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At least 1,081 records · Page 60Linked to original sources
USGS2008

Environmental presence and persistence of pharmaceuticals: An overview

Emerging contaminants (ECs) in the environment – that is, chemicals with domestic, municipal, industrial, or agricultural sources that are not commonly monitored but may have the potential for adverse environmental effects – is a rapidly growing field of research. The use of “emerging” is not intended to infer that the presence of these compounds in the environment is new. These chemicals have been released into the environment as long as they have been in production or, in the case of hormones and other endogenous compounds, since the rise of animal life. What is emerging is the interest by the scientific and lay communities in the presence of these chemicals in the environment, the analytical capabilities required for detection, and the subtle effects that very small concentrations of these chemicals appear to have on aquatic biota. In December 2006, Environmental Science & Technology devoted an entire special issue (volume 40, number 23) to the topic of ECs, illustrating the increased interest in the subject. Within the EGs, one particular class that has seen a substantial increase in research over the past 10 years is pharmaceuticals and personal-care products (PPCPs). This increased research interest can be demonstrated by several means, including requests for proposals from funding agencies, but the clearest indication of a focused effort to understand the introduction, transformation, and potential health and environmental effects of PPCPs and ECs, in general, is the number of published reports. This increase can be shown by examining six environmental journals that regularly publish PPCP-related papers – Chemosphere , Environmental Science & Technology , Environmental Toxicology and Chemistry , Science of the Total Environment , Water Research , and Water Science and Technology . In 1998 there were 22 papers published on pharmaceuticals, antibiotics, or drugs in these 6 journals; by 2006, this number increased sixfold to 132 papers (Figure 1.1). This growth can be attributed to a number of factors. The presence of pharmaceuticals in surface-water samples from Europe and the United States was documented in several sentinel papers. These ground-breaking works encouraged other scientists to examine the rivers, streams, lakes, and reservoirs in their regions for such chemicals. In addition, the intense public attention paid to news reports on the environmental detections of these chemicals and possible effects of aquatic life has made this issue visible to the wastewater-treatment, drinking-water treatment, and regulatory communities. This has driven the funding bodies associated with these communities to fund studies or request proposals that address the presence, fate, and effects of PPCPs in aquatic systems. The release of the first comprehensive reconnaissance of pharmaceuticals and other wastewater contaminants in the United States provides an example of the intense media interest in this topic. Within 6 days on online publication of this study, 72 newspapers across the United States had published articles describing the results, either locally written or based on international media syndicate reports. There also was substantial concurrent coverage by local and national radio and television outlets, including the Cable News Network, ABC World News Tonight , and National Public Radio. A substantial fraction of these news stories may be attributable to press releases and media briefings prior to publication. However, the interest by television and print journalists in reporting the results of a peer-reviewed journal article to the general public was motivated by the recognition that describing the presence of PPCPs in water supplies would be of interest to the public. To better convey the results of the study published by Koplin et al. to the public, a separate general-interest fact sheet was published to summarize the important points of the study. Because PPCPs are commonly and widely used by individuals, there is likely a preexisting, personal identification with these compounds that does not occur for the wide range of other organic and inorganic contaminants whose presence in the environment has previously been described. This greater public “name recognition” makes itself known through the media to the regulatory and technical community and has prompted interest in sponsoring research that defines the composition and concentrations of PPCPs in potential sources and their fate and effects following relase into the environment. Independent of the drivers that potentially fuel the interest in studies of PPCPs, it is clear that PPCP research has grown beyond surface-water studies to examine issues such as: • Presence in other matrices, such as groundwater, landfill leachates, sediments, and biosolids. • Environmental transport and fate in surface water, groundwater, and soils amended with reclaimed water or biosolids. • PPCP source elucidation, such as wastewater treatment plant (WWTP) effluents, confined animal feeding operations (CAFOs), and aquaculture. • Removal during wastewater and drinking-water treatment. • Effects on aquatic ecosystems, terrestrial ecosystems, and human health. The chapters in this book provide an extensive examination of current environmental pharmaceutical research and are divided into three sections: “Occurrence and Analysis of Pharmaceuticals in the Environment,” “Environment Fate and Transformations of Veterinary Pharmaceuticals,” and “treatment of Pharmaceuticals in Drinking Water and Wastewater.” The purpose of this introductory overview chapter is to outline current (2004-2006) knowledge about the presence and concentration of PPCPs as described in the published literature. Previous reviews should be consulted for discussions on pre-2004 publications. Those reviews will provide the reader with a comprehensive introduction to the topic of PPCPs in the environment. This chapter describes the sources of PPCPs and other organic contaminants often associated with human wastewater into the environment, the range of concentrations present in various environmental compartments, and the potential routes of removal/sequestration. An overview of the sources and fate of veterinary pharmaceuticals will be discussed in Chapter 5, “Fate and Transport of Veterinary Medicines in the Soil Environment.”

