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Defining a data management strategy for USGS Chesapeake Bay studies

The mission of U.S. Geological Survey’s (USGS) Chesapeake Bay studies is to provide integrated science for improved understanding and management of the Chesapeake Bay ecosystem. Collective USGS efforts in the Chesapeake Bay watershed began in the 1980s, and by the mid-1990s the USGS adopted the watershed as one of its national place-based study areas. Great focus and effort by the USGS have been directed toward Chesapeake Bay studies for almost three decades. The USGS plays a key role in using “ecosystem-based adaptive management, which will provide science to improve the efficiency and accountability of Chesapeake Bay Program activities” (Phillips, 2011). Each year USGS Chesapeake Bay studies produce published research, monitoring data, and models addressing aspects of bay restoration such as, but not limited to, fish health, water quality, land-cover change, and habitat loss. The USGS is responsible for collaborating and sharing this information with other Federal agencies and partners as described under the President’s Executive Order 13508—Strategy for Protecting and Restoring the Chesapeake Bay Watershed signed by President Obama in 2009. Historically, the USGS Chesapeake Bay studies have relied on national USGS databases to store only major nationally available sources of data such as streamflow and water-quality data collected through local monitoring programs and projects, leaving a multitude of other important project data out of the data management process. This practice has led to inefficient methods of finding Chesapeake Bay studies data and underutilization of data resources. Data management by definition is “the business functions that develop and execute plans, policies, practices and projects that acquire, control, protect, deliver and enhance the value of data and information.” (Mosley, 2008a). In other words, data management is a way to preserve, integrate, and share data to address the needs of the Chesapeake Bay studies to better manage data resources, work more efficiently with partners, and facilitate holistic watershed science. It is now the goal of the USGS Chesapeake Bay studies to implement an enhanced and all-encompassing approach to data management. This report discusses preliminary efforts to implement a physical data management system for program data that is not replicated nationally through other USGS databases.

Chesapeake Bay

Ground-water quality in Quaternary deposits of the central High Plains aquifer, south-central Kansas, 1999

Water samples from 20 randomly selected domestic water-supply wells completed in the Quaternary deposits of south-central Kansas were collected as part of the High Plains Regional Ground-Water Study conducted by the U.S. Geological Survey's National Water-Quality Assessment Program. The samples were analyzed for about 170 water-quality constituents that included physical properties, dissolved solids and major ions, nutrients and dissolved organic carbon, trace elements, pesticides, volatile organic compounds, and radon. The purpose of this study was to provide a broad overview of ground-water quality in a major geologic subunit of the High Plains aquifer. Water from five wells (25 percent) exceeded the 500-milligrams-per-liter of dissolved solids Secondary Maximum Contaminant Level for drinking water. The Secondary Maximum Contaminant Levels of 250 milligrams per liter for chloride and sulfate were exceeded in water from one well each. The source of these dissolved solids was probably natural processes. Concentrations of most nutrients in water from the sampled wells were small, with the exception of nitrate. Water from 15 percent of the sampled wells had concentrations of nitrate greater than the 10-milligram-per-liter Maximum Contaminant Level for drinking water. Water from 80 percent of the sampled wells showed nitrate enrichment (concentrations greater than 2.0 milligrams per liter), which is more than what might be expected for natural background concentrations. This enrichment may be the result of synthetic fertilizer applications, the addition of soil amendment (manure) on cropland, or livestock production. Most trace elements in water from the sampled wells were detected only in small concentrations, and few exceeded respective water-quality standards. Only arsenic was detected in one well sample at a concentration (240 micrograms per liter) that exceeded its proposed Maximum Contaminant Level (5.0 micrograms per liter). Additionally, one concentration of iron and two concentrations of manganese were larger than the Secondary Maximum Contaminant Levels of 300 and 50 micrograms per liter, respectively. Some occurrences of trace elements may have originated from human-related sources; however, the generally small concentrations that were measured probably reflect mostly natural sources for these constituents. A total of 47 pesticide compounds from several classes of herbicides and insecticides that included triazine, organophosphorus, organochlorine, and carbamate compounds and three pesticide degradation products were analyzed in ground-water samples during this study. Water from 50 percent of the wells sampled had detectable concentrations of one or more of these 47 compounds. The herbicide atrazine and its degradation product deethylatrazine were detected most frequently (in water from eight and nine wells, respectively); other pesticides detected were the insecticides carbofuran (in water from one well) and diazinon (in water from one well), and the herbicide metolachlor (in water from two wells). However, all concentrations of these compounds were small and substantially less than established Maximum Contaminant Levels. The use of pesticides in crop production probably is largely responsible for the occurrence of pesticides in the ground-water samples collected during this study. Although concentrations of detected pesticides were small (relative to established Maximum Contaminant Levels), the synergistic effect of these concentrations and long-term exposure to multiple pesticides on human health are unknown. Water samples from the Quaternary deposits were analyzed for 85 volatile organic compounds. Water from two wells (10 percent) had a detectable concentration of a volatile organic compound. Chloroform was detected at concen-trations of 0.18 and 0.25 microgram per liter, substantially less than the 100-microgram-per-liter Maximum Contaminant Level for total trihalomethanes. In general, the occurrence and detectio

