 2000 mmin Southern Taiwan during three days at the beginning of Aug. 5, leading to significant changes in geomorphic system. Here we characterized river width widening (including Cishan, Laonong, and Ilao Rivers) in the Kaoping River watershed after Typhoon Morakot disturbance interpreted through a power law. On the basis of a temporal pair (2008 and 2009) of Formosat-II (Formosa satellite II) images analysis, the river channels were digitalized within geographic information system (GIS), and river widths were extracted per 100 m along the rivers, then differentiating the adjustment of river width before and after Typhoon Morkot. The river width adjusted from -83 m (contracting) to 1985 m (widening), with an average of 170 m. The noncumulative frequency-magnitude distribution for river width adjustment caused by Typhoon Morakot in the study area satisfies a power-law relation with a determined coefficient (r2) of 0.95, over the range from 65 m to 2373m in the study area. Moreover, the value of the power-law exponent is equal to -2.09. This pattern suggests that river channel widening caused by large, infrequent hydrologic episodes has self-organized criticality. This study can provide useful information to river and watershed management, thereby refining the prevention and mitigation of hazard risks due to the effect of river width widening.
NASA Astrophysics Data System (ADS)
Wang, Juan; Wang, Yue; Yang, Haizhen; Lu, Zhibo; Xu, Xiaotian
2010-11-01
The River Bailianjing is an iconic landscape feature known to all residents in Pudong area and running through the Shanghai Expo 2010 Park. The river and its basin was a complex living ecosystem which supports a unique variety of flora and fauna several decades ago. However, as a result of unsuccessful pollution source control, sewage and first flow of the storm water is directly coming into the river in some catchment. The water quality of the river is seriously organically polluted now. The typical organic pollutants are COD, NH3-N, TN and TP, which cause the extinction of the water plants and aquatic. Furthermore, the artificial hard river banks isolate the river course and the land, which damaged the whole ecological system totally. The nature of the River Bailianjing and its history has resulted in many government departments and authorities and non government organizations having jurisdiction and/or an interest in the river's management. As a new tool to improve river management, the river health assessment has become the major focus of ecological and environmental science. Consequently, research on river health evaluation and its development on river management are of great theoretical and practical significance. In order to evaluate the healthy status of the River Bailianjing and prepare comprehensive scientific background data for the integrated river ecological rehabilitation planning, the health evaluation indicator system for River Bailianjing is brought forward. The indicator system has three levels: the first is target layer; the second is criteria layer, including five fields: water quality characteristics, hydrology characteristics, river morphology, biological characteristics and river scenic beauty; the third is an index layer, a total of 15 specific indicators included. Fuzzy AHP method is used to evaluate the target river's health status, and five grades are set up to describe it: healthy, sub health, marginal, unhealthy and pathological. The methodology and experience of the urban river health evaluation illustrated in the paper can be good case study materials for other cities with the similar situation.
NASA Astrophysics Data System (ADS)
Bandyopadhyay, Shreya; Saha, Sushmita; Ghosh, Kapil; Kumar De, Sunil
2013-07-01
The main objective of the paper is to find the probable causes behind the shifting course of the Haora River, one of the major rivers of West Tripura and detachment of one of its major tributaries, the Katakhal River. From a recent satellite image, we observed that the River Haora has changed its course drastically near the confluence. Earlier, it used to take a sharp northward bend to meet with the River Titas immediately after crossing the Indo-Bangladesh border; but presently it is flowing westward to do so. Moreover, the Katakhal River, a right bank tributary of the River Haora, that used to flow through the northern side of the city of Agartala and meet with the River Haora at Bangladesh, is no longer a tributary of the Haora River. Now it is completely detached from the Haora River and meets with the River Titas separately. Spatiotemporal maps have been used to detect the changes. Field investigation, with the help of GPS, has been done in order to find the link between the Haora River and the Katakhal River within the Indian territory. Changing patterns of the Haora and Katakhal River confluences are also analysed, and earlier courses are identified. The shifting trends of both of these two rivers are found along the flanks of the interfluvial area because of microscale tectonic activity, i.e., upliftment of the interfluvial zone.
Setting Preferences of High and Low Use River Recreationists: How Different are They?
NASA Astrophysics Data System (ADS)
Kainzinger, Silvia; Arnberger, Arne; Burns, Robert C.
2016-11-01
Whitewater boaters often choose a river based on their preferences for attributes important for their trip experience. This study explored whether preferences and tradeoffs of whitewater boaters for social, resource, and managerial attributes of riverscapes differ among a high and a low use river in the United States by employing a stated choice approach. River trip scenarios were displayed using verbal descriptions and computer-generated photographs. Results indicate that use levels were more important for boaters on the low use river, whereas river difficulty and river access fee was of higher importance for the high use river boaters, who are more involved in this whitewater activity. Preferences for waiting times and trip length did not differ between the samples. Findings suggest that whitewater boaters of high and low use rivers have a different tradeoff behavior among river setting attributes, which has implications for river recreation management.
Qing, Xu-yao; Ren, Yu-fen; Lü, Zhi-qiang; Wang, Xiao-ke; Pang, Rong; Deng, Rui; Meng, Ling; Ma, Hui-ya
2015-07-01
To understand the secondary river quality in Chongqing urban area, six typical secondary rivers were chosen to investigate the pollution characteristics of total nitrogen and total phosphorus and to evaluate the water eutrophication level according to the monitoring data of water physicochemical characteristics and chlorophyll content from April 2013 to March 2014. The study results showed that: the six rivers mentioned above have been seriously polluted by TN and TP, with the monthly mean values of TN and TP far exceeding the universally accepted threshold values of water eutrophication. Water eutrophicaton appraisal result indicated that all rivers in each season were in a state of eutrophication, and the eutrophication level could be arranged in the order of Panxi River > Qingshui River > Tiaodeng River > Huaxi River > Funiu River > Chaoyang River. The seasonal changes in TN and TP of secondary rivers were significant, with high concentrations of TN and TP in spring and winter, and lower concentrations in summer and autumn. TN and TP of the rivers showed a trend of increasing from the upstream to the downstream in each season. Pollutant concentration accumulated gradually along rivers and the maximum accumulation rate reached 1. 25 mg . (L . km) -1. Therefore, further study on urban secondary river pollution characteristics is of great significance to urban water pollution control.
Liu, Dong; Pan, Delu; Bai, Yan; He, Xianqiang; Wang, Difeng; Zhang, Lin
2015-11-15
Real-time monitoring of riverine dissolved organic carbon (DOC) and the associated controlling factors is essential to coastal ocean management. This study was the first to simulate the monthly DOC concentrations at the Datong Hydrometric Station for the Changjiang River and at the Lijin Hydrometric Station for the Yellow River from 2000 to 2013 using a multilayer back-propagation neural network (MBPNN), along with basin remote-sensing products and river in situ data. The average absolute error between the modeled values and in situ values was 9.98% for the Changjiang River and 10.84% for the Yellow River. As an effect of water dilution, the variations of DOC concentrations in the two rivers were significantly negatively affected by discharge, with lower values reported during the wet season. Moreover, vegetation growth status and agricultural activities, represented by the gross primary product (GPP) and cropland area percent (CropPer) in the river basin, respectively, also significantly affected the DOC concentration in the Changjiang River, but not the Yellow River. The monthly riverine DOC flux was calculated using modeled DOC concentrations. In particular, the riverine DOC fluxes were affected by discharge, with 71.06% being reported for the Changjiang River and 90.71% for the Yellow River. Over the past decade, both DOC concentration and flux in the two rivers have not shown significant changes. Copyright © 2015 Elsevier Ltd. All rights reserved.
Zou, Junyu
2016-01-01
The carbon isotopic composition (δ13C) of dissolved and particulate inorganic carbon (DIC; PIC) was used to compare and analyze the origin, dynamics and evolution of inorganic carbon in two headwater tributaries of the Xi River, Southwest China. Carbonate dissolution and soil CO2 were regarded as the primary sources of DIC on the basis of δ13CDIC values which varied along the Nanpan and Beipan Rivers, from −13.9‰ to 8.1‰. Spatial trends in DIC differed between the two rivers (i.e., the tributaries), in part because factors controlling pCO2, which strongly affected carbonate dissolution, differed between the two river basins. Transport of soil CO2 and organic carbon through hydrologic conduits predominately controlled the levels of pCO2 in the Nanpan River. However, pCO2 along the upper reaches of the Nanpan River also was controlled by the extent of urbanization and industrialization relative to agriculture. DIC concentrations in the highly urbanized upper reaches of the Nanpan River were typical higher than in other carbonate-dominated areas of the upper Xi River. Within the Beipan River, the oxidation of organic carbon is the primary process that maintains pCO2 levels. The pCO2 within the Beipan River was more affected by sulfuric acid from coal industries, inputs from a scenic spot, and groundwater than along the Nanpan River. With regards to PIC, the contents and δ13C values in the Nanpan River were generally lower than those in the Beipan River, indicating that chemical and physical weathering contributes more marine carbonate detritus to the PIC along the Beipan River. The CO2 evasion flux from the Nanpan River was higher than that in the Beipan River, and generally higher than along the middle and lower reaches of the Xi River, demonstrating that the Nanpan River is an important net source of atmospheric CO2 in Southwest China. PMID:27513939
Macek-Rowland, Kathleen M.
2000-01-01
Annual suspended-sediment loads for water years 1954 through 1998 were estimated for the major tributaries in the Missouri River Basin between Garrison Dam and Lake Oahe in North Dakota and for the Missouri River at Garrison Dam and the Missouri River at Bismarck, N. Dak. The major tributaries are the Knife River, Turtle Creek, Painted Woods Creek, Square Butte Creek, Burnt Creek, Heart River, and Apple Creek. Sediment and streamflow data used to estimate the suspended-sediment loads were from selected U.S. Geological Survey streamflow-gaging stations located within each basin. Some of the stations had no sediment data available and limited continuous streamflow data for water years 1954 through 1998. Therefore, data from nearby streamflow-gaging stations were assumed for the calculations. The Heart River contributed the largest amount of suspended sediment to the Missouri River for 1954-98. Annual suspended-sediment loads in the Heart River near Mandan ranged from less than 1 to 40 percent of the annual suspended-sediment load in the Missouri River. The Knife River contributed the second largest amount of suspended sediment to the Missouri River. Annual suspended-sediment loads in the Knife River at Hazen ranged from less than 1 to 19 percent of the annual suspended-sediment load in the Missouri River. Apple Creek, Turtle Creek, Painted Woods Creek, Square Butte Creek, and Burnt Creek all contributed 2 percent or less of the annual suspended-sediment load in the Missouri River. The Knife River and the Heart River also had the largest average suspended-sediment yields for the seven tributaries. The yield for the Knife River was 91.1 tons per square mile, and the yield for the Heart River was 133 tons per square mile. The remaining five tributaries had yields of less than 24 tons per square mile based on total drainage area.
Angradi, Ted R.; Bolgriend, David W.; Jicha, Terri M.; Pearson, Mark S.; Taylor, Debra L.; Moffett, Mary F.; Blocksom, Karen A.; Walters, David M.; Elonen, Colleen M.; Anderson, Leroy E.; Lazorchak, James M.; Reavie, Euan D.; Kireta, Amy R.; Hill, Brian H.
2011-01-01
We assessed the North American mid-continent great rivers (Upper Mississippi, Missouri, and Ohio). We estimated the extent of each river in most- (MDC) or least-disturbed condition (LDC) based on multiple biological response indicators: fish and macroinvertebrate, trophic state based on chlorophyll a, macrophyte cover, and exposure of fish-eating wildlife to toxic contaminants in fish tissue (Hg, total chlordane, total DDT, PCBs). We estimated the extent of stressors on each river including nutrients, suspended solids, sediment toxicity, invasive species, and land use (agriculture and impervious surface). All three rivers had a greater percent of their river length in MDC than in LDC based on fish assemblages. The Upper Mississippi River had the greatest percent of river length with eutrophic status. The Ohio River had the greatest percent of river length with fish with tissue contaminant levels toxic to wildlife. Overall, condition indices based on fish assemblages were more sensitive to stress than macroinvertebrate indices. Compared to the streams in its basin, more of the Upper Mississippi and Missouri Rivers were in MDC for nutrients than the Ohio River. Invasive species (Asian carp and Dreissenid mussels) were less widespread and less abundant on the Missouri River than on the other great rivers. The Ohio River had the most urbanized floodplains (greatest percent impervious surface). The Missouri River had the most floodplain agriculture. The effect of large urban areas on river condition was apparent for several indicators. Ecosystem condition based in fish assemblages, trophic state, and fish tissue contamination was related to land use on the floodplain and at the subcatchment scale. This is the first unbiased bioassessment of the mid-continent great rivers in the United States. The indicators, condition thresholds, results, and recommendations from this program are a starting point for improved future great river assessments.
NASA Astrophysics Data System (ADS)
Paz-Alberto, Annie Melinda; Sison, Melissa Joy M.; Bulaong, Edmark Pablo; Pakaigue, Marietta A.
2016-06-01
Geophysical changes in river outlet, river upstream and coastlines near the rivers of Bucao and Santo Tomas in Zambales, Philippines were analyzed using the Google Earth's historical satellite imageries from 2004 to 2013. Data in 2015 were gathered from in situ field measurements ground validation. The study aimed to measure and determine changes in the width of river outlet, width of river bank upstream and shifting of coastline. Results revealed that there was a decrease and increase in the width size of the Bucao and Santo Tomas river outlets, respectively during the study period. Geophysical changes occurred in the two rivers due to the continuous supply of lahar as an after effect of the Mount Pinatubo eruption in 1991. Coastline positions near the two rivers also changed. The highest rate of erosion along the coastal area was prevalently observed near the river outlet of both rivers. Moreover, accretion was observed in the coastline of Santo Tomas and erosion phenomenon was observed in the North and South coastlines of Bucao River. The shifting was caused by natural processes such as erosion, sedimentation and natural calamities as well as anthropogenic processes such as reclamation/quarrying. Occurrence of erosion and sedimentation played active roles in the changes of coastlines during the study period. Furthermore, the upstream of the Bucao river changed physically due to deposits of lahar present in the upstream which are being discharged directly and continuously going down to the river. Generally, the width of the Bucao River upstream decreased its size because of the accumulated sediment in the riverbank. On the other hand, the observed erosion is caused by high velocity of river during heavy rains and typhoons. The width of the Santo Tomas river bank upstream did not change due to the construction of concrete dikes which prevent the lahar-filled river from breaching the embankment and flooding the agricultural, residential and commercial areas near the river.
Ebbert, James C.
2003-01-01
The U.S. Geological Survey, Washington State Department of Ecology, and Puyallup Tribe of Indians monitored water temperature, specific conductance, pH, and dissolved-oxygen concentrations in the White River at river miles 4.9 and 1.8 from August until mid-October 2002. Water diverted from the White River upstream from the monitoring sites into Lake Tapps is returned to the river at river mile 3.6 between the two sites. The same characteristics were measured in a cross section of the Puyallup River estuary at river mile 1.5 during high and low tides in September 2002. In late August, maximum daily water temperatures in the White River of 21.1°C (degrees Celsius) at river mile 4.9 and 19.6°C at river mile 1.8 exceeded the water-quality standard of 18°C at both monitoring sites. In mid-September, maximum daily water temperatures at river mile 4.9 exceeded the standard on 5 days. From August 2-25, water temperatures at both monitoring sites were similar and little or no water was discharged from Lake Tapps to the White River. Increases in water temperature at river mile 1.8 in late September and early October were caused by the mixing of warmer water discharged from Lake Tapps with cooler water in the White River.Specific conductance in the White River usually was lower at river mile 1.8 than at river mile 4.9 because of mixing with water from Lake Tapps, which has a lower specific conductance. Maximum values of pH in the White River at river mile 4.9 often exceeded the upper limit of the water-quality standard, 8.5 pH units, from early September until mid-October, when turbidity decreased. The pH standard was not exceeded at river mile 1.8. Dissolved-oxygen concentrations in the White River were often lower at river mile 1.8 than at river mile 4.9 because of mixing with water discharged from Lake Tapps, which has lower dissolved-oxygen concentrations. The lowest concentration of dissolved oxygen observed was 7.9 mg/L (milligrams per liter) at river mile 1.8. The lower limit allowed by the water-quality standard is 8 mg/L. Concentrations of dissolved oxygen measured in a cross section of the Puyallup River estuary at high tide on September 12, 2002, ranged from 9.9 to 10.2 mg/L in fresh water at the surface and from 8.1 to 8.4 mg/L in salt water near the riverbed. These values were within limits set by Washington State water-quality standards for dissolved oxygen of 8 mg/L in fresh water and 6 mg/L in marine water.
NASA Astrophysics Data System (ADS)
Leakey, Chris D. B.; Attrill, Martin J.; Fitzsimons, Mark F.
2009-04-01
Estuaries are regarded as valuable nursery habitats for many commercially important marine fishes, potentially providing a thermal resource, refuge from predators and a source of abundant prey. To assess the extent of estuarine use by juvenile (0+) common sole ( Solea solea), whiting ( Merlangius merlangus) and European seabass ( Dicentrarchus labrax) we: (1) developed techniques to distinguish between estuarine and coastally-caught juveniles using otolith chemistry; and (2) examined the accuracy with which multi-elemental signatures could re-classify juveniles to their region of collection. High-resolution solution-based inductively coupled plasma mass spectrometry (HB-SB-ICPMS) was used to quantify 32 elements within the juvenile otoliths; 14 elements occurred above detection limits for all samples. Some elemental distributions demonstrated clear differences between estuarine and coastally-caught fish. Multivariate analysis of the otolith chemistry data resulted in 95-100% re-classification accuracy to the region of collection. Estuarine and coastal signatures were most clearly defined for sole which, compared to bass and whiting, have low mobility and are less likely to move from estuarine to coastal habitats between larval settlement and later migration to adult stocks. Sole were the only species to reveal an energetic benefit associated with an estuarine juvenile phase. The physiological ability of bass to access upper estuarine regions was consistent with some elemental data, while the high mobility and restricted range of whiting resulted in less distinct otolith chemistries.
Odell, E W; Francis, C A; Eaton, K A; Reynolds, P A; Mason, R D
2001-08-01
Videoconferencing is an established method for providing medical education over long distances. Our aims were to assess the feasibility of videoconferencing in dental postgraduate education, to evaluate its practicability, teacher satisfaction and evaluate equipment. Twenty-seven teachers from the 4 London Dental Schools provided 41 postgraduate dental education sessions on a range of topics to regional postgraduate centres and dental practices as part of the Thames Health Region's programme. Videoconferencing was carried out using a relatively inexpensive personal computer system link using ISDN2 telephone lines and Z350 protocol. Presenter views and assessment were obtained by questionnaire, interview and videotape. Teachers felt that minimal additional preparation time was required for videoconferencing and 21/27 preferred it to in-person teaching, most noting the saving in travel time. Only 3 of the teachers were dissatisfied with their ability to communicate, 4 were equivocal and 20 were either pleased or very pleased. The teachers largely enjoyed the experience and performed well in the new medium. However, sound quality proved inadequate in 5/41 links and most sessions included some periods of suboptimal sound. Only 4 teachers were satisfied with their ability to perform question and answer interaction with the audience. We conclude that experienced teachers adapt readily to videoconferencing and learn to communicate effectively very quickly. Teachers were positive about the medium despite its shortcomings and improvements in sound quality would allow a rapid expansion of postgraduate dental education by videoconference.
Hilton, S; Rink, E; Fletcher, J; Sibbald, B; Freeling, P; Szczepura, A; Davies, C; Stilwell, J
1994-01-01
BACKGROUND. The evaluation of near patient testing in British general practice has largely been confined to studies examining individual tests or comparing equipment. AIM. This study set out to determine the attitudes of practice staff to near patient testing, and the extent to which staff undertook quality assessment. METHOD. Four types of near patient testing machines were introduced into 12 general practices in two regions of England, south west Thames and west Midlands. General practitioner and practice nurse attitudes to near patient testing were assessed by semi-structured interview before and six months after the introduction of the machines. The extent to which routine quality assurance procedures were carried out within the surgery and as part of local and national schemes was examined. RESULTS. Although 80% of general practitioners anticipated changing patient management with near patient testing, only two fifths reported having done so after six months. Nurses generally were enthusiastic at the outset, although one third were unhappy about incorporating near patient testing into their work schedules. Time pressure was the most important factor restricting uptake of near patient testing. Nurses performed quality control regularly but complete local external quality assurance procedures were established in only half the practices. All the practices participated in a national scheme for cholesterol assays. CONCLUSION. General practitioners in this study did not find near patient testing a very useful addition to their resources. Pressure on nurses' time was the most frequently reported limitation. PMID:7748669
Paediatric SpRs' experiences of breaking bad news.
Horwitz, N; Ellis, J
2007-09-01
To ascertain the level of support and training available to paediatric specialist registrars (SpRs) in breaking bad news and their self-reported confidence in this task. A questionnaire-based survey. Paediatric SpRs working in North Thames region. Specialist registrars (n = 206) were sent a questionnaire relating to the level of support and training available to them in breaking bad news and their attitudes to this task. A repeat questionnaire was sent out 2 weeks later. The response rate was 54.9%. The study sample included 78 females and 34 males. The median year of qualification was 1995 [interquartile range (IQR) 1993-1997] and the median year of Calman training was Year 3 (IQR 2-4). Only 15.9% of participants had guidelines where they worked and 91.2% had received training in breaking bad news. Median self-perceived confidence in breaking bad news was rated as 4 out of 5. Only 21.2% of all respondents had both disclosed a diagnosis of Down syndrome and received feedback on their performance from their seniors. Few SpRs were able to adhere to all evidence-based recommendations for breaking bad news. Most SpRs had received training in breaking bad news and self-reported confidence in this skill was high, although their hands-on experience was limited. Recent research shows, however, that parental dissatisfaction with the way in which bad news is broken remains high. The potential discrepancy between self-reported confidence and actual competence casts doubt on the value of self-evaluation.
Lallias, Delphine; Hiddink, Jan G; Fonseca, Vera G; Gaspar, John M; Sung, Way; Neill, Simon P; Barnes, Natalie; Ferrero, Tim; Hall, Neil; Lambshead, P John D; Packer, Margaret; Thomas, W Kelley; Creer, Simon
2015-01-01
Assessing how natural environmental drivers affect biodiversity underpins our understanding of the relationships between complex biotic and ecological factors in natural ecosystems. Of all ecosystems, anthropogenically important estuaries represent a ‘melting pot' of environmental stressors, typified by extreme salinity variations and associated biological complexity. Although existing models attempt to predict macroorganismal diversity over estuarine salinity gradients, attempts to model microbial biodiversity are limited for eukaryotes. Although diatoms commonly feature as bioindicator species, additional microbial eukaryotes represent a huge resource for assessing ecosystem health. Of these, meiofaunal communities may represent the optimal compromise between functional diversity that can be assessed using morphology and phenotype–environment interactions as compared with smaller life fractions. Here, using 454 Roche sequencing of the 18S nSSU barcode we investigate which of the local natural drivers are most strongly associated with microbial metazoan and sampled protist diversity across the full salinity gradient of the estuarine ecosystem. In order to investigate potential variation at the ecosystem scale, we compare two geographically proximate estuaries (Thames and Mersey, UK) with contrasting histories of anthropogenic stress. The data show that although community turnover is likely to be predictable, taxa are likely to respond to different environmental drivers and, in particular, hydrodynamics, salinity range and granulometry, according to varied life-history characteristics. At the ecosystem level, communities exhibited patterns of estuary-specific similarity within different salinity range habitats, highlighting the environmental sequencing biomonitoring potential of meiofauna, dispersal effects or both. PMID:25423027
Coverage of neonatal screening: failure of coverage or failure of information system
Ades, A; Walker, J; Jones, R; Smith, I
2001-01-01
OBJECTIVES—To evaluate neonatal screening coverage using data routinely collected on the laboratory computer. SUBJECTS—90 850 births in 14 North East Thames community provider districts over a 21 month period. METHODS—Births notified to local child health computers are electronically copied to the neonatal laboratory computer system, and incoming Guthrie cards are matched against these birth records before testing. The computer records for the study period were processed to estimate the coverage of the screening programme. RESULTS—Out of an estimated 90 850 births notified to child health computers, all but 746 (0.82%) appeared to have been screened or could be otherwise accounted for (0.14% in non-metropolitan districts, 0.39% in suburban districts, and 1.68% in inner city districts). A further 893 resident infants had been tested, but could not be matched to the list of notified resident births. The calculated programme coverage already exceeds the 99.5% National Audit Programme standard in 7/14 districts. Elsewhere it is not clear whether it is coverage or recording of coverage that is low. CONCLUSION—Previous reports of low coverage may have been exaggerated. High coverage can be shown using routine information systems. Design of information systems that deliver accurate measures of coverage would be more useful than comparison of inadequately measured coverage with a national standard. The new NHS number project will create an opportunity to achieve this. PMID:11369561
Problem based learning in midwifery - the teachers perspective.
Rowan, Catherine J; McCourt, Christine; Bick, Debra; Beake, Sarah
2007-02-01
Problem- or evidence-based learning (PBL or EBL) has become more widely used in the education of health professionals. Although there has been research exploring its effectiveness and the student's perspective, there has been little research exploring the perceptions of the teacher. The objective of this study was to investigate the experiences of teachers facilitating a problem based learning curriculum in midwifery. The study took place at Thames Valley University, which has implemented this approach across the entire curriculum. Semi-structured interviews were undertaken following random selection from two groups of teachers; those more experienced as teachers and those who had entered teaching more recently. Aspects of the teacher's role identified included questioning students to draw out their knowledge and understanding and to help students challenge each other, discuss and evaluate their learning. Strategies used varied depending on the stage of the programme. Difficulties encountered were mostly in relation to facilitating groups of differing backgrounds and ability and seeking to enable the students to work well together. Key challenges for teachers were in relation to developing facilitation skills, balancing input or guidance with facilitating independent learning. Problem based learning was perceived to be beneficial in helping students relate theory to practice and in encouraging an active and enquiring approach to evidence, but teachers raised important questions about its practice. Tensions were identified between the constructivist theories on which the model of PBL rests and the formal requirements of an externally regulated professional curriculum.
Dumelow, C; Littlejohns, P; Griffiths, S
2000-05-27
To explore the relation between work and family life among hospital consultants and their attitude towards the choices and constraints that influence this relation. Qualitative study of consultants' experiences and views based on tape recorded semistructured interviews. Former South Thames health region in southeast England. 202 male and female NHS hospital consultants aged between 40 to 50 years representing all hospital medical specialties. Three types of relation between work and family life (career dominant, segregated, and accommodating) were identified among hospital consultants. Most consultants had a segregated relation, although female consultants were more likely than male consultants to have a career dominant or an accommodating relation. Many male consultants and some female consultants expressed considerable dissatisfaction with the balance between their career and family life. A factor influencing this dissatisfaction was the perceived lack of choice to spend time on their personal or family life, because of the working practices and attitudes within hospital culture, if they wanted a successful career. Consultants are currently fitting in with the profession rather than the profession adapting to enable doctors to have fulfilling professional and personal lives. Current government policies to increase the medical workforce and promote family friendly policies in the NHS ought to take account of the need for a fundamental change in hospital culture to enable doctors to be more involved in their personal or family life without detriment to their career progress.
NASA Astrophysics Data System (ADS)
Harris, Peter T.
1988-06-01
Large-scale bedforms (2-10 m in vertical and 10 2-10 3 m in horizontal dimensions) found in wide-mouthed estuaries are described. Different bedform types occur depending upon the local availability of sand. With an increasing sand supply, sand ribbons grade into elongate trains of sand waves and then form sandwave fields. Inshore, headland-associated sand banks are formed which multiply into en-echelon sand banks. Based upon a review of data on directions of sand transport from the Bristol Channel and Thames Estuary, U.K., and from Moreton Bay, Australia, charts of ebb- and flood-dominant transport zones are constructed for lower estuarine environments which have undergone different degrees of infilling. Linear sand banks are seen to delimit partially the boundaries between opposing sand transport zones. Transport paths demonstrate how sediments derived from outside of the estuary are dispersed through ebb and flood transport zones, to supply other areas of net deposition. A comparison between different estuaries reveals that variations in the compexity of ebb- and flood-dominant transport zones and the morphologies of large-scale bedforms are coupled with apparent changes in the relative amounts of sand available to each system. A model for the sequential infilling of estuaries and the evolution of large-scale bedforms is presented and applied to the interpretation of present day examples. Vertical sequences predicted to be generated by such bedform evolution are described and discussed, in terms of their preservation in the geological record.
Impact of introducing near patient testing for standard investigations in general practice.
Rink, E; Hilton, S; Szczepura, A; Fletcher, J; Sibbald, B; Davies, C; Freeling, P; Stilwell, J
1993-01-01
OBJECTIVE--To assess the clinical and economic impact of surgery based near patient testing in general practice for six commonly used biochemical and bacteriological tests. DESIGN--After four months' monitoring, equipment for two bacteriological and four biochemical tests was introduced without cost into 12 practices using a crossover design. Structured request forms were used to monitor laboratory investigations. SETTING--12 general practices in west midlands and south west Thames with list sizes above 9000. MAIN OUTCOME MEASURES--Investigation rates per 1000 consultations. Changes from baseline rates. Reasons for requesting investigations and provisional diagnoses. Cost per test and sensitivity of costs to rate of use. RESULTS--Investigation rates for the six tests rose by 16.5% (from 78.6/1000 consultations to 91.6/1000) when equipment was available in the surgery and reverted to baseline rates when it was withdrawn. The average weekly number of tests when equipment was available ranged from 0.5 to 10.5 (mean 9.0). Cholesterol tests were used as an addition to laboratory testing, usually for screening. Midstream urine analysis was often done in the surgery instead of in the laboratory, although 30% of samples were tested by both methods. Doctors' reasons for investigation and conditions tested were largely unaffected by availability of surgery tests. Costs for surgery tests were higher for all tests except midstream urine. CONCLUSIONS--Availability of surgery based testing increased the number of tests performed. It was cost effective only for midstream urine analysis. PMID:8219952
Adaptive Flood Risk Management Under Climate Change Uncertainty Using Real Options and Optimization.
Woodward, Michelle; Kapelan, Zoran; Gouldby, Ben
2014-01-01
It is well recognized that adaptive and flexible flood risk strategies are required to account for future uncertainties. Development of such strategies is, however, a challenge. Climate change alone is a significant complication, but, in addition, complexities exist trying to identify the most appropriate set of mitigation measures, or interventions. There are a range of economic and environmental performance measures that require consideration, and the spatial and temporal aspects of evaluating the performance of these is complex. All these elements pose severe difficulties to decisionmakers. This article describes a decision support methodology that has the capability to assess the most appropriate set of interventions to make in a flood system and the opportune time to make these interventions, given the future uncertainties. The flood risk strategies have been explicitly designed to allow for flexible adaptive measures by capturing the concepts of real options and multiobjective optimization to evaluate potential flood risk management opportunities. A state-of-the-art flood risk analysis tool is employed to evaluate the risk associated to each strategy over future points in time and a multiobjective genetic algorithm is utilized to search for the optimal adaptive strategies. The modeling system has been applied to a reach on the Thames Estuary (London, England), and initial results show the inclusion of flexibility is advantageous, while the outputs provide decisionmakers with supplementary knowledge that previously has not been considered. © 2013 HR Wallingford Ltd.
49 CFR Appendix B to Part 194 - High Volume Areas
Code of Federal Regulations, 2010 CFR
2010-10-01
.... Mississippi River Woodriver, IL. Mississippi River St. James, LA. Mississippi River New Roads, LA. Mississippi River Ball Club, MN. Mississippi River Mayersville, MS. Mississippi River New Roads, LA. Mississippi... Arthur Kill Channel, NY Cook Inlet, AK Freeport, TX Los Angeles/Long Beach Harbor, CA Port Lavaca, TX San...
Code of Federal Regulations, 2010 CFR
2010-07-01
...) Mississippi River between its sources and mile 235, Above Head of Passes; (ii) Tributaries emptying into the Mississippi River above mile 235; (iii) Atchafalaya River above its junction with the Plaquemine-Morgan City alternate waterway and the Red River; and (iv) The Tennessee River from its confluence with the Ohio River...
36 CFR 292.62 - Valid existing rights.
Code of Federal Regulations, 2010 CFR
2010-07-01
... RECREATION AREAS Smith River National Recreation Area § 292.62 Valid existing rights. (a) Definition. For the... “wild” segments of the Wild and Scenic Smith River, Middle Fork Smith River, North Fork Smith River, Siskiyou Fork Smith River, South Fork Smith River, and their designated tributaries, except Peridotite...
78 FR 48813 - Final Flood Elevation Determinations
Federal Register 2010, 2011, 2012, 2013, 2014
2013-08-12
... Unincorporated Areas of Green River). the Green River to Butler County. approximately 0.6 mile upstream of the... with +428 Unincorporated Areas of Green River). the Green River to Butler County. approximately 0.5... with +433 Unincorporated Areas of Green River). the Green River to Butler County. approximately 1,202...
33 CFR 165.150 - New Haven Harbor, Quinnipiac River, Mill River.
Code of Federal Regulations, 2010 CFR
2010-07-01
... River, Mill River. 165.150 Section 165.150 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF... New Haven Harbor, Quinnipiac River, Mill River. (a) The following is a regulated navigation area: The... 303°T to point D at the west bank of the mouth of the Mill River 41°18′05″ N, 72°54′23″ W thence south...