Book chapter↗
USGS2015

Dreissenid mussel research priorities workshop

Currently, dreissenid mussels have yet to be detected in the northwestern part of the United States and western Canada. Infestation of one of the jurisdictions within the mussel-free Pacific Northwest would likely have significant economic, soci­etal and environmental implications for the entire region. Understanding the biology and environmental tolerances of dreissenid mussels, and effectiveness of various man­agement strategies, is key to prevention. On November 4-5, 2015, the Aquatic Bioinvasion Research and Policy Institute and the Center for Lakes and Reservoirs at Portland State University, the US Geological Survey, and the Pacific States Marine Fisheries Commission, convened a Dreissenid Mussel Research Priorities Workshop funded by the Great Northern Landscape Conservation Cooperative. The purpose of the workshop was to review dreissenid research priorities in the 2010 Quagga-Zebra Mussel Action Plan for Western U.S. Waters, reassess those priorities, incorporate new information and emerging trends, and develop priorities to strategically focus research efforts on zebra and quagga mussels in the Pacific Northwest and ensure that future research is focused on the highest priorities. It is important to note that there is some repetition among dreissenid research priority categories (e.g., prevention, detection, control, monitoring, and biology). Workshop participants with research experience in dreissenid mussel biology and management were identified by a literature review. State and federal agency managers were also invited to the workshop to ensure relevancy and practicality of the work­shop outcomes. A total of 28 experts (see sidebar) in mussel biology, ecology, and management attended the workshop.

Conference Paper↗
USGS2015

Understanding natural capital

This chapter serves to introduce the geophysics of Neotropical steeplands. Topics are covered in a general manner with hyperlinks to active research and monitoring sites (such as the National Hurricane Center and US Geological Survey publication). Topics covered include ‘tropical climate and weather,’ ‘climate variations and trends,’ Neotropical ‘geology, and soils,’ ‘hillslopes and erosion,’ ‘lakes and reservoirs,’ and ‘effects of land cover on water quality and quantity.’ Obviously, this is a lot of information to cover in a short chapter, hence the use of hyperlinks. The last theme ‘effects of land cover on water quality and quantity’ is covered by case studies, in all of which I have been centrally involved. These studies were chosen because they are among the few studies with sufficient data of high enough quality to reach definitive conclusions.

Book chapter↗
USGS2009

Zoogeography, conservation, and ecology of crayfishes within the Cheat River basin of the Upper Monongehela River drainage, West Virginia

During summer 2008, we studied the geographic distribution and conservation status of crayfishes within the Cheat River basin of the upper Monongahela River drainage. Stream sites (n = 73) were selected with a probabilistic sampling design, whereas one reservoir (Cheat Lake) and seven terrestrial sites for burrowing crayfishes were selected non-randomly. Stream crayfishes were seined or hand-collected following standardized protocols, and physical habitat and physiochemical water quality parameters were recorded at each site. Cambarus b. bartonii , C. carinirostris , and Orconectes obscurus were initially documented within the Cheat River basin in 1956. Surveys conducted in the late 1980s documented the presence of C. carinirostris , C. dubius , C. monongalensis , and O. obscurus . Our data on crayfish distributions from 2008 are consistent with those of the late 1980s. Survey data from 1956, however, indicated depauperate populations of Cambarus throughout the basin during a time period of basin-wide habitat and water quality degradation. Currently, C. carinirostris is abundant throughout the Cheat River system, except in areas with low pH and elevated conductivity. Orconectes obscurus populations within the Cheat River basin are stable and occur primarily in higher stream orders. Future astacological efforts in the Cheat River basin, however, are needed to define the distribution of the basins two burrowing species, C. dubius and C. monongalensis .