Water-Resources Investigations Report

Presence of selected chemicals of emerging concern in water and bottom sediment from the St. Louis River, St. Louis Bay, and Superior Bay, Minnesota and Wisconsin, 2010

The St. Louis Bay of Lake Superior receives substantial urban runoff, wastewater treatment plant effluent, and industrial effluent. In 1987, the International Joint Commission designated the St. Louis Bay portion of the lower St. Louis River as one of the Great Lakes Areas of Concern. Concerns exist about the potential effects of chemicals of emerging concern on aquatic biota because many of these chemicals, including endocrine active chemicals, have been shown to affect the endocrine systems of fish. To determine the occurrence of chemicals of emerging concern in the St. Louis River, the St. Louis Bay, and Superior Bay, the U.S. Geological Survey in cooperation with the Minnesota Pollution Control Agency and the Wisconsin Department of Natural Resources collected water and bottom-sediment samples from 40 sites from August through October 2010. The objectives of this study were to (1) identify the extent to which chemicals of emerging concern, including pharmaceuticals, hormones, and other organic chemicals, occur in the St. Louis River, St. Louis Bay, and Superior Bay, and (2) identify the extent to which the chemicals may have accumulated in bottom sediment of the study area. Samples were analyzed for selected wastewater indicators, hormones, sterols, bisphenol A , and human-health pharmaceuticals. During this study, 33 of 89 chemicals of emerging concern were detected among all water samples collected and 56 of 104 chemicals of emerging concern were detected in bottom-sediment samples. The chemical N,N -diethyl- meta -toluamide (DEET) was the most commonly detected chemical in water samples and 2,6-dimethylnaphthalene was the most commonly detected chemical in bottom-sediment samples. In general, chemicals of emerging concern were detected at a higher frequency in bottom-sediment samples than in water samples. Estrone (a steroid hormone) and hexahydrohexamethyl cyclopentabensopyran (a synthetic fragrance) were the most commonly detected endocrine active chemicals in water samples; beta -sitosterol (a plant sterol), estrone, and 4- tert -octylphenol (an alkylphenol) were the most commonly detected endocrine active chemicals in bottom-sediment samples. The greater detection frequency of chemicals in bottom-sediment samples compared to the detection frequency in water samples indicates that bottom sediment is an important sink for chemicals of emerging concern. At least one polycyclic aromatic hydrocarbon was detected in every sample; and in most samples, all nine polycyclic aromatic hydrocarbons included in analyses were detected. Bottom sediment collected from Superior Bay had the most polycyclic aromatic hydrocarbon detections of the sediment sampling locations.

Minnesota;Wisconsin

Feeling the sting? Addressing land-use changes can mitigate bee declines

Pollinators are an essential component of functioning and sustainable agroecosystems. Despite their critical economic and ecological role, wild and managed bees are declining throughout the United States and across the globe. Commercial beekeepers lost nearly 40.5% of their colonies in 2015–2016 and estimated wild bee abundance declined 23% between 2008 and 2013. These losses are due to a number of factors—including parasites, pesticides, and pathogens—but one key driver is the loss of habitat and floral resources necessary for pollinator survival. Here, we trace how land-use changes, and the policies and land management practices behind them, have played a role in diminishing floral resources and provide steps that can be taken to mitigate forage and habitat loss due to land-use changes. By addressing land-use changes and their drivers, considerable progress can be made toward mitigating bee declines and achieving national goals for pollinator health.