Meng, Qingpeng; Zhang, Jing; Zhang, Zhaoyu; Wu, Tairan
2016-04-01
Dissolved trace elements and heavy metals in the Dan River drainage basin, which is the drinking water source area of South-to-North Water Transfer Project (China), affect large numbers of people and should therefore be carefully monitored. To investigate the distribution, sources, and quality of river water, this study integrating catchment geology and multivariate statistical techniques was carried out in the Dan River drainage from 99 river water samples collected in 2013. The distribution of trace metal concentrations in the Dan River drainage was similar to that in the Danjiangkou Reservoir, indicating that the reservoir was significantly affected by the Dan River drainage. Moreover, our results suggested that As, Sb, Cd, Mn, and Ni were the major pollutants. We revealed extremely high concentrations of As and Sb in the Laoguan River, Cd in the Qingyou River, Mn, Ni, and Cd in the Yinhua River, As and Sb in the Laojun River, and Sb in the Dan River. According to the water quality index, water in the Dan River drainage was suitable for drinking; however, an exposure risk assessment model suggests that As and Sb in the Laojun and Laoguan rivers could pose a high risk to humans in terms of adverse health and potential non-carcinogenic effects.
Jaeger, Kristin L.; Curran, Christopher A.; Anderson, Scott W.; Morris, Scott T.; Moran, Patrick W.; Reams, Katherine A.
2017-11-01
The Sauk River is a federally designated Wild and Scenic River that drains a relatively undisturbed landscape along the western slope of the North Cascade Mountain Range, Washington, which includes the glaciated volcano, Glacier Peak. Naturally high sediment loads characteristic of basins draining volcanoes like Glacier Peak make the Sauk River a dominant contributor of sediment to the downstream main stem river, the Skagit River. Additionally, the Sauk River serves as important spawning and rearing habitat for several salmonid species in the greater Skagit River system. Because of the importance of sediment to morphology, flow-conveyance, and ecosystem condition, there is interest in understanding the magnitude and timing of suspended sediment and turbidity from the Sauk River system and its principal tributaries, the White Chuck and Suiattle Rivers, to the Skagit River.Suspended-sediment measurements, turbidity data, and water temperature data were collected at two U.S. Geological Survey streamgages in the upper and middle reaches of the Sauk River over a 4-year period extending from October 2011 to September 2015, and at a downstream location in the lower river for a 5-year period extending from October 2011 to September 2016. Over the collective 5-year study period, mean annual suspended-sediment loads at the three streamgages on the upper, middle, and lower Sauk River streamgages were 94,200 metric tons (t), 203,000 t, and 940,000 t streamgages, respectively. Fine (smaller than 0.0625 millimeter) total suspended-sediment load averaged 49 percent at the upper Sauk River streamgage, 42 percent at the middle Sauk River streamgage, and 34 percent at the lower Sauk River streamgage.
Pan, Xiao-xue; Ma, Ying-qun; Qin, Yan-wen; Zou, Hua
2015-08-01
Overall 20 surface water samples were collected from the Yangtze River, the Wangyu River and the Gonghu Bay (Lake Taihu) to clarify the pollution characteristics of nitrogen and phosphorus during 2 sample stages of "Water Transfers on Lake Taihu from the Yangtze River" in August and December of 2013 respectively. The results showed that the mass concentrations of NO2- -N, NO3- -N, NH4+ -N and TN in the Gonghu Bay were lower than those of the Yangtze River and Wangyu River during the 2 water transfer processes. However, there was higher level of DON content in the Gonghu Bay than that of the Yangtze River and Wangyu River. The percentages of various N species showed that NO3- -N was the major N species in the Yangtze River and Wangyu River during the 2 water transfer processes. TP contents in samples collected from the Yangtze River displayed a constant trend compared with the Wangyu River. However, the percentages of various P species were different with each other during the 2 water transfer processes. Mass concentrations of DON and TP in surface water in August were higher than those in December and the contents of NO3- -N and TDP were lower in August than those in December. In general, NO3- -N and TPP were the main N and P species in Wangyu River from the Yangtze River. NO3- -N, PO4(3-) -P and TPP were the main N and P species in Gonghu Bay from Wangyu River during the 2 water transfer processes.
River mouth morphodynamics - Examples from small, mountainous rivers (Invited)
NASA Astrophysics Data System (ADS)
Warrick, J. A.
2013-12-01
Small, high-sediment yield rivers are known to discharge massive amounts of sediment to the world's oceans. Because of these high rates of sediment discharge, many of these small rivers provide important sources of sediment to littoral cells, such as those along the west coasts of North and South America. Sediment discharge from these small watersheds is commonly ephemeral and dominated by infrequent high flow. Thus, the morphodynamic states of these river mouths will vary with time, often being 'wave dominated' for the majority of the year and then changing to 'river dominated' during river sediment discharge events. Here I will provide a summary of recent observations of the morphodynamics of river mouths along California that reveal that sediment dispersal and deposition patterns vary owing to the sediment transport processes at the river mouths, which are influenced by the buoyancy of the river discharge. During low rates of sediment discharge and low river sediment concentrations, sediment dispersal will occur in hypopycnal (positively buoyant) plumes and sand deposition will be close to the river mouth. These conditions commonly result in transfer of sand from the river delta to the littoral cell during the first 1-2 years following the river discharge event. During high rates of sediment discharge and high river sediment concentrations, river discharge may form hyperpycnal (negatively buoyant) plumes and disperse sand to deeper portions of the continental shelf, where transfer back to the littoral cell may take decades or may not occur. High-resolution bathymetry from southern California provides several examples of sand dispersal by hyperpycnal plumes to regions of the inner and middle continental shelf. Thus, sediment dispersal from river mouths influences coastal morphodynamics, morphology, and the rates and timing of sediment supply to littoral cells.
Accumulated state assessment of the Peace-Athabasca-Slave River system.
Dubé, Monique G; Wilson, Julie E
2013-07-01
Effects-based analysis is a fundamental component of watershed cumulative effects assessment. This study conducted an effects-based analysis for the Peace-Athabasca-Slave River System, part of the massive Mackenzie River Basin, encompassing 20% of Canada's total land mass and influenced by cumulative contributions of the W.A.C. Bennett Dam (Peace River) and industrial activities including oil sands mining (Athabasca River). This study assessed seasonal changes in 1) Peace River water quality and quantity before and after dam development, 2) Athabasca River water quality and quantity before and after oil sands developments, 3) tributary inputs from the Peace and Athabasca Rivers to the Slave River, and 4) upstream to downstream differences in water quality in the Slave River. In addition, seasonal benchmarks were calculated for each river based on pre-perturbation post-perturbation data for future cumulative effects assessments. Winter discharge (January-March) from the Peace and Slave Rivers was significantly higher than before dam construction (pre-1967) (p < 0.05), whereas summer peak flows (May-July) were significantly lower than before the dam showing that regulation has significantly altered seasonal flow regimes. During spring freshet and summer high flows, the Peace River strongly influenced the quality of the Slave River, as there were no significant differences in loadings of dissolved N, total P (TP), total organic C (TOC), total As, total Mn, total V, and turbidity and specific conductance between these rivers. In the Athabasca River, TP and specific conductance concentrations increased significantly since before oil sands developments (1967-2010), whereas dissolved N and sulfate have increased after the oil sands developments (1977-2010). Recently, the Athabasca River had significantly higher concentrations of dissolved N, TP, TOC, dissolved sulfate, specific conductance, and total Mn than either the Slave or the Peace Rivers during the winter months. The transboundary nature of the Peace, Athabasca, and Slave River basins has resulted in fragmented monitoring and reporting of the state of these rivers, and a more consistent monitoring framework is recommended. Copyright © 2012 SETAC.
NASA Astrophysics Data System (ADS)
Xu, Y. J.
2016-02-01
Dujiangyan, also known as the Dujiangyan Project, is a hydraulic engineering complex built more than 2260 years ago on the Mingjiang River near Chengdu in China's Sichuan Province. The complex splits the river into two channels, a so-called "inner river" (Leijiang) and an "outer river" (Waijiang) that carry variable water volumes and sediment loads under different river flow conditions. The inner river and its numerous distributary canals are primarily man-made for irrigation over the past 2000 years, while the outer river is the natural channel and flows southward before entering into the Yangtze River. Under normal flow, 60% of the Mingjiang River goes into the inner river for irrigating nearly 1 million hectares of agricultural land on the Chengdu plain. During floods, however, less than 40% of the Mingjiang River flows into the inner river. Under both flow conditions, about 80% of the riverine sediments is carried by the outer river and continues downstream. This hydrology is achieved through a weir work complex that comprises three major components: a V-shaped bypass dike in the center of the Mingjiang River (the Yuzui Bypass Dike, see photo below), a sediment diversion canal in the inner river below the bypass dike (the Feishayan Floodgate), and a flow control in the inner river below the sediment diversion canal (the Baopingkou Diversion Passage). Together with ancillary embankments, these structures have not only ensured a regular supply of silt-reduced water to the fertile Chengdu plain, but have provided great benefits in flood control, sediment transport, and water resources regulation over the past two thousand years. The design of this ancient hydraulic complex ingeniously conforms to the natural environment while incorporating many sophisticated techniques, reflecting the concept that humankind is an integral part of nature. As we are urgently seeking solutions today to save the sinking Mississippi River Delta, examination of the ancient engineering marvel may offer insights into sustainable practices in river engineering of the lower Mississippi under climate change and sea level rise. This paper will introduce the Dujiangyan Project and will discuss possibilities of applying Dujiangyan's fundamental concept for sediment diversions in the Lower Mississippi River.
Owen-Joyce, Sandra J.; Wilson, Richard P.; Carpenter, Michael C.; Fink, James B.
2000-01-01
Accounting for the use of Colorado River water is required by the U.S. Supreme Court decree, 1964, Arizona v. California. Water pumped from wells on the flood plain and from certain wells on alluvial slopes outside the flood plain is presumed to be river water and is accounted for as Colorado River water. The accounting-surface method developed for the area upstream from Laguna Dam was modified for use downstream from Laguna Dam to identify wells outside the flood plain of the lower Colorado River that yield water that will be replaced by water from the river. Use of the same method provides a uniform criterion of identification for all users pumping water from wells by determining if the static water-level elevation in the well is above or below the elevation of the accounting surface. Wells that have a static water-level elevation equal to or below the accounting surface are presumed to yield water that will be replaced by water from the Colorado River. Wells that have a static water-level elevation above the accounting surface are presumed to yield river water stored above river level. The method is based on the concept of a river aquifer and an accounting surface within the river aquifer. The river aquifer consists of permeable sediments and sedimentary rocks that are hydraulically connected to the Colorado River so that water can move between the river and the aquifer in response to withdrawal of water from the aquifer or differences in water-level elevations between the river and the aquifer. The subsurface limit of the river aquifer is the nearly impermeable bedrock of the bottom and sides of the basins that underlie the Yuma area and adjacent valleys. The accounting surface represents the elevation and slope of the unconfined static water table in the river aquifer outside the flood plain of the Colorado River that would exist if the river were the only source of water to the river aquifer. The accounting surface was generated by using water-surface profiles of the Colorado River from Laguna Dam to about the downstream limit of perennial flow at Morelos Dam. The accounting surface extends outward from the edges of the flood plain to the subsurface boundary of the river aquifer. Maps at a scale of 1:100,000 show the extent of the river aquifer and elevation of the accounting surface downstream from Laguna Dam in Arizona and California.
Pawcatuck and Woonasquatucket River Basins and Narragansett Bay Local Drainage Area. Main Report.
1981-10-01
building and housing codes are recommended. Flood warning systems, urban renewal, tax incentives, and public open space acquisition will also help...RIVER GROUP WATERSHEDLD LOCAL DRAINAGE PD, WOONASQUATUCKET - MOSI4ASSUCK - PROVIDENCE RIVERS SUB-BASIN PD2 BLACKSTONE RIVER SUB-BASIN orPD 3 TENMiLE...of the Taunton River Basin in Massachusetts, 1979 PNB Water Supply Study, January 1979 Big River Reservoir Project, July 1981 Blackstone River
This curriculum was developed as a significant component of the project, Always a River: The Ohio River and the American Experience, a six-state collaboration devoted to exploring the historical and cultural development of the Ohio River. The Always a River project is being joint...
78 FR 49918 - Drawbridge Operation Regulation; Taunton River, Fall River and Somerset, MA
Federal Register 2010, 2011, 2012, 2013, 2014
2013-08-16
... DEPARTMENT OF HOMELAND SECURITY Coast Guard 33 CFR Part 117 [Docket No. USCG-2013-0291] RIN 1625-AA09 Drawbridge Operation Regulation; Taunton River, Fall River and Somerset, MA AGENCY: Coast Guard... Operation Regulation: Taunton River, Fall River and Somerset, MA'' in the Federal Register (78 FR 31457). We...
33 CFR 117.353 - Atlantic Intracoastal Waterway, Savannah River to St. Marys River.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Atlantic Intracoastal Waterway, Savannah River to St. Marys River. 117.353 Section 117.353 Navigation and Navigable Waters COAST GUARD....353 Atlantic Intracoastal Waterway, Savannah River to St. Marys River. (a) General. Public vessels of...
75 FR 51945 - Safety Zone; Potomac River, St. Mary's River, St. Inigoes, MD
Federal Register 2010, 2011, 2012, 2013, 2014
2010-08-24
...-AA00 Safety Zone; Potomac River, St. Mary's River, St. Inigoes, MD AGENCY: Coast Guard, DHS. ACTION... of the St. Mary's River, a tributary of the Potomac River. This action is necessary to provide for.... Navy helicopter located near St. Inigoes, Maryland. This safety zone is intended to protect the...
33 CFR 117.911 - Atlantic Intracoastal Waterway, Little River to Savannah River.
Code of Federal Regulations, 2014 CFR
2014-07-01
..., Little River to Savannah River. 117.911 Section 117.911 Navigation and Navigable Waters COAST GUARD... § 117.911 Atlantic Intracoastal Waterway, Little River to Savannah River. (a) General. Public vessels of.... 16, 1985] Editorial Note: For Federal Register citations affecting § 117.911, see the List of CFR...
33 CFR 117.911 - Atlantic Intracoastal Waterway, Little River to Savannah River.
Code of Federal Regulations, 2013 CFR
2013-07-01
..., Little River to Savannah River. 117.911 Section 117.911 Navigation and Navigable Waters COAST GUARD... § 117.911 Atlantic Intracoastal Waterway, Little River to Savannah River. (a) General. Public vessels of.... 16, 1985] Editorial Note: For Federal Register citations affecting § 117.911, see the List of CFR...
33 CFR 117.911 - Atlantic Intracoastal Waterway, Little River to Savannah River.
Code of Federal Regulations, 2010 CFR
2010-07-01
..., Little River to Savannah River. 117.911 Section 117.911 Navigation and Navigable Waters COAST GUARD... § 117.911 Atlantic Intracoastal Waterway, Little River to Savannah River. (a) General. Public vessels of.... 16, 1985] Editorial Note: For Federal Register citations affecting § 117.911, see the List of CFR...
33 CFR 117.911 - Atlantic Intracoastal Waterway, Little River to Savannah River.
Code of Federal Regulations, 2012 CFR
2012-07-01
..., Little River to Savannah River. 117.911 Section 117.911 Navigation and Navigable Waters COAST GUARD... § 117.911 Atlantic Intracoastal Waterway, Little River to Savannah River. (a) General. Public vessels of.... 16, 1985] Editorial Note: For Federal Register citations affecting § 117.911, see the List of CFR...
33 CFR 117.911 - Atlantic Intracoastal Waterway, Little River to Savannah River.
Code of Federal Regulations, 2011 CFR
2011-07-01
..., Little River to Savannah River. 117.911 Section 117.911 Navigation and Navigable Waters COAST GUARD... § 117.911 Atlantic Intracoastal Waterway, Little River to Savannah River. (a) General. Public vessels of... Register citations affecting § 117.911, see the List of CFR Sections Affected, which appears in the Finding...
33 CFR 125.06 - Western rivers.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Western rivers. 125.06 Section... VESSELS § 125.06 Western rivers. The term western rivers as used in the regulations in this subchapter shall include only the Red River of the North, the Mississippi River and its tributaries above the Huey...
4. SNAKE RIVER VALLEY IRRIGATION DISTRICT, PHOTOGRAPHIC COPY OF DRAWING, ...
4. SNAKE RIVER VALLEY IRRIGATION DISTRICT, PHOTOGRAPHIC COPY OF DRAWING, PROPOSED SECTION OF DIVERSION DAM ACROSS SNAKE RIVER, SHEET 1 OF 5, 1924 (on file at the Idaho State Office of Water Resources, Boise, Idaho) - Snake River Valley Irrigation District, East Side of Snake River (River Mile 796), Shelley, Bingham County, ID
78 FR 53666 - Drawbridge Operation Regulation; Wolf River, Gills Landing and Winneconne, WI
Federal Register 2010, 2011, 2012, 2013, 2014
2013-08-30
... the Upper Fox River. The Wolf River has two drawbridges over the waterway. The Winneconne Highway... the Fox River that connect directly with the Wolf River. This rule will establish consistent operating... by WDOT and Fox River Valley Navigation Authority for the past 10 to 15 years. These agencies, along...
Altenritter, Matthew E.; Zydlewski, Gayle B.; Kinnison, Michael T.; Zydlewski, Joseph D.; Wippelhauser, Gail S.
2018-01-01
Movement of shortnose sturgeon (Acipenser brevirostrum) among major river systems in the Gulf of Maine is common and has implications for the management of this endangered species. Directed movements of 61 telemetered individuals monitored between 2010 and 2013 were associated with the river of tagging and individual characteristics. While a small proportion of fish tagged in the Kennebec River moved to the Penobscot River (5%), a much higher proportion of fish tagged in the Penobscot River moved to the Kennebec River (66%), during probable spawning windows. This suggests that Penobscot River fish derive from a migratory contingent within a larger Kennebec River population. Despite this connectivity, fish captured in the Penobscot River were larger (∼100 mm fork length) and had higher condition factors (median Fulton’s K: 0.76) than those captured in the Kennebec River (median Fulton’s K: 0.61). Increased abundance and resource limitation in the Kennebec River may be constraining growth and promoting migration to the Penobscot River by individuals with sufficient initial size and condition. Migrants could experience an adaptive reproductive advantage relative to nonmigratory individuals.
RIVER LEVEL ESTIMATION USING ARTIFICIAL NEURAL NETWORK FOR URBAN SMALL RIVER IN TIDAL REACH
NASA Astrophysics Data System (ADS)
Takasaki, Tadakatsu; Kawamura, Akira; Amaguchi, Hideo
Prediction of water level in small rivers is great interest for flood control in an urban area located in the river mouth. The tidal river water level is affected by not only flood discharge but also tide, atmospheric pressure, wind direction and speed. We propose a method of estimating river water level considering these factors using an artificial neural network model for the Kanda River located in the center of Tokyo. The effects by those factors are quantitatively investigated. As for the effects by the atmospheric pressure, river water level rises about 7cm per 5hPa increase of the pressure regardless of river discharge under the conditions of 1m/s wind speed and north wind direction. The accurate rating curve for the tidal river is finally obtained.
Dispersal scaling from the world's rivers
Warrick, J.A.; Fong, D.A.
2004-01-01
Although rivers provide important biogeochemical inputs to oceans, there are currently no descriptive or predictive relationships of the spatial scales of these river influences. Our combined satellite, laboratory, field and modeling results show that the coastal dispersal areas of small, mountainous rivers exhibit remarkable self-similar scaling relationships over many orders of magnitude. River plume areas scale with source drainage area to a power significantly less than one (average = 0.65), and this power relationship decreases significantly with distance offshore of the river mouth. Observations of plumes from large rivers reveal that this scaling continues over six orders of magnitude of river drainage basin areas. This suggests that the cumulative area of coastal influence for many of the smallest rivers of the world is greater than that of single rivers of equal watershed size. Copyright 2004 by the American Geophysical Union.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cochnauer, Tim; Claire, Christopher
2009-05-07
Pacific lamprey Lampetra tridentata have received little attention in fishery science until recently, even though abundance has declined significantly along with other anadromous fish species in Idaho. Pacific lamprey in Idaho have to navigate over eight lower Snake River and Columbia River hydroelectric facilities for migration downstream as juveniles to the Pacific Ocean and again as adults migrating upstream to their freshwater spawning grounds in Idaho. The number of adult Pacific lamprey annually entering the Snake River basin at Ice Harbor Dam has declined from an average of over 18,000 during 1962-1969 to fewer than 600 during 1998-2006. Based onmore » potential accessible streams and adult escapement over Lower Granite Dam on the lower Snake River, we estimate that no more than 200 Pacific lamprey adult spawners annually utilize the Clearwater River drainage in Idaho for spawning. We utilized electrofishing in 2000-2006 to capture, enumerate, and obtain biological information regarding rearing Pacific lamprey ammocoetes and macropthalmia to determine the distribution and status of the species in the Clearwater River drainage, Idaho. Present distribution in the Clearwater River drainage is limited to the lower sections of the Lochsa and Selway rivers, the Middle Fork Clearwater River, the mainstem Clearwater River, the South Fork Clearwater River, and the lower 7.5 km of the Red River. In 2006, younger age classes were absent from the Red River.« less
NASA Astrophysics Data System (ADS)
Wei, R.; Frasson, R. P. M.; Williams, B. A.; Rodriguez, E.; Pavelsky, T.; Altenau, E. H.; Durand, M. T.
2017-12-01
The upcoming Surface Water and Ocean Topography (SWOT) mission will measure river widths and water surface elevations of rivers wider than 100 m. In preparation for the SWOT mission, the Jet Propulsion Laboratory built the SWOT hydrology simulator with the intent of generating synthetic SWOT overpasses over rivers with realistic error characteristics. These synthetic overpasses can be used to guide the design of processing methods and data products, as well as develop data assimilation techniques that will incorporate the future SWOT data into hydraulic and hydrologic models as soon as the satellite becomes operational. SWOT simulator uses as inputs water depth, river bathymetry, and the surrounding terrain digital elevation model to create simulated interferograms of the study area. Next, the simulator emulates the anticipated processing of SWOT data by attempting to geolocate and classify the radar returns. The resulting cloud of points include information on water surface elevation, pixel area, and surface classification (land vs water). Finally, we process the pixel clouds by grouping pixels into equally spaced nodes located at the river centerline. This study applies the SWOT simulator to six different rivers: Sacramento River, Tanana River, Saint Lawrence River, Platte River, Po River, and Amazon River. This collection of rivers covers a range of size, slope, and planform complexity with the intent of evaluating the impact of river width, slope, planform complexity, and surrounding topography on the anticipated SWOT height, width, and slope error characteristics.
Summary of Bed-Sediment Measurements Along the Platte River, Nebraska, 1931-2009
Kinzel, P.J.; Runge, J.T.
2010-01-01
Rivers are conduits for water and sediment supplied from upstream sources. The sizes of the sediments that a river bed consists of typically decrease in a downstream direction because of natural sorting. However, other factors can affect the caliber of bed sediment including changes in upstream water-resource development, land use, and climate that alter the watershed yield of water or sediment. Bed sediments provide both a geologic and stratigraphic record of past fluvial processes and quantification of current sediment transport relations. The objective of this fact sheet is to describe and compare longitudinal measurements of bed-sediment sizes made along the Platte River, Nebraska from 1931 to 2009. The Platte River begins at the junction of the North Platte and South Platte Rivers near North Platte, Nebr. and flows east for approximately 500 kilometers before joining the Missouri River at Plattsmouth, Nebr. The confluence of the Loup River with the Platte River serves to divide the middle (or central) Platte River (the Platte River upstream from the confluence with the Loup River) and lower Platte River (the Platte River downstream from the confluence with Loup River). The Platte River provides water for a variety of needs including: irrigation, infiltration to public water-supply wells, power generation, recreation, and wildlife habitat. The Platte River Basin includes habitat for four federally listed species including the whooping crane (Grus americana), interior least tern (Sterna antillarum), piping plover (Charadrius melodus), and pallid sturgeon (Scaphirhynchus albus). A habitat recovery program for the federally listed species in the Platte River was initiated in 2007. One strategy identified by the recovery program to manage and enhance habitat is the manipulation of streamflow. Understanding the longitudinal and temporal changes in the size gradation of the bed sediment will help to explain the effects of past flow regimes and anticipated manipulation of streamflows on the channel morphology and habitat.
Coherence between coastal and river flooding along the California coast
Odigie, Kingsley O.; Warrick, Jonathan
2018-01-01
Water levels around river mouths are intrinsically determined by sea level and river discharge. If storm-associated coastal water-level anomalies coincide with extreme river discharge, landscapes near river mouths will be flooded by the hydrodynamic interactions of these two water masses. Unfortunately, the temporal relationships between ocean and river water masses are not well understood. The coherence between extreme river discharge and coastal water levels at six California river mouths across different climatic and geographic regions was examined. Data from river gauges, wave buoys, and tide gauges from 2007 to 2014 were integrated to investigate the relationships between extreme river discharge and coastal water levels near the mouths of the Eel, Russian, San Lorenzo, Ventura, Arroyo Trabuco, and San Diego rivers. Results indicate that mean and extreme coastal water levels during extreme river discharge are significantly higher compared with background conditions. Elevated coastal water levels result from the combination of nontidal residuals (NTRs) and wave setups. Mean and extreme (>99th percentile of observations) NTRs are 3–20 cm and ∼30 cm higher during extreme river discharge conditions, respectively. Mean and extreme wave setups are up to 40 cm and ∼20–90 cm higher during extreme river discharge than typical conditions, respectively. These water-level anomalies were generally greatest for the northern rivers and least for the southern rivers. Time-series comparisons suggest that increases in NTRs are largely coherent with extreme river discharge, owing to the low atmospheric pressure systems associated with storms. The potential flooding risks of the concurrent timing of these water masses are tempered by the mixed, semidiurnal tides of the region that have amplitudes of 2–2.5 m. In summary, flooding hazard assessments for floodplains near California river mouths for current or future conditions with sea-level rise should include the temporal coherence of fluvial and oceanic water levels.
Setiawan, B B
2002-01-01
The settlement along the bank of the Code River in Yogyakarta, Indonesia provides housing for a large mass of the city's poor. Its strategic location and the fact that most urban poor do not have access to land, attracts people to "illegally" settle along the bank of the river. This brings negative consequences for the environment, particularly the increasing domestic waste along the river and the annual flooding in the rainy season. While the public controversies regarding the existence of the settlement along the Code River were still not resolved, at the end of the 1980s, a group of architects, academics and community members proposed the idea of constructing a dike along the River as part of a broader settlement improvement program. From 1991 to 1998, thousands of local people mobilized their resources and were able to construct 6,000 metres of riverside dike along the Code River. The construction of the riverside dike along the River has become an important "stimulant" that generated not only settlement improvement, but also a better treatment of river water. As all housing units located along the River are now facing the River, the River itself is considered the "front-yard". Before the dike was constructed, the inhabitants used to treat the River as the "backyard" and therefore just throw waste into the River. They now really want to have a cleaner river, since the River is an important part of their settlement. The settlement along the Code River presents a complex range of persistent problems with informal settlements in Indonesia; such problems are related to the issues of how to provide more affordable and adequate housing for the poor, while at the same time, to improve the water quality of the river. The project represents a good case, which shows that through a mutual partnership among stakeholders, it is possible to integrate environmental goals into urban redevelopment schemes.
The Role of Forests in Regulating the River Flow Regime of Large Basins of the World
NASA Astrophysics Data System (ADS)
Salazar, J. F.; Villegas, J. C.; Mercado-Bettin, D. A.; Rodríguez, E.
2016-12-01
Many natural and social phenomena depend on river flow regimes that are being altered by global change. Understanding the mechanisms behind such alterations is crucial for predicting river flow regimes in a changing environment. Here we explore potential linkages between the presence of forests and the capacity of river basins for regulating river flows. Regulation is defined here as the capacity of river basins to attenuate the amplitude of the river flow regime, that is to reduce the difference between high and low flows. We first use scaling theory to show how scaling properties of observed river flows can be used to classify river basins as regulated or unregulated. This parsimonious classification is based on a physical interpretation of the scaling properties (particularly the scaling exponents) that is novel (most previous studies have focused on the interpretation of the scaling exponents for floods only), and widely-applicable to different basins (the only assumption is that river flows in a given river basin exhibit scaling properties through well-known power laws). Then we show how this scaling framework can be used to explore global-change-induced temporal variations in the regulation capacity of river basins. Finally, we propose a conceptual hypothesis (the "Forest reservoir concept") to explain how large-scale forests can exert important effects on the long-term water balance partitioning and regulation capacity of large basins of the world. Our quantitative results are based on data analysis (river flows and land cover features) from 22 large basins of the world, with emphasis in the Amazon river and its main tributaries. Collectively, our findings support the hypothesis that forest cover enhances the capacity of large river basins to maintain relatively high mean river flows, as well as to regulate (ameliorate) extreme river flows. Advancing towards this quantitative understanding of the relation between forest cover and river flow regimes is crucial for water management- and land cover-related decisions.
The Role of Forests in Regulating the River Flow Regime of Large Basins of the World
NASA Astrophysics Data System (ADS)
Salazar, J. F.; Villegas, J. C.; Mercado-Bettin, D. A.; Rodríguez, E.
2017-12-01
Many natural and social phenomena depend on river flow regimes that are being altered by global change. Understanding the mechanisms behind such alterations is crucial for predicting river flow regimes in a changing environment. Here we explore potential linkages between the presence of forests and the capacity of river basins for regulating river flows. Regulation is defined here as the capacity of river basins to attenuate the amplitude of the river flow regime, that is to reduce the difference between high and low flows. We first use scaling theory to show how scaling properties of observed river flows can be used to classify river basins as regulated or unregulated. This parsimonious classification is based on a physical interpretation of the scaling properties (particularly the scaling exponents) that is novel (most previous studies have focused on the interpretation of the scaling exponents for floods only), and widely-applicable to different basins (the only assumption is that river flows in a given river basin exhibit scaling properties through well-known power laws). Then we show how this scaling framework can be used to explore global-change-induced temporal variations in the regulation capacity of river basins. Finally, we propose a conceptual hypothesis (the "Forest reservoir concept") to explain how large-scale forests can exert important effects on the long-term water balance partitioning and regulation capacity of large basins of the world. Our quantitative results are based on data analysis (river flows and land cover features) from 22 large basins of the world, with emphasis in the Amazon river and its main tributaries. Collectively, our findings support the hypothesis that forest cover enhances the capacity of large river basins to maintain relatively high mean river flows, as well as to regulate (ameliorate) extreme river flows. Advancing towards this quantitative understanding of the relation between forest cover and river flow regimes is crucial for water management- and land cover-related decisions.
NASA Astrophysics Data System (ADS)
Lakshmi, V.; Sen, I. S.; Mishra, G.
2017-12-01
There has been much discussion amongst biologists, ecologists, chemists, geologists, environmental firms, and science policy makers about the impact of human activities on river health. As a result, multiple river restoration projects are on going on many large river basins around the world. In the Indian subcontinent, the Ganges River is the focal point of all restoration actions as it provides food and water security to half a billion people. Serious concerns have been raised about the quality of Ganga water as toxic chemicals and many more enters the river system through point-sources such as direct wastewater discharge to rivers, or non-point-sources. Point source pollution can be easily identified and remedial actions can be taken; however, non-point pollution sources are harder to quantify and mitigate. A large non-point pollution source in the Indo-Gangetic floodplain is the network of small floodplain rivers. However, these rivers are rarely studied since they are small in catchment area ( 1000-10,000 km2) and discharge (<100 m3/s). As a result, the impact of these small floodplain rivers on the dissolved chemical load of large river systems is not constrained. To fill this knowledge gap we have monitored the Pandu River for one year between February 2015 and April 2016. Pandu river is 242 km long and is a right bank tributary of Ganges with a total catchment area of 1495 km2. Water samples were collected every month for dissolved major and trace elements. Here we show that the concentration of heavy metals in river Pandu is in higher range as compared to the world river average, and all the dissolved elements shows a large spatial-temporal variation. We show that the Pandu river exports 192170, 168517, 57802, 32769, 29663, 1043, 279, 241, 225, 162, 97, 28, 25, 22, 20, 8, 4 Kg/yr of Ca, Na, Mg, K, Si, Sr, Zn, B, Ba, Mn, Al, Li, Rb, Mo, U, Cu, and Sb, respectively, to the Ganga river, and the exported chemical flux effects the water chemistry of the Ganga river downstream of its confluence point. We further speculate that small floodplain rivers is an important source that contributes to the dissolved chemical budget of large river systems, and they must be better monitored to address future challenges in river basin management.
Hughes, Curt A.
2003-01-01
Instantaneous arsenic loads calculated for August 1999 were similar to mean monthly loads determined in August 1989 at two intensive fixed sites located on the Yakima main stem. In August 1999, arsenic loads increased twofold between the Yakima River at river mile 72 above Satus and the Yakima River at Kiona at river mile 29.9. The dissolved arsenic loads for the Yakima River at Euclid Bridge at river mile 55 near Grandview and Yakima River at Kiona were within 13 percent of the August 1989 levels.
A drifter for measuring water turbidity in rivers and coastal oceans.
