Search USGSSearch

SEARCH · Search USGS

Results for “Land and Reservoir Management”

Search indexed USGS publications on groundwater, aquifers, geologic maps, mineral resources and earthquakes. Explore source records by subject and place.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 73 records · Page 4Linked to original sources

Hydrologic and ecological investigations in the School Branch watershed, Hendricks County, Indiana—Water years 2016–2018

School Branch in Hendricks County in central Indiana, is a small stream with a variety of agricultural and suburban land uses that drains into the Eagle Creek Reservoir, a major source of drinking water for Indianapolis, Indiana. The School Branch watershed has become the focus of a collaborative partnership of Federal, State, and local agencies; a university research center; and agricultural producers to understand the effects of land use and management practices on water quality and water quantity in the watershed. The U.S. Geological Survey, in cooperation with the Indiana Department of Environmental Management, contributed to the School Branch partnership with the operation of three streamgages (03353415 School Branch at Maloney Road near Brownsburg, Indiana; 03353420 School Branch at County Road 750 North at Brownsburg, Indiana; and 03353430 School Branch at Noble Drive at Brownsburg, Indiana) and the operation of a continuous water-quality gage (also known as a supergage) at County Road 750 North that measured dissolved oxygen, pH, temperature, specific conductance, turbidity, nitrate, and orthophosphate. Additional efforts included the use of passive samplers to identify wastewater indicators; assessment of fish and macroinvertebrate communities and stream habitat to identify ecological impairment; sampling for nutrients and sediment to estimate loads; and using major ions, stable isotopes and nested groundwater monitoring wells at County Road 750 North to determine hydrologic connectivity between the groundwater and surface water. The objectives of this study were to collect surface and groundwater data to analyze the hydrology and water quality within the watershed. Total nitrogen yields were highest at the upstream site, Maloney Road, and indicated a mixture of nitrogen sources in the watershed. Differences found in total nitrogen loading patterns throughout the watershed may be linked to differences in hydrology and land-use management from site to site. The groundwater and surface water were shown to be highly connected, and except for some low-flow periods, the water was flowing from groundwater to the stream for most of the study period. Fish and macroinvertebrate communities show improvement from upstream to downstream, with increases in diversity, richness, and species sensitive to poor water quality and habitat. These increases were most likely due to improved habitat quality at the downstream station.

Indiana

Continuous estimation of baseflow in snowmelt-dominated streams and rivers in the Upper Colorado River Basin: A chemical hydrograph separation approach

Effective science-based management of water resources in large basins requires a qualitative understanding of hydrologic conditions and quantitative measures of the various components of the water budget, including difficult to measure components such as baseflow discharge to streams. Using widely available discharge and continuously collected specific conductance (SC) data, we adapted and applied a long established chemical hydrograph separation approach to quantify daily and representative annual baseflow discharge at fourteen streams and rivers at large spatial (> 1,000 km 2 watersheds) and temporal (up to 37 years) scales in the Upper Colorado River Basin. On average, annual baseflow was 21-58% of annual stream discharge, 13-45% of discharge during snowmelt, and 40-86% of discharge during low-flow conditions. Results suggest that reservoirs may act to store baseflow discharged to the stream during snowmelt and release that baseflow during low-flow conditions, and that irrigation return flows may contribute to increases in fall baseflow in heavily irrigated watersheds. The chemical hydrograph separation approach, and associated conceptual model defined here provide a basis for the identification of land use, management, and climate effects on baseflow.

Colorado, Utah

Post-Wildfire Hydrologic Hazards in the Wildland Urban Interface of Colorado and the Western United States

Following a wildfire, such as the 2002 Missionary Ridge fire, a number of hydrologic hazards may develop that can have an important impact on water resources, businesses, homes, reservoirs, roads, and utilities in the wildland urban interface (areas where homes and commercial developments are interspersed with wildlands) in mountainous areas of the Western United States. This fact sheet describes these hazards and identifies approaches to quantify them, thus enabling land and resource managers to plan for and mitigate the effects of these hazards. The fact sheet has been produced in association with the U.S. Geological Survey (USGS) Fire Science Thrust program and the Colorado Front Range Demonstration Project (CFRDP). The current (2007) focus of the CFRDP is on the Three Lakes watershed in Grand County, Colorado, which has applicability to many similar forested, mountain areas in the Western United States.