Alberta, Iowa, Manitoba, Minnesota, Montana, North

Mercury speciation and microbial transformations in mine wastes, stream sediments, and surface waters at the Almaden Mining District, Spain

Speciation of Hg and conversion to methyl-Hg were evaluated in mine wastes, sediments, and water collected from the Almade??n District, Spain, the world's largest Hg producing region. Our data for methyl-Hg, a neurotoxin hazardous to humans, are the first reported for sediment and water from the Almade??n area. Concentrations of Hg and methyl-Hg in mine waste, sediment, and water from Almade??n are among the highest found at Hg mines worldwide. Mine wastes from Almade??n contain highly elevated Hg concentrations, ranging from 160 to 34 000 ??g/g, and methyl-Hg varies from <0.20 to 3100 ng/g. Isotopic tracer methods indicate that mine wastes at one site (Almadenejos) exhibit unusually high rates of Hg-methylation, which correspond with mine wastes containing the highest methyl-Hg concentrations. Streamwater collected near the Almade??n mine is also contaminated, containing Hg as high as 13 000 ng/L and methyl-Hg as high as 30 ng/L; corresponding stream sediments contain Hg concentrations as high as 2300 ??g/g and methyl-Hg concentrations as high as 82 ng/g. Several streamwaters contain Hg concentrations in excess of the 1000 ng/L World Health Organization (WHO) drinking water standard. Methyl-Hg formation and degradation was rapid in mines wastes and stream sediments demonstrating the dynamic nature of Hg cycling. These data indicate substantial downstream transport of Hg from the Almade??n mine and significant conversion to methyl-Hg in the surface environment.

Environmental Science & Technology

Occurrence of herbicides, nitrite plus nitrate, and selected trace elements in ground water from northwestern and northeastern Missouri, July 1991 and 1992

The U.S. Geological Survey and the Missouri Department of Health collected water samples for analysis of nitrite plus nitrate and herbicides from rural domestic wells in northwestern and northeastern Missouri in 1991 and 1992. In July 1991, samples were collected from 130 wells in Caldwell, Clinton, Daviess, Gentry, and Nodaway Counties in northwestern Missouri. Nitrite plus nitrate concentrations as nitrogen ranged from less than 0.05 to 63 milligrams per liter. Nitrite plus nitrate concentrations exceeded the State drinking-water standard of 10 milligrams per liter in water samples from 28 wells. One or more of the herbicides--alachlor, atrazine, cyanazine; metribuzin, metolachlor, and trifluralin--were detected at concentrations greater than or equal to 0.05 micrograms per liter in 19 samples. Atrazine was detected in water samples from 16 wells. In July 1992, water samples were collected from 147 wells in Audrain, Clark, Lewis, Monroe, Scotland, and Shelby Counties in northeastern Missouri. Nitrite plus nitrate as nitrogen concentrations in samples ranged from less than 0.05 to 60 milligrams per liter and exceeded 10 milligrams per liter in samples from 28 wells. One or more of the herbicides-alachlor, atrazine, cyanazine, metribuzin, and metolachlor-were detected at concentrations greater than 0.10 microgram per liter in water samples from 19 of the wells sampled. Atrazine was detected in water from 18 wells.

Open-File Report

Assessment of ethylene dibromide, dibromochloropropane, other volatile organic compounds, radium isotopes, radon, and inorganic compounds in groundwater and spring water from the Crouch Branch and McQueen Branch aquifers near McBee, South Carolina, 2010-2012