Marchant, Ross; Reading, Dean; Ridd, James; Campbell, Sean; Ridd, Peter
2015-02-15
A disposable instrument for measuring water turbidity in rivers and coastal oceans is described. It transmits turbidity measurements and position data via a satellite uplink to a processing server. The primary purpose of the instrument is to help document changes in sediment runoff from river catchments in North Queensland, Australia. The 'river drifter' is released into a flooded river and drifts downstream to the ocean, measuring turbidity at regular intervals. Deployment in the Herbert River showed a downstream increase in turbidity, and thus suspended sediment concentration, while for the Johnstone River there was a rapid reduction in turbidity where the river entered the sea. Potential stranding along river banks is a limitation of the instrument. However, it has proved possible for drifters to routinely collect data along 80 km of the Herbert River. One drifter deployed in the Fly River, Papua New Guinea, travelled almost 200 km before stranding. Copyright © 2014 Elsevier Ltd. All rights reserved.
Toohey, Ryan C; Herman-Mercer, Nicole M.; Schuster, Paul F.; Mutter, Edda A.; Koch, Joshua C.
2016-01-01
The Yukon River Basin, underlain by discontinuous permafrost, has experienced a warming climate over the last century that has altered air temperature, precipitation, and permafrost. We investigated a water chemistry database from 1982 to 2014 for the Yukon River and its major tributary, the Tanana River. Significant increases of Ca, Mg, and Na annual flux were found in both rivers. Additionally, SO4 and P annual flux increased in the Yukon River. No annual trends were observed for dissolved organic carbon (DOC) from 2001 to 2014. In the Yukon River, Mg and SO4 flux increased throughout the year, while some of the most positive trends for Ca, Mg, Na, SO4, and P flux occurred during the fall and winter months. Both rivers exhibited positive monthly DOC flux trends for summer (Yukon River) and winter (Tanana River). These trends suggest increased active layer expansion, weathering, and sulfide oxidation due to permafrost degradation throughout the Yukon River Basin.
Galloway, Joel M.; Blanchard, Robert A.; Ellison, Christopher A.
2011-01-01
Most of the bedload samples had particle sizes in the 0.5 to 1 millimeter and 0.25 to 0.5 millimeter ranges from the Maple River, Wild Rice River, Rush River, Buffalo River, and Red River sites. The Rush and Lower Branch Rush Rivers also had a greater portion of larger particle sizes in the 1 to 2 millimeter range. The Sheyenne River sites had a greater portion of smaller particle sizes in the bedload in the 0.125 to 0.5 millimeter range compared to the other sites. The bed material in samples collected during the 2011 spring high-flow event demonstrated a wider distribution of particle sizes than were observed in the bedload; the coarsest material was found at the Red River near Christine and the Lower Branch Rush River and the finest material at the Sheyenne River sites.
Regional distribution of mercury in sediments of the main rivers of French Guiana (Amazonian basin).
Laperche, Valérie; Hellal, Jennifer; Maury-Brachet, Régine; Joseph, Bernard; Laporte, Pierre; Breeze, Dominique; Blanchard, François
2014-01-01
Use of mercury (Hg) for gold-mining in French Guiana (up until 2006) as well as the presence of naturally high background levels in soils, has led to locally high concentrations in soils and sediments. The present study maps the levels of Hg concentrations in river sediments from five main rivers of French Guiana (Approuague River, Comté River, Mana River, Maroni River and Oyapock River) and their tributaries, covering more than 5 450 km of river with 1 211 sampling points. The maximum geological background Hg concentration, estimated from 241 non-gold-mined streams across French Guiana was 150 ng g(-1). Significant differences were measured between the five main rivers as well as between all gold-mining and pristine areas, giving representative data of the Hg increase due to past gold-mining activities. These results give a unique large scale vision of Hg contamination in river sediments of French Guiana and provide fundamental data on Hg distribution in pristine and gold-mined areas.
Luo, Xiao-Jun; Chen, She-Jun; Mai, Bi-Xian; Zeng, Yong-Ping; Sheng, Guo-Ying; Fu, Jia-Mo
2005-07-01
Polycyclic aromatic hydrocarbons (PAHs) are measured in surface sediments from rivers and estuary of Pearl River Delta and its nearby South China Sea. Total PAH concentration varied from 255.9 - 16 670.3 ng/g and a moderate to low level compare to relevant areas worldwide. The order of PAHs concentration in sediments was: rivers of Pearl River Delta > estuary > South China Sea, and the most significant PAH contamination was at Guangzhou channel of Zhujiang river. A decrease trend for PAHs concentration with distance from estuary to open sea can be sees in South China Sea. Coal and biomass combustion is the major source of PAHs in nearshore of South China Sea, and petroleum combustion is the main source of pyrolytic PAHs in rivers and estuary of Pearl River Delta according to PAHs diagnostic ratios. Petroleum PAHs are revealed have a high contribution to PAHs in Xijiang River, estuary and some stations in Zhujiang River. A comparison of data from study in 1997 with data from present study indicates that there is no clear change in the PAH concentration over time but the source of PAHs in Pearl River Delta have been change from a main coal combustion to petroleum combustion and being reflect in the sediments in rivers and estuary of Pearl River Delta where there have high sedimentation rate.
Wood duck brood movements and habitat use on prairie rivers in South Dakota
Granfors, D.A.; Flake, Lester D.
1999-01-01
Wood duck (Aix sponsa) populations have been increasing in the Central Flyway, but little is known about wood duck brood rearing in prairie ecosystems. We compared movements and habitat use of radiomarked female wood ducks with broods in South Dakota on 2 rivers with contrasting prairie landscapes. The perennial Big Sioux River had a broad floodplain and riparian forest, whereas the intermittent Maple River had emergent vegetation along the river channel. Movements between nest sites and brood-rearing areas were longer on the Maple River than on the Big Sioux River (P = 0.02) and were among the longest reported for wood duck broods. Movements on the Big Sioux River were longer in 1992 (P = 0.01), when the floodplain was dry, than in 1993 or 1994. Before flooding occurred on the Big Sioux River, broods used semipermanent wetlands and tributaries outside the floodplain; thereafter, females selected forested wetlands along the river. Broods on the Maple River used emergent vegetation along the river channel throughout the study. Because median length of travel to brood-rearing areas was 2-3 km we recommend maintenance of brood-rearing habitat every 3-5 km along prairie rivers. Wildlife managers should encourage landowners to retain riparian vegetation along perennial rivers and emergent vegetation along intermittent streams to provide brood-rearing habitat during wet and dry cycles.
NASA Astrophysics Data System (ADS)
Li, Z.; Li, C.
2017-12-01
Connectivity is one of the most important characteristics of a river, which is derived from the natural water cycle and determine the renewability of river water. The water conservancy project can change the connectivity of natural river networks, and directly threaten the health and stability of the river ecosystem. Based on the method of Dendritic Connectivity Index (DCI), the impacts from sluices and dams on the connectivity of river network are deeply discussed herein. DCI quantitatively evaluate the connectivity of river networks based on the number of water conservancy facilities, the connectivity of fish and geographical location. The results show that the number of water conservancy facilities and their location in the river basin have a great influence on the connectivity of the river network. With the increase of the number of sluices and dams, DCI is decreasing gradually, but its decreasing range is becoming smaller and smaller. The dam located in the middle of the river network cuts the upper and lower parts of the whole river network, and destroys the connectivity of the river network more seriously. Therefore, this method can be widely applied to the comparison of different alternatives during planning of river basins and then provide a reference for the site selection and design of the water conservancy project and facility concerned.
Federal Register 2010, 2011, 2012, 2013, 2014
2013-05-15
... to the local maritime community via broadcast notice to mariners. 2. Impact on Small Entities Under...-AA08 Special Local Regulation; Low Country Splash, Wando River, Cooper River, and Charleston Harbor... establishing a special local regulation on the waters of the Wando River, Cooper River, and Charleston Harbor...
77 FR 75917 - Drawbridge Operation Regulation; New Haven Harbor, Quinnipiac and Mill Rivers, CT
Federal Register 2010, 2011, 2012, 2013, 2014
2012-12-26
...-AA09 Drawbridge Operation Regulation; New Haven Harbor, Quinnipiac and Mill Rivers, CT AGENCY: Coast..., mile 1.3, across the Quinnipiac River, and the Chapel Street Bridge, mile 0.4, across the Mill River..., across the Quinnipiac River, and the Chapel Street Bridge, mile 0.4, across the Mill River, to reduce the...
33 CFR 162.205 - Suisun Bay, San Joaquin River, Sacramento River, and connecting waters, CA.
Code of Federal Regulations, 2013 CFR
2013-07-01
..., Sacramento River, and connecting waters, CA. 162.205 Section 162.205 Navigation and Navigable Waters COAST... NAVIGATION REGULATIONS § 162.205 Suisun Bay, San Joaquin River, Sacramento River, and connecting waters, CA. (a) San Joaquin River Deep Water Channel between Suisun Bay and the easterly end of the channel at...
33 CFR 162.205 - Suisun Bay, San Joaquin River, Sacramento River, and connecting waters, CA.
Code of Federal Regulations, 2014 CFR
2014-07-01
..., Sacramento River, and connecting waters, CA. 162.205 Section 162.205 Navigation and Navigable Waters COAST... NAVIGATION REGULATIONS § 162.205 Suisun Bay, San Joaquin River, Sacramento River, and connecting waters, CA. (a) San Joaquin River Deep Water Channel between Suisun Bay and the easterly end of the channel at...
33 CFR 162.205 - Suisun Bay, San Joaquin River, Sacramento River, and connecting waters, CA.
Code of Federal Regulations, 2012 CFR
2012-07-01
..., Sacramento River, and connecting waters, CA. 162.205 Section 162.205 Navigation and Navigable Waters COAST... NAVIGATION REGULATIONS § 162.205 Suisun Bay, San Joaquin River, Sacramento River, and connecting waters, CA. (a) San Joaquin River Deep Water Channel between Suisun Bay and the easterly end of the channel at...
76 FR 22033 - Safety Zone; Red River Safety Zone, Red River, MN
Federal Register 2010, 2011, 2012, 2013, 2014
2011-04-20
...-AAOO Safety Zone; Red River Safety Zone, Red River, MN AGENCY: Coast Guard, DHS. ACTION: Temporary... a temporary safety zone on the Red River, MN. This safety zone is being established to ensure the... Red River in the State of Minnesota north of a line drawn across latitude 46[deg]20'00'' N, including...
Code of Federal Regulations, 2014 CFR
2014-07-01
... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Special Local Regulations; Low Country Splash, Wando River, Cooper River, and Charleston Harbor, Charleston, SC. 100.T07-0110 Section 100... Splash, Wando River, Cooper River, and Charleston Harbor, Charleston, SC. (a) Regulated Areas. The...
76 FR 25545 - Safety Zone; Blue Crab Festival Fireworks Display, Little River, Little River, SC
Federal Register 2010, 2011, 2012, 2013, 2014
2011-05-05
...-AA00 Safety Zone; Blue Crab Festival Fireworks Display, Little River, Little River, SC AGENCY: Coast... zone on the waters of Little River in Little River, South Carolina during the Blue Crab Festival... this rule because the Coast Guard did not receive notice of the Blue Crab Festival Fireworks Display...
3. SNAKE RIVER VALLEY IRRIGATION DISTRICT, PHOTOGRAPHIC COPY OF DRAWING, ...
3. SNAKE RIVER VALLEY IRRIGATION DISTRICT, PHOTOGRAPHIC COPY OF DRAWING, PROFILE AND ALIGNMENT OF DAM ACROSS WEST CHANNEL OF SNAKE RIVER, SHEET 3 OF 5, 1924 (on file at the Idaho State Office of Water Resources, Boise, Idaho) - Snake River Valley Irrigation District, East Side of Snake River (River Mile 796), Shelley, Bingham County, ID
36 CFR 292.45 - Use of motorized and non-motorized rivercraft.
Code of Federal Regulations, 2012 CFR
2012-07-01
... use and enjoyment of the rivers: Provided, that where wild and scenic rivers are concerned, the... except on the Snake River and that portion of the Salmon River in the HCNRA administered by the Forest... for the safe use and enjoyment of the rivers: Provided, that where wild and scenic rivers are involved...
36 CFR 292.45 - Use of motorized and non-motorized rivercraft.
Code of Federal Regulations, 2011 CFR
2011-07-01
... use and enjoyment of the rivers: Provided, that where wild and scenic rivers are concerned, the... except on the Snake River and that portion of the Salmon River in the HCNRA administered by the Forest... for the safe use and enjoyment of the rivers: Provided, that where wild and scenic rivers are involved...
36 CFR 292.45 - Use of motorized and non-motorized rivercraft.
Code of Federal Regulations, 2013 CFR
2013-07-01
... use and enjoyment of the rivers: Provided, that where wild and scenic rivers are concerned, the... except on the Snake River and that portion of the Salmon River in the HCNRA administered by the Forest... for the safe use and enjoyment of the rivers: Provided, that where wild and scenic rivers are involved...
36 CFR 292.45 - Use of motorized and non-motorized rivercraft.
Code of Federal Regulations, 2014 CFR
2014-07-01
... use and enjoyment of the rivers: Provided, that where wild and scenic rivers are concerned, the... except on the Snake River and that portion of the Salmon River in the HCNRA administered by the Forest... for the safe use and enjoyment of the rivers: Provided, that where wild and scenic rivers are involved...
ZumBerge, Jeremy Ryan; Lee, Kathy E.; Goldstein, Robert M.
2003-01-01
Biological communities in the Mississippi River reflected changes in water quality and physical habitat as the Minnesota and St. Croix Rivers join the Mississippi River. Periphyton density and biovolume, and the relative abundance of blue-green algae density increased in the Mississippi River at the confluence compared to the Minnesota and St. Croix Rivers. Relative abundance of benthic invertebrate taxa richness and diversity generally decreased downstream in the large rivers as urban and agricultural land use become more prevalent. Impoundments and dredging of the Mississippi River in and downstream from the TCMA exacerbate effects of increasing river size to produce a more lake-like system.
The influence of the macro-sediment from the mountainous area to the river morphology in Taiwan
NASA Astrophysics Data System (ADS)
Chen, S. C.; Wu, C.; Shih, P.
2012-12-01
Chen, Su-Chin scchen@nchu.edu.tw Wu, Chun-Hung* chwu@mail.nchu.edu.tw Dept. Soil & Water Conservation, National Chung Hsing University, Taichung, Taiwan. The Chenyulan River was varied changed with the marco-sediment yielded source area, Shenmu watershed, with 10 debris flow events in the last decade, in Central Taiwan. Multi-term DEMs, the measurement data of the river topographic profile and aerial photos are adopted to analyze the decade influences of the marco-sediment to the river morphology in Chenyulan River. The changes of river morphology by observing the river pattern, calculating the multi-term braided index, and estimating the distribution of sediment deposition and main channel in the river. The response for the macro-sediment from the mountainous areas into the river in the primary stage is the increase in river width, the depth of sediment deposition and volume of sediment transport. The distribution of sediment deposition from upstream landslide and river bank erosion along the river dominates the change of river morphology in the primary stage. The river morphology achieves stable gradually as the river discharge gradually decreases in the later stage. Both of the braided index and the volume of sediment transport decrease, and the river flow maintains in a main channel instead of the braided pattern in this stage. The decade sediment deposition depth is estimated as > 0.5 m, especially > 3.5 m in the sections closed to the sediment-yield source areas, the mean river width increases 15%, and the sediment with a total volume of 8×107 tons has been transported in last decade in Chenyulan River. The river morphology in Chenyulan River maintains a short-term stable, i.e. 2 or 3 years, and changes again because of the flooding events with a large amount of sediment caused by frequently heavy rainfall events in Taiwan. Furthermore, the response of river morphology in Chenyulan River due to the heavy rainfall with a total precipitation of around 860 mm in 3 days in 2009 Typhoon Morakot is also discussed in the study. A extreme river discharge with the return period of 100 year transported the macro sediment with the total volume of around 3.2×107 m3 in 8 days during 2009 Typhoon Morakot, and it also resulted in 18.1% increase of the mean river width and 4 m increase of the mean scouring depth in Chenyulan River, especially the mean increase of 50 m in river width resulted from the total sediment volume of 1.9×107 m3 deposited within 8 km from the sediment-yielded area, i.e. Shenmu watershed. Furthermore, the distribution of sediment deposition in a narrow pass is also discussed in the research. Sediment deposited apparently in the upstream of a narrow pass and also results in the disordered river patterns. The high velocity flow due to the contraction of the river width in the narrow pass section also leads to the headwater erosion in the upstream of the narrow pass section. Contrarily, the unapparent sediment deposition in the downstream of the narrow pass section brings about the stable main channel and swinging flow patterns from our decade observation.
NASA Astrophysics Data System (ADS)
Habets, F.; Vergnes, J.
2013-12-01
The Upper Rhine alluvial aquifer is an important transboundary water resource which is particularly vulnerable to pollution from the rivers due to anthropogenic activities. A realistic simulation of the groundwater-river exchanges is therefore of crucial importance for effective management of water resources, and hence is the main topic of the NAPROM project financed by the French Ministry of Ecology. Characterization of these fluxes in term of quantity and spatio-temporal variability depends on the choice made to represent the river water stage in the model. Recently, a couple surface-subsurface model has been applied to the whole aquifer basin. The river stage was first chosen to be constant over the major part of the basin for the computation of the groundwater-river interactions. The present study aims to introduce a variable river water stage to better simulate these interactions and to quantify the impact of this process over the simulated hydrological variables. The general modeling strategy is based on the Eau-Dyssée modeling platform which couples existing specialized models to address water resources and quality in regional scale river basins. In this study, Eau-Dyssée includes the RAPID river routing model and the SAM hydrogeological model. The input data consist in runoff and infiltration coming from a simulation of the ISBA land surface scheme covering the 1986-2003 period. The QtoZ module allows to calculate river stage from simulated river discharges, which is then used to calculate the exchanges between aquifer units and river. Two approaches are compared. The first one uses rating curves derived from observed river discharges and river stages. The second one is based on the Manning's formula. Manning's parameters are defined with geomorphological parametrizations and topographic data based on Digital Elevation Model (DEM). First results show a relatively good agreement between observed and simulated river water height. Taking into account a variable river stage seems to increase the amount of water exchanged between groundwater and river. Systematic biases are nevertheless found between simulated and observed mean river stage elevation. They show that the primary source of errors when simulating river stage - and hence groundwater-river interactions - is the uncertainties associated with the topographic data used to define the riverbed elevation. Thus, this study confirms the need to access to more accurate DEM for estimating riverbed elevation and studying groundwater-river interactions, at least at regional scale.
Owen-Joyce, Sandra J.; Wilson, Richard P.
1994-01-01
In the Colorado River valley between the east end of Lake Mead and the international boundary with Mexico (see figure), the river is the principal source of water for agricultural, domestic, municipal, industrial, hydroelectric-power generation, and recreational purposes. Water is stored in surface reservoirs and in the river aquifer---permeable sediments and sedimentary rocks that fill the lower Colorado River valley and adjacent tributary valleys. The hydraulic connection between the river and the river aquifer, overbank flow prior to building of the dams, and infiltration as the reservoirs filled allowed the sediments and sedimentary rocks to become saturated with water from the river. Ratios of isotopes of hydrogen and oxygen in water from wells indicate that most of the water in the river aquifer beneath the flood plain and in many places beneath the adjacent alluvial slopes originated from the river. The water table in the river aquifer extends from the river, beneath the flood plain, and under the alluvial slopes until it intersects bedrock. Precipitation in the surrounding mountains and inflow from tributary valleys also contribute small quantities of water to the river aquifer. Consumptive use of river water in the valley results from evapotranspiration by vegetation (crops and phreatophytes) on the flood plain, pumpage from wells to meet domestic and municipal needs, and pumpage from the river for export to areas in California, Arizona, and Nevada outside of the river valley. Most crops are grown on the flood plain; in a few areas, land on the adjacent terraces has been cultivated. Crops were grown on about 70 percent of the total vegetated area in 1984. Phreatophytes---natural vegetation that obtains water from the river aquifer---covered the remaining vegetated areas on the uncultivated flood plain. Most of the water used for irrigation is diverted or pumped directly from the river and reservoirs. Most of the water used for domestic and municipal purposes is pumped from wells on the flood plain, on adjacent alluvial slopes, and in tributary valleys. River water also is delivered to Mexico in accordance with an international treaty.
Effect of human activities on overall trend of sedimentation in the lower Yellow River, China.
Jiongxin, Xu
2004-05-01
The Yellow River has been intensively affected by human activities, particularly in the past 50 years, including soil-water conservation in the upper and middle drainage basin, flood protection in the lower reaches, and flow regulation and water diversion in the whole drainage basin. All these changes may impact sedimentation process of the lower Yellow River in different ways. Assessing these impacts comprehensively is important for more effective environmental management of the drainage basin. Based on the data of annual river flow, sediment load, and channel sedimentation in the lower Yellow River between 1950 and 1997, the purpose of this paper is to analyze the overall trend of channel sedimentation rate at a time scale of 50 years, and its formative cause. It was found in this study that erosion control measures and water diversion have counteractive impacts on sedimentation rate in the lower Yellow River. Although both annual river flow and sediment decreased, there was no change in channel sedimentation rate. A regression analysis indicated that the sedimentation in the lower Yellow River decreased with the sediment input to the lower Yellow River but increased with the river flow input. In the past 30-40 years, the basin-wide practice of erosion and sediment control measures resulted in a decline in sediment supply to the Yellow River; at the same time, the human development of water resources that required river flow regulation and water diversion caused great reduction in river flow. The former may reduce the sedimentation in the lower Yellow River, but the reduction of river flow increased the sedimentation. When their effects counterbalanced each other, the overall trend of channel sedimentation in the lower Yellow River remained unchanged. This fact may help us to better understand the positive and negative effects of human activities in the Yellow River basin and to pay more attention to the negative effect of the development of water resources. The results of this study demonstrate that, if the overuse of river water cannot be controlled, the reduction of channel sedimentation in the lower Yellow River cannot be realized through the practice of erosion and sediment control measures.
NASA Astrophysics Data System (ADS)
Harvey, J. W.; Gomez-Velez, J. D.; Scott, D.; Boyer, E. W.; Schmadel, N. M.; Alexander, R. B.; Eng, K.; Golden, H. E.; Kettner, A.; Konrad, C. P.; Moore, R. B.; Pizzuto, J. E.; Schwarz, G. E.; Soulsby, C.
2017-12-01
The functional values of rivers depend on more than just wetted river channels. Instead, the river channel exchanges water and suspended materials with adjacent riparian, floodplain, hyporheic zones, and ponded waters such as lakes and reservoirs. Together these features comprise a larger functional unit known as the river corridor. The exchange of water, solutes, and sediments within the river corridor alters downstream water quality and ecological functions, but our understanding of the large-scale, cumulative impacts is inadequate and has limited advancements in sustainable management practices. A problem with traditional watershed, groundwater, and river water quality models is that none of them explicitly accounts for river corridor storage and processing, and the exchanges of water, solutes, and sediments that occur many times between the channel and off-channel environments during a river's transport to the sea. Our River Corridor Working Group at the John Wesley Powell Center is quantifying the key components of river corridor functions. Relying on foundational studies that identified floodplain, riparian, and hyporheic exchange flows and resulting enhancement of chemical reactions at river reach scales, we are assembling the datasets and building the models to upscale that understanding onto 2.6 million river reaches in the U.S. A principal goal of the River Corridor Working group is to develop a national-scale river corridor model for the conterminous U.S. that will reveal, perhaps for the first time, the relative influences of hyporheic, riparian, floodplain, and ponded waters at large spatial scales. The simple but physically-based models are predictive for changing conditions and therefore can directly address the consequences and effectiveness of management actions in sustaining valuable river corridor functions. This presentation features interpretation of useful river corridor connectivity metrics and ponded water influences on nutrient and sediment processing in river networks of the Mid-Atlantic and Northeastern U.S. This research is a product of the John Wesley Powell Center River Corridor Working Group https://powellcenter.usgs.gov/view-project
Kratzer, Charles R.; Zamora, Celia; Knifong, Donna L.
2002-01-01
The application of diazinon and chlorpyrifos on dormant orchards in 2000 in the San Joaquin River Basin was less than 21 percent of application in 1993 and 1994. A total of 13 sites were sampled weekly during nonstorm periods and more frequently during two storm periods. The sites included five major river and eight minor tributary sites. The highest concentrations of diazinon and chlorpyrifos occurred during the storm periods. Four samples from major river sites (Tuolumne River and two San Joaquin River sites) had diazinon concentrations greater than 0.08 microgram per liter, the concentration being considered by the state of California as its criterion maximum concentration for the protection of aquatic habitat. One sample from a major river site (San Joaquin River) exceeded the equivalent State guideline of 0.02 microgram per liter for chlorpyrifos. At the eight minor tributary sites, 24 samples exceeded the diazinon guideline and four samples exceeded the chlorpyrifos guideline. The total diazinon load in the San Joaquin River near Vernalis during January and February 2000 was 19.6 pounds active ingredient; of this, 8.17 pounds active ingredient was transported during two storms. In 1994, 27.4 pounds active ingredient was transported during two storms. The total chlorpyrifos load in the San Joaquin River near Vernalis during January and February 2000 was 5.68 pounds active ingredient; of this, 2.17 pounds active ingredient was transported during the two storms. During the frequently sampled February 2000 storm, the main sources of diazinon in the San Joaquin River Basin were the San Joaquin River near Stevinson Basin (25 percent), Tuolumne River Basin (14 percent), and the Stanislaus River Basin (10 percent). The main sources of chlorpyrifos in the San Joaquin River Basin were the San Joaquin River near Stevinson Basin (17 percent), Tuolumne River Basin (13 percent), and the Merced River Basin (11 percent). The total January and February diazinon load in the San Joaquin River near Vernalis was 0.17 percent of dormant application; total January and February chlorpyrifos load was 0.16 percent of dormant application.
Đorđievski, Stefan; Ishiyama, Daizo; Ogawa, Yasumasa; Stevanović, Zoran
2018-06-22
Bor, Krivelj, and Bela Rivers belong to the watershed of Timok River, which is a tributary of transboundary Danube River. These rivers receive metal-rich acidic wastewater from metallurgical facilities and acid mine drainage (AMD) from mine wastes around Bor copper mines. The aim of this study was to determine the mobility and natural attenuation of metals and arsenic in rivers from Bor copper mines to Danube River during the year 2015. The results showed that metallurgical facilities had the largest impact on Bor River by discharging about 400 t of Cu per year through highly acidic wastewater (pH = 2.6). The highest measured concentrations of Cu in river water and sediments were 40 mg L -1 and 1.6%, respectively. Dissolution of calcite from limestone bedrock and a high concentration of bicarbonate ions in natural river water (about 250 mg L -1 ) enhanced the neutralization of acidic river water and subsequent chemical precipitation of metals and arsenic. Decreases in the concentrations of Al, Fe, Cu, As, and Pb in river water were mainly due to precipitation on the river bed. On the other hand, dilution played an important role in the decreases in concentrations of Mn, Ni, Zn, and Cd. Chemically precipitated materials and flotation tailings containing Fe-rich minerals (fayalite, magnetite, and pyrite) were transported toward Danube River during the periods of high discharge. This study showed that processes of natural attenuation in catchments with limestone bedrock play an important role in reducing concentrations of metals and arsenic in AMD-bearing river water.
Climatic control of bedrock river incision.
Ferrier, Ken L; Huppert, Kimberly L; Perron, J Taylor
2013-04-11
Bedrock river incision drives the development of much of Earth's surface topography, and thereby shapes the structure of mountain belts and modulates Earth's habitability through its effects on soil erosion, nutrient fluxes and global climate. Although it has long been expected that river incision rates should depend strongly on precipitation rates, quantifying the effects of precipitation rates on bedrock river incision rates has proved difficult, partly because river incision rates are difficult to measure and partly because non-climatic factors can obscure climatic effects at sites where river incision rates have been measured. Here we present measurements of river incision rates across one of Earth's steepest rainfall gradients, which show that precipitation rates do indeed influence long-term bedrock river incision rates. We apply a widely used empirical law for bedrock river incision to a series of rivers on the Hawaiian island of Kaua'i, where mean annual precipitation ranges from 0.5 metres to 9.5 metres (ref. 12)-over 70 per cent of the global range-and river incision rates averaged over millions of years can be inferred from the depth of river canyons and the age of the volcanic bedrock. Both a time-averaged analysis and numerical modelling of transient river incision reveal that the long-term efficiency of bedrock river incision across Kaua'i is positively correlated with upstream-averaged mean annual precipitation rates. We provide theoretical context for this result by demonstrating that our measurements are consistent with a linear dependence of river incision rates on stream power, the rate of energy expenditure by the flow on the riverbed. These observations provide rare empirical evidence for the long-proposed coupling between climate and river incision, suggesting that previously proposed feedbacks among topography, climate and tectonics may occur.
How Do Morphodynamic Signatures Vary Along the Ucayali, a Large Transitional River?
NASA Astrophysics Data System (ADS)
Dauer, K.; Frias, C. E.; Abad, J. D.; Paredes, J.; Vizcarra, J.; Holguin, C.
2013-12-01
The Ucayali River, with an average discharge of 11, 260 m3 ● s-1 at the Requena station, is one of the largest rivers in Peru, and at its confluence with the Maranon River, the Amazon River is born. The Ucayali River transitions from purely meandering to quasi-anabranching planform near the confluence with the Marañon River. In addition, it carries large amounts of suspended sediment and has been shown to display high rates of migration. Prompted by evidence of changing trends in rainfall and discharge in the Amazon basin, where the Ucayali is located, we have performed a baseline characterization of the planform metrics, thus to determine if effects of climatic change on the morphodynamics are happening in this transitional river, which is a vital transportation route for cities in the jungle such as Iquitos, Peru. Herein, the morphodynamics of the Ucayali River are characterized from its upstream end in Atalaya, Peru to its confluence with the Marañon near Nauta City. First, the migration rates along the Ucayali River are calculated from temporal Landsat images. Then migration rates and planform characteristics, such as wavelength and sinuosity, along the river are compared with the slope along the river to distinguish spatial dominant scales. In addition, bathymetry and velocity measurements taken in 2013 along the Ucayali River help us to understand the complex morphodynamics of the river. Specific case studies have been done at Pucallpa and Jenaro-Herrera, Peru using hydrodynamic and bathymetric measurements complemented with high-resolution shallow water modeling to understand the process of cutoff formation in different locations along the river. This study discusses the frequency at which meanders along the Ucayali River shift from low sinuosity to complete maturity in order to produce cutoffs.
Reach-scale characterization of large woody debris in a low-gradient, Midwestern U.S.A. river system
NASA Astrophysics Data System (ADS)
Martin, Derek J.; Pavlowsky, Robert T.; Harden, Carol P.
2016-06-01
Addition of large woody debris (LWD) to rivers has increasingly become a popular stream restoration strategy, particularly in river systems of the Midwestern United States. However, our knowledge of LWD dynamics is mostly limited to high gradient montane river systems, or coastal river systems. The LWD-related management of low-gradient, Midwestern river systems is thus largely based on higher gradient analogs of LWD dynamics. This research characterizes fluvial wood loads and investigates the relationships between fluvial wood, channel morphology, and sediment deposition in a relatively low-gradient, semiconfined, alluvial river. The LWD and channel morphology were surveyed at nine reaches along the Big River in southeastern Missouri to investigate those relationships in comparison to other regions. Wood loads in the Big River are low (3-114 m3/100 m) relative to those of higher gradient river systems of the Pacific Northwest, but high relative to lower-gradient river systems of the Eastern United States. Wood characteristics such as size and orientation suggest that the dominant LWD recruitment mechanism in the Big River is bank erosion. Also, ratios of wood geometry to channel geometry show that the Big River maintains a relatively high wood transport capacity for most of its length. Although LWD creates sites for sediment storage, the overall impact on reach-scale sediment storage in the Big River is low (< 4.2% of total in-channel storage). However, wood loads, and thus opportunities for sediment storage, have the potential to grow in the future as Midwestern riparian forests mature. This study represents the first of its kind within this particular type of river system and within this region and thus serves as a basis for understanding fluvial wood dynamics in low-gradient river systems of the Midwestern United States.
My River My Home: Both Art and Science
NASA Astrophysics Data System (ADS)
Gillies, S. L.; Janmaat, A.; Marsh, S. J.; Peucker-Ehrenbrink, B.; Voss, B.; Holmes, R. M.; King, S.; Bertrand, K.
2014-12-01
The University of the Fraser Valley has been researching the water chemistry of the Fraser River since 2009 as a member of the Global Rivers Observatory coordinated by Woods Hole Oceanographic Institution and Woods Hole Research Center. The Global Rivers Observatory is advancing our understanding of how climate change, deforestation, and other disturbances are impacting river chemistry and land-ocean linkages. This knowledge is vital for tracking the health of Earth's watersheds and predicting how Earth's water and chemical cycles will change in the future. The Global Rivers Observatory also promotes the communication of science to the general public. In September 2013, the My River My Home art and science exhibit opened at the Fraser River Discovery Centre, New Westminster, BC. The exhibit is a global exchange of artwork created by children living along the rivers being studied by the Global Rivers Observatory scientists. The exhibit is intended to inspire young students to develop an awareness of the environment and the importance of rivers. Scientists from UFV, WHOI, and WHRC worked together with the Fraser River Discovery Centre on the science communication aspects of the display and to develop hands-on science activities looking at different aspects of river water quality. The exhibition has led to the creation of My River My Home, An Activity Kit for Educators about the sustainability of the Fraser River. The kit is being offered through the Fraser River Discovery Centre and deals with issues such as the importance of water, water quality, and encouraging a global perspective. The resource kit was classroom tested by several teachers, and four UBC teacher candidates worked on incorporating teacher suggestions into the kit. The resource kit will be available on-line at the end of September 2014 and contains inquiry based activities suitable for a variety of educational levels.