West Vigninia↗
USGS2018

Sediment transport and deposition

Sediment transport and deposition (sedimentation) occurs from natural and anthropogenic sources in rivers, lakes, and reservoirs. Substantial changes in sediment transport (such as a major increase or decrease in sediment supply) can impact aquatic ecosystems that depend on a particular sediment quantity and particle size, for example, through altering stream-channel geomorphology or fish habitat. For human communities that rely on surface water resources, sedimentation can impact water supply and quality. Sedimentation in reservoirs affects water supply by reducing the reservoir volume available to store water. Sediment, as well as the nutrients and chemicals adsorbed in sediment, can serve as pollutants that decrease water quality and make water treatment necessary and costly.

California↗
USGS2021

Cyanotoxin occurrence in the United States: A 20 year retrospective

Cyanobacterial blooms, and associated cyanotoxin occurrence, are a concern because of the potential harms posed to humans, wildlife, and aquatic ecosystem health. Evidence suggests the magnitude, frequency, and duration of cyanobacterial blooms are increasing, and these events represent a significant challenge to freshwaters and, increasingly, marine waters, worldwide. Cyanobacterial blooms routinely receive local and national attention because of occurrence in new locations, recreational closures, drinking-water impacts, animal illnesses and deaths, scientific advances, and novel management and mitigation strategies. Due to public information campaigns at local, state, and federal levels, the public is generally aware of what cyanobacterial blooms look like and potential risks posed to human and animal health. It is difficult now to imagine a time when cyanobacterial blooms were considered an occasional nuisance in lakes and reservoirs, well-known only by limnologists. When I began my career over twenty years ago, however, that was the status. Cyanobacteria were just beginning to capture attention, and they certainly captured mine.

Lakeline↗
USGS2022

Klamath natural flow study, Upper Klamath Basin groundwater flow model

The purpose of the Upper Klamath Basin Groundwater Flow Model (UKBGFM) is to simulate groundwater conditions in the Upper Klamath Basin under historical and predevelopment conditions. The UKBGFM quantifies estimates of and changes in groundwater levels, storage, pumping, drainage flow to tile drains, evapotranspiration, and flow between the Upper Klamath Basin and neighboring basins. The quantifications of base flow to streams and seepage to and from lakes and reservoirs can be used as inputs to the RiverWare Mass Balance Model (Zagona and others, 2001), a companion model being developed as part of the Klamath Natural Flow Study (KNFS).

California, Oregon↗
USGS1989

A comparison of aquatic macrophyte communities in regulated and non-regulated lakes, Voyageurs National Park and Boundary Waters Canoe Area, Minnesota

The effects of water-level regulation on aquatic macrophyte communities, individual plant species, and potential faunal habitat were investigated in a study of two regulated lakes and an unregulated lake in northern Minnesota. Water levels in Rainy Lake and Namakan Reservoir in Voyageurs National Park are regulated by dams. Natural annual fluctuations of 1.8 m are replaced with fluctuations of 1.1 m in Rainy Lake and 2.7 m in the five lakes that comprise Namakan Reservoir. In addition, springtime peaking of water levels in Namakan Reservoir is delayed by one month. After reaching the peak, water levels in the regulated lakes are held at that level through the summer and allowed to gradually decline through autumn and winter. This study was conducted by estimating the cover of each plant species in randomly placed quadrats along transects that followed depth contours in the lakes. These contours were selected to represent different plant habitats, as defined by the timing and duration of flooding and dewatering in unregulated Lac La Croix. Detrended correspondence analysis showed that the macrophyte communities at all depths of the regulated lakes differed from those in the unregulated lake. The differences were more profound in deeper parts of the littoral zone. Lac La Croix contained taxonomically and structurally diverse plant communities at all depths, maximizing faunal habitat. The greatest effect of the regulation on Rainy Lake was along transects at the depth that is never dewatered. There were only four taxa present; they were all erect aquatics that extended through the entire water column and offered little structurally diverse faunal habitat. The greatest effect of regulation on Namakan Lake was along transects at the depth where drawdown occurs in early winter and disturbance results from ice formation in the sediments. Rosette and mat-forming species were dominant, providing minimal faunal habitat. The hydrologic regime at Lac La Croix results in intermediate disturbance that maintains high diversity. There is too little disturbance from water-level fluctuations in Rainy Lake and too much disturbance in Namakan Reservoir, resulting in reduced diversity in both cases. The macrophyte communities of the regulated lake systems would benefit from a return to more natural hydrologic regimes. Namakan Reservoir should be regulated to reach its peak water level at the beginning of June, summer drawdowns should occur at both Rainy Lake and Namakan Reservoir, and the amplitude of annual drawdowns should vary between years but approximate 1.8 m. These hydrologic conditions should, over time, result in more diverse macrophyte communities and more diverse faunal habitat throughout the littoral zone of the regulated lakes.