Public-supply wells near the rural town of McBee, in southwestern Chesterfield County, South Carolina, have provided potable water to more than 35,000 residents throughout Chesterfield County since the early 1990s. Groundwater samples collected between 2002 and 2008 in the McBee area by South Carolina Department of Health and Environmental Control (DHEC) officials indicated that groundwater from two public-supply wells was characterized by the anthropogenic compounds ethylene dibromide (EDB) and dibromochloropropane (DBCP) at concentrations that exceeded their respective maximum contaminant levels (MCLs) established by the U.S. Environmental Protection Agency&rsquo;s (EPA) National Primary Drinking Water Regulations (NPDWR). Groundwater samples from all public-supply wells in the McBee area were characterized by the naturally occurring isotopes of radium-226 and radium-228 at concentrations that approached, and in one well exceeded, the MCL for the combined isotopes. The local water utility installed granulated activated carbon filtration units at the two EDB- and DBCP-contaminated wells and has, since 2011, shut down these two wells. Groundwater pumped by the remaining public-supply wells is currently (2014) centrally treated at a water-filtration plant. To assess the occurrence, distribution, and potential sources of the anthropogenic and naturally occurring compounds detected in groundwater in the McBee area, samples of groundwater and spring water were collected from public-supply, domestic-supply, agricultural-supply, and monitoring wells and springs, respectively, between 2010 and 2012 by the U.S. Geological Survey. The water samples were analyzed for concentrations of EDB, DBCP, other volatile organic compounds (VOCs), radium-226 and radium-228, radon, and inorganic compounds. All wells sampled were screened in the shallow Crouch Branch aquifer, the deeper McQueen Branch aquifer, or, for most public-supply wells, both aquifers. In areas where no wells existed or wells could not be installed, passive samplers that adsorb EDB, DBCP, and various VOCs, were installed in the shallow subsurface. A representative groundwater flow pathway to each public supply well and selected other wells was determined by using a calibrated three-dimensional groundwater-flow model of the Atlantic Coastal Plain in Chesterfield County and particle-tracking analysis. The aerial extent of the groundwater flow pathway to public-supply wells was mapped by using chlorofluorocarbon-concentration based, apparent-age dates of the groundwater. The water-quality data collected between 2010 and 2012, in conjunction with groundwater flow pathways and historical aerial photographs of land uses near McBee, indicate an area where EDB-, DBCP-, 1,2-dichloropropane-, 1,3-dichloropropane-, and carbon disulfide-contaminated groundwater exists in the Crouch Branch aquifer in the Cedar Creek Basin and north of McBee and is most likely related to the past use of these compounds between the early 1900s and the 1980s as soil fumigants in predominately agricultural areas north of McBee. The highest EDB concentration detected (18.6 micrograms per liter) during the 3-year study was in a groundwater sample from an agricultural-supply well located north of McBee. Other VOCs, such as dichloromethane and 1,1,2-trichloroethane, also were detected in groundwater samples from this EDB-contaminated agricultural-supply well but are from unknown source(s). The fact that the agricultural area north of McBee is located in a recharge area for the Crouch Branch aquifer most likely facilitated the groundwater contamination in this area. DBCP-contaminated groundwater detected in three public-supply wells south of McBee in the deeper McQueen Branch aquifer appears to be related to past soil fumigation practices that used DBCP in agricultural areas located south of McBee. One of the three DBCP-contaminated public-supply wells also contained EDB, most likely present in groundwater due to the release of leaded gasolines that contained EDB as a fuel additive between the 1940s and 1970s. A gasoline-source of EDB, rather than a soil-fumigation source, is supported by the co-detection in groundwater from the well of 1,2-dichloroethane, a lead scavenger compound also added to leaded gasoline. Groundwater pumped from two public-supply wells located within and to the east of the McBee town limits and one domestic-supply well east of McBee was characterized by the detection of 1,1-dichloroethane, trichloroethylene, 1,1-dichloroethylene, and perchloroethylene. Groundwater flow pathways determined for these wells indicate that the potential source(s) of these compounds detected in one public-supply well and the domestic-supply well may be located within the McBee town limits, and that the potential source(s) of these compounds detected in the public-supply well to the east of McBee may be located in an area north of McBee formerly used for agriculture, but used for industry since at least the 1970s. Radium isotopes (defined in this study as the sum of radium-226 and radium-228 concentrations) and radon were detected in all wells sampled in the McBee area between 2010 and 2012. Wells characterized by radium isotope concentrations in groundwater that exceeded the MCL of 5.0 picocuries per liter were also characterized by specific conductance values greater than 30 microsiemens per centimeter and clustered north of McBee in a predominately agricultural area, and in agricultural and urban areas located within and east of McBee. The elevated specific conductance values measured in groundwater from these wells most likely are due to recharge by water mineralized by fertilizer application in agricultural areas, or due to the recharge by water mineralized by septic-tank drain-field effluent near urban areas. Radon was detected in groundwater from all wells sampled, and radon concentrations in groundwater from three monitoring wells exceeded the proposed MCL of 300 picocuries per liter. Concentrations of uranium in groundwater in the McBee area increased with increased groundwater-sample depth, most likely due to the proximity of the sample-collection location to basement rock that contains uranium-bearing minerals.