Environmental and hydrologic overview of the Yukon River basin, Alaska and Canada
Brabets, Timothy P.; Wang, Bronwen; Meade, Robert H.
2000-01-01
The Yukon River, located in northwestern Canada and central Alaska, drains an area of more than 330,000 square miles, making it the fourth largest drainage basin in North America. Approximately 126,000 people live in this basin and 10 percent of these people maintain a subsistence lifestyle, depending on the basin's fish and game resources. Twenty ecoregions compose the Yukon River Basin, which indicates the large diversity of natural features of the watershed, such as climate, soils, permafrost, and geology. Although the annual mean discharge of the Yukon River near its mouth is more than 200,000 cubic feet per second, most of the flow occurs in the summer months from snowmelt, rainfall, and glacial melt. Eight major rivers flow into the Yukon River. Two of these rivers, the Tanana River and the White River, are glacier-fed rivers and together account for 29 percent of the total water flow of the Yukon. Two others, the Porcupine River and the Koyukuk River, are underlain by continuous permafrost and drain larger areas than the Tanana and the White, but together contribute only 22 percent of the total water flow in the Yukon. At its mouth, the Yukon River transports about 60 million tons of suspended sediment annually into the Bering Sea. However, an estimated 20 million tons annually is deposited on flood plains and in braided reaches of the river. The waters of the main stem of the Yukon River and its tributaries are predominantly calcium magnesium bicarbonate waters with specific conductances generally less than 400 microsiemens per centimeter. Water quality of the Yukon River Basin varies temporally between summer and winter. Water quality also varies spatially among ecoregions
Zheng, Na; Wang, Qichao; Liang, Zhongzhu; Zheng, Dongmei
2008-07-01
Wuli River, Cishan River, and Lianshan River are three freshwater rivers flowing through Huludao City, in a region of northeast China strongly affected by industrialization. Contamination assessment has never been conducted in a comprehensive way. For the first time, the contamination of three rivers impacted by different sources in the same city was compared. This work investigated the distribution and sources of Hg, Pb, Cd, Zn and Cu in the surface sediments of Wuli River, Cishan River, and Lianshan River, and assessed heavy metal toxicity risk with the application of two different sets of Sediment Quality Guideline (SQG) indices (effect range low/effect range median values, ERL/ERM; and threshold effect level/probable effect level, TEL/PEL). Furthermore, this study used a toxic unit approach to compare and gauge the individual and combined metal contamination for Hg, Pb, Cd, Zn and Cu. Results showed that Hg contamination in the sediments of Wuli River originated from previous sediment contamination of the chlor-alkali producing industry, and Pb, Cd, Zn and Cu contamination was mainly derived from atmospheric deposition and unknown small pollution sources. Heavy metal contamination to Cishan River sediments was mainly derived from Huludao Zinc Plant, while atmospheric deposition, sewage wastewater and unknown small pollution were the primary sources for Lianshan River. The potential acute toxicity in sediment of Wuli River may be primarily due to Hg contamination. Hg is the major toxicity contributor, accounting for 53.3-93.2%, 7.9-54.9% to total toxicity in Wuli River and Lianshan River, respectively, followed by Cd. In Cishan River, Cd is the major sediment toxicity contributor, however, accounting for 63.2-66.9% of total toxicity.
Numerical Simulation of Missouri River Bed Evolution Downstream of Gavins Point Dam
NASA Astrophysics Data System (ADS)
Sulaiman, Z. A.; Blum, M. D.; Lephart, G.; Viparelli, E.
2016-12-01
The Missouri River originates in the Rocky Mountains in western Montana and joins the Mississippi River near Saint Louis, Missouri. In the 1900s dam construction and river engineering works, such as river alignment, narrowing and bank protections were performed in the Missouri River basin to control the flood flows, ensure navigation and use the water for agricultural, industrial and municipal needs, for the production of hydroelectric power generation and for recreation. These projects altered the flow and the sediment transport regimes in the river and the exchange of sediment between the river and the adjoining floodplain. Here we focus on the long term effect of dam construction and channel narrowing on the 1200 km long reach of the Missouri River between Gavins Point Dam, Nebraska and South Dakota, and the confluence with the Mississippi River. Field observations show that two downstream migrating waves of channel bed degradation formed in this reach in response to the changes in flow regime, sediment load and channel geometry. We implemented a one dimensional morphodynamic model for large, low slope sand bed rivers, we validated the model at field scale by comparing the numerical results with the available field data and we use the model to 1) predict the magnitude and the migration rate of the waves of degradation at engineering time scales ( 150 years into the future), 2) quantify the changes in the sand load delivered to the Mississippi River, where field observations at Thebes, i.e. downstream of Saint Louis, suggest a decline in the mean annual sand load in the past 50 years, and 3) identify the role of the main tributaries - Little Sioux River, Platte River and Kansas River - on the wave migration speed and the annual sand load in the Missouri River main channel.
The science and practice of river restoration
NASA Astrophysics Data System (ADS)
Wohl, Ellen; Lane, Stuart N.; Wilcox, Andrew C.
2015-08-01
River restoration is one of the most prominent areas of applied water-resources science. From an initial focus on enhancing fish habitat or river appearance, primarily through structural modification of channel form, restoration has expanded to incorporate a wide variety of management activities designed to enhance river process and form. Restoration is conducted on headwater streams, large lowland rivers, and entire river networks in urban, agricultural, and less intensively human-altered environments. We critically examine how contemporary practitioners approach river restoration and challenges for implementing restoration, which include clearly identified objectives, holistic understanding of rivers as ecosystems, and the role of restoration as a social process. We also examine challenges for scientific understanding in river restoration. These include: how physical complexity supports biogeochemical function, stream metabolism, and stream ecosystem productivity; characterizing response curves of different river components; understanding sediment dynamics; and increasing appreciation of the importance of incorporating climate change considerations and resiliency into restoration planning. Finally, we examine changes in river restoration within the past decade, such as increasing use of stream mitigation banking; development of new tools and technologies; different types of process-based restoration; growing recognition of the importance of biological-physical feedbacks in rivers; increasing expectations of water quality improvements from restoration; and more effective communication between practitioners and river scientists.
Breck, S.W.; Wilson, K.R.; Andersen, D.C.
2001-01-01
We assessed the effects of flow regulation on the demography of beavers (Castor canadensis) by comparing the density, home-range size, and body size of bank-dwelling beavers on two sixth-order alluvial river systems, the flow-regulated Green River and the free-flowing Yampa River, from 1997 to 2000. Flow regulation on the Green River has altered fluvial geomorphic processes, influencing the availability of willow and cottonwood, which, in turn, has influenced the demography of beavers. Beaver density was higher on the Green River (0.50.6 colonies per kilometre of river) than on the Yampa River (0.35 colonies per kilometre of river). Adult and subadult beavers on the Green River were in better condition, as indicated by larger body mass and tail size. There was no detectable difference in home-range size, though there were areas on the Yampa River that no beavers used. We attribute the improved habitat quality on the Green River to a greater availability of willow. We suggest that the sandy flats and sandbars that form during base flows and the ice cover that forms over winter on the Yampa River increase the energy expended by the beavers to obtain food and increase predation risk and thus lowers the availability of woody forage.
Sacramento River Water Treatment Plant Intake Pier & Access Bridge, ...
Sacramento River Water Treatment Plant Intake Pier & Access Bridge, Spanning Sacramento River approximately 175 feet west of eastern levee on river; roughly .5 mile downstream from confluence of Sacramento & American Rivers, Sacramento, Sacramento County, CA
A fish survey of the White River, Nevada
Scoppettone, G. Gary; Rissler, Peter H.; Shea, Sean
2004-01-01
In spring and summer 1991 and 1992, we surveyed fishes of the White River system, Nye and White Pine Counties, Nevada, to determine the status of natives. There are 5 known native fishes to the White River: Lepidomeda albivallis (White River spinedace), Crenichthys baileyi albivallis (Preston White River springfish), Crenichthys baileyi thermophilus (Moorman White River springfish), Catostomus clarki intermedius (White River desert sucker), and Rhinichthys osculus ssp. (White River speckled dace). All 5 had declined in range. Lepidomeda albivallis had experienced the greatest decline, with less than 50 remaining, and these were restricted to a 70-m stream reach. Rhinichthys osculus spp. was most widespread, found in 18 spring systems. Cottus bairdi (mottled sculpin) was collected for the 1st time from the White River system, where it was probably native. Protective measures should be implemented to conserve all native White River fishes to include C. bairdi.
Toxicity of water from three South Carolina rivers to larval striped bass
Finger, Susan E.; Bulak, James S.
1988-01-01
The toxicity of water from three rivers in the Santee-Cooper drainage of South Carolina was evaluated in a series of on-site studies with larval striped bass Morone saxatilis. Mortality and swimming behavior were assessed daily for larvae exposed to serial dilutions of water collected from the Santee, Congaree, and Wateree rivers. After 96 h, cumulative mortality was 90% in the Wateree River, and a dose–response pattern was evident in serial dilutions of the water. Larvae exposed to water from the Santee and Congaree rivers swam lethargically, but no appreciable mortality was observed. Acutely toxic concentrations of inorganic contaminants were not detected in the rivers; however, pentachloroanisole, a methylated by-product of pentachlorophenol, was twice as high in the Wateree River as it was in the other two rivers. Phenolic compounds may have contributed to larval mortality in the Wateree River and to lethargic activity of larvae in the Santee and Congaree rivers.
Impact of urbanization on the ecology of Mukuvisi River, Harare, Zimbabwe
NASA Astrophysics Data System (ADS)
Moyo, N. A. G.; Rapatsa, M. M.
2016-04-01
The main objective in this study was to compare the physico-chemical characteristics and biota of a river (Mukuvisi) passing through an urban area to that of a non-urbanised river (Gwebi). Five sites in the Mukuvisi River and five sites in the Gwebi River were sampled for water physico-chemical parameters (pH, conductivity, DO, BOD, TDS, ammonia, Cl, SO42-, PO42-, NO33-, F-, Pb, Cu, Fe, Mn, Zn and Cr) once every month between August, 2012-August, 2013. Cluster analysis based on the physico-chemical parameters grouped the sites into two groups. Mukuvisi River sites formed their own grouping except for one site which was grouped with Gwebi River sites. Principal Component Analysis (PCA) was used to extract the physico-chemical parameters that account for most variations in water quality in the Mukuvisi and Gwebi Rivers. PCA identified sulphate, chloride, fluoride, iron, manganese and zinc as the major factors contributing to the variability of Mukuvisi River water quality. In the Gwebi river, sulphate, nitrate, fluoride and copper accounted for most of the variation in water quality. Canonical Correspondence Analysis (CCA) was used to explore the relationship between physico-chemical parameters and macroinvertebrate communities. CCA plots in both Mukuvisi and Gwebi Rivers showed significant relationships between macroinvertebrate communities and water quality variables. Phosphate, ammonia and nitrates were correlated with Chironomidae and Simulidae. Gwebi River had higher (P < 0.05, ANOVA) macroinvertebrates and fish diversity than Mukuvisi River. Clarias gariepinus from the Mukuvisi River had high liver histological lesions and low AChE activity and this led to lower growth rates in this river.
Mastin, M.C.; Fosness, R.L.
2009-01-01
Yakima County is collaborating with the Bureau of Reclamation on a study of the hydraulics and sediment-transport in the lower Naches River and in the Yakima River between Union Gap and Selah Gap in Washington. River bathymetry and topographic data of the river channels are needed for the study to construct hydraulic models. River survey data were available for most of the study area, but river bathymetry and near-river topography were not available for Selah Gap, near the confluence of the Naches and Yakima Rivers, and for Union Gap. In August 2008, the U.S. Geological Survey surveyed the areas where data were not available. If possible, the surveys were made with a boat-mounted, single-beam echo sounder attached to a survey-grade Real-Time Kinematic (RTK) global positioning system (GPS). An RTK GPS rover was used on a walking survey of the river banks, shallow river areas, and river bed areas that were impenetrable to the echo sounder because of high densities of macrophytes. After the data were edited, 95,654 bathymetric points from the boat survey with the echo sounder and 1,069 points from the walking survey with the GPS rover were used in the study. The points covered 4.6 kilometers on the Yakima River and 0.6 kilometers on the Naches River. GPS-surveyed points checked within 0.014 to 0.047 meters in the horizontal direction and -0.036 to 0.078 meters in the vertical direction compared to previously established survey control points
Life history and ecological characteristics of the Santa Ana sucker, Catostomus santaanae
Saiki, Michael K.; Martin, Barbara A.; Knowles, Glen W.; Tennant, Patrick W.
2007-01-01
This study was conducted to document the life history and ecological characteristics of the Santa Ana sucker, Catostomus santaanae, within its native range in southern California. Electrofishing surveys were conducted at 3-month intervals from December 1998 to December 1999 at one site on the San Gabriel River and two sites on the Santa Ana River. Suckers were captured in the San Gabriel River (average, 6.6 fish/10-minutes electrofishing) and at an upstream Santa Ana River site (average, 2.3 fish/10-minutes electrofishing) but not at a downstream Santa Ana River site. Length frequency distributions indicated that at least three year classes (modal groups) of suckers were present in the San Gabriel River, whereas one or two year classes were present in the Santa Ana River. Collection of 21-30 mm standard length (SL) juveniles in June in the Santa Ana River and in September in the San Gabriel River indicated that reproduction occurred over several months. In December, Age-0 suckers averaged 36-48 mm SL in the San Gabriel River and 63-65 mm SL in the Santa Ana River, whereas Age-1 suckers averaged 86 mm SL in the San Gabriel River and 115 mm SL in the Santa Ana River. On average, suckers were in better body condition in the San Gabriel River than in the Santa Ana River. Highest abundance of suckers was associated with relativelypristine environmental conditions (especially low specific conductance) where other native fishes were also common or abundant.
78 FR 46258 - Safety Zone; Upper Mississippi River, Mile 662.8 to 663.9
Federal Register 2010, 2011, 2012, 2013, 2014
2013-07-31
...-AA00 Safety Zone; Upper Mississippi River, Mile 662.8 to 663.9 AGENCY: Coast Guard, DHS. ACTION... Upper Mississippi River, from mile 662.8 to 663.9, extending the entire width of the river. This safety... mile 662.8 to 663.9 on the Upper Mississippi River. Anticipated traffic on the river presents safety...
Federal Register 2010, 2011, 2012, 2013, 2014
2010-09-09
... Regulations; Cape Fear River and Northeast Cape Fear River, in Wilmington, NC AGENCY: Coast Guard, DHS. ACTION..., mile 26.8, and the Isabel S. Holmes Bridge, across Northeast Cape Fear River, mile 1.0, both in... Isabel S. Holmes Bridge, across Northeast Cape Fear River, mile 1.0, a bascule lift bridge, has a...
Federal Register 2010, 2011, 2012, 2013, 2014
2011-07-06
... Operation Regulation; Cape Fear River, and Northeast Cape Fear River, in Wilmington, NC AGENCY: Coast Guard... Northeast Cape Fear River, at mile 1.0, both in Wilmington, NC. The deviation restricts the operation of the... across Northeast Cape Fear River, at mile 1.0, both in Wilmington, NC, requested a temporary deviation...
Code of Federal Regulations, 2010 CFR
2010-10-01
... Habitat for Snake River Sockeye Salmon and Snake River Spring/Summer and Fall Chinook Salmon 3 Table 3 to... Part 226—Hydrologic Units Containing Critical Habitat for Snake River Sockeye Salmon and Snake River Spring/Summer and Fall Chinook Salmon Hydrologic unit name Hydrologic unit number Sockeye salmon Spring...
Code of Federal Regulations, 2011 CFR
2011-10-01
... Habitat for Snake River Sockeye Salmon and Snake River Spring/Summer and Fall Chinook Salmon 3 Table 3 to... Part 226—Hydrologic Units Containing Critical Habitat for Snake River Sockeye Salmon and Snake River Spring/Summer and Fall Chinook Salmon Hydrologic unit name Hydrologic unit number Sockeye salmon Spring...
Limnological aspects of the St. Clair River
Griffiths, Ronald W.; Thornley, Stewart; Edsall, Thomas A.
1991-01-01
To better characterize neoplasm epizootics in the Great Lakes basin and their association with families of contaminants, we sampled five locations: the Fox and Menominee rivers, Lake Michigan; Munuscong Lake, St. Mary's River; and the Black and Cuyahoga rivers, Lake Erie. Frequencies of external and liver tumors were determined for brown bullhead (Ictalurus nebulosus) from all locations except the Black River and for walleye (Stizostedion vitreum) from the Lake Michigan and St. Mary's River sites. Sediment samples were analyzed for metals, polychlorinated aromatics, and polynuclear aromatic hydrocarbons (PAH). Liver neoplasms occurred in brown bullhead from the Cuyahoga River and Munuscong Lake; brown bullhead captured from Munuscong Lake were older than those collected from the other locations. Brown bullhead from these same two rivers had elevated hepatosomatic indexes. No liver neoplasms were found in brown bullhead from the Fox and Menominee rivers, although polychlorinated aromatics were highest in both Fox River sediment and Fox and Menominee brown bullhead, and arsenic was highest in Menominee River sediment and fish. Liver neoplasms in brown bullhead from the Cuyahoga River fit the prevailing hypothesis that elevated PAH in sediment can induce cancer in wild fish. The cause of the liver neoplasms in Munuscong Lake brown bullhead is undetermined.
Turnipseed, D. Phil; Allen, Yvonne C.; Couvillion, Brady R.; McKee, Karen L.; Vervaeke, William C.
2014-01-01
The 2011 Mississippi River flood in the Lower Mississippi River Basin was one of the largest flood events in recorded history, producing the largest or next to largest peak streamflow for the period of record at a number of streamgages on the lower Mississippi River. Ecosystem effects include changes to wetlands, nutrient transport, and land accretion and sediment deposition changes. Direct effects to the wetland ecosystems in the Lower Mississippi River Basin were minimized because of the expansive levee system built to pass floodwaters. Nutrients carried by the Mississippi River affect water quality in the Lower Mississippi River Basin. During 2011, nutrient fluxes in the lower Mississippi River were about average. Generally, nutrient delivery of the Mississippi and Atchafalaya Rivers contributes to the size of the hypoxic zone in the Gulf of Mexico. Based on available limited post-flood satellite imagery, some land expansion in both the Wax Lake and Atchafalaya River Deltas was observed. A wetland sediment survey completed in June 2011 indicated that recent sediment deposits were relatively thicker in the Atchafalaya and Mississippi River (Birdsfoot) Delta marshes compared to marshes farther from these rivers.
[Distribution of diatoms in central city of Beijing].
Li, Li-Ping; Sun, Ting-Yi; Liu, Hong-Xia; Zhang, Hai-Dong; Bai, Ying-Jie; Wang, Rong-Shuai; Liu, Liang
2012-08-01
To explore the quantity and distribution of diatoms in main rivers and lakes in Xicheng, Dongcheng, Chaoyang, Haidian, Fengtai and Shijingshan Districts of the city of Beijing. Water samples were examined through the method of disorganizing, which were collected from 16 rivers and lakes in the central city of Beijing in September and October 2011. Diatom species and proportions of water samples were analyzed using DotSlide microscope station. A total of 10 species of diatoms were detected. Cyclotella, Synedra and Melosira etc. were found to be the dominant species via quantitative analysis. Significant differences were observed for diatom species and proportions among the different rivers and lakes. Melosira was found to be the dominant species in the Chang River; Synedra, in the Zhuan River, the Kunyu River and the Taoranting Park; Cyclotella, in the East Moat River, the Ba River, the Liangshui River and the Yongding River; and Navicula, in the Liangma River; Nitzschia, in the diversion canal of the Yongding River. The features of distribution of diatoms in the central city of Beijing are outlined. The morphological and relative constituent ratio database of diatoms are established in central city of Beijing.
Ecological comparisons of Lake Erie tributaries with elevated incidence of fish tumors
Smith, Stephen B.; Blouin, Marc A.; Mac, Michael J.
1994-01-01
Ecological comparisons were made between two Lake Erie tributaries (Black and Cuyahoga rivers) with contaminated sediments and elevated rates of tumors in fish populations and a third, relatively unpolluted, reference tributary, the Huron River. Fish populations, benthic invertebrates, and sediments were evaluated in all three Ohio rivers. Community structure analyses indicated similar total densities but lower species diversity for fish and benthic invertebrates in the contaminated rivers when compared with the reference river. Growth rates in fish from the contaminated areas were either similar to or higher than those offish from the reference site. Brown bullhead (Ameiurus nebulosus) from the two contaminated tributaries exhibited 51% (Black River) and 45% (Cuyahoga River) incidence of liver lesions (neoplastic and preneoplastic) as compared with a 4% incidence of liver lesions in brown bullhead from the reference river (Huron River). Incidence of external abnormalities on brown bullhead was 54% (Black River) and 73% (Cuyahoga River) as compared with a 14% incidence on fish from the Huron River. On a regional basis, incidence of external abnormalities on particular benthic fish species may be an effective method to quickly indicate areas for more intensive contaminant studies.
Caldwell, Rodney R.; Bowers, Craig L.
2003-01-01
Although trace-element concentrations sometimes exceeded aquatic-life criteria in the water of the Spokane River and were elevated above national median values in the bed sediment, trace-element concentrations of all river and ground-water samples were at levels less than U.S. Environmental Protection Agency drinking-water standards. The Spokane River appears to be a source of cadmium, copper, zinc, and possibly lead in the near-river ground water. Dissolved cadmium, copper, and lead concentrations generally were less than 1 microgram per liter (µg/L) in the river water and ground water. During water year 2001, dissolved zinc concentrations were similar in water from near-river wells (17-71 µg/L) and the river water (22-66 µg/L), but were less than detection levels in wells farther from the river. Arsenic, found to be elevated in ground water in parts of the aquifer, does not appear to have a river source. Although the river does influence the ground-water chemistry in proximity to the river, it does not appear to adversely affect the ground-water quality to a level of human-health concern.
Stability of backwater-influenced river bifurcations: A study of the Mississippi-Atchafalaya system
NASA Astrophysics Data System (ADS)
Edmonds, D. A.
2012-04-01
In this paper I use numerical modeling to show that the hydraulic backwater profile creates a feedback that may stabilize river bifurcations. The numerical model simulates flow and sediment transport in the Mississippi-Atchafalaya River system without the Old River Control Structure. The results show that bifurcation evolution strongly depends on the discharge upstream of the bifurcation. At upstream discharges greater than 12600 m3 s-1 the Atchafalaya River discharge increases through time at the expense of the Mississippi River. Interestingly, at upstream discharges lower than 12600 m3 s-1 the opposite occurs and the Mississippi River discharge increases at the expense of the Atchafalaya River. The capture direction changes because the backwater profile of each river varies enough at high and low discharge to invert the water surface slope ratio. These results suggest that the capture direction would change at high and low flow, which would have a stabilizing effect by preventing the runaway growth of one channel. Accounting for this, I calculate that in the absence of the Old River Control Structure capture would not happen catastrophically, but rather the Atchafalaya River would capture the Mississippi River in ˜300 years from present day.
Human impacts on river ice regime in the Carpathian Basin
NASA Astrophysics Data System (ADS)
Takács, Katalin; Nagy, Balázs; Kern, Zoltán
2014-05-01
River ice is a very important component of the cryosphere, and is especially sensitive to climatic variability. Historical records of appearance or disappearance and timing of ice phenomena are useful indicators for past climatic variations (Williams, 1970). Long-term observations of river ice freeze-up and break-up dates are available for many rivers in the temperate or cold region to detect and analyze the effects of climate change on river ice regime. The ice regime of natural rivers is influenced by climatic, hydrological and morphological factors. Regular ice phenomena observation mostly dates back to the 19th century. During this long-term observation period, the human interventions affecting the hydrological and morphological factors have become more and more intensive (Beltaos and Prowse, 2009). The anthropogenic effects, such as river regulation, hydropower use or water pollution causes different changes in river ice regime (Ashton, 1986). To decrease the occurrence of floods and control the water discharge, nowadays most of the rivers are regulated. River regulation changes the morphological parameters of the river bed: the aim is to create solid and equable bed size and stream gradient to prevent river ice congestion. For the satisfaction of increasing water demands hydropower is also used. River damming results a condition like a lake upstream to the barrage; the flow velocity and the turbulence are low, so this might be favourable for river ice appearance and freeze-up (Starosolsky, 1990). Water pollution affects ice regime in two ways; certain water contaminants change the physical characteristics of the water, e.g. lessens the freezing point of the water. Moreover the thermal stress effect of industrial cooling water and communal wastewater is also important; in winter these water sources are usually warmer, than the water body of the river. These interventions result different changes in the characteristic features of river ice regime. Selected examples from the Carpathian Basin represent some of the most common human impacts (engineering regulation, hydropower usage, water pollution), disturbing natural river ice regimes of mid-latitude rivers with densely populated or dynamically growing urban areas along their courses. In addition simple tests are also introduced to detect not only the climatic, but also the effect of anthropogenic impacts on river ice regime. As a result of river regulation on River Danube at Budapest a vanishing trend in river ice phenomena could be detected in the Danube records. The average ice-affected season shortened from 40 to 27 days, the average ice-covered season reduced greatly, from 27 to 7 days. In historical times the ice jams on the River Danube caused many times ice floods. The relative frequency of the break-up jam also decreased; moreover no ice flood occurred over the past 50 years. The changes due to hydropower usage are different upstream and downstream to the damming along the river. On Raba River upstream of the Nick dam at Ragyogóhíd, the ice-affected and ice-covered seasons were lengthened by 4 and 9 days, in contrast, downstream of the dam, the length of the ice-covered season was shortened by 7 days, and the number of ice-affected days decreased by 8 days at Árpás. During the observation period at Budapest on Danube River, the temperature requirements for river ice phenomena occurrence changed. Nowadays, much lower temperatures are needed to create the same ice phenomena compared to the start of the observations. For ice appearance, the mean winter air temperature requirements decreased from +2.39 °C to +1.71 °C. This investigation focused on anthropogenic effects on river ice regime, eliminating the impact of climatic conditions. Different forms of anthropogenic effects cause in most cases, a shorter length of ice-affected seasons and decreasing frequency of ice phenomena occurrence. Rising winter temperatures result the same changes in river ice regime. Climate change and river ice regime research should also take into account these anthropogenic impacts. Reference: Ashton, W.D. 1986. River and lake ice engineering. Water Resources Publication, USA 485 p. Starosolszky, Ö., 1990. Effect of river barrages on ice regime. Journal of Hydraulic Research 28/6, 711-718. Williams, G.P., 1970. A note on the break-up of lakes and rivers as indicators of climate change. Atmosphere 8 (1), 23-24.
Flood of August 24–25, 2016, Upper Iowa River and Turkey River, northeastern Iowa
Linhart, S. Mike; O'Shea, Padraic S.
2018-02-05
Major flooding occurred August 24–25, 2016, in the Upper Iowa River Basin and Turkey River Basin in northeastern Iowa following severe thunderstorm activity over the region. About 8 inches of rain were recorded for the 24-hour period ending at 4 p.m., August 24, at Decorah, Iowa, and about 6 inches of rain were recorded for the 24-hour period ending at 7 a.m., August 24, at Cresco, Iowa, about 14 miles northwest of Spillville, Iowa. A maximum peak-of-record discharge of 38,000 cubic feet per second in the Upper Iowa River at streamgage 05388250 Upper Iowa River near Dorchester, Iowa, occurred on August 24, 2016, with an annual exceedance-probability range of 0.2–1 percent. High-water marks were measured at six locations along the Upper Iowa River between State Highway 26 near the mouth at the Mississippi River and State Highway 76 about 3.5 miles south of Dorchester, Iowa, a distance of 15 river miles. Along the profiled reach of the Turkey River, a maximum peak-of-record discharge of 15,300 cubic feet per second at streamgage 05411600 Turkey River at Spillville, Iowa, occurred on August 24, 2016, with an annual exceedance-probability range of 1–2 percent. A maximum peak discharge of 35,700 cubic feet per second occurred on August 25, 2016, along the profiled reach of the Turkey River at streamgage 05411850 Turkey River near Eldorado, Iowa, with an annual exceedance-probability range of 0.2–1 percent. High-water marks were measured at 11 locations along the Turkey River between County Road B64 in Elgin and 220th Street, located about 4.5 miles northwest of Spillville, Iowa, a distance of 58 river miles. The high-water marks were used to develop flood profiles for the Upper Iowa River and Turkey River.
Implications of river morphology response to Dien Bien Phu fault in NW Vietnam
NASA Astrophysics Data System (ADS)
Lai, K.; Chen, Y.; Lam, D.
2007-12-01
In northern Vietnam, most rivers are flowing southeastward sub- or parallel to the valley of Red River and characterized by long but narrow catchments. The Dien Bien Phu fault is associated with the most seismically active zone in Vietnam and situated in the potential eastern boundary of the rotating southeastern Tibetan block. It cuts the Da River, the largest tributary of Red River in northwest Vietnam and has distorted the drainage basin resulting in complex river patterns. To assess the river morphology response to active Dien Bien Phu fault, we use 1/50,000 topographic data and ASTER images to map the precise river courses and digital elevation model data of SRTM to retrieve and analyze the river profiles. From the mapping results, the N-S striking fault results in three conspicuous north-trending river valleys coincided with the different fault segments to facilitate the measurement and reconstruction of the offsets along the fault. Further combining the longitudinal profile analysis we obtain ca. 10 km offsets by deflected river as the largest left-lateral displacement recorded along the active fault. The restored results show the downstream paleochannel of the Da River had been abandoned and becomes two small tributaries in opposite flow directions at present due to differential crustal uplift. Also the present crisscross valley at the junction of the Da River and the fault is resulted from the capture by another river which has been also deflected by the neotectonics. Based on our observations on river response, the Dien Bien Phu fault is a sinistral dominant fault with an uplift occurring in its eastern block. Furthermore the active Dien Bien Phu fault does not cut through the Red River northward indicating the western block of the fault can not be regarded as a single rigid block. There should be possible to find NW-SE trending faults paralleling to Red River to accommodate the deformation of the western block of the fault.
Implications of river morphology response to Dien Bien Phu fault in NW Vietnam
NASA Astrophysics Data System (ADS)
Lai, K.; Chen, Y.; Lam, D.
2004-12-01
In northern Vietnam, most rivers are flowing southeastward sub- or parallel to the valley of Red River and characterized by long but narrow catchments. The Dien Bien Phu fault is associated with the most seismically active zone in Vietnam and situated in the potential eastern boundary of the rotating southeastern Tibetan block. It cuts the Da River, the largest tributary of Red River in northwest Vietnam and has distorted the drainage basin resulting in complex river patterns. To assess the river morphology response to active Dien Bien Phu fault, we use 1/50,000 topographic data and ASTER images to map the precise river courses and digital elevation model data of SRTM to retrieve and analyze the river profiles. From the mapping results, the N-S striking fault results in three conspicuous north-trending river valleys coincided with the different fault segments to facilitate the measurement and reconstruction of the offsets along the fault. Further combining the longitudinal profile analysis we obtain ca. 10 km offsets by deflected river as the largest left-lateral displacement recorded along the active fault. The restored results show the downstream paleochannel of the Da River had been abandoned and becomes two small tributaries in opposite flow directions at present due to differential crustal uplift. Also the present crisscross valley at the junction of the Da River and the fault is resulted from the capture by another river which has been also deflected by the neotectonics. Based on our observations on river response, the Dien Bien Phu fault is a sinistral dominant fault with an uplift occurring in its eastern block. Furthermore the active Dien Bien Phu fault does not cut through the Red River northward indicating the western block of the fault can not be regarded as a single rigid block. There should be possible to find NW-SE trending faults paralleling to Red River to accommodate the deformation of the western block of the fault.
NASA Astrophysics Data System (ADS)
Wang, C.; Peifang, W.; Wang, X.; Hou, J.; Miao, L.
2017-12-01
Lotic river system plays an important part in water-vapor transfer and biogenic substances migration and transformation. Anthropogenic activities, including wastewater discharging and river damming, have altered river ecosystem and continuum. However, as the longest alpine river in China and suffered from increasing anthropogenic activities, the Yarlung Tsangpo River has been rarely studied. Recently, more attention has also been paid to the bacteria in river sediment as they make vital contributions to the biogeochemical nutrient cycling. Here, the distribution of biogenic substances, including nitrogen, phosphorus, silicon and carbon, was explored in both water and sediment of the Yarlung Tsangpo River. By using the next generation 16S rRNA sequencing, the bacterial diversity and structure in river sediment were presented. The results indicated that the nutrient concentrations increased in densely populated sites, revealing that biogenic substance distribution corresponded with the intensity of anthropogenic activity along the river. Nitrogen, phosphorus, silicon and carbon in water and sediment were all retained by the Zangmu Dam which is the only dam in the mainstream of the river. Moreover, the river damming decreased the biomass and diversity of bacteria in sediment, but no significant alteration of community structure was observed upstream and downstream of the dam. The most dominant bacteria all along the river was Proteobacteria. Meanwhile, Verrucomicrobia and Firmicutes also dominated the community composition in upstream and downstream of the river, respectively. In addition, total organic carbon (TOC) was proved to be the most important environmental factor shaping the bacterial community in river sediment. Our study offered the preliminary insights into the biogenic substance distribution and bacterial community in sediment along an alpine river which was affected by anthropogenic activities. In the future, more studies are needed to reveal the relationship between anthropogenic activity, biogenic substance cycling and bacterial community, especially along the alpine rivers.