Research/Resources Management↗
USGS2023

Waterfalls in reservoirs: Tracking the development of nickpoints in the sediments of declining reservoirs

Recent drought has resulted in dramatic lowering of the two largest water-storage reservoirs in the western United States: Lake Powell and Lake Mead. These decreases in reservoir elevations have resulted in the re-emergence of over 100 km of the Colorado and San Juan rivers at the upstream end of Lake Powell and over 80 km of the Colorado River at the upstream end of Lake Mead. Upon reservoir lowering, the rivers cut into the lake and delta deposits sometimes establishing a course different than the path of the historical channel. In two locations, the rivers have encountered resistant bedrock resulting in the formation of rapids or waterfalls. In a third location, on the Colorado River arm of Lake Powell near the mouth of the Dirty Devil River, a knickpoint is just beginning to form and a new rapid or waterfall may result if water levels continue to drop. We present repeat measurements with multibeam sonar of the riverbed at this location to document scour at the site of nickpoint formation. Between initial measurements made in October 2020 and the most recent measurements made in May 2022, the riverbed scoured by up to 11 m as the level of Lake Powell dropped by more than 18 m. These knickpoints in former reservoirs have several implications for river and reservoir management, including effects on river dynamics and upstream river ecosystems, impacts to river and reservoir navigation, and the formation of ecological barriers.

Utah↗
USGS2008

Hydrologic and water-quality characterization and modeling of the Onondaga Lake Basin, Onondaga County, New York

Onondaga Lake in Onondaga County, New York, has been identified as one of the Nation’s most contaminated lakes as a result of industrial and sanitary-sewer discharges and stormwater nonpoint sources, and has received priority cleanup status under the national Water Resources Development Act of 1990. A basin-scale precipitation-runoff model of the Onondaga Lake basin was identified as a desirable water-resources management tool to better understand the processes responsible for the generation of loads of sediment and nutrients that are transported to Onondaga Lake. During 2003–07, the U.S. Geological Survey (USGS) developed a model based on the computer program, Hydrological Simulation Program–FORTRAN (HSPF), which simulated overland flow to, and streamflow in, the major tributaries of Onondaga Lake, and loads of sediment, phosphorus, and nitrogen transported to the lake. The simulation period extends from October 1997 through September 2003. The Onondaga Lake basin was divided into 107 subbasins and within these subbasins, the land area was apportioned among 19 pervious and impervious land types on the basis of land use and land cover, hydrologic soil group (HSG), and aspect. Precipitation data were available from three sources as input to the model. The model simulated streamflow, water temperature, concentrations of dissolved oxygen, and concentrations and loads of sediment, orthophosphate, total phosphorus, nitrate, ammonia, and organic nitrogen in the four major tributaries to Onondaga Lake–Onondaga Creek, Harbor Brook, Ley Creek, and Ninemile Creek. Simulated flows were calibrated to data from nine USGS streamflow-monitoring sites; simulated nutrient concentrations and loads were calibrated to data collected at six of the nine streamflow-monitoring sites. Water-quality samples were collected, processed, and analyzed by personnel from the Onondaga County Department of Water Environment Protection. Several time series of flow, and sediment and nutrient loads were generated for known sources of these constituents, including the Tully Valley mudboils (flow and sediment), Otisco Lake (flow and nutrients), the Marcellus wastewater-treatment plant (flow and nutrients), and springs from carbonate bedrock (flow). Runoff from the impervious sewered areas of the City of Syracuse was adjusted for the quantity that was treatable at the county wastewater-treatment plant; the excess flows were routed to nearby streams through combined-sanitary-and-storm-sewer overflows. The mitigative effects that the Onondaga Reservoir and Otisco Lake were presumed to have on loads of sediment and particulate constituents were simulated by adjustment of parameter values that controlled sediment settling rates, deposition, and scour in the reservoir and lake. Graphical representations of observed and simulated data, and relevant statistics, were compared to assess model performance. Simulated daily and monthly streamflows were rated “very good” (within 10 percent of observed flows) at all calibration sites, except Onondaga Creek at Cardiff, which was rated “fair” (10–15 percent difference). Simulations of monthly average water temperatures were rated “very good” (within 7 percent of observed temperatures) at all sites. No observed data were available by which to directly assess the model’s simulation of suspended sediment loads. Available measured total suspended solids data provided an indirect means of comparison but, not surprisingly, yielded only “fair” to “poor” ratings (greater than 30 percent difference) for simulated monthly sediment loads at half the water-quality calibration sites. Simulations of monthly orthophosphate loads ranged from “very good” (within 15 percent of measured loads) at three sites to “poor” (greater than 35 percent difference) at one site; simulations of ammonia nitrogen loads ranged from “very good” at one site to “fair” (25–35 percent difference) at two sites. Simulations of monthly total phosphorus, nitrate, and organic nitrogen loads were generally rated “very good” at all calibration sites. Sources of uncertainty in model results were identified, including (1) errors in precipitation data, (2) limitations in model structure, (3) nonuniqueness of values for highly sensitive parameters, (4) errors or bias in data used to calibrate the different components of the model, (5) misclassification of land-use and land-cover data, (6) changes in land use during the simulation period, (7) unidentified sources or sinks of chemical loads and water-quality processes that varied over time, and (8) differences in scale between large calibrated subbasins and small subbasins to which calibrated parameter values were transferred. Uncertainty in simulations of water-quality constituents was compounded by uncertainty in the processes on which the water-quality simulations were based. Therefore, sediment simulations were affected by uncertainty in the simulation of hydrology, and nutrient simulations were affected by uncertainty in both the hydrologic and sediment processes, as well as, in simulations of water temperature and dissolved oxygen concentrations. The calibrated model can be used to simulate scenarios that represent planned or hypothetical development and implementation of best-management practices in the Onondaga Lake basin and to assess the effects that these changes and practices are likely to have on rural and urban nonpoint sources of pollution to Onondaga Lake. Model results also can be used as input to a hydrodynamic model of Onondaga Lake that is being developed by Onondaga County and to prioritize areas of the basin where mitigative measures to decrease sediment and nutrient loads could provide the greatest benefits to Onondaga Lake.