Fact Sheet

Recent changes in stream flashiness and flooding, and effects of flood management in North Carolina and Virginia

The southeastern United States has undergone anthropogenic changes in landscape structure, with the potential to increase (e.g., urbanization) and decrease (e.g., reservoir construction) stream flashiness and flooding. Assessment of the outcome of such change can provide insight into the efficacy of current strategies and policies to manage water resources. We (1) examined trends in precipitation, floods, and stream flashiness and (2) assessed the relative influence of land cover and flow-regulating features (e.g., best management practices and artificial water bodies) on stream flashiness from 1991 to 2013. We found mean annual precipitation decreased, which coincided with decreasing trends in floods. In contrast, stream flashiness, overall, showed an increasing trend during the period of study. However, upon closer examination, 20 watersheds showed stable stream flashiness, whereas 5 increased and 6 decreased in flashiness. Urban watersheds were among those that increased or decreased in flashiness. Watersheds that increased in stream flashiness gained more urban cover, lost more forested cover and had fewer best management practices installed than urban watersheds that decreased in stream flashiness. We found best management practices are more effective than artificial water bodies in regulating flashy floods. Flashiness index is a valuable and straightforward metric to characterize changes in streamflow and help to assess the efficacy of management interventions.

North Carolina, Virginia

Satellite monitoring of cyanobacterial harmful algal bloom frequency in recreational waters and drinking water sources

Cyanobacterial harmful algal blooms (cyanoHAB) cause extensive problems in lakes worldwide, including human and ecological health risks, anoxia and fish kills, and taste and odor problems. CyanoHABs are a particular concern in both recreational waters and drinking water sources because of their dense biomass and the risk of exposure to toxins. Successful cyanoHAB assessment using satellites may provide an indicator for human and ecological health protection. In this study, methods were developed to assess the utility of satellite technology for detecting cyanoHAB frequency of occurrence at locations of potential management interest. The European Space Agency's MEdium Resolution Imaging Spectrometer (MERIS) was evaluated to prepare for the equivalent series of Sentinel-3 Ocean and Land Colour Imagers (OLCI) launched in 2016 as part of the Copernicus program. Based on the 2012 National Lakes Assessment site evaluation guidelines and National Hydrography Dataset, the continental United States contains 275,897 lakes and reservoirs >1 ha in area. Results from this study show that 5.6% of waterbodies were resolvable by satellites with 300 m single-pixel resolution and 0.7% of waterbodies were resolvable when a three by three pixel (3 × 3-pixel) array was applied based on minimum Euclidian distance from shore. Satellite data were spatially joined to U.S. public water surface intake (PWSI) locations, where single-pixel resolution resolved 57% of the PWSI locations and a 3 × 3-pixel array resolved 33% of the PWSI locations. Recreational and drinking water sources in Florida and Ohio were ranked from 2008 through 2011 by cyanoHAB frequency above the World Health Organization’s (WHO) high threshold for risk of 100,000 cells mL −1 . The ranking identified waterbodies with values above the WHO high threshold, where Lake Apopka, FL (99.1%) and Grand Lake St. Marys, OH (83%) had the highest observed bloom frequencies per region. The method presented here may indicate locations with high exposure to cyanoHABs and therefore can be used to assist in prioritizing management resources and actions for recreational and drinking water sources.