South Carolina

National water summary 1986: Hydrologic events and ground-water quality

Ground water is one of the most important natural resources of the United States and degradation of its quality could have a major effect on the welfare of the Nation. Currently (1985), ground water is the source of drinking water for 53 percent of the Nation's population and for more than 97 percent of its rural population. It is the source of about 40 percent of the Nation's public water supply, 33 percent of water for irrigation, and 17 percent of freshwater for selfsupplied industries. Ground water also is the source of about 40 percent of the average annual streamflow in the United States, although during long periods of little or no precipitation, ground-water discharges provide nearly all of the base streamflow. This hydraulic connection between aquifers and streams implies that if a persistent pollutant gets into an aquifer, it eventually could discharge into a stream. Information presented in the 1986 National Water Summary clearly shows that the United States has very large amounts of potable ground water available for use. Although naturally occurring constituents, such as nitrate, and human-induced substances, such as synthetic organic chemicals, frequently are detected in ground water, their concentrations usually do not exceed existing Federal or State standards or guidelines for maximum concentrations in drinking water. Troublesome contamination of ground water falls into two basic categories related to the source or sources of the contamination. Locally, high concentrations of a variety of toxic metals, organic chemicals, and petroleum products have been detected in ground water associated with point sources such as wastedisposal sites, storage-tank leaks, and hazardous chemical spills. These types of local problems commonly occur in densely populated urban areas and industrialized areas. Larger, multicounty areas also have been identified where contamination frequently is found in shallow wells. These areas generally are associated with broad-scale, or nonpoint, sources of contamination such as agricultural activities or highdensity domestic waste disposal (septic systems) in urban centers. At present, only a very small percentage of the total volume of potable ground water in the United States is contaminated from both point and nonpoint sources; however, available data, especially data about the occurrence of synthetic organic and toxic substances, generally are inadequate to determine the full extent of ground-water contamination in the Nation's aquifers or to define trends in groundwater quality. Most information about the occurrence of these substances has come from the study of individual sites or areas where contamination had already been detected or suspected. Management and protection of ground water present a major challenge to the Nation. Current and projected costs of detection and cleanup of existing ground-water contamination are staggering and, even so, complete removal of pollutants from ground water in the vicinity of some waste sites might not be technically feasible. At all levels of government, the task of protecting the resource for its most beneficial uses is difficult and controversial. Despite increasing awareness that some of the Nation's ground water is contaminated with a variety of toxic metals, synthetic organic chemicals, radionuclides, pesticides, and other contaminants that might present a long-term risk to human health, public policy towards ground-water protection is still in the formative stages. Despite increasing efforts devoted to ground-water protection by State and Federal regulatory and resource-management agencies, the extent of ground-water contamination is likely to appear to increase over the next few years because more agencies will be searching for evidence of contamination, and they will be using increasingly sensitive analytical procedures. Increased technology and expanded monitoring activities probably will detect the effects of past contamination and land uses on water quality. The significant time lag between a waterquality change in one part of an aquifer system and the effects of that change at a downgradient site, such as a well, results from the generally slow movement of ground water. This lag between cause and observed effect needs to be considered in evaluating the effectiveness of current and future ground-water policies and remedial measures. Conclusive answers to questions about the location, extent, and severity of ground-water contamination, and about trends in ground-water quality, must await further collection and analysis of data from the Nation's aquifers. Generalizations, however, can be made, and the 1986 National Water Summary, which describes the natural quality of ground-water resources in each State and the major contamination problems that have been identified as of 1986, provides a national perspective of the ground-water-quality situation. The 1986 National Water Summary follows the format of previous volumes. It contains three parts, and the contents of each of these parts are highlighted below.

Water Supply Paper

Hydrogeology and Extent of Saltwater Intrusion in the Northern Part of the Town of Oyster Bay, Nassau County, New York: 1995–98