NASA Astrophysics Data System (ADS)
Allen, G. H.; Pavelsky, T.
2015-12-01
The width of a river reflects complex interactions between river water hydraulics and other physical factors like bank erosional resistance, sediment supply, and human-made structures. A broad range of fluvial process studies use spatially distributed river width data to understand and quantify flood hazards, river water flux, or fluvial greenhouse gas efflux. Ongoing technological advances in remote sensing, computing power, and model sophistication are moving river system science towards global-scale studies that aim to understand the Earth's fluvial system as a whole. As such, a global spatially distributed database of river location and width is necessary to better constrain these studies. Here we present the Global River Width from Landsat (GRWL) Database, the first global-scale database of river planform at mean discharge. With a resolution of 30 m, GRWL consists of 58 million measurements of river centerline location, width, and braiding index. In total, GRWL measures 2.1 million km of rivers wider than 30 m, corresponding to 602 thousand km2 of river water surface area, a metric used to calculate global greenhouse gas emissions from rivers to the atmosphere. Using data from GRWL, we find that ~20% of the world's rivers are located above 60ºN where little high quality information exists about rivers of any kind. Further, we find that ~10% of the world's large rivers are multichannel, which may impact the development of the new generation of regional and global hydrodynamic models. We also investigate the spatial controls of global fluvial geomorphology and river hydrology by comparing climate, topography, geology, and human population density to GRWL measurements. The GRWL Database will be made publically available upon publication to facilitate improved understanding of Earth's fluvial system. Finally, GRWL will be used as an a priori data for the joint NASA/CNES Surface Water and Ocean Topography (SWOT) Satellite Mission, planned for launch in 2020.
Houser, J.N.; Richardson, W.B.
2010-01-01
Existing research on nutrients (nitrogen and phosphorus) in the Upper Mississippi River (UMR) can be organized into the following categories: (1) Long-term changes in nutrient concentrations and export, and their causes; (2) Nutrient cycling within the river; (3) Spatial and temporal patterns of river nutrient concentrations; (4) Effects of elevated nutrient concentrations on the river; and (5) Actions to reduce river nutrient concentrations and flux. Nutrient concentration and flux in the Mississippi River have increased substantially over the last century because of changes in land use, climate, hydrology, and river management and engineering. As in other large floodplain rivers, rates of processes that cycle nitrogen and phosphorus in the UMR exhibit pronounced spatial and temporal heterogeneity because of the complex morphology of the river. This spatial variability in nutrient processing creates clear spatial patterns in nutrient concentrations. For example, nitrate concentrations generally are much lower in off-channel areas than in the main channel. The specifics of in-river nutrient cycling and the effects of high rates of nutrient input on UMR have been less studied than the factors affecting nutrient input to the river and transport to the Gulf of Mexico, and important questions concerning nutrient cycling in the UMR remain. Eutrophication and resulting changes in river productivity have only recently been investigated the UMR. These recent studies indicate that the high nutrient concentrations in the river may affect community composition of aquatic vegetation (e. g., the abundance of filamentous algae and duckweeds), dissolved oxygen concentrations in off-channel areas, and the abundance of cyanobacteria. Actions to reduce nutrient input to the river include changes in land-use practices, wetland restoration, and hydrological modifications to the river. Evidence suggests that most of the above methods can contribute to reducing nutrient concentration in, and transport by, the UMR, but the impacts of mitigation efforts will likely be only slowly realized. ?? USGS, US Government 2010.
Stark, James R.
1996-01-01
Physical and aquatic biological conditions differ among the Mississippi River and its major tributaries (the St. Croix and Minnesota Rivers) in Minnesota and Wisconsin. The quality of surface water and the ecological condition of rivers affect the ways in which we use them. The St. Croix River is used for recreation; the Mississippi River is used for recreation and is a corridor for commerce; and the Minnesota River primarily drains agricultural lands. Analysis of the environmental framework of the basins and water-quality and ecological information by the National Water-Quality Assessment (NAWQA) Program shows that the conditions of the rivers are a product of a combination of factors including climate, hydrology, geology, soils, land use, land cover, water management, and water use.
Humin to Human: Organic carbon, sediment, and water fluxes along river corridors in a changing world
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sutfin, Nicholas Alan
This is a presentation with slides on What does it mean to be human? ...humin?; River flow and Hydrographs; Snake River altered hydrograph (Marston et al., 2005); Carbon dynamics are important in rivers; Rivers and streams as carbon sink; Reservoirs for organic carbon; Study sites in Colorado; River morphology; Soil sample collection; Surveys at RMNP; Soil organic carbon content at RMNP; Abandoned channels and Cutoffs; East River channel migration and erosion; Linking hydrology to floodplain sediment flux; Impact of Extreme Floods on Floodplain Sediment; Channel Geometry: RMNP; Beavers dams and multithread channels; Geomorphology and carbon in N. St. Vrain Creek;more » Geomorphology and carbon along the East River; Geomorphology and carbon in N. St. Vrain Creek; San Marcos River, etc.« less
River-aquifer interactions, geologic heterogeneity, and low-flow management
Fleckenstein, J.H.; Niswonger, R.G.; Fogg, G.E.
2006-01-01
Low river flows are commonly controlled by river-aquifer exchange, the magnitude of which is governed by hydraulic properties of both aquifer and aquitard materials beneath the river. Low flows are often important ecologically. Numerical simulations were used to assess how textural heterogeneity of an alluvial system influences river seepage and low flows. The Cosumnes River in California was used as a test case. Declining fall flows in the Cosumnes River have threatened Chinook salmon runs. A ground water-surface water model for the lower river basin was developed, which incorporates detailed geostatistical simulations of aquifer heterogeneity. Six different realizations of heterogeneity and a homogenous model were run for a 3-year period. Net annual seepage from the river was found to be similar among the models. However, spatial distribution of seepage along the channel, water table configuration and the level of local connection, and disconnection between the river and aquifer showed strong variations among the different heterogeneous models. Most importantly, the heterogeneous models suggest that river seepage losses can be reduced by local reconnections, even when the regional water table remains well below the riverbed. The percentage of river channel responsible for 50% of total river seepage ranged from 10% to 26% in the heterogeneous models as opposed to 23% in the homogeneous model. Differences in seepage between the models resulted in up to 13 d difference in the number of days the river was open for salmon migration during the critical fall months in one given year. Copyright ?? 2006 The Author(s).
Bi, Shipu; Yang, Yuan; Xu, Chengfen; Zhang, Yong; Zhang, Xiaobo; Zhang, Xianrong
2017-08-15
Estuary sediment is a major pollutant enrichment medium and is an important biological habitat. This sediment has attracted the attention of the marine environmental scientists because it is a more stable and effective medium than water for monitoring regional environmental quality conditions and trends. Based on a large amount of measurement data, we analyzed the concentrations, distribution, and sources of seven heavy metals (As, Cd, Cr, Cu, Hg, Pb, and Zn) in the surface sediment of typical estuaries that empty into the sea in eastern China: the Liaohe River Estuary, Yellow River Estuary, Yangtze River Estuary, Minjiang River Estuary, and Pearl River Estuary. The heavy metal concentrations in the sediments vary considerably from one estuary to the next. The Liaohe River Estuary sediment contains elevated levels of Cd, Hg, and Zn. The Yellow River Estuary sediment contains elevated levels of As. The sediments in the Yangtze River and Minjiang River estuaries contain elevated levels of Cd and Cu and of Pb and Zn, respectively. The sediment in the Pearl River Estuary contains elevated levels of all seven heavy metals. We used the Nemerow index method to assess the environment quality. The heavy metal pollution in the Liaohe River and Pearl River estuaries is more severe than that in the other estuaries. Additional work indicates that the heavy metal pollution in the Liaohe River and Pearl River estuaries is caused mainly by human activity. Copyright © 2017. Published by Elsevier Ltd.
Geomorphic Assessment of the Brazos River, Texas
NASA Astrophysics Data System (ADS)
Hamilton, P.; May, D.; Haring, C.
2017-12-01
The Brazos River is a large lowland river that traverses Texas before reaching the Gulf of Mexico. Of particular interest is the Brazos River reach through Fort Bend County, TX. This area is rapidly developing and as such there are concerns regarding infrastructure near the river. Rivers maintain a state of dynamic equilibrium wherein the system makes adjustments to external perturbations. This is of no concern in the abstract; the boundary conditions for the river change and the river adjusts to accommodate the change. However, because of development near the river, natural river adjustment can have catastrophic consequences. For example, bank failure along the Brazos River in Fort Bend County threatens SH 99, a major hurricane evacuation route, as well as flood control levees and county offices. Herein we present the results of hydraulic modeling conducted through the project area as well as the results of a geomorphic assessment. The Brazos River has a regional degradational trend throughout the project area in conjunction with subtly increasing sinuosity. Additionally, headcutting has greatly widened many of the tributary valleys and increased the local sediment supply to the river. Bank failure is an issue at several locations and there have been various solutions proposed for different sites. Part of the fear in addressing issues at a particular site is that money will be spent curing the symptoms along the river without confronting the underlying regional illness. Here we show some of the regional issues and how it they potentially interact with local solutions.
Discovery of ammocrypta clara (western sand darter) in the Upper Ohio River of West Virginia
Cincotta, Dan A.; Welsh, Stuart A.
2010-01-01
Ammocrypta clara Jordan and Meek (western sand darter) occurs primarily in the western portions of Mississippi River system, but also has been reported from a Lake Michigan drainage and a few eastern Texas Gulf Slope rivers. Additional range records depict a semi-disjunct distribution within the Ohio River drainage, including collections from Wabash River in Indiana, the Cumberland, Green, Kentucky and Big Sandy rivers of Kentucky, and the upper Tennessee River in Tennessee and Virginia. This paper documents the occurrence of A. clara from the upper Ohio River drainage within the lower Elk River, West Virginia, based on collections from 1986, 1991, 1995, 2005 and 2006. The Elk River population, consistent with those of other Ohio River drainages, has slightly higher counts for numbers of dorsal-fin rays, scales below lateral line and lateral line scales when compared to data from populations outside of the Ohio River drainage. Modal counts of meristic characters are similar among populations, except for higher modal counts of lateral line scales in the Ohio River population. The discovery of the Elk River population extends the range distribution of A. clara in the Eastern Highlands region, documents wide distributional overlap and additional sympatry with its sister species,A. pellucida (eastern sand darter), and softens support for an east-west Central Highlands vicariance hypothesis for the present distribution of A. clara and A. pellucida.
76 FR 54415 - Proposed Flood Elevation Determinations
Federal Register 2010, 2011, 2012, 2013, 2014
2011-09-01
... following flooding sources: Bear Creek (backwater effects from Cumberland River), Big Renox Creek (backwater effects from Cumberland River), Big Whetstone Creek (backwater effects from Cumberland River), Big Willis... River), Big Renox Creek (backwater effects from Cumberland River), Big Whetstone Creek (backwater...
Dissolved silica in the tidal Potomac River and Estuary, 1979-81 water years
Blanchard, Stephen F.
1988-01-01
The Potomac River at Chain Bridge is the major riverine source of dissolved silica (DSi) to the tidal Potomac River and Estuary. DSi concentrations at Chain Bridge are positively correlated with river discharge; river discharge is an important factor controlling rates of supply, dilution, and residence time. When river flow is high, the longitudinal DSi distribution is conservative. When river flow is low, other processes, such as phytoplankton uptake, benthic flux, resuspension, ground-water discharge, and water-column dissolution of diatoms, tend to be more influential than the river. Elevated concentrations of DSi in sewage-treatment-plant effluent in the Washington, D.C., area raise the DSi concentration of receiving Potomac River water. The tidal river zone serves as a net sink for DSi as a result of phytoplankton uptake. Ultimately, the biogenic silica from the tidal river is transported to the transition zone, where it is mineralized. As a result, the DSi concentration in the transition zone increases during summer. The DSi concentrations in the estuarine zone are largely controlled by dilution by Chesapeake Bay water and by phytoplankton uptake.
Biological surveys on the Savannah River in the vicinity of the Savannah River Plant (1951-1976)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Matthews, R. A.
In 1951, the Academy of Natural Sciences of Philadelphia was contracted by the Savannah River Plant to initiate a long-term monitoring program in the Savannah River. The purpose of this program was to determine the effect of the Savannah River Plant on the Savannah River aquatic ecosystem. The data from this monitoring program have been computerized by the Savannah River Laboratory, and are summarized in this report. During the period from 1951-1976, 16 major surveys were conducted by the Academy in the Savannah River. Water chemistry analyses were made, and all major biological communities were sampled qualitatively during the springmore » and fall of each survey year. In addition, quantitative diatom data have been collected quarterly since 1953. Major changes in the Savannah River basin, in the Savannah River Plant's activities, and in the Academy sampling patterns are discussed to provide a historical overview of the biomonitoring program. Appendices include a complete taxonomic listing of species collected from the Savannah River, and summaries of the entire biological and physicochemical data base.« less
Scaling properties reveal regulation of river flows in the Amazon through a forest reservoir
NASA Astrophysics Data System (ADS)
Salazar, Juan Fernando; Villegas, Juan Camilo; María Rendón, Angela; Rodríguez, Estiven; Hoyos, Isabel; Mercado-Bettín, Daniel; Poveda, Germán
2018-03-01
Many natural and social phenomena depend on river flow regimes that are being altered by global change. Understanding the mechanisms behind such alterations is crucial for predicting river flow regimes in a changing environment. Here we introduce a novel physical interpretation of the scaling properties of river flows and show that it leads to a parsimonious characterization of the flow regime of any river basin. This allows river basins to be classified as regulated or unregulated, and to identify a critical threshold between these states. We applied this framework to the Amazon river basin and found both states among its main tributaries. Then we introduce the forest reservoir
hypothesis to describe the natural capacity of river basins to regulate river flows through land-atmosphere interactions (mainly precipitation recycling) that depend strongly on the presence of forests. A critical implication is that forest loss can force the Amazonian river basins from regulated to unregulated states. Our results provide theoretical and applied foundations for predicting hydrological impacts of global change, including the detection of early-warning signals for critical transitions in river basins.
Geocode of River Networks in Global Plateaus
NASA Astrophysics Data System (ADS)
Ni, J.; Wang, Y.; Wang, T.
2017-12-01
As typical hierarchical systems, river networks are of great significance to aquatic organisms and its diversity. Different aspects of river networks have been investigated in previous studies such as network structure, formation cause, material transport, nutrient cycle and habitat variation. Nevertheless, river networks function as biological habitat is far from satisfactory in plateau areas. This paper presents a hierarchical method for habitat characterization of plateau river networks with the geocode extracted from abiotic factors including historical geologic period, climate zone, water source and geomorphic process at different spatial scales. As results, characteristics of biological response with vertical differentiation within typical plateau river networks are elucidated. Altitude, climate and landform are of great influence to habitat and thereby structure of aquatic community, while diverse water source and exogenic action would influence biological abundance or spatiotemporal distribution. Case studies are made in the main stream of the Yellow River and the Yangtze River, respectively extended to the river source to Qinghai-Tibet Plateau, which demonstrate high potentials for decision making support to river protection, ecological rehabilitation and sustainable management of river ecosystems.
14 CFR 93.351 - General requirements for operating in the East River and/or Hudson River Exclusions.
Code of Federal Regulations, 2010 CFR
2010-01-01
... TRAFFIC RULES New York Class B Airspace Hudson River and East River Exclusion Special Flight Rules Area... River or Hudson River as depicted on the New York VFR Terminal Area Chart (TAC) and/or New York Helicopter Route Chart. (d) Have a current New York TAC chart and/or New York Helicopter Route Chart in the...
Rivers as Political Boundaries: Peru and its Dynamic Borders
NASA Astrophysics Data System (ADS)
Abad, J. D.; Escobar, C.; Garcia, A. M. P.; Ortals, C.; Frias, C. E.; Vizcarra, J.
2014-12-01
Rivers, although inherently dynamic, have been chosen as political boundaries since the beginning of colonization for several reasons. Such divisions were chosen namely for their defensive capabilities and military benefits, and because they were often the first features mapped out by explorers. Furthermore, rivers were indisputable boundaries that did not require boundary pillars or people to guard them. However, it is important to understand the complexities of a river as a boundary. All rivers inevitably change over time through processes such as accretion, deposition, cut-off, or avulsion, rendering a political boundary subject to dispute. Depending upon the flow, size, and surrounding land, a river will migrate differently than others. As these natural features migrate one country loses land while another gains land leading to tension between legal rigidity and fluid dynamism. This in turn can manifest in social disruption due to cultural differences, political upheaval, or conflict risk as a result of scarce water resources. The purpose of this research is to assess the temporal and spatial variability of the political boundaries of Peru that follow rivers. Peru shares borders with Colombia, Brazil, Bolivia, Chile, and Ecuador. A large part of its northern border with Colombia follows the Putumayo River and later the Amazon River. Part of its eastern border with Brazil follows the Yavari River and later the Yaquirana River. These rivers are natural features used as political boundaries yet they differ in how each migrates. By means of a spatial and temporal analysis of satellite images it was possible to obtain erosion and deposition areas for the Putumayo River, the portion of the Amazon River that is part of the Peruvian boundary, the Yavari River, and the Yaquirana River. The erosion and deposition areas were related to land distribution among Peru, Colombia, and Brazil. By examining the Digital Elevation Model one can see how the altitude of the surrounding land affects the watersheds and thus better understand the dynamic of rivers. Ultimately, this research combines data regarding the morphodynamics of these rivers with historical insight on border treaties in order to gain a comprehensive understanding of political implications and social repercussions of dynamic boundaries.
Thieme, Michele L.; McIvor, Carole; Brouder, Mark J.; Hoffnagle, Timothy L.
2001-01-01
Flannelmouth sucker, Catostomus latipinnis, a fish endemic to the Colorado River basin in the western United States, appears to experience poor recruitment to adult size in the Colorado River, downstream of Glen Canyon Dam. Lack or impermanence of rearing areas for young-of-year (YOY) fish is hypothesized to be the problem. Knowing the importance of tributary mouths as rearing areas in other river systems, we studied use of the mouth of the Paria River, a tributary of the Colorado River, by YOY flannelmouth suckers, and the availability of rearing area in the mouth at different flow levels in the Colorado River in 1996 and 1997. We also examined the relationship between flash floods in the Paria River and catch-per-unit-effort (CPUE) of YOY in the Paria River between 1991 and 1996.Maximum mean daily discharge in the Paria River was inversely correlated with CPUE of YOY flannelmouth suckers (Spearman Rho=−0.9856, p=0.0003) during their critical rearing period (15 March–30 June). Thus, it appears that YOY flannelmouth suckers rear longer in the Paria River in years when flash flooding is minimal.Recruitment of YOY flannelmouth suckers at the Paria River may also be improved by enhancing pool formation during spring and summer rearing seasons. YOY flannelmouth sucker was captured in a pool created by high Colorado River flows (≥336 m3/s) that inundated the mouth of the Paria River during spring and summer, 1996. In 1997, high flows (about 550–750 m3/s) in the Colorado River during winter and spring initially inundated the Paria River and formed a pool in the mouth. However, these high flows eventually caused 0.5–1.0 m of suspended sediment from the incoming Paria River to deposit in the mouth. Thus, despite higher flows than 1996, the slackwater area formed only occasionally in 1997. Differences in pool formation between 1996 and 1997 demonstrate that pool formation cannot be inferred solely from Colorado River flows.
Wilson, Timothy P.; Bonin, Jennifer L.
2008-01-01
Samples of surface water and suspended sediment were collected from the Passaic and Elizabeth Rivers and their tributaries in New Jersey from July 2003 to February 2004 to determine the concentrations of selected chlorinated organic and inorganic constituents. This sampling and analysis was conducted as Phase II of the New York-New Jersey Harbor Estuary Workplan?Contaminant Assessment and Reduction Program (CARP), which is overseen by the New Jersey Department of Environmental Protection. Phase II of the New Jersey Workplan was conducted to define upstream tributary and point sources of contaminants in those rivers sampled during Phase I work, with special emphasis on the Passaic and Elizabeth Rivers. Samples were collected from three groups of tributaries: (1) the Second, Third, and Saddle Rivers; (2) the Pompton and upper Passaic Rivers; and (3) the West Branch and main stem of the Elizabeth River. The Second, Third, and Saddle Rivers were sampled near their confluence with the tidal Passaic River, but at locations not affected by tidal flooding. The Pompton and upper Passaic Rivers were sampled immediately upstream from their confluence at Two Bridges, N.J. The West Branch and the main stem of the Elizabeth River were sampled just upstream from their confluence at Hillside, N.J. All tributaries were sampled during low-flow discharge conditions using the protocols and analytical methods for organic constituents used in low-flow sampling in Phase I. Grab samples of streamflow also were collected at each site and were analyzed for trace elements (mercury, methylmercury, cadmium, and lead) and for suspended sediment, particulate organic carbon, and dissolved organic carbon. The measured concentrations and available historical suspended-sediment and stream-discharge data (where available) were used to estimate average annual loads of suspended sediment and organic compounds in these rivers. Total suspended-sediment loads for 1975?2000 were estimated using rating curves developed from historical U.S. Geological Survey (USGS) suspended-sediment and discharge data, where available. Average annual loads of suspended sediment, in millions of kilograms per year (Mkg/yr), were estimated to be 0.190 for the Second River, 0.23 for the Third River, 1.00 for the Saddle River, 1.76 for the Pompton River, and 7.40 for the upper Passaic River. On the basis of the available discharge records, the upper Passaic River was estimated to provide approximately 60 percent of the water and 80 percent of the total suspended-sediment load at the Passaic River head-of-tide, whereas the Pompton River provided roughly 20 percent of the total suspended-sediment load estimated at the head-of-tide. The combined suspended-sediment loads of the upper Passaic and Pompton Rivers (9.2 Mkg/yr), however, represent only 40 percent of the average annual suspended-sediment load estimated for the head-of-tide (23 Mkg/yr) at Little Falls, N.J. The difference between the combined suspended-sediment loads of the tributaries and the estimated load at Little Falls represents either sediment trapped upriver from the dam at Little Falls, additional inputs of suspended sediment downstream from the tributary confluence, or uncertainty in the suspended-sediment and discharge data that were used. The concentrations of total suspended sediment-bound polychlorinated biphenyls (PCBs) in the tributaries to the Passaic River were 194 ng/g (nanograms per gram) in the Second River, 575 ng/g in the Third River, 2,320 ng/g in the Saddle River, 200 ng/g in the Pompton River, and 87 ng/g in the upper Passic River. The dissolved PCB concentrations in the tributaries were 563 pg/L (picograms per liter) in the Second River, 2,510 pg/L in the Third River, 2,270 pg/L in the Saddle River, 887 pg/L in the Pompton River, and 1,000 pg/L in the upper Passaic River. Combined with the sediment loads and discharge, these concentrations resulted in annual loads of suspended sediment-bound PCBs, i
Exploring Controls on Sinuousity, Terraces and River Capture in the Upper Dajia River, Taiwan
NASA Astrophysics Data System (ADS)
Belliveau, L. C.; Ouimet, W. B.; Chan, Y. C.; Byrne, T. B.
2015-12-01
Taiwan is one of the most tectonically active regions in the world and is prone to landslides due to steep topography, large earthquakes and frequent typhoons. Landslides often affect and alter the river valleys beneath them, producing knickpoints on longitudinal river profiles, segmenting valleys into mixed bedrock-alluvial rivers and affecting river incision for tens to thousands of years. This study investigates the origin and evolution of complex channel morphologies, terraces and river capture along a 20km stretch of the Upper Da-Jia River in the Heping area of Taiwan. Through GIS analysis and field studies, we explore controls on river channel sinuousity, terrace development and river capture in relation to tectonic and climatic forcing, rock erodibility and landslides. High channel sinuousity is proposed as the result of a coupling between bank erosion and landslides. We discuss three types of landslide-induced meanders and increased sinuousity: (a) depositional-push meanders, (b) failure-zone erosional meanders, and (c) complex-erosional meanders. We also investigate spatial variation in channel morphology (slope, width) and the distribution and heights of river terraces within the Upper Da-Jia watershed associated with periods of widespread valley filling from landslide activity. Examples of river capture provide further evidence of the dynamic interactions between river incision, landslides and associated changes in channel morphology and terrace development within steep rapidly uplift, eroding and evolving mountain belts.
Reconnaissance Report for Upper Mississippi River Navigation Study. (Revised)
1992-09-01
Contaminants may include ammonia, arsenic, cadmium , chlordane, chromium, copper, dioxins, lead, nickel, nitrogen, PCBs, phosphorus, zinc, various...al 1981 Rock River, Upper Mississippi River, Little Wabash River, Lower Wabash River Units (I, III-north, aid VIII). In Predictive Models in Illinois
Application of HEC-6 to ephemeral rivers of Arizona
DOT National Transportation Integrated Search
1986-01-01
The U.S. Army Corps of Engineers, computer program HEC-6--"Scour and Deposition in Rivers and Reservoirs" was applied to three ephemeral rivers of Arizona--Agua Fria River, Salt River, and Rillito Creek. The input data development techniques and resu...
A SEDIMENT TOXICITY EVALUATION OF THREE LARGE RIVER SYSTEMS
Sediment toxicity samples were collected from selected sites on the Ohio River, Missouri River and upper Mississippi River as part of the 2004 and 2005 Environmental Monitoring and Assessment Program-Great Rivers Ecosystems Study (EMAP-GRE). Samples were collected by compositing...
NASA Astrophysics Data System (ADS)
Rowland, J. C.; Dietrich, W. E.; Day, G.
2005-05-01
Along lowland river systems across the globe the exchange of water, sediment, carbon, nutrients and biota between main stem rivers and off-river water bodies (ORWB) is facilitated by the presence of stable secondary channels referred to here as tie channels. Sixty five percent of the ORWB along the middle Fly River in Papua New Guinea connect to the river through such channels. A similar percentage of the 37 ORWB located between Baton Rouge and Memphis on the lower Mississippi River at one time were linked to the river by tie or batture (as they are locally known) channels. Levee construction and other alterations aimed at flood control or navigation on the Mississippi have left only a handful of lakes connected to the river, of these, most are heavily altered by dredging or other modifications. Tie channels were also once common along major tributaries to the Mississippi, such as the Red River. In the much less disturbed Alaskan environment, tie channels are still common, especially along Birch Creek and the Koyukuk and Black rivers. Our studies on the Mississippi River, in Alaska and in Papua New Guinea indicate that tie channels possess a common channel form that is stable and self-maintaining for hundreds to possibly a thousand years. Tie channels exhibit narrow width to depth ratios (~ 5.5) and consistently scale in cross-sectional dimensions to the size of the lake into which they flow. Variations in river and lake stage drive flow bi-directionally through tie channels. A local high or sill in the bed of tie channels controls the degree and duration of connection between the river and ORWB, with many lakes becoming isolated during periods of low stage. The life-span of a tie channel depends on the rate of sediment loading to the ORWB. Our research indicates that this rate directly corresponds to the sediment loading in the main stem river. Along the Fly River, for example, a 5 to 7 fold increase in the river sediment load has resulted increases of 6 to 17 times in tie channel progradation rates. In a few instances Fly River tie channels have become filled with sediment following the increase in sediment loading. The precise role of tie channels in the ecology of lowland river systems has yet to be quantified, but given their critical role in connecting rivers with floodplain habitats it is likely they provide an important source of refuge, breeding habitat, and biomass production for many aquatic organisms. As restoration efforts increasingly focus on the improving or reestablishing connectivity between lowland rivers and their floodplains, consideration should be given as to whether tie channels are an important missing component of such systems.
Warrick, Jonathan A.; Draut, Amy E.; McHenry, Michael L.; Miller, Ian M.; Magirl, Christopher S.; Beirne, Matthew M.; Stevens, Andrew Stevens; Logan, Joshua B.; Duda, Jeffrey J.; Warrick, Jonathan A.; Magirl, Christopher S.
2011-01-01
The removal of two dams on the Elwha River will introduce massive volumes of sediment to the river, and this increase in sediment supply in the river will likely modify the shapes and forms of the river and coastal landscape downstream of the dams. This chapter provides the geologic and geomorphologic background of the Olympic Peninsula and the Elwha River with emphasis on the present river and shoreline. The Elwha River watershed was formed through the uplift of the Olympic Mountains, erosion and movement of sediment throughout the watershed from glaciers, and downslope movement of sediment from gravitational and hydrologic forces. Recent alterations to the river morphology and sediment movement through the river include the two large dams slated to be removed in 2011, but also include repeated bulldozing of channel boundaries, construction and maintenance of flood plain levees, a weir and diversion channel for water supply purposes, and engineered log jams to help enhance river habitat for salmon. The shoreline of the Elwha River delta has changed in location by several kilometers during the past 14,000 years, in response to variations in the local sea-level of approximately 150 meters. Erosion of the shoreline has accelerated during the past 80 years, resulting in landward movement of the beach by more than 200 meters near the river mouth, net reduction in the area of coastal wetlands, and the development of an armored low-tide terrace of the beach consisting primarily of cobble. Changes to the river and coastal morphology during and following dam removal may be substantial, and consistent, long-term monitoring of these systems will be needed to characterize the effects of the dam removal project.
Beeman, John W.; Hansel, Hal; Juhnke, Steve; Stutzer, Greg
2009-01-01
The survival of hatchery-origin juvenile coho salmon from the Trinity River Hatchery was estimated as they migrated seaward through the Trinity and Klamath Rivers. The purpose of the study was to collect data for comparison to a similar study in the Klamath River and provide data to the Trinity River Restoration Program. A total of 200 fish fitted with radio transmitters were released into the Trinity River near the hatchery (river kilometer 252 from the mouth of the Klamath River) biweekly from March 19 to May 28, 2008. Fish from the earliest release groups took longer to pass the first detection site 10 kilometers downstream of the hatchery than fish from the later release groups, but travel times between subsequent sites were often similar among the release groups. The travel times of individuals through the 239 kilometer study area ranged from 15.5 to 84.6 days with a median of 43.3 days. The data and models did not support differences in survival among release groups, but did support differences among river reaches. The probability of survival in the first 53 kilometers was lower than in the reaches farther downstream, which is similar to trends in juvenile coho salmon in the Klamath River. The lowest estimated survival in this study was in the first 10 kilometers from release in the Trinity River (0.676 SE 0.036) and the highest estimated survival was in the final 20 kilometer reach in the Klamath River (0.987 SE 0.013). Estimated survivals of radio-tagged juvenile coho salmon from release to Klamath River kilometer 33 were 0.639 per 100 kilometers for Trinity River fish and 0.721 per 100 kilometers for Klamath River fish.
Vining, Kevin C.; Chase, Katherine J.; Loss, Gina R.
2013-01-01
Excessive precipitation produced severe flooding in the Mississippi River and Red River of the North Basins during spring and summer 2011. The 2011 flooding was caused by weather conditions that were affected in part by a La Niña climate pattern. During the 2010–11 climatological winter (December 2010–February 2011), several low pressure troughs from the Rocky Mountains into the Ohio River subbasin produced large amounts of precipitation. Precipitation was above normal to record amounts in parts of the Missouri River, Red River of the North, and upper Mississippi River subbasins, and mostly normal to below normal in the Ohio River and lower Mississippi River subbasins. During the 2011 climatological spring (March–May 2011), a large low pressure trough over the continental States and a high pressure ridge centered in the vicinity of the Gulf of Mexico combined to produce storms with copious precipitation along frontal boundaries across the Central States. Rain totals recorded during the April 18–28, 2011, precipitation event were more than 8 inches at several locations, while an impressive total of 16.15 inches was recorded at Cape Girardeau, Missouri. Several locations in the Missouri River subbasin had rainfall totals that were nearly one-third to one-half of their 1971–2000 normal annual amounts during a May 16–31, 2011, precipitation event. During June and July, thunderstorm development along frontal boundaries resulted in areas of heavy rain across the Missouri River, Red River of the North, and upper Mississippi River subbasins, while rainfall in the lower Mississippi River subbasin was mostly below normal.
Geologic map of the Masters 7.5' quadrangle, Weld and Morgan Counties, Colorado
Berry, Margaret E.; Slate, Janet L.; Paces, James B.; Hanson, Paul R.; Brandt, Theodore R.