Florida, Ohio

The rising tide of ocean diseases: Unsolved problems and research priorities

New studies have detected a rising number of reports of diseases in marine organisms such as corals, molluscs, turtles, mammals, and echinoderms over the past three decades. Despite the increasing disease load, microbiological, molecular, and theoretical tools for managing disease in the world's oceans are under-developed. Review of the new developments in the study of these diseases identifies five major unsolved problems and priorities for future research: (1) detecting origins and reservoirs for marine diseases and tracing the flow of some new pathogens from land to sea; (2) documenting the longevity and host range of infectious stages; (3) evaluating the effect of greater taxonomic diversity of marine relative to terrestrial hosts and pathogens; (4) pinpointing the facilitating role of anthropogenic agents as incubators and conveyors of marine pathogens; (5) adapting epidemiological models to analysis of marine disease.

Frontiers in Ecology and the Environment

Design of a naturalized flow regime—An example from the Lower Missouri River, USA

group of river managers, stakeholders, and scientists met during summer 2005 to design a more naturalized flow regime for the Lower Missouri River (LMOR). The objective was to comply with requirements under the U.S. Endangered Species Act to support reproduction and survival of threatened and endangered species, with emphasis on the endangered pallid sturgeon ( Scaphirhynchus albus ), while minimizing negative effects to existing social and economic benefits of prevailing river management. Specific hydrograph requirements for pallid sturgeon reproduction are unknown, hence much of the design process was based on features of the natural flow regime. Environmental flow components (EFCs) extracted from the reference natural flow regime were used to design and assess performance of alternative flow regimes. The design process incorporated a primary stage in which conceptual hydrographs were developed and assessed for their general ecological and social-economic performance. The second stage accounted for hydroclimatic variation by coding the conceptual hydrographs into reservoir release rules, adding constraints for downstream flooding and low-storage precludes, and running the rules through 100 years of hydroclimatic simulation. The output flow regimes were then evaluated for presumed ecological benefits based on how closely they resembled EFCs in the reference natural flow regime. Flow regimes also were assessed for social-economic cost indicators, including days of flooding of low-lying agricultural land, days over flood stage, and storage levels in system reservoirs. Our experience with flow-regime design on the LMOR underscored the lack of confidence the stakeholders place in the value of the natural flow regime as a measure of ecosystem benefit in the absence of fundamental scientific documentation. Stakeholders desired proof of ecological benefits commensurate with the certainty of economic losses. We also gained insight into the processes of integrating science into a collaborative management exercise. Although the 2005 collaborative effort failed to reach a consensus among stakeholders on a naturalized flow regime, the process was successful in pilot-testing a design approach; it helped focus scienctific efforts on key knowledge gaps; and it demonstrated the potential for collaborations among scientists, stakeholders, and managers in river management decision making.