New York↗
USGS2026

Gerrard strain Rainbow Trout are not piscivorous in a shallow, polymictic reservoir

Objective Georgetown Lake (Montana, USA) is renowned for its multispecies salmonid fishery. Although many anglers target kokanee Oncorhynchus nerka in Georgetown Lake, the body length of kokanee has typically been considered unsatisfactory. To reduce the density of kokanee and increase the average size, Montana Fish, Wildlife & Parks began stocking the piscivorous Gerrard strain of Rainbow Trout O. mykiss (hereafter “Gerrard”) in 2015 to consume kokanee. In 2020, preliminary evidence suggested that the average length of kokanee greater than 200 mm increased by almost 40 mm. Methods To assess the efficacy of biocontrol through the introduction of a piscivore to predate on kokanee, we examined the diet composition of all potential predators (three strains of Rainbow Trout and Brook Trout Salvelinus fontinalis ) to determine the amount of predation on kokanee and to understand the feeding ecology of all potential predators. Results There was little evidence of piscivory in any predator and no evidence of Gerrards consuming kokanee. Gerrards exhibited a generalist feeding strategy, and there was dietary overlap and no difference in trophic position among Gerrards and other predators. Conclusions From a biological-control perspective, there is no benefit in continuing to stock Gerrards to reduce kokanee densities in Georgetown Lake. These findings underscore the challenge of predicting predator–prey relationships, as diet plasticity can lead to unexpected dynamics based on resource availability and habitat structure within aquatic ecosystems, highlighting the importance of evaluating management interventions, such as biocontrols, in different ecosystems.