The Oyster Bay study area, in the northern part of Nassau County, N.Y., is underlain by unconsolidated deposits that form a sequence of aquifers and confining units. At least one production well has been affected by the intrusion of saltwater from Hempstead Harbor, Long Island Sound, and Cold Spring Harbor. Nineteen boreholes were drilled during 1995-98 for the collection of hydrogeologic, geochemical, and geophysical data to delineate the subsurface geology and the extent of saltwater intrusion. Continuous high-resolution marine-seismic-reflection surveys in the surrounding embayments of the Oyster Bay study area were conducted in 1996. New drill-core data indicate two hydrogeologic units—the North Shore aquifer and the North Shore confining unit—where the Lloyd aquifer, the Raritan confining unit, and the Magothy aquifer have been completely removed by glacial erosion. Water levels at 95 observation wells were measured quarterly during 1995–98. These data and continuous water-level records indicated that (1) the upper glacial (water-table) and Magothy aquifers are hydraulically connected and that their water levels did not respond to tidal fluctuations, and (2) the Lloyd and North Shore aquifers are hydraulically connected and their water levels responded to pumping and to tidal fluctuations. Marine seismic-reflection surveys in the surrounding embayments indicate at least four glacially eroded buried valleys with subhorizontal, parallel reflectors indicative of draped bedding that is interpreted as infilling by silt and clay. The buried valleys (1) truncate the surrounding coarse-grained deposits, (2) are asymmetrical and steep sided, (3) trend northwest-southeast, (4) are several miles long and about 1 mile wide, and (5) extend to more than 500 feet below sea level. Water samples taken during 1995–98 from three production wells and six observation wells screened in the upper glacial and Magothy aquifers contained volatile organic compounds in concentrations that exceeded the New York State Department of Health Drinking Water Maximum Contaminant Levels. High iron or nitrate concentrations were detected in water samples taken in 1997–98 from 39 observation wells. Previous high concentrations resulted in the shutdown of two production wells. Four distinct areas of saltwater intrusion in the Oyster Bay study area were delineated—three were in the upper glacial aquifer, and the fourth was in the Lloyd aquifer. Borehole-geophysical-logging data indicated that three of these saltwater "wedges" ranged from a few feet thick to more than 100 feet thick and had sharp freshwater-saltwater interfaces. Chloride concentrations in water from eight observation wells within these wedges in 1997 ranged from 125 to 13,750 milligrams per liter. One production well in Bayville has been shut down as of 1996 and others in the area may be affected by these saltwater wedges.

New York

Phosphorus loads entering Long Pond, a small embayment of Lake Ontario near Rochester, New York

Introduction Long Pond is one of many small, shallow embayments along the southern edge of Lake Ontario (fig. 1). These embayments are an important recreational resource and wildlife habitat; thus, maintaining their natural state is essential to their continued use. In recent decades, Long Pond and the adjacent Cranberry Pond have become hypereutrophic (overly enriched with nutrients) (Makarewicz and others, 1990) as a result of nitrogen and phosphorus transported to those waters by Northrup Creek from sources within the drainage basin. In 1989, the Monroe County Department of Health and the Town of Greece, in cooperation with the U.S. Geological Survey (USGS), began a water-quality-monitoring program on Northrup Creek near North Greece at a site of a gaging station about 5 mi north (downstream) of the Village of Spencerport and the Spencerport wastewater-treatment plant. The program included the collection of water samples from October 1989 through September 1998 for chemical analysis and the collection of streamflow data for use in calculating phosphorus loads at the site. This fact sheet addresses the issue of concentration and loads of phosphorus in Northrup Creek, the principal tributary to Long Pond. Northrup Creek begins just south of the Village of Spencerport in Monroe County and flows northward into Long Pond. It drains a total of 23.5 mi2 in the towns of Ogden, Parma, and Greece (fig. 1). The drainage basin contains agricultural land, housing developments, and a small amount of urban land (table 1).

New York

Updates to the Madison Lake (Minnesota) CE–QUAL–W2 water-quality model for assessing algal community dynamics

A previously developed CE–QUAL–W2 model for Madison Lake, Minnesota, simulated the algal community dynamics, water quality, and fish habitat suitability of Madison Lake under recent (2014) meteorological conditions. Additionally, this previously developed model simulated the complex interplay between external nutrient loading, internal nutrient loading from sediment release of phosphorus, and the organic matter decomposition of the algal biomass. However, the partitioning of Cyanophyta within the modeling framework was simplified to one group and did not account for how different Cyanophyta populations are affected by light conditions, use of nitrogen, temperature growth ranges, and differences in settling rates. Properly capturing Cyanophyta dynamics is important given the potential risks posed by potential large algal blooms. For example, when Cyanophyta form large blooms, recreational activities can become restricted in certain areas because of thick algal scums or algal mats, in addition to the possible production of a class of toxins, known as cyanotoxins, capable of threatening human health, domestic animals, and wildlife. Therefore, we updated the model to partition the Cyanophyta into a group that fixed nitrogen and a second, more buoyant Cyanophyta group that did not independently fix nitrogen. The U.S. Geological Survey, in cooperation with the St. Croix Watershed Research Station (Science Museum of Minnesota) with support from the Environmental and Natural Resources Trust Fund of Minnesota (Legislative-Citizen Commission on Minnesota Resources), updated the Madison Lake CE–QUAL–W2 model to address the shortcomings of simulating Cyanophyta in the previously developed model and better characterize Cyanophyta into two groups. In addition to updating the Cyanophyta group differentiation, the part of the model that handles the simulation of algal community dynamics was updated while preserving model predictive capabilities for nutrients, water temperature, and dissolved oxygen. The calibration and validation of the model was done under recent meteorological conditions with large and persistent Cyanophyta blooms (2014 and 2016). Overall, the model simulations predicted the persistently large total phosphorus concentrations in the hypolimnion of Madison Lake and key differences in nutrient concentrations between 2014 and 2016. The Cyanophyta bloom persistence throughout the summer was also simulated by the model in 2014 and 2016, a critical goal of the model update. Finally, monthly total phosphorus budgets were calculated for the updated Madison Lake model for 2014 and 2016.