Lower Missouri River

Mercury and methylmercury in reservoirs in Indiana

Mercury (Hg) is an element that occurs naturally, but evidence suggests that human activities have resulted in increased amounts being released to the atmosphere and land surface. When Hg is converted to methylmercury (MeHg) in aquatic ecosystems, MeHg accumulates and increases in the food web so that some fish contain levels which pose a health risk to humans and wildlife that consume these fish. Reservoirs unlike natural lakes, are a part of river systems that are managed for flood control. Data compiled and interpreted for six flood-control reservoirs in Indiana showed a relation between Hg transport, MeHg formation in water, and MeHg in fish that was influenced by physical, chemical, and biological differences among the reservoirs. Existing information precludes a uniform comparison of Hg and MeHg in all reservoirs in the State, but factors and conditions were identified that can indicate where and when Hg and MeHg levels in reservoirs could be highest. As part of a statewide monitoring network for Hg and MeHg in Indiana streams, 66 water samples were collected from four reservoir tailwater sites (downstream near the dams) on a quarterly schedule for 5 years. The reservoirs were Brookville Lake, Cagles Mill Lake, J. Edward Roush Lake, and Mississinewa Lake. Particulate-bound Hg concentrations were significantly lower in tailwater samples than in samples from free-flowing streams in the statewide network. (Free-flowing streams were not affected by dams and were not upstream from these reservoirs.) These data indicated the reduced flow velocity of water upstream from dams was allowing particulate-bound Hg to settle out of the water in the reservoir pools. The concentration ratios of MeHg to Hg were significantly higher in the tailwater samples than in samples from free-flowing streams, and the MeHg to Hg ratios were significantly higher in summer than in other seasons. To evaluate the conditions related to MeHg formation, pools of three reservoirs (Brookville Lake, Monroe Lake, and Patoka Lake) were investigated during summer hydrologic conditions. Water temperature and dissolved oxygen were measured from the water surface to the lake bottom at 10 to 17 transects across each reservoir to identify three thermal strata, defined by water temperature, dissolved oxygen concentration, and depth. Depth-specific water samples were collected from these thermal strata throughout each reservoir, from the headwaters to the dam and from the tailwater. Mercury concentrations higher than 0.04 nanogram per liter (ng/L) were detected in all 53 samples, and MeHg concentrations higher than 0.04 ng/L were detected in 53 percent of the samples. The investigation found a zone of water below 8 or 9 meters, with temperatures less than 18 degrees Celsius and dissolved oxygen less than 3.5 milligrams per liter, extending through nearly half the reservoir area in Monroe Lake and Patoka Lake. This zone had abundant dissolved MeHg and concentration ratios of dissolved MeHg to Hg that ranged from 25 to 82 percent. This zone also had water with pH less than 7 and decreased dissolved sulfate, conditions indicating sulfate reduction by microorganisms that promoted a high potential for the conversion of Hg to MeHg. Reservoir outflow came from this zone at Monroe Lake and contributed to a tailwater concentration ratio for dissolved MeHg to Hg of 56 percent. Reservoir outflow at Patoka Lake was not from this zone, and dissolved MeHg was not detected in the tailwater. In contrast, samples from the summer pool at Brookville Lake had no MeHg detections even though Hg was detected, probably because the water pH higher than 7 inhibited sulfate reduction and did not promote the conversion of Hg to MeHg. Mercury and MeHg concentrations and the concentration ratios of MeHg to Hg in water varied among the six reservoirs in Indiana, and the differences were related to a combination of factors that could apply to other reservoirs. In areas with moderate to high rates of atmospheric Hg wet and dry deposition, Hg runoff and transport to streams and reservoirs was potentially highest for reservoirs with heavily forested watersheds in steep terrains of near-surface bedrock. Methylmercury concentrations and concentration ratios of MeHg to Hg were highest for reservoirs with the longest summer pools and highest inflow-to-outflow retention times, where water-chemistry conditions favoring sulfate reduction promoted conversion of Hg to MeHg. Methylmercury (reported as Hg) in fish-tissue samples collected for the State fish consumption advisory program was used to describe MeHg food-web accumulation and magnification in the reservoirs. The highest percentages of fish-tissue samples with Hg concentrations that exceeded the criterion of 0.30 milligram per kilogram for protection of human health were from Monroe Lake (38 percent) and Patoka Lake (33 percent). A review of the number and size of fish species caught from these two reservoirs resulted in two implications for fish consumption by humans. First, the highest numbers of fish harvested for potential human consumption were species more likely to have MeHg concentrations lower than the human-health criterion (crappie, bluegill, and catfish). Second, although largemouth bass were likely to have MeHg concentrations higher than the human-health criterion, they were caught and released more often than they were harvested. However, the average size largemouth bass (in both reservoirs) and above-average size walleye (in Monroe Lake) that were harvested for potential human consumption were likely to have MeHg concentrations higher than the human-health criterion.