Montana↗
USGS1985

Seepage study of six canals in Salt Lake County, Utah, 1982-1983

A study of selected reaches of the Utah and Salt Lake, Utah Lake Distributing, Provo Reservoir, Draper Irrigation, East Jordan, and Jordan and Salt Lake City Canals in Salt Lake County, Utah, was made to determine gains or losses of flow in those reaches. Three to five sets of seepage measurements were made on each canal during 1982 or 1983. Adjustments for fluctuations in flow were made from information obtained from water-stage recorders operated at selected locations during the time of each seepage run. The study showed an overall net loss of about 9.5 cubic feet per second in the Utah and Salt Lake Canal, 11.0 cubic feet per second in the Utah Lake Distributing canal, 20.5 cubic feet per second in the Provo Reservoir canal, 1.5 cubic feet per second in the Draper Irrigation Canal, and 4.0 cubic feet per second in the East Jordan canal. It also showed a net gain of about 6.0 cubic feet per second in the Jordan and Salt Lake City Canal. The gains and losses are attributed primarily to the relation of the canals to the depth of the water table near the canals.

Utah↗
USGS2005

Simulated effects of water-level changes in the Mississippi River and Pokegama Reservoir on ground-water levels, Grand Rapids area, Minnesota

The U.S. Geological Survey, in cooperation with the U.S. Army Corps of Engineers, used an existing, three-dimensional, numerical ground-water flow model (referred to as the calibrated model) to assess the effects of water-level changes in the Mississippi River and Pokegama Reservoir on ground-water levels in adjacent glaciofluvial aquifers in the Grand Rapids area of north-central Minnesota. Pokegama Reservoir consists of Pokegama Lake, Little Jay Gould Lake, Jay Gould Lake, Cut-off Lake, and Blackwater Lake. Water levels in the Pokegama Reservoir are regulated at Pokegama Dam on the Mississippi River west of Grand Rapids. A steady-state model was used, and simulations represent “worse-case” scenarios for the effects of lowering or raising the river and lake water levels. The simulated ground-water levels represent levels that would result if the river and lake stages permanently declined or rose by the specified amounts. Eight hypothetical scenarios were simulated by varying water levels in the Mississippi River and Pokegama Reservoir from values used in the calibrated model. In the simulations, water levels for the Mississippi River, riverine wetlands of the Mississippi River, and lakes of the Pokegama Reservoir were raised and lowered uniformly by 0.50, 1.00, 2.00, and 3.00 feet from calibrated water levels. The extent of aquifer water-level changes resulting from these river, wetland, and lake water-level changes varied because of the complex hydrogeology of the study area. A 1.00-foot decline in reservoir/river water levels caused a maximum simulated ground-water-level decline in the middle aquifer near Jay Gould and Little Jay Gould Lakes of 1.09 feet and a maximum simulated ground-water-level decline of 1.00 foot in the lower aquifer near Cut-off and Blackwater Lakes. The amount and extent of ground-water-level changes in the middle and lower aquifers can be explained by the thickness, extent, and connectivity of the aquifers. Surface-water/ground-water interactions near wetlands and lakes with water levels unchanged from the calibrated model resulted in small water-table altitude differences among the simulations. Results of the ground-water modeling indicate that lowering of the reservoir and river water levels by 1.00 foot likely will not substantially affect water levels in the middle and lower aquifers.

Minnesota↗
USGS2000

Techniques for estimating magnitude and frequency of peak flows for Pennsylvania streams

Regression equations for estimating the magnitude and frequency of floods on ungaged streams in Pennsylvania with drainage areas less that 2,000 square miles were developed on the basis of peak-flow data collected at 313 streamflow-gaging stations. All streamflow-gaging stations used in the development of the equations had 10 or more years of record and include active and discontinued continuous-record and crest-stage partial-record streamflow-gaging stations. Regional regression equations were developed for flood flows expected every 10, 25, 50, 100, and 500 years by the use of a weighted multiple linear regression model. The State was divided into two regions. The largest region, Region A, encompasses about 78 percent of Pennsylvania. The smaller region, Region B, includes only the northwestern part of the State. Basin characteristics used in the regression equations for Region A are drainage area, percentage of forest cover, percentage of urban development, percentage of basin underlain by carbonate bedrock, and percentage of basin controlled by lakes, swamps, and reservoirs. Basin characteristics used in the regression equations for Region B are drainage area and percentage of basin controlled by lakes, swamps, and reservoirs. The coefficient of determination (R 2 ) values for the five flood-frequency equations for Region A range from 0.93 to 0.82, and for Region B, the range is from 0.96 to 0.89. While the regression equations can be used to predict the magnitude and frequency of peak flows for most streams in the State, they should not be used for streams with drainage areas greater than 2,000 square miles or less than 1.5 square miles, for streams that drain extensively mined areas, or for stream reaches immediately below flood-control reservoirs. In addition, the equations presented for Region B should not be used if the stream drains a basin with more than 5 percent urban development.