Minnesota

Highly pathogenic avian influenza virus exposure and infection in free-ranging bobcats (Lynx rufus) in New York, USA

Highly pathogenic H5N1 influenza A virus (HP H5N1) cases in wild mammals have been increasing globally. Carnivora has been the most affected mammal order; however, the extent of morbidity and mortality in carnivores exposed to HP H5N1 remains undefined. We assessed the presence of antibodies to H5 and N1 in the sera of 16 live-captured bobcats ( Lynx rufus ) in New York State, USA; reported on postcapture outcomes of HP H5N1-exposed bobcats; and reported on a case of HP H5N1 infection in one bobcat. In 2024, 4/16 bobcats (25%) tested positive for antibodies to H5 and N1. Two bobcats were confirmed alive as of November 2024 according to GPS data; the other two were alive as of June 2024, when their GPS collars stopped communicating. Another bobcat, which was negative for HP H5N1 antibodies at capture, died from HP H5N1 infection within 5 wks of capture. Our results provide evidence of bobcats both surviving and succumbing to HP H5N1 infection and highlight the importance of focused health studies paired with monitoring data to better understand exposure, infection, and outcomes for novel pathogens and species.

New York

Occurrence of cyanazine compounds in groundwater: Degradates more prevalent than the parent compound

A recently developed analytical method using liquid chromatography/mass spectrometry was used to investigate the occurrence of cyanazine and its degradates cyanazine acid (CAC), cyanazine amide (CAM), deethylcyanazine (DEC), and deethylcyanazine acid (DCAC) in groundwater. This research represents some of the earliest data on the occurrence of cyanazine degradates in groundwater. Although cyanazine was infrequently detected in the 64 wells across Iowa sampled in 1999, cyanazine degradates were commonly found during this study. The most frequently detected cyanazine compound was DCAC (32.8%) followed by CAC (29.7%), CAM (17.2%), DEC (3.1%), and cyanazine (3.1%). The frequency of detection for cyanazine or one or more of its degradates (CYTOT) was more than 12-fold over that of cyanazine alone (39.1% for CYTOT versus 3.1% for cyanazine). Of the total measured concentration of cyanazine, only 0.2% was derived from its parent compound - with DCAC (74.1%) and CAC (18.4%) comprising 92.5% of this total. Thus, although DCAC and CAC had similar frequencies of detection, DCAC was generally present in higher concentrations. No concentrations of cyanazine compounds for this study exceeded water-quality criteria for the protection of human health. Only cyanazine, however, has such a criteria established. Nevertheless, because these cyanazine degradates are still chlorinated, they may have similar toxicity as their parent compound - similar to what has been found with the chlorinated degradates of atrazine. Thus, the results of this study documented that data on the degradates for cyanazine are critical for understanding its fate and transport in the hydrologic system. Furthermore, the prevalence of the chlorinated degradates of cyanazine found in groundwater suggests that to accurately determine the overall effect on human health and the environment from cyanazine its degradates should also be considered. In addition, because CYTOT was found in 57.6% of the samples collected from alluvial aquifers, about 2-5 times more frequently than the other major aquifer types (glacial drift, bedrock/karst, bedrock/nonkarst) under investigation, this finding has long-term implications for the occurrence of CYTOT in streams. It is anticipated that low-level concentrations of CYTOT will continue to be detected in streams for years after the use of cyanazine has terminated (scheduled for the year 2000 in the United States), primarily through its movement from groundwater into streams during base-flow conditions.