Indiana

The blue carbon reservoirs from Maine to Long Island, NY

In response to the New England Governor and Eastern Canadian Premier 2017 Climate Change Action Plan recommendation to “manage blue carbon resources to preserve and enhance their existing carbon reservoirs,” the U.S. Environmental Protection Agency (EPA) convened a New England Blue Carbon Inventory Workgroup, comprised of a variety of federal, state, academic, and non-profit organizations to develop an inventory of blue carbon stocks from Maine to Long Island, New York. The Workgroup focused its inventory efforts on salt marshes and eelgrass meadows, leveraging existing habitat maps for geographic data. Existing data for soil organic carbon stocks were then used to calculate blue carbon stock estimates. For visual display purposes, sediment carbon heat maps were developed to highlight areas of greatest carbon accumulation. The habitat distribution and sediment carbon heat maps can be accessed on the Northeast Ocean Data Portal (www.northeastoceandata.org/eelgrass) which is a public source of expert-reviewed, interactive maps and data on the ocean ecosystem, economy, and culture of the northeastern United States and can be used to facilitate decision making by government agencies, tribal nations, businesses, non-governmental organizations (NGOs), academic institutions, and individuals. Based on available data and Workgroup calculations, the target geographic area has an estimated 218,222 acres of eelgrass meadows, salt marsh and saline Phragmites, which are estimated to provide a reservoir of 7,523,568 megagrams of blue carbon, or the equivalent to the annual carbon emissions from over 5,944,024 passenger vehicles. Due to data limitations, the carbon stock estimate represents a mere fraction of the actual quantity of accumulated carbon in these habitats. The findings from the Workgroup’s efforts and the resulting map products can help inform land and coastal management policies, fisheries management, and climate change mitigation practices. Further refinements and expansion of data are needed, including more detailed habitat maps, deeper soil core data for soil organic carbon content, and inclusion of more marine flora into calculations.

Connecticut, Maine, Massachusetts, New Hampshire,

Effects of capture depth on walleye hooking mortality during ice fishing

Length-based regulations are a common tool used to limit fishing mortality by controlling the size of fish harvested. While such regulations are helpful in managing fish populations, mortality associated with catch-and-release fishing may negatively impact a fishery. We evaluated factors affecting hooking mortality of walleye ( Sander vitreus ) in 2 mainstem Missouri River reservoirs in South Dakota. Winter walleye hooking mortality was evaluated during the ice fishing season in February and March 2020. After capture, walleye ( n = 55) were placed into holding pens for 12 to 72 h to monitor postrelease mortality. Hooking mortality was found to be 20% following angling. Capture depth, landing time, and time in pen were the most influential variables on probability of hooking mortality ( p m ). We observed a sharp increase in p m for walleye captured at depths from 10 to 12 m, where the probability of mortality for fish increased appreciably from 5 to 37%, respectively. Our findings indicate that hooking mortality during the ice fishing season can be substantial in lakes where walleye angling occurs at depths greater than 10 m.

South Dakota

Leveraging multimission satellite data for spatiotemporally coherent cyanoHAB monitoring

Cyanobacteria harmful algal blooms (cyanoHABs) present a critical public health challenge for aquatic resource and public health managers. Satellite remote sensing is well-positioned to aid in the identification and mapping of cyanoHABs and their dynamics, giving freshwater resource managers a tool for both rapid and long-term protection of public health. Monitoring cyanoHABs in lakes and reservoirs with remote sensing requires robust processing techniques for generating accurate and consistent products across local and global scales at high revisit rates. We leveraged the high spatial and temporal resolution chlorophyll-a (Chl a ) and phycocyanin (PC) maps from two multispectral satellite sensors, the Sentinel-2 (S2) MultiSpectral Instrument (MSI) and the Sentinel-3 (S3) Ocean Land Colour Instrument (OLCI) respectively, to study bloom dynamics in Utah Lake, United States, for 2018. We used established Mixture Density Networks (MDNs) to map Chl a from MSI and train new MDNs for PC retrieval from OLCI, using the same architecture and training dataset previously proven for PC retrieval from hyperspectral imagery. Our assessment suggests lower median uncertainties and biases (i.e., 42% and -4%, respectively) than that of existing top-performing PC algorithms. Additionally, we compared bloom trends in MDN-based PC and Chl a products to those from a satellite-derived cyanobacteria cell density estimator, the cyanobacteria index (CI-cyano), to evaluate their utility in the context of public health risk management. Our comprehensive analyses indicate increased spatiotemporal coherence of bloom magnitude, frequency, occurrence, and extent of MDN-based maps compared to CI-cyano and potential for use in cyanoHAB monitoring for public health and aquatic resource managers.