2015-09-28
The Masters 7.5' quadrangle is located along the South Platte River corridor on the semiarid plains of eastern Colorado and contains surficial deposits that record alluvial, eolian, and hillslope processes that have operated in concert with environmental changes from Pleistocene to present time. The South Platte River, originating high in the Colorado Front Range, has played a major role in shaping the surficial geology of the quadrangle, which is situated downstream of where the last of the major headwater tributaries (St. Vrain, Big Thompson, and Cache la Poudre) join the river. Recurrent glaciation (and deglaciation) of basin headwaters affected river discharge and sediment supply far downstream, influencing deposition of alluvium and terrace formation in the Masters quadrangle. Kiowa and Bijou Creeks, unglaciated tributaries originating in the Colorado Piedmont east of the Front Range and joining the South Platte River just downstream of the Masters quadrangle, also have played a major role by periodically delivering large volumes of sediment to the river during flood events, which may have temporarily dammed the river. Eolian sand deposits of the Greeley (north of river) and Fort Morgan (south of river) dune fields cover much of the quadrangle and record past episodes of sand mobilization during times of prolonged drought. With the onset of irrigation and damming during historical times, the South Platte River has changed from a broad, shallow sandy braided river with highly seasonal discharge to a much narrower, deeper river with braided-meandering transition morphology and more uniform discharge. Along the reach of river in the Masters quadrangle, the river has incised into Upper Cretaceous Pierre Shale, which, although buried by alluvial deposits here, is locally exposed downstream along the South Platte River bluff near the Bijou Creek confluence, in some of the larger draws, and along Wildcat Creek.
Distributions of small nongame fishes in the lower Yellowstone River
Duncan, Michael B.; Bramblett, Robert G.; Zale, Alexander V.
2016-01-01
The Yellowstone River is the longest unimpounded river in the conterminous United States. It has a relatively natural flow regime, which helps maintain diverse habitats and fish assemblages uncommon in large rivers elsewhere. The lower Yellowstone River was thought to support a diverse nongame fish assemblage including several species of special concern. However, comprehensive data on the small nongame fish assemblage of the lower Yellowstone River is lacking. Therefore, we sampled the Yellowstone River downstream of its confluence with the Clark’s Fork using fyke nets and otter trawls to assess distributions and abundances of small nongame fishes. We captured 42 species (24 native and 18 nonnative) in the lower Yellowstone River with fyke nets. Native species constituted over 99% of the catch. Emerald shiners Notropis atherinoides, western silvery minnows Hybognathus argyritis, flathead chubs Platygobio gracilis, sand shiners Notropis stramineus, and longnose dace Rhinichthys cataractae composed nearly 94% of fyke net catch and were caught in every segment of the study area. We captured 24 species by otter trawling downstream of the Tongue River. Sturgeon chubs Macrhybopsis gelida, channel catfish Ictalurus punctatus, flathead chubs, stonecats Noturus flavus, and sicklefin chubs Macrhybopsis meeki composed 89% of the otter trawl catch. The upstream distributional limit of sturgeon chubs in the Yellowstone River was the Tongue River; few sicklefin chubs were captured above Intake Diversion Dam. This study not only provides biologists with baseline data for future monitoring efforts on the Yellowstone River but serves as a benchmark for management and conservation efforts in large rivers elsewhere as the Yellowstone River represents one of the best references for a naturally functioning Great Plains river.
Occurrence of pesticides in five rivers of the Mississippi Embayment Study Unit, 1996-98
Coupe, Richard H.
2000-01-01
The occurrence and temporal distribution of more than 80 pesticides and pesticide metabolites were determined in five rivers of the Mississippi Embayment National Water-Quality Assessment study unit from February 1996 through January 1998. More than 230 samples were collected and analyzed during the 2-year study. The five rivers sampled included three rivers with small, primarily agricultural watersheds; one river with a small urban watershed in Memphis, Tennessee; and one large river with mixed land use (row-crop agriculture, pasture, forest, and urban). Pesticides, usually herbicides, were frequently detected in water samples from every river. Insecticides were frequently detected (chlorpyrifos and diazinon in all samples) only in the river that drains the urban watershed. The occurrence of pesticides in surface water varied among the agricultural watersheds as well as between the agricultural and urban watersheds. The pesticides detected in the rivers that drain the agricultural watersheds were related to the major crop types cultivated in the watershed?corn is mostly grown in the northern part of the study unit, whereas cotton and rice are mostly grown in the southern part. The occurrence of pesticides in the Yazoo River, which drains the mixed land-use watershed, was similar to pesticide occurrence in the rivers that drain smaller agricultural watersheds, although concentrations were lower in the Yazoo River. Likewise, simazine, which was detected in all urban stream samples, was also detected in all Yazoo River samples, but in lower concentrations. The aquatic-life criteria for diazinon and chlorpyrifos was exceeded in 24 of 25 and 12 of 25 urban river samples, respectively, but only once or twice in agricultural and mixed-use watershed samples. Atrazine exceeded the aquatic-life criterion in about 20 percent of the samples from each river, particularly in the spring following pesticide application.
Paraiba do Sul river delta, Brazil
1996-01-20
STS072-738-019 (11-20 Jan. 1996) --- The Delta of the Paraiba do Sul River, northeast of Rio de Janeiro, Brazil, stands out in this 70mm frame exposed from the Earth-orbiting Space Shuttle Endeavour. The brown color of the river water and offshore sediment plume show that the river is in flood stage. This delta attracts much attention from orbit because of its prominent beach ridges either side of the river mouth. River sediment from inland supplies the material which is redistributed by coastal currents to form the parallel beach ridges. The lower 20 miles of the river appear in this scene. The river flows into the Atlantic in an easterly direction.
Dynamic reorganization of river basins.
Willett, Sean D; McCoy, Scott W; Perron, J Taylor; Goren, Liran; Chen, Chia-Yu
2014-03-07
River networks evolve as migrating drainage divides reshape river basins and change network topology by capture of river channels. We demonstrate that a characteristic metric of river network geometry gauges the horizontal motion of drainage divides. Assessing this metric throughout a landscape maps the dynamic states of entire river networks, revealing diverse conditions: Drainage divides in the Loess Plateau of China appear stationary; the young topography of Taiwan has migrating divides driving adjustment of major basins; and rivers draining the ancient landscape of the southeastern United States are reorganizing in response to escarpment retreat and coastal advance. The ability to measure the dynamic reorganization of river basins presents opportunities to examine landscape-scale interactions among tectonics, erosion, and ecology.
NASA Astrophysics Data System (ADS)
Wang, Gaoxu; Zeng, Xiaofan; Zhao, Na; He, Qifang; Bai, Yiran; Zhang, Ruoyu
2018-02-01
The relationships between the river discharge and the precipitation in the Jinsha River basin are discussed in this study. In addition, the future precipitation trend from 2011-2050 and its potential influence on the river discharge are analysed by applying the CCLM-modelled precipitation. According to the observed river discharge and precipitation, the annual river discharge at the two main hydrological stations displays good correlations with the annual precipitation in the Jinsha River basin. The predicted future precipitation tends to change similarly as the change that occurred during the observation period, whereas the monthly distributions over a year could be more uneven, which is unfavourable for water resources management.
River water quality and pollution sources in the Pearl River Delta, China.
Ouyang, Tingping; Zhu, Zhaoyu; Kuang, Yaoqiu
2005-07-01
Some physicochemical parameters were determined for thirty field water samples collected from different water channels in the Pearl River Delta Economic Zone river system. The analytical results were compared with the environmental quality standards for surface water. Using the SPSS software, statistical analyses were performed to determine the main pollutants of the river water. The main purpose of the present research is to investigate the river water quality and to determine the main pollutants and pollution sources. Furthermore, the research provides some approaches for protecting and improving river water quality. The results indicate that the predominant pollutants are ammonium, phosphorus, and organic compounds. The wastewater discharged from households in urban and rural areas, industrial facilities, and non-point sources from agricultural areas are the main sources of pollution in river water in the Pearl River Delta Economic Zone.
NASA Astrophysics Data System (ADS)
Govers, G.; Omengo, F.; Geeraert, N.; Bouillon, S.; Neyens, G.
2016-12-01
The lower Tana river in Kenya is an active river carrying high sediment and carbon loads, while lateral influxes from tributaries are very limited. We used this river as a natural laboratory to study the dynamics of carbon in the river-floodplain system. We measured carbon fluxes in the river as well as rates of carbon processing. Furthermore, we assessed carbon deposition in the floodplain and carbon mobilisation by river migration. We show that both within-river carbon dynamics as well as river-floodplain interaction can only be understood by accounting for autogenic river processes: the amounts of sediment (5-6 Mt yr-1) and particulate organic carbon (120-180 Mg yr-1) that are re-mobilised within the river reach (300 km) are similar to the amounts the reach receives from upstream. Carbon and sediment mobilisation are compensated for by deposition, both in the floodplain and within the river (point bars). This intensive exchange explains why the suspended sediment in the Tana river becomes finer (and more enriched in carbon) in the downstream direction, despite the deposition of fine, carbon-rich sediments in the floodplain. Contrary to what is found in temperate floodplains, overall carbon burial appears not to be very effective: most buried carbon is mineralised within decades after burial. However, burial efficiency is much higher for allochthonous organic carbon (deposited by the river) than for autochthonous organic carbon (sourced from local primary production). The Tana river does not only exchange carbon with its floodplain through deposition and remobilisation of POC. When floods occur, the floodplain acts as an important source of dissolved organic and inorganic carbon which is not only produced by organic carbon decomposition but also by weathering. Finally, there is significant CO2 outgassing from the Tana river, releasing 3-5 Mg C yr-1 to the atmosphere. Our study highlights the role of tropical river corridors as highly dynamic environments, which may be strongly affected by human management and/or climatic change. The planned construction of a major dam in the upper Tana is likely to steady the river's discharge and will limit lateral river migration and flooding, which may transform the lower Tana from a net sediment (and to a lesser extent, carbon) sink to a source.
Channel Bank Cohesion and the Maintenance of Suspension Rivers
NASA Astrophysics Data System (ADS)
Dunne, K. B. J.; Jerolmack, D. J.
2017-12-01
Gravel-bedded rivers organize their channel geometry and grain size such that transport is close to the threshold of motion at bankfull. Sand-bedded rivers, however, typically maintain bankfull fluid shear (or Shields) stresses far in excess of threshold; there is no widely accepted explanation for these "suspension rivers". We propose that all alluvial rivers are at the threshold of motion for their erosion-limiting material, i.e., the structural component of the river cross-section that is most difficult to mobilize. The entrainment threshold of gravel is large enough that bank cohesion has little influence on gravel-bed rivers. Sand, however, is the most easily entrained material; silt and clay can raise the entrainment threshold of sand by orders of magnitude. We examine a global dataset of river channel geometry and show that the shear stress range for sand-bedded channels is entirely within the range of entrainment thresholds for sand-mud mixtures - suggesting that rivers that suspend their sandy bed material are still threshold rivers in terms of bank material. We then present new findings from a New Jersey coastal-plain river examining if and how river-bank toe composition controls hydraulic geometry. We consider the toe because it is the foundation of the river bank, and its erosion leads to channel widening. Along a 20-km profile of the river we measure cross-section geometry, bed slope, and bed and bank composition, and we explore multiple methods of measuring the threshold shear stress of the the river-bank toe in-situ. As the composition of the river bed transitions from gravel to sand, we see preliminary evidence of a shift from bed-threshold to bank-threshold control on hydraulic geometry. We also observe that sub-bankfull flows are insufficient to erode (cohesive) bank materials, even though transport of sand is active at nearly all flows. Our findings highlight the importance of focusing on river-bank toe material, which in the studied stream is always submerged. The toe is more compacted and more resistant to erosion than the subaerially-exposed upper bank. We find mounting evidence that sand-bedded rivers are much like gravel-bedded river; they are near-threshold channels in which the suspended load does not play a controlling role in the determination of equilibrium hydraulic geometry.
Kresch, D.L.; Laenen, Antonius
1984-01-01
Failure of the debris dam, blocking the outflow of Spirit Lake near Mount St. Helens, could result in a mudflow down the Toutle and Cowlitz Rivers into the Columbia River. Flood elevations at the Trojan Nuclear Power Plant on the Columbia River, 5 mi upstream from the Cowlitz River, were simulated with a hydraulic routing model. The simulations are made for four Columbia River discharges in each of two scenarios, one in which Columbia River floods coincide with a mudflow and the other in which Columbia River floods follow a mudflow sediment deposit upstream from the Cowlitz River. In the first scenario, Manning 's roughness coefficients for clear water and for mudflow in the Columbia River are used; in the second scenario only clear water coefficients are used. The grade elevation at the power plant is 45 ft above sea level. The simulated elevations exceed 44 ft if the mudflow coincides with a Columbia River discharge that has a recurrence interval greater than 10 years (610,000 cu ft/sec); the mudflow is assumed to extend downstream from the Cowlitz River to the mouth of the Columbia River, and Manning 's roughness coefficients for a mudflow are used. The simulated elevation is 32 ft if the mudflow coincides with a 100-yr flood (820,000 cu ft/sec) and clear-water Manning 's coefficients are used throughout the entire reach of the Columbia River. The elevations exceed 45 ft if a flow exceeding the 2-yr peak discharge in the Columbia River (410,000 cu ft/sec) follows the deposit of 0.5 billion cu yd of mudflow sediment upstream of the Cowlitz River before there has been any appreciable scour or dredging of the deposit. In this simulation it is assumed that: (1) the top of the sediment deposited in the Columbia River is at an elevation of 30 ft at the mouth of the Cowlitz River, (2) the surface elevation of the sediment deposit decreases in an upstream direction at a rate of 2.5 ft/mi, and (3) clear water Manning 's coefficients apply to the entire modeled reach of the Columbia River. (Author 's abstract)
Leake, Stanley A.; Owen-Joyce, Sandra J.; Heilman, Julian A.
2013-01-01
Water use along the lower Colorado River is allocated as “consumptive use,” which is defined to be the amount of water diverted from the river minus the amount that returns to the river. Diversions of water from the river include surface water in canals and water removed from the river by pumping wells in the aquifer connected to the river. A complication in accounting for water pumped by wells occurs if the pumping depletes water in drains and reduces measured return flow in those drains. In that case, consumptive use of water pumped by the wells is accounted for in the reduction of measured return flow. A method is needed to understand where groundwater pumping will deplete water in the river and where it will deplete water in drains. To provide a basis for future accounting for pumped groundwater in the Parker-Palo Verde-Cibola area, a superposition model was constructed. The model consists of three layers of finite-difference cells that cover most of the aquifer in the study area. The model was run repeatedly with each run having a pumping well in a different model cell. The source of pumped water that is depletion of the river, expressed as a fraction of the pumping rate, was computed for all active cells in model layer 1, and maps were constructed to understand where groundwater pumping depletes the river and where it depletes drains. The model results indicate that if one or more drains exist between a pumping well location and the river, nearly all of the depletion will be from drains, and little or no depletion will come from the Colorado River. Results also show that if a well pumps on a side of the river with no drains in the immediate area, depletion will come from the Colorado River. Finally, if a well pumps between the river and drains that parallel the river, a fraction of the pumping will come from the river and the rest will come from the drains. Model results presented in this report may be considered in development or refinement of strategies for accounting for groundwater pumping in the river aquifer connected to the Colorado River in the study area.
Downstream on the Mississippi.
ERIC Educational Resources Information Center
Parfit, Michael
1993-01-01
Recounts a trip down the Lower Mississippi River starting in Memphis, describing the features of the river at different stops along the way. Aspects of life along the river discussed include the levee system built to contain the waters, flooding on the river, and travel on the river. (MDH)
WATER QUALITY EFFECTS OF HYPORHEIC PROCESSING IN A LARGE RIVER
Water quality changes along hyporheic flow paths may have
important effects on river water quality and aquatic habitat. Previous
studies on the Willamette River, Oregon, showed that river water follows
hyporheic flow paths through highly porous deposits created by river...
DOE Office of Scientific and Technical Information (OSTI.GOV)
A.G. Crook Company; United States. Bonneville Power Administration
1993-07-01
This report presents data for monthly mean streamflows adjusted for storage change, evaporation, and irrigation, for the years 1928-1990, for the Colorado River Basin, the Missouri River Basin, the Peace River Basin, and the Slave River Basin.
Eight river principles for navigating the science–policy interface
Scientists and policymakers often work together to develop policy about the sustainable use of river ecosystems. River science plays an important role in developing river policy but how can key aspects of river science be conveyed as a heuristic to navigate the interface between ...
Code of Federal Regulations, 2010 CFR
2010-07-01
..., its territories and possessions: (1) Volume I, Atlantic Coast, from St. Croix River, Maine, to Shrewsbury River, New Jersey. (2) Volume II, Atlantic Coast, from Shrewsbury River, New Jersey, to Little River, South Carolina. (3) Volume III, Atlantic and Gulf Coasts, from Little River, South Carolina, to...
Dissolved-oxygen and algal conditions in selected locations of the Willamette River basin, Oregon
Rinella, F.A.; McKenzie, S.W.; Wille, S.A.
1981-01-01
During July and August 1978, the U.S. Geological Survey, in cooperation with the Oregon Department of Enviromental Quality, made three intensive river-quality dissolved-oxygen studies in the upper Willamette River basin. Two studies were made on the upper Willamette River and one was made on the Santiam River, a Willamette River tributary. Nitrification, occurring in both the upper Willamette and South Santiam Rivers, accounted for about 62% and 92% of the DO sag in the rivers, respectively. Rates of nitrification were found to be dependent on ammonia concentrations in the rivers. Periphyton and phytoplankton algal samples were collected on the main stem Willamette River and selected tributaries during August 1978. Diatoms were the dominant group in both the periphyton and phytoplankton samples. The most common diatom genera were Melosira, Stephanodiscus, Cymbella, Achnanthes, and Nitzschia. Comparisons with historical data indicate no significant difference from previous years in the total abundance or diversity of the algae. (USGS)
Tillman, Fred D.
2015-01-01
The Colorado River and its tributaries supply water to more than 35 million people in the United States and 3 million people in Mexico, irrigating more than 4.5 million acres of farmland, and generating about 12 billion kilowatt hours of hydroelectric power annually. The Upper Colorado River Basin, encompassing more than 110,000 square miles (mi2), contains the headwaters of the Colorado River (also known as the River) and is an important source of snowmelt runoff to the River. Groundwater discharge also is an important source of water in the River and its tributaries, with estimates ranging from 21 to 58 percent of streamflow in the upper basin. Planning for the sustainable management of the Colorado River in future climates requires an understanding of the Upper Colorado River Basin groundwater system. This report documents input datasets for a Soil-Water Balance groundwater recharge model that was developed for the Upper Colorado River Basin.
Broshears, R.E.; Clark, G.M.; Jobson, H.E.
2001-01-01
Stream discharge and the transport of nitrate, atrazine, and metolachlor in the Mississippi River Basin were simulated using the DAFLOW/BLTM hydrologic model. The simulated domain for stream discharge included river reaches downstream from the following stations in the National Stream Quality Accounting Network: Mississippi River at Clinton, IA; Missouri River at Hermann, MO: Ohio River at Grand Chain, IL: And Arkansas River at Little Rock, AR. Coefficients of hydraulic geometry were calibrated using data from water year 1996; the model was validated by favourable simulation of observed discharges in water years 1992-1994. The transport of nitrate, atrazine, and metolachlor was simulated downstream from the Mississippi River at Thebes, IL, and the Ohio River at Grand Chain. Simulated concentrations compared favourably with observed concentrations at Baton Rouge, LA. Development of this model is a preliminary step in gaining a more quantitative understanding of the sources and fate of nutrients and pesticides delivered from the Mississippi River Basin to the Gulf of Mexico.
Modeling water quality, temperature, and flow in Link River, south-central Oregon
Sullivan, Annett B.; Rounds, Stewart A.
2016-09-09
The 2.1-km (1.3-mi) Link River connects Upper Klamath Lake to the Klamath River in south-central Oregon. A CE-QUAL-W2 flow and water-quality model of Link River was developed to provide a connection between an existing model of the upper Klamath River and any existing or future models of Upper Klamath Lake. Water-quality sampling at six locations in Link River was done during 2013–15 to support model development and to provide a better understanding of instream biogeochemical processes. The short reach and high velocities in Link River resulted in fast travel times and limited water-quality transformations, except for dissolved oxygen. Reaeration through the reach, especially at the falls in Link River, was particularly important in moderating dissolved oxygen concentrations that at times entered the reach at Link River Dam with marked supersaturation or subsaturation. This reaeration resulted in concentrations closer to saturation downstream at the mouth of Link River.
NASA Astrophysics Data System (ADS)
Ward, A. S.; Schmadel, N.; Wondzell, S. M.
2017-12-01
River networks are broadly recognized to expand and contract in response to hydrologic forcing. Additionally, the individual controls on river corridor dynamics of hydrologic forcing and geologic setting are well recognized. However, we currently lack tools to integrate our understanding of process dynamics in the river corridor and make predictions at the scale of river networks. In this study, we develop a perceptual model of the river corridor in mountain river networks, translate this into a reduced-complexity mechanistic model, and implement the model in a well-studied headwater catchment. We found that the river network was most sensitive to hydrologic dynamics under the lowest discharges (Qgauge < 1 L s-1). We also demonstrate a discharge-dependence on the dominant controls on network expansion, contraction, and river corridor exchange. Finally, we suggest this parsimonious model will be useful to managers of water resources who need to estimate connectivity and flow initiation location along the river corridor over broad, unstudied catchments.
River flow modeling using artificial neural networks in Kapuas river, West Kalimantan, Indonesia
NASA Astrophysics Data System (ADS)
Herawati, Henny; Suripin, Suharyanto
2017-11-01
Kapuas River is located in the province of West Kalimantan. Kapuas river length is 1,086 km and river basin areas about 100,000 Km2. The availability of river flow data in the Long River and very wide catchments are difficult to obtain, while river flow data are essential for planning waterworks. To predict the water flow in the catchment area requires a lot of hydrology coefficient, so it is very difficult to predict and obtain results that closer to the real conditions. This paper demonstrates that artificial neural network (ANN) could be used to predict the water flow. The ANN technique can be used to predict the incidence of water discharge that occurs in the Kapuas River based on rainfall and evaporation data. With the data available to do training on the artificial neural network model is obtained mean square error (MSE) 0.00007. The river flow predictions could be carried out after the training. The results showed differences in water discharge measurement and prediction of about 4%.
A survey of whitewater recreation impacts along five West Virginia rivers
Leung, Y.-F.; Marion, J.L.
1998-01-01
Results are reported from an assessment of whitewater river recreation impacts at river accesses and recreation sites along five West Virginia rivers: the New, Gauley, Cheat, Tygart, and Shenandoah. Procedures were developed and applied to assess resource conditions on 24 river access roads, 68 river accesses, and 151 recreation sites. The majority of river accesses and recreation sites are located on the New and Gauley rivers, which account for most of the state?s whitewater recreation use. Site conditions are variable. While some river accesses and sites are situated on resistant rocky substrates, many are poorly designed and/or located on erodible soil and sand substrates. Recreation site sizes and other areal measures of site disturbance are quite large, coincident with the large group sizes associated with commercially outfitted whitewater rafting trips. Recommendations are offered for managing river accesses and sites and whitewater visitation and the selection of indicators and standards as part of a Limits of Acceptable Change management process. Procedures and recommendations for continued visitor impact monitoring are also offered.
Backwater effects in the Amazon River basin of Brazil
Meade, R.H.; Rayol, J.M.; Da Conceicao, S.C.; Natividade, J.R.G.
1991-01-01
The Amazon River mainstem of Brazil is so regulated by differences in the timing of tributary inputs and by seasonal storage of water on floodplains that maximum discharges exceed minimum discharges by a factor of only 3. Large tributaries that drain the southern Amazon River basin reach their peak discharges two months earlier than does the mainstem. The resulting backwater in the lowermost 800 km of two large southern tributaries, the Madeira and Puru??s rivers, causes falling river stages to be as much as 2-3 m higher than rising stages at any given discharge. Large tributaries that drain the northernmost Amazon River basin reach their annual minimum discharges three to four months later than does the mainstem. In the lowermost 300-400 km of the Negro River, the largest northern tributary and the fifth largest river in the world, the lowest stages of the year correspond to those of the Amazon River mainstem rather than to those in the upstream reaches of the Negro River. ?? 1991 Springer-Verlag New York Inc.
Hupp, C.R.
2000-01-01
Rivers fed by glaciers constitute a major part of the freshwater runoff into the Cook Inlet basin of south-central Alaska. This basin is very important to the economy of the State of Alaska because it is home to more than half of the population and it supports multi-million dollar commercial, subsistence and sport fisheries. Hence an understanding of how glacial runoff influences biological productivity is important for managing rivers that drain into Cook Inlet. This paper examines the ways in which the regulation of glacier-fed rivers by proglacial lakes affects salmon productivity, with particular reference to the Kenai River. Salmon escapement per unit channel length on the Kenai River is between two and ten times that found for rain-and-snowmelt dominated rivers and glacier-fed rivers lacking lake regulation. Lakes are shown to influence biological processes in glacier-fed rivers by attenuating peak flows, sustaining high flows throughout the summer, supplementing winter low flows, settling suspended sediment, and increasing river temperatures. Downstream from large lakes, glacier-fed rivers are less disturbed, channels are relatively stable and have well-developed salmonid habitats. The positive influences are indicated by the high diversity and abundances of benthic macroinvertebrates, which are important food resources for juvenile salmonids. High summer flows allow access for up-river salmon runs and lakes also provide both overwintering and rearing habitat. Copyright ?? 2000 John Wiley & Sons, Ltd.Rivers fed by glaciers constitute a major part of the freshwater runoff into the Cook Inlet basin of south-central Alaska. This basin is very important to the economy of the State of Alaska because it is home to more than half of the population and it supports multi-million dollar commercial, subsistence and sport fisheries. Hence an understanding of how glacial runoff influences biological productivity is important for managing rivers that drain into Cook Inlet. This paper examines the ways in which the regulation of glacier-fed rivers by proglacial lakes affects salmon productivity, with particular reference to the Kenai River. Salmon escapement per unit channel length on the Kenai River is between two and ten times that found for rain-and-snowmelt dominated rivers and glacier-fed rivers lacking lake regulation. Lakes are shown to influence biological processes in glacier-fed rivers by attenuating peak flows, sustaining high flows throughout the summer, supplementing winter low flows, settling suspended sediment, and increasing river temperatures. Downstream from large lakes, glacier-fed rivers are less disturbed, channels are relatively stable and have well-developed salmonid habitats. The positive influences are indicated by the high diversity and abundances of benthic macroinvertebrates, which are important food resources for juvenile salmonids. High summer flows allow access for up-river salmon runs and lakes also provide both overwintering and rearing habitat.
Terrebonne Parish-Wide Forced Drainage System, Terrebonne Parish, Louisiana.
1983-08-01
Gibson, Louisiana show Bayou Lafourche deposits at the surface capping Red River deposits, in turn overlying Teche Mississippi levees. There are five...eastern side of the alluvial *valley. Following the diversion of the Mississippi River from the Teche channel, the Red River continued to flow within...the Mississippi River and Red River . These alluvial sediments were left by the distributary streams of several deltas of the Mississippi River . The
Lower Charles River Bathymetry: 108 Years of Fresh Water
NASA Astrophysics Data System (ADS)
Yoder, M.; Sacarny, M.
2017-12-01
The Lower Charles River is a heavily utilized urban river that runs between Cambridge and Boston in Massachusetts. The recreational usage of the river is dependent on adequate water depths, but there have been no definitive prior studies on the sedimentation rate of the Lower Charles River. The river transitioned from tidal to a freshwater basin in 1908 due to the construction of the (old) Charles River Dam. Water surface height on the Lower Charles River is maintained within ±1 foot through controlled discharge at the new Charles River Dam. The current study area for historical comparisons is from the old Charles River Dam to the Boston University Bridge. This study conducted a bathymetric survey of the Lower Charles River, digitized three prior surveys in the study area, calculated volumes and depth distributions for each survey, and estimated sedimentation rates from fits to the volumes over time. The oldest chart digitized was produced in 1902 during dam construction deliberations. The average sedimentation rate is estimated as 5-10 mm/year, which implies 1.8-3.5 feet sedimentation since 1908. Sedimentation rates and distributions are necessary to develop comprehensive management plans for the river and there is evidence to suggest that sedimentation rates in the shallow upstream areas are higher than the inferred rates in the study area.
Hamad, Samera Hussein; Schauer, James Jay; Shafer, Martin Merrill; Abed Al-Raheem, Esam; Satar, Hyder
2012-01-01
The distribution of dissolved and particulate forms of 49 elements was investigated along transect of the Tigris River (one of the major rivers of the world) within Baghdad city and in its major tributary (Diyala River) from 11 to 28 July 2011. SF-ICP-MS was used to measure total and filterable elements at 17 locations along the Tigris River transect, two samples from the Diyala River, and in one sample from the confluence of the two rivers. The calculated particulate forms were used to determine the particle-partition coefficients of the metals. No major changes in the elements concentrations down the river transect. Dissolved phases dominated the physical speciation of many metals (e.g., As, Mo, and Pt) in the Tigris River, while Al, Fe, Pb, Th, and Ti were exhibiting high particulate fractions, with a trend of particle partition coefficients of [Ti(40) > Th(35) > Fe(15) > Al(13) > Pb(4.5)] ∗ 106 L/kg. Particulate forms of all metals exhibited high concentrations in the Diyala River, though the partition coefficients were low due to high TSS (~270 mg/L). A comparison of Tigris with the major rivers of the world showed that Tigris quality in Baghdad is comparable to Seine River quality in Paris. PMID:23304083
River-corridor habitat dynamics, Lower Missouri River
Jacobson, Robert B.
2010-01-01
Intensive management of the Missouri River for navigation, flood control, and power generation has resulted in substantial physical changes to the river corridor. Historically, the Missouri River was characterized by a shifting, multithread channel and abundant unvegetated sandbars. The shifting channel provided a wide variety of hydraulic environments and large areas of connected and unconnected off-channel water bodies.Beginning in the early 1800s and continuing to the present, the channel of the Lower Missouri River (downstream from Sioux City, Iowa) has been trained into a fast, deep, single-thread channel to stabilize banks and maintain commercial navigation. Wing dikes now concentrate the flow, and revetments and levees keep the channel in place and disconnect it from the flood plain. In addition, reservoir regulation of the Missouri River upstream of Yankton, South Dakota, has substantially changed the annual hydrograph, sediment loads, temperature regime, and nutrient budgets.While changes to the Missouri River have resulted in broad social and economic benefits, they have also been associated with loss of river-corridor habitats and diminished populations of native fish and wildlife species. Today, Missouri River stakeholders are seeking ways to restore some natural ecosystem benefits of the Lower Missouri River without compromising traditional economic uses of the river and flood plain.
Kircher, J.E.
1981-01-01
Sediment samples were collected on the South Platte, North Platte, and Platte Rivers in Colorado and Nebraska during the 1979 and 1980 runoff seasons. Suspended-sediment concentrations ranged from 62 to 3,705 milligrams per liter and the maximum load was 45,547 metric tons per day. The percentage of suspended sediment samller than sand (less than 0.062 millimeter) was as follows: 23 to 78 percent for the South Platte River, 9 to 30 percent for the North Platte River, and 2 to 89 percent for the Platte River. Bedload-transport rates ranged from 0.0085 to 0.67 kilogram per second per meter of channel width for the entire study area. The median grain size of bedload ranged from 0.6 to 2.6 millimeters for the South Platte River, 0.5 to 0.8 millimeter for the North Platte River, and 0.6 to 1.2 millimeters for th Platte River. The median grain size of bed material for the South Platte River ranged from 0.3 to 2.4 millimeters, compared to 0.5 to 0.9 millimeter for the North Platte River, and 0.4 to 3.1 millimeters for the Platte River. (USGS)
Chloride control and monitoring program in the Wichita River Basin, Texas, 1996-2009
Haynie, M.M.; Burke, G.F.; Baldys, Stanley
2011-01-01
Water resources of the Wichita River Basin in north-central Texas are vital to the water users in Wichita Falls, Tex., and surrounding areas. The Wichita River Basin includes three major forks of the Wichita River upstream from Lake Kemp, approximately 50 miles southwest of Wichita Falls, Tex. The main stem of the Wichita River is formed by the confluence of the North Wichita River and Middle Fork Wichita River upstream from Truscott Brine Lake. The confluence of the South Wichita River with the Wichita River is northwest of Seymour, Tex. (fig. 1). Waters from the Wichita River Basin, which is part of the Red River Basin, are characterized by high concentrations of chloride and other salinity-related constituents from salt springs and seeps (hereinafter salt springs) in the upper reaches of the basin. These salt springs have their origins in the Permian Period when the Texas Panhandle and western Oklahoma areas were covered by a broad shallow sea. Over geologic time, evaporation of the shallow seas resulted in the formation of salt deposits, which today are part of the geologic formations underlying the area. Groundwater in these formations is characterized by high chloride concentrations from these salt deposits, and some of this groundwater is discharged by the salt springs into the Wichita River.
Breck, S.W.; Wilson, K.R.; Andersen, D.C.
2003-01-01
We compared beaver (Castor canadensis) foraging patterns on Fremont cottonwood (Populus deltoides subsp. wislizenii) saplings and the probability of saplings being cut on a 10 km reach of the flow-regulated Green River and a 8.6 km reach of the free-flowing Yampa River in northwestern Colorado. We measured the abundance and density of cottonwood on each reach and followed the fates of individually marked saplings in three patches of cottonwood on the Yampa River and two patches on the Green River. Two natural floods on the Yampa River and one controlled flood on the Green River between May 1998 and November 1999 allowed us to assess the effect of flooding on beaver herbivory. Independent of beaver herbivory, flow regulation on the Green River has caused a decrease in number of cottonwood patches per kilometre of river, area of patches per kilometre, and average stem density within cottonwood patches. The number of saplings cut per beaver colony was three times lower on the Green River than on the Yampa River but the probability of a sapling being cut by a beaver was still higher on the Green River because of lower sapling density there. Controlled flooding appeared to increase the rate of foraging on the Green River by inundating patches of cottonwood, which enhanced access by beaver. Our results suggest regulation can magnify the impact of beaver on cottonwood through interrelated effects on plant spatial distribution and cottonwood density, with the result that beaver herbivory will need to be considered in plans to enhance cottonwood populations along regulated rivers.