Water-Resources Investigations Report↗
USGS2012

Lake sturgeon population attributes and reproductive structure in the Namakan Reservoir, Minnesota and Ontario

Quantified were the age, growth, mortality and reproductive structure of lake sturgeon ( Acipenser fulvescens ) collected in the US and Canadian waters of the Namakan Reservoir. The hypotheses were tested that (i) age and growth of lake sturgeon in the Namakan Reservoir would differ by sex and reproductive stage of maturity, and (ii) that the relative strength of year-classes of lake sturgeon in the reservoir would be affected by environmental variables. To quantify age, growth and mortality of the population, existing data was used from a multi-agency database containing information on all lake sturgeon sampled in the reservoir from 2004 to 2009. Lake sturgeon were sampled in the Minnesota and Ontario waters of the Namakan Reservoir using multi-filament gillnets 1.8 m high and 30–100 m long and varying in mesh size from 178 to 356 mm stretch. Reproductive structure of the lake sturgeon was assessed only during spring 2008 and 2009 using plasma testosterone and estradiol-17β concentrations. Ages of lake sturgeon >75 cm ranged from 9 to 86 years (n = 533, mean = 36 years). A catch-curve analysis using the 1981–1953 year classes estimated total annual mortality of adults to be 4.8% and annual survival as 95.2%. Using logistic regression analysis, it was found that total annual precipitation was positively associated with lake sturgeon year-class strength in the Namakan Reservoir. A 10 cm increase in total annual precipitation was associated with at least a 39% increase in the odds of occurrence of a strong year class of lake sturgeon in the reservoir. Plasma steroid analysis revealed a sex ratio of 2.4 females: 1 male and, on average, 10% of female and 30% of male lake sturgeon were reproductively mature each year (i.e. potential spawners). Moreover, there was evidence based on re-captured male fish of both periodic and annual spawning, as well as the ability of males to rapidly undergo gonadal maturation prior to spawning. Knowledge of lake sturgeon reproductive structure and factors influencing recruitment success contribute to the widespread conservation efforts for this threatened species.

Minnesota, Ontario↗
USGS1986

Water resources inventory of Connecticut Part 9: Farmington River basin

The Farmington River basin covers 435 square miles in north-central Connecticut upstream from Tariffville and downstream of the Massachusetts state line. Most water in the basin is derived from precipitation, which averages 48 inches (366 billion gallons) per year. An additional 67 billion gallons of water per year enters the basin from Massachusetts in the West Branch of the Farmington River, Hubbard River, Valley Brook and some smaller streams. Of the total 433 billion gallons, 174 billion gallons returns to the atmosphere through evaporation and transpiration. 239 billion gallons flows out of the study area in the Farmington River at Tariffville, and 20 billion gallons is diverted for Hartford water supply. Variations in streamflow at 23 continuous-record gaging stations are summarized in standardized graphs and tables that can be used to estimate streamflow characteristics at other sites. For example, mean flow and low-flow characteristics such as the 7-day annual minimum flow for 2-year and 10-year recurrence intervals, have been determined for many partial-record stations from the data for the 23 continuous-record stations. Of the 31 principal lakes, ponds, and reservoirs in the basin, eight have usable storage capacities of more than 1 billion gallons. Two of the largest, Colebrook River Lake and Barkhamsted Reservoir, have more than 30 billion gallons usable storage. Floods have occurred in the area in every month of the year. The greatest known flood on the Farmington River was in August 1955, which had a peak flow of 140,000 cubic feet per second at Collinsville. Since then, three major floodcontrol reservoirs have been constructed to reduce the hazards of high streamflow. The major aquifers underlying the basin are composed of unconsolidated materials (stratified drift and till) and bedrock (sedimentary, igneous, and metamorphic). Stratified drift overlies till and bedrock in valleys and lowlands; it averages about 90 feet in thickness, and is capable of large sustained yields of water to individual wells. Based on hydrologic characteristics and available recharge, sixteen stratified-drift areas are selected as the most favorable for large-scale development. Potential yields can be estimated by several methods. Small water supplies can be obtained from all aquifers. Wells in bedrock yield at least one to two gallons per minute at most sites. The probability of adequate yields for domestic supply is greater from sedimentary than from crystalline bedrock and is also greater from stratified-drift overburden than from till. The quality of water from all sources in the basin is good except where adversely affected by swamp drainage, aquifer composition or human activities. The water is generally low in dissolved-solids concentration and is soft to moderately hard. Surface water is less mineralized than ground water, especially during high-flow conditions when it is primarily direct runoff. Samples of water collected from 20 streams during high flow had 34 mg/L median dissolved-solids concentration and 16 mg/L median hardness. Samples collected from the same sites at low flow had 52 mg/L median dissolved solids and 28 mg/L median hardness. In contrast, water from wells had 112 mg/L median dissolved-solids concentration and 60 mg/L median hardness. Iron and manganese occur in objectionable concentrations ~n a few parts of the basin where streams drain swamps and aquifers are rich in iron- and manganese-bearing minerals. Five percent of streams at high flow, 21 percent at low flow, and 7 percent of ground-water samples contained iron in sufficient concentration to cause stains on plumbing fixtures and laundry. Human activities have modified the quality of water in parts of the basin. The high bacterial content of the Pequabuck River. and the high nitrate and chloride concentrations in some ground-water samples, are evidence of man’s influence. The quantity and quality of water in the basin’s streams and aquifers are satisfactory for a wide variety of uses. and, with suitable treatment, may be used for most purposes. The total amount of water used by 21 principal public supplies within the basin was 29 billion gallons in 1970. About 70 percent of this was used for domestic and commercial purposes, and nearly 30 percent was used by industry. Analyses of water from these systems show good quality.