Utah

Measurement of cyanobacteria bloom magnitude using satellite remote sensing

Cyanobacterial harmful algal blooms (cyanoHABs) are a serious environmental, water quality and public health issue worldwide because of their ability to form dense biomass and produce toxins. Models and algorithms have been developed to detect and quantify cyanoHABs biomass using remotely sensed data but not for quantifying bloom magnitude, information that would guide water quality management decisions. We propose a method to quantify seasonal and annual cyanoHAB magnitude in lakes and reservoirs. The magnitude is the spatio-temporal mean of weekly or biweekly maximum cyanobacteria biomass for the season or year. CyanoHAB biomass is quantified using a standard reflectance spectral shape-based algorithm that uses data from Medium Resolution Imaging Spectrometer (MERIS). We demonstrate the method to quantify annual and seasonal cyanoHAB magnitude in Florida and Ohio respectively during 2003-2011 and rank the lakes based on median magnitude over the study period. The new method can be applied to Ocean Land Color Imager (OLCI) on Sentinel-3 data for assessment of cyanoHABs and the change over time, even with issues such as variable data acquisition frequency or sensor calibration uncertainties between satellites. CyanoHAB magnitude can support monitoring and management decision-making for recreational and drinking water sources.

Florida, Ohio

Climate, invasive species and land use drive population dynamics of a cold-water specialist

Climate change is an additional stressor in a complex suite of threats facing freshwater biodiversity, particularly for cold-water fishes. Research addressing the consequences of climate change on cold-water fish has generally focused on temperature limits defining spatial distributions, largely ignoring how climatic variation influences population dynamics in the context of other existing stressors. We used long-term data from 92 populations of bull trout Salvelinus confluentus – one of North America's most cold-adapted fishes – to quantify additive and interactive effects of climate, invasive species and land use on population dynamics (abundance, variability and growth rate). Populations were generally depressed, more variable and declining where spawning and rearing stream habitat was limited, invasive species and land use were prevalent and stream temperatures were highest. Increasing stream temperature acted additively and independently, whereas land use and invasive species had additive and interactive effects (i.e. the impact of one stressor depended on exposure to the other stressor). Most (58%–78%) of the explained variation in population dynamics was attributed to the presence of invasive species, differences in life history and management actions in foraging habitats in rivers, lakes and reservoirs. Although invasive fishes had strong negative effects on populations in foraging habitats, proactive control programmes appeared to effectively temper their negative impact. Synthesis and applications . Long-term demographic data emphasize that climate warming will exacerbate imperilment of cold-water specialists like bull trout, yet other stressors – especially invasive fishes – are immediate threats that can be addressed by proactive management actions. Therefore, climate-adaptation strategies for freshwater biodiversity should consider existing abiotic and biotic stressors, some of which provide potential and realized opportunity for conservation of freshwater biodiversity in a warming world.

Journal of Applied Ecology

Toward explaining nitrogen and phosphorus trends in Chesapeake Bay tributaries, 1992-2012

Understanding trends in stream chemistry is critical to watershed management, and often complicated by multiple contaminant sources and landscape conditions changing over varying time scales. We adapted spatially-referenced regression (SPARROW) to infer causes of recent nutrient trends in Chesapeake Bay tributaries by relating observed fluxes during 1992, 2002, and 2012 to contemporary inputs and watershed conditions. The annual flow-normalized nitrogen flux to the bay from its watershed declined by 14 percent to 127,000 Mg (metric tons) between 1992 and 2012, due primarily (more than 80 percent of the decline) to reduced point sources. The remainder of the decline was due to reduced atmospheric deposition (13 percent) and urban non-point sources. Agricultural inputs, which contribute most nitrogen to the bay, changed little, although trends in the average nitrogen yield (flux per unit area) from cropland and pasture to streams in some settings suggest possible effects of evolving nutrient applications or other land management practices. Point sources of phosphorus to local streams declined by half between 1992 and 2012, while non-point inputs were relatively unchanged. Annual phosphorus delivery to the bay increased by 9 percent to 9,570 Mg between 1992 and 2012, however, due mainly to reduced retention in the Susquehanna River at Conowingo Reservoir.