Riverine based eco-tourism: Trinity River non-market benefits estimates
Douglas, A.J.; Taylor, J.G.
1998-01-01
California's Central Valley Project (CVP) was approved by voters in a statewide referendum in 1933. CVP referendum approval initiated funding for construction of important water development projects that had far reaching effects on regional water supplies. The construction of Trinity Dam in 1963 and the subsequent transbasin diversion of Trinity River flow was one of several CVP projects that had noteworthy adverse environmental and regional economic impacts. The Trinity River is the largest tributary of the Klamath River, and has its headwaters in the Trinity Alps of north-central California. After the construction of Trinity Dam in 1963, 90% of the Trinity River flow at Lewiston was moved to the Sacramento River via the Clear Creek Tunnel. Before 1963, the Trinity River was a major recreation resource of Northern California. The loss of streamflow has had a marked adverse impact on Trinity River-related recreation activities and the size and robustness of Trinity River salmon, steelhead, shad, and sturgeon runs. Trinity River water produces hydropower during its transit via Bureau of Reclamation canals and pumps to the northern San Joaquin Valley, where it is used for irrigated agriculture. The benefits provided by Trinity River instream flow-related environmental amenities were estimated with the travel cost method (TCM). Trinity River non-market benefits are about $406 million per annum, while the social cost of sending water down the Trinity River ranges from $17 to $42 million per annum, depending on the exact flow. We also discuss the relative magnitude of Trinity River survey data contingent value method (CVM) benefits estimates.
NASA Astrophysics Data System (ADS)
Lininger, K. B.; Wohl, E.; Rose, J. R.
2018-03-01
Floodplains accumulate and store organic carbon (OC) and release OC to rivers, but studies of floodplain soil OC come from small rivers or small spatial extents on larger rivers in temperate latitudes. Warming climate is causing substantial change in geomorphic process and OC fluxes in high latitude rivers. We investigate geomorphic controls on floodplain soil OC concentrations in active-layer mineral sediment in the Yukon Flats, interior Alaska. We characterize OC along the Yukon River and four tributaries in relation to geomorphic controls at the river basin, segment, and reach scales. Average OC concentration within floodplain soil is 2.8% (median = 2.2%). Statistical analyses indicate that OC varies among river basins, among planform types along a river depending on the geomorphic unit, and among geomorphic units. OC decreases with sample depth, suggesting that most OC accumulates via autochthonous inputs from floodplain vegetation. Floodplain and river characteristics, such as grain size, soil moisture, planform, migration rate, and riverine DOC concentrations, likely influence differences among rivers. Grain size, soil moisture, and age of surface likely influence differences among geomorphic units. Mean OC concentrations vary more among geomorphic units (wetlands = 5.1% versus bars = 2.0%) than among study rivers (Dall River = 3.8% versus Teedrinjik River = 2.3%), suggesting that reach-scale geomorphic processes more strongly control the spatial distribution of OC than basin-scale processes. Investigating differences at the basin and reach scale is necessary to accurately assess the amount and distribution of floodplain soil OC, as well as the geomorphic controls on OC.
Anderson, Elizabeth P.; Pringle, Catherine M.; Freeman, Mary C.
2008-01-01
Costa Rica has recently experienced a rapid proliferation of dams for hydropower on rivers draining its northern Caribbean slope. In the Sarapiquí River Basin, eight hydropower plants were built between 1990 and 1999 and more projects are either under construction or proposed. The majority of these dams are small (<15 m tall) and operate as water diversion projects.While the potential environmental effects of individual projects are evaluated prior to dam construction, there is a need for consideration of the basin-scale ecological consequences of hydropower development. This study was a first attempt to quantify the extent of river fragmentation by dams in the Sarapiquí River Basin.Using simple spatial analyses, the length of river upstream from dams and the length of de-watered reaches downstream from dams was measured. Results indicated that there are currently 306.8 km of river (9.4% of the network) upstream from eight existing dams in the Sarapiquí River Basin and 30.6 km of rivers (0.9% of the network) with significantly reduced flow downstream from dams. Rivers upstream from dams primarily drain two life zones: Premontane Rain Forest (107.9 km) and Lower Montane Rain Forest (168.2 km).Simple spatial analyses can be used as a predictive or planning tool for considering the effects of future dams in a basin-scale context. In the Sarapiquí River Basin, we recommend that future dam projects be constructed on already dammed rivers to minimize additional river fragmentation and to protect remaining riverine connectivity.
Modeling a three-dimensional river plume over continental shelf using a 3D unstructured grid model
Cheng, R.T.; Casulli, V.; ,
2004-01-01
River derived fresh water discharging into an adjacent continental shelf forms a trapped river plume that propagates in a narrow region along the coast. These river plumes are real and they have been observed in the field. Many previous investigations have reported some aspects of the river plume properties, which are sensitive to stratification, Coriolis acceleration, winds (upwelling or downwelling), coastal currents, and river discharge. Numerical modeling of the dynamics of river plumes is very challenging, because the complete problem involves a wide range of vertical and horizontal scales. Proper simulations of river plume dynamics cannot be achieved without a realistic representation of the flow and salinity structure near the river mouth that controls the initial formation and propagation of the plume in the coastal ocean. In this study, an unstructured grid model was used for simulations of river plume dynamics allowing fine grid resolution in the river and in regions near the coast with a coarse grid in the far field of the river plume in the coastal ocean, in the vertical, fine fixed levels were used near the free surface, and coarse vertical levels were used over the continental shelf. The simulations have demonstrated the uniquely important role played by Coriolis acceleration. Without Coriolis acceleration, no trapped river plume can be formed no matter how favorable the ambient conditions might be. The simulation results show properties of the river plume and the characteristics of flow and salinity within the estuary; they are completely consistent with the physics of estuaries and coastal oceans.
NASA Technical Reports Server (NTRS)
DelCastillo, Carlos E.; Miller, Richard L.
2007-01-01
We investigated the use of ocean color remote sensing to measure transport of dissolved organic carbon (DOC) by the Mississippi River to the Gulf of Mexico. From 2000 to 2005 we recorded surface measurements of DOC, colored dissolved organic matter (CDOM), salinity, and water-leaving radiances during five cruises to the Mississippi River Plume. These measurements were used to develop empirical relationships to derive CDOM, DOC, and salinity from monthly composites of SeaWiFS imagery collected from 1998 through 2005. We used river flow data and a two-end-member mixing model to derive DOC concentrations in the river end-member, river flow, and DOC transport using remote sensing data. We compared our remote sensing estimates of river flow and DOC transport with data collected by the United States Geological Survey (USGS) from 1998 through 2005. Our remote sensing estimates of river flow and DOC transport correlated well (r2 0.70) with the USGS data. Our remote sensing estimates and USGS field data showed low variability in DOC concentrations in the river end-member (7-11%), and high seasonal variability in river flow (50%). Therefore, changes in river flow control the variability in DOC transport, indicating that the remote sensing estimate of river flow is the most critical element of our DOC transport measurement. We concluded that it is possible to use this method to estimate DOC transport by other large rivers if there are data on the relationship between CDOM, DOC, and salinity in the river plume.
Estimation of global plastic loads delivered by rivers into the sea
NASA Astrophysics Data System (ADS)
Schmidt, Christian; Krauth, Tobias; Klöckner, Phillipp; Römer, Melina-Sophie; Stier, Britta; Reemtsma, Thorsten; Wagner, Stephan
2017-04-01
A considerable fraction of marine plastic debris likely originates from land-based sources. Transport of plastics by rivers is a potential mechanism that connects plastic debris generated on land with the marine environment. We analyze existing and experimental data of plastic loads in rivers and relate these to the amount of mismanaged plastic waste (MMPW) generated in the river catchments. We find a positive relationship between the plastic load in rivers and the amount of MMPW. Using our empirical MMPW-plastic river load-relationship we estimated the annual plastic load for 1494 rivers, ranging from small first order streams to large rivers, which have an outlet to the sea. We estimate that the global load of plastic debris delivered by rivers to the sea is 39000 tons per year with a large 95% prediction interval between 247 tons per year and 16.7 million tons per year, respectively. Our best estimate is considerably lower than the estimated total land-based inputs which range between 4.8-12.7 million tons anually (Jambeck et al. 2015). Approximately 75% of the total load is transported by the 10 top-ranked rivers which are predominantly located in Asia. These river catchments encompass countries with a large population and high economic growth but an insufficient waste infrastructure. Reducing the plastic loads in these rivers by 50% would reduce the global inputs by 37%. Of the total MMPW generated within river catchments, only a small fraction of about 0.05 % has been found to be mobile in rivers. Thus, either only a small fraction of MMPW enters the river systems, or a substantial fraction of plastic debris accumulates in river systems world wide. References: Jambeck, J. R., R. Geyer, C. Wilcox, T. R. Siegler, M. Perryman, A. Andrady, R. Narayan, and K. L. Law (2015), Plastic waste inputs from land into the ocean, Science, 347(6223), 768-771, doi:10.1126/science.1260352.
Wilson, Richard P.; Owen-Joyce, Sandra J.
1994-01-01
Accounting for the use of Colorado River water is required by the U.S. Supreme Court decree, 1964, Arizona v. California. Water pumped from wells on the flood plain and from certain wells on alluvial slopes outside the flood plain is presumed to be river water and is accounted for as Colorado River water. A method was developed to identify wells outside the f1ood plain of the lower Colorado River that yield water that will be replaced by water from the river. The method provides a uniform criterion of identification for all users pumping water from wells. Wells that have a static water-level elevation equal to or below the accounting surface are presumed to yield water that will be replaced by water from the river. Wells that have a static water-level elevation above the accounting surface are presumed to yield water that will be replaced by water from precipitation and inflow from tributary valleys. The method is based on the concept of a river aquifer and an accounting surface within the river aquifer. The river aquifer consists of permeable, partly saturated sediments and sedimentary rocks that are hydraulically connected to the Colorado River so that water can move between the river and the aquifer in response to withdrawal of water from the aquifer or differences in water-level elevations between the river and the aquifer. The accounting surface represents the elevation and slope of the unconfined static water table in the river aquifer outside the flood plain and reservoirs that would exist if the river were the only source of water to the river aquifer. Maps at a scale of 1:100,000 show the extent and elevation of the accounting surface from the area surrounding Lake Mead to Laguna Dam near Yuma, Arizona.
Ellsworth, Craig M.; VanderKooi, Scott P.
2011-01-01
The Chiloquin Dam was located at river kilometer (rkm) 1.3 on the Sprague River near the town of Chiloquin, Oregon. The dam was identified as a barrier that potentially inhibited or prevented the upstream spawning migrations and other movements of endangered Lost River suckers (Deltistes luxatus), shortnose suckers (Chasmistes brevirostris), and other fish in the Sprague River. Our research objectives in 2009 were to evaluate adult catostomid spawning migration patterns using radio telemetry to identify and describe shifts in spawning area distribution and migration behavior following the removal of Chiloquin Dam in 2008. We attached external radio transmitters to 58 Lost River suckers and 59 shortnose suckers captured at the Williamson River fish weir. A total of 17 radio-tagged Lost River suckers and one radio-tagged shortnose sucker were detected approaching the site of the former Chiloquin Dam but only two radio-tagged fish (one male Lost River sucker and one female Lost River sucker) were detected crossing upstream of the dam site. A lower proportion of radio-tagged shortnose suckers were detected migrating into the Sprague River when compared with previous years. Detections on remote passive integrated transponder (PIT) tag arrays located in the Sprague River show that although the proportion of fish coming into the Sprague River is small when compared to the number of fish crossing the Williamson River fish weir, the number of fish migrating upstream of the Chiloquin Dam site increased exponentially in the first year since its removal. These data will be used in conjunction with larval production and adult spawning distribution data to evaluate the effectiveness of dam removal in order to provide increased access to underutilized spawning habitat located further upstream in the Sprague River and to reduce the crowding of spawning fish below the dam site.
The Columbia River--on the Leading Edge
NASA Astrophysics Data System (ADS)
O'Connor, J. E.
2005-05-01
On the leading edge of the North American plate, the Columbia River is the largest of the world's 40 or so rivers with drainage areas greater than 500,000 square kilometers to drain toward a convergent plate boundary. This unique setting results in a unique continental river basin; marked by episodic and cataclysmic geologic disturbance, but also famously fecund with perhaps 10 to 16 million salmon historically spawning in its waters each year. Now transformed by dams, transportation infrastructure, dikes and diversions, the Columbia River presents an expensive conundrum for management of its many values. Inclusion of river ecology and geomorphology in discussions of river management is generally limited to observations of the last 200 years-a time period of little natural disturbance and low sediment transport. However, consideration of longer timescales provides additional perspective of historical ecologic and geomorphic conditions. Only 230 km from its mouth, the Columbia River bisects the volcanic arc of the Cascade Range, forming the Columbia River Gorge. Cenozoic lava flows have blocked the river, forcing diversions and new canyon cutting. Holocene eruptions of Mount Mazama (Crater Lake), Mount Hood, Mount St. Helens, and Mount Rainier have shed immense quantities of sediment into the lower Columbia River, forming a large percentage of the Holocene sediment transported through the lower river. Quaternary landslides, perhaps triggered by great earthquakes, have descended from the 1000-m-high gorge walls, also blocking and diverting the river, one as recently as 550 years ago. These geologic disturbances, mostly outside the realm of historical observation and operating at timescales of 100s to 1000s of years in the gorge and elsewhere, have clearly affected basin geomorphology, riverine ecology, and past and present cultural utilization of river resources. The historic productivity of the river, however, hints at extraordinary resilience (and perhaps dependence) of the Columbia River system to such disturbances, many of which are similar to engineered disturbances of the last 200 years.
NASA Astrophysics Data System (ADS)
Ding, Hu; Liu, Cong-Qiang; Zhao, Zhi-Qi; Li, Si-Liang; Lang, Yun-Chao; Li, Xiao-Dong; Hu, Jian; Liu, Bao-Jian
2017-05-01
This study focuses on the chemical and Sr isotopic compositions of the dissolved load of the rivers in the Liao River basin, which is one of the principal river systems in northeast China. Water samples were collected from both the tributaries and the main channel of the Liao River, Daling River and Hun-Tai River. Chemical and isotopic analyses indicated that four major reservoirs (carbonates (+gypsum), silicates, evaporites and anthropogenic inputs) contribute to the total dissolved solutes. Other than carbonate (+gypsum) weathering, anthropogenic inputs provide the majority of the solutes in the river water. The estimated chemical weathering rates (as TDS) of silicate, carbonate (+gypsum) and evaporites are 0.28, 3.12 and 0.75 t/km2/yr for the main stream of the Liao River and 7.01, 25.0 and 2.80 t/km2/yr for the Daliao River, respectively. The associated CO2 consumption rates by silicate weathering and carbonate (+gypsum) weathering are 10.1 and 9.94 × 103 mol/km2/yr in the main stream of the Liao River and 69.0 and 80.4 × 103 mol/km2/yr in the Hun-Tai River, respectively. The Daling River basin has the highest silicate weathering rate (TDSsil, 3.84 t/km2/yr), and the Hun-Tai River has the highest carbonate weathering rate (TDScarb, 25.0 t/km2/yr). The Raoyang River, with an anthropogenic cation input fraction of up to 49%, has the lowest chemical weathering rates, which indicates that human impact is not a negligible parameter when studying the chemical weathering of these rivers. Both short-term and long-term study of riverine dissolved loads are needed to a better understanding of the chemical weathering and controlling factors.
Influence of urban area on the water quality of the Campo River basin, Paraná State, Brazil.
Carvalho, K Q; Lima, S B; Passig, F H; Gusmão, L K; Souza, D C; Kreutz, C; Belini, A D; Arantes, E J
2015-12-01
The Campo River basin is located on the third plateau of the Paraná State or trap plateau of Paraná, at the middle portion between the rivers Ivaí and Piquiri, southern Brazil, between the coordinates 23° 53 and 24° 10' South Latitude and 52° 15' and 52° 31' West Longitude. The basin has 384 Km² area, being 247 km² in the municipality of Campo Mourão and 137 km² in the municipality of Peabiru, in Paraná State. The Campo River is a left bank tributary of the Mourão River, which flows into the Ivaí River. The objective of this study was to monitor water quality in the Km 119 River and the Campo River, tributaries of the Mourão River, with monthly collection of water samples to determine pH, temperature, turbidity, biochemical oxygen demand, dissolved oxygen, fecal coliforms, total solids, total nitrogen, ammoniacal nitrogen, nitrite, nitrate and total phosphorus. The results obtained were compared with the indices established by the environmental legislation and applied in the determination of the Water Quality Index (WQI) used by the Water Institute of Paraná State, regulating environmental agency. Poor water quality in these rivers presents a worrying scenario for the region, since this river is the main source of water supply for the public system. Results of organic matter, fecal coliforms and total phosphorus were higher than the limits established by Resolution CONAMA 357/2005 to river class 2, specially at downstream of the Km 119 River and the Campo River, due to the significant influence of the urban anthropic activity by the lack of tertiary treatment and also rural by the lack of basic sanitation in this area. Results of WQI of Km 119 River and do Campo River indicated that water quality can be classified as average in 71% and good in 29% of the sites evaluated.
Araújo, Cristiano V M; Griffith, Daniel M; Vera-Vera, Victoria; Jentzsch, Paul Vargas; Cervera, Laura; Nieto-Ariza, Beatriz; Salvatierra, David; Erazo, Santiago; Jaramillo, Rusbel; Ramos, Luis A; Moreira-Santos, Matilde; Ribeiro, Rui
2018-04-01
Aquatic ecotoxicity assays used to assess ecological risk assume that organisms living in a contaminated habitat are forcedly exposed to the contamination. This assumption neglects the ability of organisms to detect and avoid contamination by moving towards less disturbed habitats, as long as connectivity exists. In fluvial systems, many environmental parameters vary spatially and thus condition organisms' habitat selection. We assessed the preference of zebra fish (Danio rerio) when exposed to water samples from two western Ecuadorian rivers with apparently distinct disturbance levels: Pescadillo River (highly disturbed) and Oro River (moderately disturbed). Using a non-forced exposure system in which water samples from each river were arranged according to their spatial sequence in the field and connected to allow individuals to move freely among samples, we assayed habitat selection by D. rerio to assess environmental disturbance in the two rivers. Fish exposed to Pescadillo River samples preferred downstream samples near the confluence zone with the Oro River. Fish exposed to Oro River samples preferred upstream waters. When exposed to samples from both rivers simultaneously, fish exhibited the same pattern of habitat selection by preferring the Oro River samples. Given that the rivers are connected, preference for the Oro River enabled us to predict a depression in fish populations in the Pescadillo River. Although these findings indicate higher disturbance levels in the Pescadillo River, none of the physical-chemical variables measured was significantly correlated with the preference pattern towards the Oro River. Non-linear spatial patterns of habitat preference suggest that other environmental parameters like urban or agricultural contaminants play an important role in the model organism's habitat selection in these rivers. The non-forced exposure system represents a habitat selection-based approach that can serve as a valuable tool to unravel the factors that dictate organisms' spatial distribution in connected ecosystems. Copyright © 2017 Elsevier B.V. All rights reserved.
Depositional settings of sand beaches along whitewater rivers
Vincent, K.R.; Andrews, E.D.
2008-01-01
The numbers and sizes of sand beaches suitable for recreation along selected whitewater rivers in the western United States depend on sand concentrations, range of discharge and the size, frequency and type of depositional settings. River-width expansions downstream from constrictions are the predominant depositional setting for sand beaches in the upper Grand Canyon and along five Wild and Scenic Rivers in Idaho, but not along other rivers. Beaches located upstream from constrictions are rare, in general, except in the Grand Canyon. Beaches found in expansions without constrictions dominate depositional sites along the Yampa and Green Rivers, are fairly common along the rivers in Idaho, but are relatively rare in the Grand Canyon. The magnitude of flow expansion is a reliable predictor of beach size. Beaches located on the inside of curves are uncommon, in general, but can be important recreation sites. The mid-channel bar setting is the least important from a recreation standpoint because that setting is rare and beaches there are typically small, and emergent only at low flow. The frequency of beaches is highly variable among rivers and the concentration of sand in transport is only partially responsible. Of the rivers studied, the unregulated Yampa River carries the highest concentrations of suspended sand and has among the most beaches (1.2 beaches km-1). Emergent sand beaches are essentially nonexistent along the Deschutes River and are rare along other Oregon rivers, yet these rivers transport some sand. Sand beaches are fairly common (0.8-1.1 beaches km-1) along the regulated Colorado River, but are comparatively rare (0.6 beaches km-1) along the unregulated Middle Fork Salmon River. The suspended sand concentrations in study reaches of these two rivers are similar, and the difference in the frequency of beaches may be largely because the processes that create beach-deposition settings are less active along the Middle Fork Salmon.
Communicating River Level Data and Information to Stakeholders with Different Interests
NASA Astrophysics Data System (ADS)
Macleod, K.; Sripada, S.; Ioris, A.; Arts, K.; van der Wal, R.
2012-12-01
There is a need to increase the effectiveness of how river level data are communicated to a range of stakeholders with an interest in river level information to increase the use of data collected by regulatory agencies. Currently, river level data is provided to members of the public through a web site without any formal engagement with river users having taken place. In our research project called wikiRivers, we are working with the suppliers of river level data as well as the users of this data to explore and improve from the user perspective how river level data and information is made available online. We are focusing on the application of natural language generation technology to create textual summaries of river level data tailored for specific interest groups. These tailored textual summaries will be presented among other modes of information presentation (e.g. maps and visualizations) with the aim to increase communication effectiveness. Natural language generation involves developing computational models that use non-linguistic input data to produce natural language as their output. Acquiring accurate correct system knowledge for natural language generation is a key step in developing such an effective computer software system. In this paper we set out the needs for this project based on discussions with the stakeholder who supplies the river level data and current cyberinfrastructure and report on what we have learned from those individuals and groups who use river level data. Stages in the wikiRivers stakeholder identification, engagement and cyberinfrastructure development. S1- interviews with collectors and suppliers of river level data. S2- river level data stakeholder analysis, including analysis of their interests in individual river networks in Scotland and what they require from the cyberinfrastructure. S3-5 Iterative development and testing of cyberinfrastructure and modelling of river level data with domain and stakeholder knowledge.
77 FR 55466 - Barren River Lake Hydro LLC; Notice Soliciting Scoping Comments
Federal Register 2010, 2011, 2012, 2013, 2014
2012-09-10
... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Project No. 13022-003] Barren River Lake Hydro LLC; Notice Soliciting Scoping Comments Take notice that the following hydroelectric..., 2012. d. Applicant: Barren River Lake Hydro LLC (Barren River Hydro). e. Name of Project: Barren River...
NASA Astrophysics Data System (ADS)
Pan, Feifei; Wang, Cheng; Xi, Xiaohuan
2016-09-01
Remote sensing from satellites and airborne platforms provides valuable data for monitoring and gauging river discharge. One effective approach first estimates river stage from satellite-measured inundation area based on the inundation area-river stage relationship (IARSR), and then the estimated river stage is used to compute river discharge based on the stage-discharge rating (SDR) curve. However, this approach is difficult to implement because of a lack of data for constructing the SDR curves. This study proposes a new method to construct the SDR curves using remotely sensed river cross-sectional inundation areas and river bathymetry. The proposed method was tested over a river reach between two USGS gauging stations, i.e., Kingston Mines (KM) and Copperas Creek (CC) along the Illinois River. First a polygon over each of two cross sections was defined. A complete IARSR curve was constructed inside each polygon using digital elevation model (DEM) and river bathymetric data. The constructed IARSR curves were then used to estimate 47 river water surface elevations at each cross section based on 47 river inundation areas estimated from Landsat TM images collected during 1994-2002. The estimated water surface elevations were substituted into an objective function formed by the Bernoulli equation of gradually varied open channel flow. A nonlinear global optimization scheme was applied to solve the Manning's coefficient through minimizing the objective function value. Finally the SDR curve was constructed at the KM site using the solved Manning's coefficient, channel cross sectional geometry and the Manning's equation, and employed to estimate river discharges. The root mean square error (RMSE) in the estimated river discharges against the USGS measured river discharges is 112.4 m3/s. To consider the variation of the Manning's coefficient in the vertical direction, this study also suggested a power-law function to describe the vertical decline of the Manning's coefficient with the water level from the channel bed lowest elevation to the bank-full level. The constructed SDR curve with the vertical variation of the Manning's coefficient reduced the RMSE in the estimated river discharges to 83.9 m3/s. These results indicate that the method developed and tested in this study is effective and robust, and has the potential for improving our ability of remote sensing of river discharge and providing data for water resources management, global water cycle study, and flood forecasting and prevention.
Hinck, Jo Ellen; Blazer, Vicki; Denslow, Nancy D.; Echols, Kathy R.; Gale, Robert W.; May, Tom W.; Claunch, Rachael; Wieser, Carla; Anderson, Patrick J.; Coyle, James J.; Gross, Timothy S.; Tillitt, Donald E.
2007-01-01
Largemouth bass (Micropterus salmoides) and common carp (Cyprinus carpio) were collected from 13 sites in 4 river basins in the southeastern United States to document spatial trends in accumulative contaminants, health indicators, and reproductive biomarkers. Organochlorine residues, 2,3,7,8- tetrachlorodibenzo-p-dioxin-like activity (TCDD-EQ), and elemental contaminants were measured in composite samples of whole fish, grouped by species and gender, from each site. Fish were field-examined for external and internal anomalies, selected organs were weighed to compute somatic indices, and tissue and fluid samples were preserved for fish health and reproductive biomarker analyses. Mercury concentrations in bass samples from all sites exceeded toxicity thresholds for mammals [>0.1 micrograms per gram wet weight (ug/g ww)], fish (>0.2 ug/g ww), and birds (>0.3 ug/g ww) and were greatest (>0.5 ug/g ww) in samples from the Alabama River at Eureka Landing, Alabama; the Mobile River at Bucks, Alabama; the Apalachicola River at Blountstown, Florida; the Savannah River at Sylvania, Georgia; and the Pee Dee River at Bucksport, South Carolina. Selenium concentrations were relatively high (>0.75 ug/g ww) in fish from the Tombigbee River at Lavaca, Alabama; the Mobile River at Bucks; and the Chattahoochee River at Omaha, Georgia compared to those from other sites. Concentrations of 2,2-bis (p-chlorophenyl)- 1,1-dichloroethylene (p,p'-DDE) were high in fish from the Chattahoochee River at Omaha and the Mobile River near Bucks, which was near a 2,2-bis (p-chlorophenyl)-1,1- dichloroethylene (DDT) formulating facility that historically discharged into the lower Mobile River. Toxaphene concentrations in fish from the Flint River near Albany, Georgia (60-100 nanograms per gram (ng/g) ww) may pose a risk to fish. Concentrations of other formerly used (total chlordanes, dieldrin, endrin, aldrin, mirex, and hexachlorobenzene) and currently used (pentachlorobenzene, pentachloroanisole, dacthal, endosulfan, y-HCH, and methoxychlor) organochlorine residues generally were low or did not exceed toxicity thresholds. Total polychlorinated biphenyls concentrations in samples from the Coosa River at Childersburg, Alabama; the Apalachicola River at Omaha; the Apalachicola River at Blountstown; and the Pee Dee River at Bucksport were >480 ng/g ww and may be a risk to piscivorous wildlife. Dioxin-like activity as measured by TCDD-EQ was greatest [>10 picograms per gram (pg/g)] in male fish from the Coosa River at Childersburg and the Mobile River at Bucks. Hepatic ethoxyresorufin O-deethylase activity generally was greatest in carp from the Mobile River Basin [means >10 picomols per minute per milligram of protein (pmol/min/mg)] and in bass from the Tombigbee River at Lavaca and Pee Dee River at Pee Dee, South Carolina (means >65 pmol/min/mg). Altered biomarkers were noted in fish from all basins. The field necropsy and histopathological examination determined that fish from the Mobile River Basin generally were in poorer health than those from the other basins. In bass, health assessment index scores were correlated with mercury and p,p'-DDE concentrations. High health assessment index scores in Mobile River Basin fish were widespread and caused primarily by parasitic infestations, which were most severe in fish from the Tombigbee River at Lavaca and the Alabama River at Eureka Landing. Tumors were present in few fish (n = 5; 0.01%). Ovarian tumors of the same origin (smooth muscle) were present in two older carp from the Chattahoochee River near Omaha, Georgia and may be contaminant related. Reproductive biomarkers including gonadosomatic index, vitellogenin concentrations, and steroid hormone concentrations were anomalous in fish from various sites but were not consistently related to any particular chemical contaminant. Intersex gonads were identified in 47 male bass (42%) representing 12 sites and may indicate exposure to endocrine disrupting comp
Life history and status of Shortnose Sturgeon (Acipenser brevirostrum LeSueur, 1818)
Kynard, Boyd; Bolden, Stephania; Kieffer, Micah; Collins, Mark; Brundage, Hal; Hilton, Eric; Litvak, Mark; Kinnison, Michael T.; King, Timothy L.; Peterson, Douglas C.
2016-01-01
Shortnose Sturgeon = SNS (Acipenser brevirostrum) is a small diadromous species with most populations living in large Atlantic coast rivers and estuaries of North America from New Brunswick, Canada, to GA, USA. There are no naturally landlocked populations, so all populations require access to fresh water and salt water to complete a natural life cycle. The species is amphidromous with use of fresh water and salt water (the estuary) varied across the species range, a pattern that may reflect whether freshwater or saltwater habitats provide optimal foraging and growth conditions. Migration is a dominant behavior during life history, beginning when fish are hatchling free embryos (southern SNS) or larvae (northeastern and far northern SNS). Migration continues by juveniles and nonspawning adult life stages on an individual time schedule with fish moving between natal river and estuary to forage or seek refuge, and by spawning adults migrating to and from riverine spawning grounds. Coastal movements by adults throughout the range (but particularly in the Gulf of Maine = GOM and among southern rivers) suggest widespread foraging, refuge use, and widespread colonization of new rivers. Colonization may also be occurring in the Potomac River, MD–VA–DC (midAtlantic region). Genetic studies (mtDNA and nDNA) identified distinct individual river populations of SNS, and recent rangewide nDNA studies identified five distinct evolutionary lineages of SNS in the USA: a northern metapopulation in GOM rivers; the Connecticut River; the Hudson River; a Delaware River–Chesapeake Bay metapopulation; and a large southern metapopulation (SC rivers to Altamaha River, GA). The Saint John River, NB, Canada, in the Bay of Fundy (north of the GOM), is the sixth distinct genetic lineage within SNS. Life history information from telemetry tracking supports the genetic information documenting extensive movement of adults among rivers within the three metapopulations. However, individual river populations with spawning adults are still the best basal unit for management and recovery planning. The focus on individual river populations should be complemented with attention to migratory processes and corridors that foster metapopulation level risks and benefits. The species may be extirpated at the center of the range, i.e., the midAtlantic region (Chesapeake Bay, MD–VA, and probably, NC), but large rivers in VA, including the James and Potomac rivers, need study. The largest SNS populations in GOM and northeastern rivers, like the Kennebec, Hudson, and Delaware rivers, typically have tens of thousands of adults. This contrasts with southern rivers, where rivers typically have much fewer (6000 adults). River damming in the 19th and 20th Centuries extirpated some populations, and also, created two dysfunctional segmented populations: the Connecticut River SNS in CT–MA and the SanteeCooper rivers–Lake Marion SNS in SC. The major anthropogenic impact on SNS in marine waters is fisheries bycatch. The major impacts that determine annual recruitment success occur in freshwater firstly, where adult spawning migrations and spawning are blocked or spawning success is affected by river regulation and secondly, where poor survival of early life stages is caused by river dredging, pollution, and unregulated impingement/entrainment in water withdrawal facilities. Climate warming has the potential to reduce abundance or eliminate SNS in many rivers, particularly in the South. In 1998, the National Marine Fisheries Service (NMFS) recommended management of 19 rivers as distinct population segments (DPSs) based on strong fidelity to natal rivers. A Biological Assessment completed in 2010 reaffirmed this approach. NMFS has not formally listed DPSs under the ESA and the species remains listed as endangered rangewide in the USA.
NASA Astrophysics Data System (ADS)
Dorsey, Rebecca J.; O'Connell, Brennan; McDougall, Kristin; Homan, Mindy B.