Connecticut↗
USGS1999

Characterization and simulation of the quantity and quality of water in the Highland Lakes, Texas, 1983-92

The Highland Lakes, located in central Texas, are a series of seven reservoirs on the Colorado River (Lake Buchanan, Inks Lake, Lake Lyndon B. Johnson, Lake Marble Falls, Lake Travis, Lake Austin, and Town Lake). The reservoirs provide hydroelectric power for the area. In addition, Lake Austin and Town Lake also provide the public water supply for the Austin metropolitan area. Saline water released from Natural Dam Salt Lake during 1987–89 caused increased concern among water managers that high-salinity water entering the Highland Lakes could result in waterquality problems, necessitating additional treatment of the water. The maximum dissolved solids concentrations for the reservoirs after the saline inflow were about two to three times the average concentrations before the inflow. The maximum concentrations of chloride and sulfate after the inflow were about three to five times the average concentrations before the inflow. The concentrations of dissolved solids, chloride, and sulfate in Lake Buchanan, Inks Lake, Lake Lyndon B. Johnson, and Lake Marble Falls were less than the concentrations of the applicable water-quality standards by the end of 1990. Concentrations of these constituents in Lake Travis, Lake Austin, and Town Lake did not decrease to previous levels, which were less than the concentrations of the applicable waterquality standards, until the end of 1991. Constituent concentrations for Lake Buchanan and Inks Lake; for Lake Lyndon B. Johnson and Lake Marble Falls; and for Lake Travis, Lake Austin, and Town Lake were similar because of the relative storage capacities and location of tributary inflows. From the initial increase in constituent concentrations in Lake Buchanan (summer 1987) in response to the saline inflow, the high-salinity water passed through the entire Highland Lakes in about 3.5 years. A mathematical mass-balance model was used to simulate the input and movement of highsalinity water through the Highland Lakes and to estimate monthly mean concentrations of dissolved solids, chloride, and sulfate for wet, average, and dry hydrologic conditions. The simulated median monthly concentrations during the 10-year simulation period for each reservoir generally are larger for the average condition than for the wet condition and generally are larger for the dry condition than for the average condition. The simulated concentrations of dissolved solids, chloride, and sulfate decreased to levels less than the concentrations of the applicable water-quality standards in about 2 to 5 years after the saline water inflow of 1987–89 was simulated for the three hydrologic conditions. Results from the simulations indicate that saline inflows to the Highland Lakes similar to those of the releases from Natural Dam Salt Lake during 1987–89 are unlikely to cause large increases in future concentrations of dissolved solids, chloride, and sulfate in the Highland Lakes. The results also indicate that high-salinity water will continue to be diluted as it is transported downstream through the Highland Lakes, even during extended dry periods.

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