Delaware, Maryland, New Jersey, Pennsylvania, Virg

Reconnaissance of chemical and biological quality in the Owyhee River from the Oregon State line to the Owyhee Reservoir, Oregon, 2001–02

The Owyhee River drains an extremely rugged and sparsely populated landscape in northern Nevada, southwestern Idaho, and eastern Oregon. Most of the segment between the Oregon State line and Lake Owyhee is part of the National Wild and Scenic Rivers System, and few water-quality data exist for evaluating environmental impacts. As a result, the U.S. Geological Survey, in cooperation with the Bureau of Land Management, assessed this river segment to characterize chemical and biological quality of the river, identify where designated beneficial uses are met and where changes in stream quality occur, and provide data needed to address activities related to environmental impact assessments and Total Maximum Daily Loads. Water-quality issues identified at one or more sites were water temperature, suspended sediment, dissolved oxygen, pH, nutrients, trace elements, fecal bacteria, benthic invertebrate communities, and periphyton communities. Generally, summer water temperatures routinely exceeded Oregon's maximum 7-day average criteria of 17.8 degrees Celsius. The presence of few coldwater taxa in benthic invertebrate communities supports this observation. Suspended-sediment concentrations during summer base flow were less than 10 milligrams per liter (mg/L). Dissolved solids concentrations ranged from 46 to 222 mg/L, were highest during base flow, and tended to increase in a downstream direction. Chemical compositions of water samples indicated that large proportions of upland-derived water extend to the lower reaches of the study area during spring runoff. Dissolved fluoride and arsenic concentrations were highest during base flow and may be a result of geothermal springs discharging to the river. No dissolved selenium was detected. Upstream from the Rome area, spring runoff concentrations of suspended sediment ranged from 0 to 52 mg/L, and all except at the Three Forks site were typically below 20 mg/L. Stream-bottom materials from the North Fork Owyhee River, an area with no mines, were enriched with nine trace elements, which indicates that this basin may be a natural source of these elements. Near Rome, the part of the study area not included in the National Wild and Scenic Rivers System, land-use impacts resulted in elevated populations of Escherichia coli bacteria ( E. coli ) during base flow and elevated concentrations of nitrogen and phosphorus during spring runoff. Sites in this area had the highest numbers of benthic invertebrates; the fewest Ephemeroptera, Plecoptera, and Trichoptera taxa; and the highest Hilsenhoff Biotic Index scores. These results suggest degraded stream quality. Periphyton communities at sites in this area approached nuisance levels and could cause significant dissolved oxygen depletions and pH values that exceed Oregon's recommended criteria. Stream-bottom materials from Jordan Creek were enriched with mercury and manganese, which probably were ultimately caused by past mining in that basin. Below Crooked Creek, elevated suspended sediment concentrations (142 mg/L), phosphorus concentrations (0.23 mg/L), and E. coli populations (370 most probable number per 100 milliliters) during the largest spring runoff event could be the result of inputs at the lower end of Jordan Valley and (or) inputs from Crooked Creek. The New Zealand Mud Snail, a highly competitive gastropod introduced to the Snake River in the 1980s, was collected just downstream from the Crooked Creek confluence.

Idaho;Nevada;Oregon

Natural soil reservoirs for human pathogenic and fecal indicator bacteria

Soils receive inputs of human pathogenic and indicator bacteria through land application of animal manures or sewage sludge, and inputs by wildlife. Soil is an extremely heterogeneous substrate and contains meso- and macrofauna that may be reservoirs for bacteria of human health concern. The ability to detect and quantify bacteria of human health concern is important in risk assessments and in evaluating the efficacy of agricultural soil management practices that are protective of crop quality and protective of adjacent water resources. The present chapter describes the distribution of selected Gram-positive and Gram-negative bacteria in soils. Methods for detecting and quantifying soilborne bacteria including extraction, enrichment using immunomagnetic capture, culturing, molecular detection and deep sequencing of metagenomic DNA to detect pathogens are overviewed. Methods for strain phenotypic and genotypic characterization are presented, as well as how comparison with clinical isolates can inform the potential for human health risk.