2018-01-01
The Colorado River in the southwestern U.S. provides an excellent natural laboratory for studying the origins of a continent-scale river system, because deposits that formed prior to and during river initiation are well exposed in the lower river valley and nearby basinal sink. This paper presents a synthesis of regional stratigraphy, sedimentology, and micropaleontology from the southern Bouse Formation and similar-age deposits in the western Salton Trough, which we use to interpret processes that controlled the birth and early evolution of the Colorado River. The southern Bouse Formation is divided into three laterally persistent members: basal carbonate, siliciclastic, and upper bioclastic members. Basal carbonate accumulated in a tide-dominated marine embayment during a rise of relative sea level between 6.3 and 5.4 Ma, prior to arrival of the Colorado River. The transition to green claystone records initial rapid influx of river water and its distal clay wash load into the subtidal marine embayment at 5.4-5.3 Ma. This was followed by rapid southward progradation of the Colorado River delta, establishment of the earliest through-flowing river, and deposition of river-derived turbidites in the western Salton Trough (Wind Caves paleocanyon) between 5.3 and 5.1 Ma. Early delta progradation was followed by regional shut-down of river sand output between 5.1 and 4.8 Ma that resulted in deposition of marine clay in the Salton Trough, retreat of the delta, and re-flooding of the lower river valley by shallow marine water that deposited the Bouse upper bioclastic member. Resumption of sediment discharge at 4.8 Ma drove massive progradation of fluvial-deltaic deposits back down the river valley into the northern Gulf and Salton Trough. These results provide evidence for a discontinuous, start-stop-start history of sand output during initiation of the Colorado River that is not predicted by existing models for this system. The underlying controls on punctuated sediment discharge are assessed by comparing the depositional chronology to the record of global sea-level change. The lower Colorado River Valley and Salton Trough experienced marine transgression during a gradual fall in global sea level between 6.3 and 5.5 Ma, implicating tectonic subsidence as the main driver of latest Miocene relative sea-level rise. A major fall of global sea level at 5.3 Ma outpaced subsidence and drove regional delta progradation, earliest flushing of Colorado River sand into the northern Gulf of California, and erosion of Bouse basal carbonate and siliciclastic members. The lower Colorado River valley was re-flooded by shallow marine waters during smaller changes in global sea level 5.1-4.8 Ma, after the river first ran through it, which requires a mechanism to stop delivery of sand to the lower river valley. We propose that tectonically controlled subsidence along the lower Colorado River, upstream of the southern Bouse study area, temporarily trapped sediment and stopped delivery of sand to the lower river valley and northern Gulf of California for 200-300 kyr. Massive progradation of the fluvial-deltaic system back down the river valley into the Salton Trough starting 4.8-4.5 Ma apparently was driven by a huge increase in sediment discharge that overwhelmed the sediment-storage capacity of sub-basins along the lower river corridor and established the fully integrated river channel network. Accompanies Dorsey et al. "Punctuated sediment discharge during early Pliocene birth of the Colorado River: Evidence from regional stratigraphy, sedimentology, and paleontology". Accompanies Dorsey et al. "Punctuated sediment discharge during early Pliocene birth of the Colorado River: Evidence from regional stratigraphy, sedimentology, and paleontology". Accompanies Dorsey et al. "Punctuated sediment discharge during early Pliocene birth of the Colorado River: Evidence from regional stratigraphy, sedimentology, and paleontology".
Thiros, Susan A.
2017-03-23
The U.S. Geological Survey (USGS), in cooperation with the Colorado River Basin Salinity Control Forum, studied trends in dissolved-solids loads at selected sites in and near the Uinta Basin, Utah. The Uinta Basin study area includes the Duchesne River Basin and the Middle Green River Basin in Utah from below Flaming Gorge Reservoir to the town of Green River.Annual dissolved-solids loads for water years (WY) 1989 through 2013 were estimated for 16 gaging stations in the study area using streamflow and water-quality data from the USGS National Water Information System database. Eight gaging stations that monitored catchments with limited or no agricultural land use (natural subbasins) were used to assess loads from natural sources. Four gaging stations that monitored catchments with agricultural land in the Duchesne River Basin were used to assess loads from agricultural sources. Four other gaging stations were included in the dissolved-solids load and trend analysis to help assess the effects of agricultural areas that drain to the Green River in the Uinta Basin, but outside of the Duchesne River Basin.Estimated mean annual dissolved-solids loads for WY 1989–2013 ranged from 1,520 tons at Lake Fork River above Moon Lake, near Mountain Home, Utah (UT), to 1,760,000 tons at Green River near Green River, UT. The flow-normalized loads at gaging stations upstream of agricultural activities showed no trend or a relatively small change. The largest net change in modeled flow-normalized load was -352,000 tons (a 17.8-percent decrease) at Green River near Green River, UT.Annual streamflow and modeled dissolved-solids loads at the gaging stations were balanced between upstream and downstream sites to determine how much water and dissolved solids were transported to the Duchesne River and a section of the Green River, and how much was picked up in each drainage area. Mass-balance calculations of WY 1989–2013 mean annual dissolved-solids loads at the studied sites show that Green River near Jensen, UT, accounts for 64 percent of the load in the river at Green River, UT, while the Duchesne River and White River contribute 10 and 13 percent, respectively.Annual streamflow and modeled dissolved-solids loads at the gaging stations were balanced between upstream and downstream sites to determine how much water and dissolved solids were transported to the Duchesne River and a section of the Green River, and how much was picked up in each drainage area. Mass-balance calculations of WY 1989–2013 mean annual dissolved-solids loads at the studied sites show that Green River near Jensen, UT, accounts for 64 percent of the load in the river at Green River, UT, while the Duchesne River and White River contribute 10 and 13 percent, respectively.The flow-normalized dissolved-solids loads estimated at Duchesne River near Randlett, UT, and White River near Watson, UT, decreased by 68,000 and 55,300 tons, or 27.8 and 20.8 percent respectively, when comparing 1989 to 2013. The drainage basins for both rivers have undergone salinity-control projects since the early 1980s to reduce the dissolved-solids load entering the Colorado River. Approximately 19 percent of the net change in flow-normalized load at Green River at Green River, UT, is from changes in load modeled at Duchesne River near Randlett, UT, and 16 percent from changes in load modeled at White River near Watson, UT. The net change in flow-normalized load estimated at Green River near Greendale, UT, for WY 1989–2013 accounts for about 45 percent of the net change estimated at Green River at Green River, UT.Mass-balance calculations of WY 1989–2013 mean annual dissolved-solids loads at the studied sites in the Duchesne River Basin show that 75,400 tons or 44 percent of the load at the Duchesne River near Randlett, UT, gaging station was not accounted for at any of the upstream gages. Most of this unmonitored load is derived from tributary inflow, groundwater discharge, unconsumed irrigation water, and irrigation tail water.A mass balance of WY 1989–2013 flow-normalized loads estimated at sites in the Duchesne River Basin indicates that the flow-normalized load of unmonitored inflow to the Duchesne River between the Myton and Randlett gaging stations decreased by 38 percent. The total net decrease in flow-normalized load calculated for unmonitored inflow in the drainage basin accounts for 94 percent of the decrease in WY 1989–2013 flow-normalized load modeled at the Duchesne River near Randlett, UT, gaging station. Irrigation improvements in the drainage basin have likely contributed to the decrease in flow-normalized load.Reductions in dissolved-solids load estimated by the Natural Resources Conservation Service (NRCS) and the Bureau of Reclamation (Reclamation) from on- and off-farm improvements in the Uinta Basin totaled about 135,000 tons in 2013 (81,900 tons from on-farm improvements and 53,300 tons from off-farm improvements). The reduction in dissolved-solids load resulting from on- and off-farm improvements facilitated by the NRCS and Reclamation in the Price River Basin from 1989 to 2013 was estimated to be 64,800 tons.The amount of sprinkler-irrigated land mapped in the drainage area or subbasin area for a gaging station was used to estimate the reduction in load resulting from the conversion from flood to sprinkler irrigation. Sprinkler-irrigated land mapped in the Uinta Basin totaled 109,630 acres in 2012. Assuming conversion to wheel-line sprinklers, a reduction in dissolved-solids load in the Uinta Basin of 95,800 tons in 2012 was calculated using the sprinkler-irrigation acreage and a pre-salinity-control project dissolved-solids yield of 1.04 tons per acre.A reduction of 72,800 tons in dissolved-solids load from irrigation improvements was determined from sprinkler-irrigated lands in the Ashley Valley and Jensen, Pelican Lake, and Pleasant Valley areas (mapped in 2012); and in the Price River Basin (mapped in 2011). This decrease in dissolved-solids load is 8,800 tons more than the decrease in unmonitored flow-normalized dissolved-solids load (-64,000 tons) determined for the Green River between the Jensen and Green River gaging stations.The net WY 1989–2013 change in flow-normalized dissolved-solids load at the Duchesne River near Randlett, UT, and the Green River between the Jensen and Green River, UT, gaging stations determined from mass-balance calculations was compared to reported reductions in dissolved-solids load from on- and off-farm improvements and estimated reductions in load determined from mapped sprinkler-irrigated areas in the Duchesne River Basin and the area draining to the Green River between the Jensen and Green River gaging stations. The combined NRCS and Reclamation estimates of reduction in dissolved-solids load from on- and off-farm improvements in the study area (200,000 tons) is more than the reduction in load estimated using the acreage with sprinkler improvements (136,000 tons) or the mass-balance of flow-normalized load (132,000 tons).
29 CFR 1917.126 - River banks.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 29 Labor 7 2011-07-01 2011-07-01 false River banks. 1917.126 Section 1917.126 Labor Regulations...) MARINE TERMINALS Terminal Facilities § 1917.126 River banks. (a) This section applies to temporary installations or temporary operations near a river bank. (b) Where working surfaces at river banks slope so...
27 CFR 9.164 - River Junction.
Code of Federal Regulations, 2013 CFR
2013-04-01
..., follow the levee along the San Joaquin River onto the Ripon, CA quadrangle map; (3) Then in a northerly... River Junction. (a) Name. The name of the viticultural area described in this section is “River Junction..., CA 1969, photorevised 1980; (2) Vernalis, CA 1969, photorevised 1980. (c) Boundaries. The River...
27 CFR 9.164 - River Junction.
Code of Federal Regulations, 2012 CFR
2012-04-01
..., follow the levee along the San Joaquin River onto the Ripon, CA quadrangle map; (3) Then in a northerly... River Junction. (a) Name. The name of the viticultural area described in this section is “River Junction..., CA 1969, photorevised 1980; (2) Vernalis, CA 1969, photorevised 1980. (c) Boundaries. The River...
27 CFR 9.164 - River Junction.
Code of Federal Regulations, 2010 CFR
2010-04-01
..., follow the levee along the San Joaquin River onto the Ripon, CA quadrangle map; (3) Then in a northerly... River Junction. (a) Name. The name of the viticultural area described in this section is “River Junction..., CA 1969, photorevised 1980; (2) Vernalis, CA 1969, photorevised 1980. (c) Boundaries. The River...
27 CFR 9.164 - River Junction.
Code of Federal Regulations, 2011 CFR
2011-04-01
..., follow the levee along the San Joaquin River onto the Ripon, CA quadrangle map; (3) Then in a northerly... River Junction. (a) Name. The name of the viticultural area described in this section is “River Junction..., CA 1969, photorevised 1980; (2) Vernalis, CA 1969, photorevised 1980. (c) Boundaries. The River...
27 CFR 9.164 - River Junction.
Code of Federal Regulations, 2014 CFR
2014-04-01
..., follow the levee along the San Joaquin River onto the Ripon, CA quadrangle map; (3) Then in a northerly... River Junction. (a) Name. The name of the viticultural area described in this section is “River Junction..., CA 1969, photorevised 1980; (2) Vernalis, CA 1969, photorevised 1980. (c) Boundaries. The River...
40 CFR Appendix A to Part 97 - Final Section 126 Rule: EGU Allocations, 2004-2007
Code of Federal Regulations, 2012 CFR
2012-07-01
... VA POSSUM POINT 3804 4 528 VA POSSUM POINT 3804 5 322 VA POTOMAC RIVER 3788 1 203 VA POTOMAC RIVER 3788 2 139 VA POTOMAC RIVER 3788 3 232 VA POTOMAC RIVER 3788 4 223 VA POTOMAC RIVER 3788 5 222 VA SEI...
40 CFR Appendix A to Part 97 - Final Section 126 Rule: EGU Allocations, 2004-2007
Code of Federal Regulations, 2013 CFR
2013-07-01
... VA POSSUM POINT 3804 4 528 VA POSSUM POINT 3804 5 322 VA POTOMAC RIVER 3788 1 203 VA POTOMAC RIVER 3788 2 139 VA POTOMAC RIVER 3788 3 232 VA POTOMAC RIVER 3788 4 223 VA POTOMAC RIVER 3788 5 222 VA SEI...
40 CFR Appendix A to Part 97 - Final Section 126 Rule: EGU Allocations, 2004-2007
Code of Federal Regulations, 2014 CFR
2014-07-01
... VA POSSUM POINT 3804 4 528 VA POSSUM POINT 3804 5 322 VA POTOMAC RIVER 3788 1 203 VA POTOMAC RIVER 3788 2 139 VA POTOMAC RIVER 3788 3 232 VA POTOMAC RIVER 3788 4 223 VA POTOMAC RIVER 3788 5 222 VA SEI...
Earl C. Leatherberry; David W. Lime; Jerrilyn Lavarre Thompson
1980-01-01
Participation in river recreation has been expanding at a rapid rate. This paper reviews selected phenomenon associated with the growing popularity of rivers as recreational resources. The paper will: (1) describe the river recreation resource (the supply situation); (2) present selected indicators of increased river recreation use (the demand situation); (3) present...
ERIC Educational Resources Information Center
Koussouris, Theodore; And Others
1990-01-01
Presented is a survey of a river including physiochemical measurements and river fauna observations. It is shown that the self-purification gradient of river water quality and the possible ecological disturbances due to pollutants entering the river create an unpredictable pattern of recovery. (CW)
77 FR 30518 - Support of Deployment of Prototype Small Modular Reactors at the Savannah River Site
Federal Register 2010, 2011, 2012, 2013, 2014
2012-05-23
... DEPARTMENT OF ENERGY Support of Deployment of Prototype Small Modular Reactors at the Savannah River Site AGENCY: Savannah River Operations Office, Department of Energy (DOE). ACTION: Notice of availability. SUMMARY: DOE-Savannah River Operations Office (SR), in conjunction with the Savannah River...
ERIC Educational Resources Information Center
Turner, James S.
1991-01-01
Discusses "Always a River," a joint project of six midwestern state humanities councils that focuses on the Ohio River Valley's history, ecology, and development. Highlights exhibitions to be set up on a river barge that will tour Ohio River towns and cities during 1991. Stresses interrelationships between the river and the communities…
76 FR 8978 - Proposed Flood Elevation Determinations
Federal Register 2010, 2011, 2012, 2013, 2014
2011-02-16
... White River ted Areas effects from confluence of Taney White River). to County. approximate ly 685 feet upstream of the White River confluence Bee Creek From the None +698 Unincorpora (backwater White River ted Areas effects from confluence of Taney White River). to County. approximate ly 1,700 feet upstream of...
33 CFR 117.734 - Navesink River (Swimming River).
Code of Federal Regulations, 2010 CFR
2010-07-01
... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Navesink River (Swimming River). 117.734 Section 117.734 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY... (Swimming River). The Oceanic Bridge, mile 4.5, shall open on signal; except that, from December 1 through...
Habitat and Hydrology Condition Indices for the Upper Mississippi, Missouri, and Ohio Rivers
Habitat and hydrology indices were developed to assess the conditions in reaches of the impounded Upper Mississippi River, the Fort Peck and Garrison reaches of the Upper Missouri River, the Missouri National Recreational River, and the channelized Lower Missouri River, and the O...
2. SNAKE RIVER VALLEY IRRIGATION DISTRICT DAM, PHOTOGRAPHIC COPY OF ...
2. SNAKE RIVER VALLEY IRRIGATION DISTRICT DAM, PHOTOGRAPHIC COPY OF DRAWING, PLAN, SHEET 5 OF 5, 1924 (on file at the Idaho State Office of Water Resources, Boise, Idaho) - Snake River Valley Irrigation District, East Side of Snake River (River Mile 796), Shelley, Bingham County, ID
DETECTING FOREST STRESS AND DECLINE IN RESPONSE TO INCREASING RIVER FLOW IN SOUTHWEST FLORIDA, USA
Forest stress and decline resulting from increased river flows were investigated in Myakka River State Park (MRSP), Florida, USA. Since 1977, land-use changes around the upper Myakka River watershed have resulted in significant increases in water entering the river, which have...
29 CFR 1917.126 - River banks.
Code of Federal Regulations, 2010 CFR
2010-07-01
...) MARINE TERMINALS Terminal Facilities § 1917.126 River banks. (a) This section applies to temporary installations or temporary operations near a river bank. (b) Where working surfaces at river banks slope so... 29 Labor 7 2010-07-01 2010-07-01 false River banks. 1917.126 Section 1917.126 Labor Regulations...
RiverHeath: Neighborhood Loop Geothermal Exchange System
DOE Office of Scientific and Technical Information (OSTI.GOV)
Geall, Mark
2016-07-11
The goal of the RiverHeath project is to develop a geothermal exchange system at lower capital infrastructure cost than current geothermal exchange systems. The RiverHeath system features an innovative design that incorporates use of the adjacent river through river-based heat exchange plates. The flowing water provides a tremendous amount of heat transfer. As a result, the installation cost of this geothermal exchange system is lower than more traditional vertical bore systems. Many urban areas are located along rivers and other waterways. RiverHeath will serve as a template for other projects adjacent to the water.
High flow and riparian vegetation along the San Miguel River, Colorado
Friedman, J.M.; Auble, G.T.
2000-01-01
Riparian ecosystems are characterized by abundance of water and frequent flow related disturbance. River regulation typically decreases peak flows, reducing the amount of disturbance and altering the vegetation. The San Miguel River is one of the last relatively unregulated rivers remaining in the Colorado River Watershed. One goal of major landowners along the San Miguel including the Bureau of Land Management and The Nature Conservancy is to maintain their lands in a natural condition. Conservation of an entire river corridor requires an integrated understanding of the variability in ecosystems and external influences along the river. Therefore, the Bureau of Land Management and others have fostered a series of studies designed to catalogue that variability, and to characterize the processes that maintain the river as a whole. In addition to providing information useful to managers, these studies present a rare opportunity to investigate how a Colorado river operates in the absence of regulation.
Industrial pollution and the management of river water quality: a model of Kelani River, Sri Lanka.
Gunawardena, Asha; Wijeratne, E M S; White, Ben; Hailu, Atakelty; Pandit, Ram
2017-08-19
Water quality of the Kelani River has become a critical issue in Sri Lanka due to the high cost of maintaining drinking water standards and the market and non-market costs of deteriorating river ecosystem services. By integrating a catchment model with a river model of water quality, we developed a method to estimate the effect of pollution sources on ambient water quality. Using integrated model simulations, we estimate (1) the relative contribution from point (industrial and domestic) and non-point sources (river catchment) to river water quality and (2) pollutant transfer coefficients for zones along the lower section of the river. Transfer coefficients provide the basis for policy analyses in relation to the location of new industries and the setting of priorities for industrial pollution control. They also offer valuable information to design socially optimal economic policy to manage industrialized river catchments.
Butyltin compounds in River Otters (Lutra canadensis) from the Northwestern United States
Kannan, K.; Grove, Robert A.; Senthilkumar, K.; Henny, Charles J.; Geisy, J.P.
1999-01-01
Butyltin compounds, including mono-, di-, and tributyltin (MBT, DBT, and TBT) were measured in livers of 40 adult river otters (Lutra canadensis) collected from rivers and coastal bays in Washington and Oregon, USA. Butyltins were found in all the river otters, at a concentration range of 8.5a??2,610 ng/g, WW. The greatest concentration of total butyltins of 2,610 ng/g, WW, was found in a river otter collected in Puget Sound from Fort Ward, Washington. River otters collected near areas with major shipping activities, such as the Puget Sound, contained significantly greater concentrations (geometric mean: 367 ng/g, WW) of butyltins than those from rivers. Among butyltin compounds, MBT and DBT predominated in livers. The concentrations of butyltins in river otters ranged from comparable (Puget Sound) to less (rivers) than what was found in coastal cetaceans.
River meander modeling of the Wabash River near the Interstate 64 Bridge near Grayville, Illinois
Lant, Jeremiah G.; Boldt, Justin A.
2018-01-16
Natural river channels continually evolve and change shape over time. As a result, channel evolution or migration can cause problems for bridge structures that are fixed in the flood plain. A once-stable bridge structure that was uninfluenced by a river’s shape could be encroached upon by a migrating river channel. The potential effect of the actively meandering Wabash River on the Interstate 64 Bridge at the border with Indiana near Grayville, Illinois, was studied using a river migration model called RVR Meander. RVR Meander is a toolbox that can be used to model river channel meander migration with physically based bank erosion methods. This study assesses the Wabash River meandering processes through predictive modeling of natural meandering over the next 100 years, climate change effects through increased river flows, and bank protection measures near the Interstate 64 Bridge.
Water quality of Cisadane River based on watershed segmentation
NASA Astrophysics Data System (ADS)
Effendi, Hefni; Ayu Permatasari, Prita; Muslimah, Sri; Mursalin
2018-05-01
The growth of population and industrialization combined with land development along river cause water pollution and environmental deterioration. Cisadane River is one of the river in Indonesia where urbanization, industrialization, and agricultural are extremely main sources of pollution. Cisadane River is an interesting case for investigating the effect of land use to water quality and comparing water quality in every river segment. The main objectives with this study were to examine if there is a correlation between land use and water quality in Cisadane River and there is a difference in water quality between the upstream section of Cisadane River compared with its downstream section. This study compared water quality with land use condition in each segment of river. Land use classification showed that river segment that has more undeveloped area has better water quality compared to river segment with developed area. in general, BOD and COD values have increased from upstream to downstream. However, BOD and COD values do not show a steady increase in each segment Water quality is closely related to the surrounding land use.Therefore, it can not be concluded that the water quality downstream is worse than in the upstream area.
Regulation causes nitrogen cycling discontinuities in Mediterranean rivers.
von Schiller, Daniel; Aristi, Ibon; Ponsatí, Lídia; Arroita, Maite; Acuña, Vicenç; Elosegi, Arturo; Sabater, Sergi
2016-01-01
River regulation has fundamentally altered large sections of the world's river networks. The effects of dams on the structural properties of downstream reaches are well documented, but less is known about their effect on river ecosystem processes. We investigated the effect of dams on river nutrient cycling by comparing net uptake of total dissolved nitrogen (TDN), phosphorus (TDP) and organic carbon (DOC) in river reaches located upstream and downstream from three reservoir systems in the Ebro River basin (NE Iberian Peninsula). Increased hydromorphological stability, organic matter standing stocks and ecosystem metabolism below dams enhanced the whole-reach net uptake of TDN, but not that of TDP or DOC. Upstream from dams, river reaches tended to be at biogeochemical equilibrium (uptake≈release) for all nutrients, whereas river reaches below dams acted as net sinks of TDN. Overall, our results suggest that flow regulation by dams may cause relevant N cycling discontinuities in rivers. Higher net N uptake capacity below dams could lead to reduced N export to downstream ecosystems. Incorporating these discontinuities could significantly improve predictive models of N cycling and transport in complex river networks. Copyright © 2015. Published by Elsevier B.V.
Hydrologic alteration affects aquatic plant assemblages in an arid-land river
Vinson, Mark; Hestmark, Bennett; Barkworth, Mary E.
2014-01-01
We evaluated the effects of long-term flow alteration on primary-producer assemblages. In 1962, Flaming Gorge Dam was constructed on the Green River. The Yampa River has remained an unregulated hydrologically variable river that joins the Green River 100 km downstream from Flaming Gorge Dam. In the 1960s before dam construction only sparse occurrences of two macroalgae, Cladophora and Chara, and no submerged vascular plants were recorded in the Green and Yampa rivers. In 2009–2010, aquatic plants were abundant and widespread in the Green River from the dam downstream to the confluence with the Yampa River. The assemblage consisted of six vascular species, Elodea canadensis, Myriophyllum sibiricum, Nasturtium officinale,Potamogeton crispus, Potamogeton pectinatus, and Ranunculus aquatilis, the macroalgae Chara and Cladophora, and the bryophyte, Amblystegium riparium. In the Green River downstream from the Yampa River, and in the Yampa River, only sparse patches of Chara and Cladophora growing in the splash zone on boulders were collected. We attribute the observed changes in the Green River to an increase in water transparency and a reduction in suspended and bed-load sediment and high flow disturbances. The lack of hydrophyte colonization downstream from the confluence with the Yampa River has implications for understanding tributary amelioration of dam effects and for designing more natural flow-regime schedules downstream from large dams.
Attributes of an alluvial river and their relation to water policy and management
Trush, William J.; McBain, Scott M.; Leopold, Luna B.
2000-01-01
Rivers around the world are being regulated by dams to accommodate the needs of a rapidly growing global population. These regulatory efforts usually oppose the natural tendency of rivers to flood, move sediment, and migrate. Although an economic benefit, river regulation has come at unforeseen and unevaluated cumulative ecological costs. Historic and contemporary approaches to remedy environmental losses have largely ignored hydrologic, geomorphic, and biotic processes that form and maintain healthy alluvial river ecosystems. Several commonly known concepts that govern how alluvial channels work have been compiled into a set of “attributes” for alluvial river integrity. These attributes provide a minimum checklist of critical geomorphic and ecological processes derived from field observation and experimentation, a set of hypotheses to chart and evaluate strategies for restoring and preserving alluvial river ecosystems. They can guide how to (i) restore alluvial processes below an existing dam without necessarily resorting to extreme measures such as demolishing one, and (ii) preserve alluvial river integrity below proposed dams. Once altered by dam construction, a regulated alluvial river will never function as before. But a scaled-down morphology could retain much of a river's original integrity if key processes addressed in the attributes are explicitly provided. Although such a restoration strategy is an experiment, it may be the most practical solution for recovering regulated alluvial river ecosystems and the species that inhabit them. Preservation or restoration of the alluvial river attributes is a logical policy direction for river management in the future. PMID:11050220
Baldys, Stanley; Schalla, Frank E.
2012-01-01
Streamflow was measured at 66 sites from June 6–9, 2010, and at 68 sites from October 16–19, 2010, to identify reaches in the upper Brazos River Basin that were gaining or losing streamflow. Gaining reaches were identified in each of the five subbasins. The gaining reach in the Salt Fork Brazos River Basin began at USGS streamflow-gaging station 08080940 Salt Fork Brazos River at State Highway 208 near Clairemont, Tex. (site SF–6), upstream from where Duck Creek flows into the Salt Fork Brazos River and continued downstream past USGS streamflow-gaging station 08082000 Salt Fork Brazos River near Aspermont, Tex. (site SF–9), to the outlet of the basin. In the Double Mountain Fork Brazos River Basin, a gaining reach from near Post, Tex., downstream to the outlet of the basin was identified. Two gaining reaches were identified in the Clear Fork Brazos River Basin—one from near Roby, Tex., downstream to near Noodle, Tex., and second from Hawley, Tex., downstream to Nugent, Tex. Most of the North Bosque River was characterized as gaining streamflow. Streamflow gains were identified in the main stem of the Brazos River from where the Brazos River main stem forms at the confluence of the Salt Fork Brazos River and Double Mountain Fork Brazos River near Knox City, Tex., downstream to near Seymour, Tex.
Wilson, Richard P.; Owen-Joyce, Sandra J.
2002-01-01
During a period of sustained base-flow conditions in the Bill Williams River below Alamo Dam in west central Arizona from March to July 2000, the channel of the river through Planet Valley was dry, and the water table sloped almost due west parallel to the main slope of the flood plain. Water from the river infiltrated into the channel bottom at the head of Planet Valley, moved downgradient in the subsurface, and reappeared in the channel about 0.3 mile downstream from the east boundary of the Bill Williams River National Wildlife Refuge. A river aquifer in hydraulic connection with the Bill Williams River was mapped from a point 6.3 miles upstream from Highway 95 to the upstream end of Planet Valley. Formations that make up the river aquifer in Planet Valley are younger alluvium, older alluviums, and fanglomerate. Total thickness of the river aquifer probably is less than 200 feet in the bedrock canyons to as much as 1,035 feet in Planet Valley. The purpose of this study was to investigate the current hydrologic conditions along the Bill Williams River, which included an inventory of wells within the river aquifer of the Colorado River and in Planet Valley, and to determine the configuration of the water table. A map shows the elevation and configuration of the water table from the east end of Planet Valley to the confluence of the Bill Williams River with Lake Havasu.
NASA Astrophysics Data System (ADS)
Guo, Leicheng; Su, Ni; Zhu, Chunyan; He, Qing
2018-05-01
Streamflow and sediment loads undergo remarkable changes in worldwide rivers in response to climatic changes and human interferences. Understanding their variability and the causes is of vital importance regarding river management. With respect to the Changjiang River (CJR), one of the largest river systems on earth, we provide a comprehensive overview of its hydrological regime changes by analyzing long time series of river discharges and sediment loads data at multiple gauge stations in the basin downstream of Three Gorges Dam (TGD). We find profound river discharge reduction during flood peaks and in the wet-to-dry transition period, and slightly increased discharges in the dry season. Sediment loads have reduced progressively since 1980s owing to sediment yield reduction and dams in the upper basin, with notably accelerated reduction since the start of TGD operation in 2003. Channel degradation occurs in downstream river, leading to considerable river stage drop. Lowered river stages have caused a 'draining effect' on lakes by fostering lake outflows following TGD impoundments. The altered river-lake interplay hastens low water occurrence inside the lakes which can worsen the drought given shrinking lake sizes in long-term. Moreover, lake sedimentation has decreased since 2002 with less sediment trapped in and more sediment flushed out of the lakes. These hydrological changes have broad impacts on river flood and drought occurrences, water security, fluvial ecosystem, and delta safety.
River as a part of ground battlefield
NASA Astrophysics Data System (ADS)
Vračar, Miodrag S.; Pokrajac, Ivan; Okiljević, Predrag
2013-05-01
The rivers are in some circumstances part of the ground battlefield. Microseisms induced at the riverbed or ground at the river surrounding might be consequence of military activities (military ground transports, explosions, troop's activities, etc). Vibrations of those fluid-solid structures are modeled in terms of solid displacement and change of fluid pressure. This time varying fluid pressure in river, which originates from ground microseisms, is possible to detect with hydrophones. Therefore, hydroacoustic measurements in rivers enables detecting, identification and localization various types of military noisy activities at the ground as and those, which origin is in the river water (hydrodynamics of water flow, wind, waves, river vessels, etc). In this paper are presented river ambient noise measurements of the three great rivers: the Danube, the Sava and the Tisa, which flows in north part of Serbia in purpose to establish limits in detection of the ground vibrations in relatively wide frequency range from zero to 20 kHz. To confirm statement that the river is a part of ground battlefield, and that hydroacoustic noise is possible to use in detecting and analyzing ground microseisms induced by civil or military activities, some previous collected data of hydroacoustic noise measurement in the rivers are used. The data of the river ambient noise include noise induced by civil engineering activities, that ordinary take place in large cities, noise that produced ships and ambient noise of the river when human activities are significantly reduced. The poly spectral method was used in analysis such events.
Hunt, Charles B.
1969-01-01
John Wesley Powell clearly recognized that the spectacular features of the Colorado River - its many grand canyons - were dependent upon the structural history of the mountainous barriers crossed by the river. He conceived of three different historical relationships between rivers and structural features: (1) Newly uplifted land surfaces have rivers that flow down the initial slope of the uplift; these relationships he termed consequent. (2) A river may be older than an uplift that it crosses because it has been able to maintain its course by eroding downward as the uplift progresses; this relationship he named antecedent. (3) An uplifted block may have been buried by younger deposits upon which a river becomes established. The river, in cutting downward, uncovers the uplifted block and becomes incised into it; this relationship he called superimposed.The geologic history of the Colorado River involves all three relationships. In addition, although the position of the river course through a particular structural barrier may have been the result of superposition, the depth of the canyon at that point may be largely due to renewed uplift of the barrier; such deepening of the canyon, therefore, is due to antecedence. The problem of the Colorado River remains today very much as G. K. Gilbert stated it nearly 100 years ago: "How much is antecedent and how much is superimposed?" The question must be asked separately for each stretch of the river.
Monitoring changes in the Platte River riparian corridor with serial LiDAR surveys
Kinzel, Paul J.; Nelson, Jonathan M.; Wright, C. Wayne
2006-01-01
The Platte River in central Nebraska is a wide, sand-bedded river that provides habitat for migratory water birds along the North American flyway. The central Platte River functions as critical habitat for the endangered whooping crane (Grus americana) and also is an important habitat for the endangered least tern (Sterna antillarum) and the threatened piping plover (Charadrius melodus). Upstream water-resource development over the last century has decreased the water and sediment supplied to the central Platte River. This has resulted in vegetation encroachment and narrowing of Platte River channels. The National Academy of Sciences' National Research Council, in a recent review of these critical habitat designations, concluded that the current morphology of Platte River channels is limiting the recovery of the endangered and threatened avian species. Habitat-enhancement efforts along the Platte River currently (2006) are focused on the clearing of vegetation from in-channel and riparian areas, whereas future plans propose the release of water from upstream dams as a means to prevent vegetation from encroaching on the active river channel. For this reason, monitoring the physical response of the river channel to these management treatments is an important component of a proposed habitat recovery program. Understanding the effects of management strategies on Platte River riparian habitat also is a key objective of the U.S. Geological Survey's Platte River Priority Ecosystem Program (http://mcmcweb.er.usgs.gov/platte/). This fact sheet describes applications of LiDAR to monitor changes in the Platte River riparian corridor.