Book chapter

Sediment yields of Wisconsin streams

Sediment in Wisconsin streams causes economic and engineering problems in water management and reduces the value of water for nearly all uses. Sediment produces problems such as reduced reservoir capacity, navigation hazards, increased cost of water treatment, property damage, temporary loss of farmland, destruction of feeding and nesting grounds of fish, and destruction of wildlife habitat. Sediment in water also reduces the aesthetic value of surface waters and is detrimental to the State's tourist and recreation industry. The yield of sediment from a drainage basin is subject to many environmental influences. Most sediment results from the weathering and erosion of soil and rock materials. Other factors such as rainfall intensity, runoff rate, topography, rock type, soil characteristics, vegetal cover, and land use also influence the rate of sediment production and movement. An understanding of the many parameters that influence sediment yield is a basic need for managing the State's water resources. The purpose of this report is to describe the magnitude and variability of sediment in Wisconsin streams, to relate sediment yields to the local environment, and to identify areas that need further study. The report is based on sediment data from 44 stream-gaging sites throughout the State. Determination of local areas of erosion and deposition are beyond the scope of the report.

Wisconsin

Water management, agriculture, and ground-water supplies

Encyclopedic data on world geography strikingly illustrate the drastic inequity in the distribution of the world's water supply. About 97 percent of the total volume of water is in the world's oceans. The area of continents and islands not under icecaps, glaciers, lakes, and inland seas is about 57.5 million square miles, of which 18 million (36 percent) is arid to semiarid. The total world supply of water is about 326.5 million cubic miles, of which about 317 million is in the oceans and about 9.4 million is in the land areas. Atmospheric moisture is equivalent to only about 3,100 cubic miles of water. The available and accessible supply of ground water in the United States is somewhat more than 53,000 cubic miles (about 180 billion acre ft). The amount of fresh water on the land areas of the world at any one time is roughly 30,300 cubic miles and more than a fourth of this is in large fresh-water lakes on the North American Continent. Annual recharge of ground water in the United States may average somewhat more than 1 billion acre-feet yearly, but the total volume of ground water in storage is equivalent to all the recharge in about the last 160 years. This accumulation of ground water is the nation's only reserve water resource, but already it is being withdrawn or mined on a large scale in a few areas. The principal withdrawals of water in the United States are for agriculture and industry. Only 7.4 percent of agricultural land is irrigated, however; so natural soil moisture is the principal source of agricultural water, and on that basis agriculture is incomparably the largest water user. In view of current forecasts of population and industrial expansion, new commitments of water for agriculture should be scrutinized very closely, and thorough justification should be required. The 17 Western States no longer contain all the large irrigation developments. Nearly 10 percent of the irrigated area is in States east of the western bloc, chiefly in several Southeastern States. Ground water is not completely 'self-renewing' because, where it is being mined, the reserve is being diminished and the reserve would be renewed only if pumping were stopped. Water is being mined at the rate of 5 million acre-feet per year in Arizona and 6 million in the High Plains of Texas. In contrast, water has been going into storage in the Snake River Plain of Idaho, where deep percolation from surface-water irrigation has added about 10 million acre-feet of storage since irrigation began. Situations in California illustrate problems of land subsidence resulting from pumping and use of water, and deterioration of ground-water reservoirs due to sea-water invasion. Much water development in the United States has been haphazard and rarely has there been integrated development of ground water and surface water. Competition is sharpening and new codes of water law are in the making. New laws, however, will not prevent the consequences of bad management. An important task for water management is to recognize the contingencies that may arise in the future and to prepare for them. The three most important tasks at hand are to make more efficient use of water, to develop improved quantitative evaluations of water supplies arid their quality, and to develop management practices which are based on scientific hydrology.

Circular