Iowa

Methods for comparing water-quality conditions among National Water-Quality Assessment Study Units, 1992-1995

The National Water-Quality Assessment is based on intensive investigations of stream and ground-water quality in selected major hydrologic basins (study units) of the United States. One objective of the national assessment is to comparatively evaluate water-quality conditions within and among the different study units. Methods were developed to compare the water-quality conditions of 20 study units that were studied during 1992-1995. Two approaches were taken: (1) water-quality conditions for each study unit were ranked in relation to the findings for all study units, and (2) water-quality conditions for each study unit were compared to established criteria for the protection of human health and aquatic life. Separate rankings were developed for several major characteristics of water quality by using selected combinations of measured values for individual constituents or properties. The water-quality characteristics that were evaluated for streams were nutrients and pesticides in water, organochlorine pesticides and polychlorinated biphenyls in bed sediment and tissue, semivolatile organic compounds and trace elements in bed sediment, fish community degradation, and stream habitat degradation. The water-quality characteristics that were evaluated for ground water were nitrate, pesticides, volatile organic compounds, dissolved solids, and radon. The water-quality rankings are relative strictly to the distribution of conditions measured at sampling sites included in developing the method. Sites in the first 20 National Water-Quality Assessment study units include a broad range of environmental settings, but are not a statistically representative sample of the Nation. > To supplement the relative rankings, established water-quality criteria were used to indicate where particular constituents may have adverse effects, and thus merit further investigation. Established water-quality criteria, which provide consistent benchmarks for national comparisons of individual constituents, were selected from a variety of sources and applied to specific constituents in the specific medium (water or sediment) appropriate for each criterion.

Open-File Report

Tracking toxins: A pilot investigation of cyanotoxins in north-central Tennessee’s surface waters and wells

Cyanobacterial toxins (cyanotoxins) threaten aquatic ecosystems and human health, yet the factors influencing their production and distribution in freshwater remain unclear. In north-central Tennessee, nutrient-rich runoff from agricultural and urban areas, combined with a karst landscape that supports drinking and recreational water use, heightens the need to understand cyanotoxin behavior. To examine cyanotoxin patterns, the U.S. Geological Survey and the Tennessee Department of Environment and Conservation monitored 18 sites, including two wells under the influence of surface water, every two weeks from September 2022 to November 2024. At least one cyanotoxin was detected at all sites, with the highest concentrations in deep reservoirs and lower levels in shallow systems. Most detections occurred during summer and fall, aligning with high temperatures and rapid-onset drought. Statistical analysis indicated that increased specific conductivity and pH raised the likelihood of detecting total microcystin, likely resulting from drought conditions and nutrient-laden runoff. Additionally, dissolved microcystin showed an inverse relationship with Cumberland River water levels, and principal component analysis showed that Secchi depth, chlorophyll a, pH, temperature, and conductivity explained most water quality variability. These results help increase understanding of cyanotoxin distribution and associated water quality conditions during detections to guide future freshwater cyanotoxin monitoring studies.

Tennessee

A fishery after the decline: The Susquehanna River Smallmouth Bass story

The Smallmouth Bass Micropterus dolomieu fishery in the Susquehanna River basin, Pennsylvania, is one of the most socioeconomically important fisheries in the region and has recently undergone considerable changes. These changes started in 2005, when disease was documented in young-of-the-year (age-0) Smallmouth Bass. Shortly thereafter, declines in abundance of both juveniles and adults were observed. These declines in abundance coincided with disease infections in age-0, intersex in adults, and concerns regarding contaminant exposure. Natural mortality rates, particularly for age-0, increased during this period (2005–2011), and there were concerns for the overall health of this world-class fishery. However, in recent years (2012–2017), there have been decreases in both mortality rates and external observations of disease and increases in abundance across multiple size-classes. Recent changes are encouraging for the future of the Smallmouth Bass fishery in the Susquehanna River. Yet, in light of the ever changing environmental, social, and anthropogenic influences on aquatic ecosystems, there remain concerns for Smallmouth Bass health and management. Because of this, ongoing research efforts are needed to monitor population and health changes and to conduct integrative research that considers complex relationships between organisms and their environments.

Pennsylvania

Select elements of concern in surface water of three hydrologic basins (Delaware River, Illinois River, and Upper Colorado River)—Data screening for the development of spatial and temporal models

The report focuses on the screening of previously published concentration data associated with 12 elements of concern (aluminum, arsenic, cadmium, chromium, copper, iron, mercury, manganese, lead, selenium, uranium, and zinc) measured in stream surface waters of three hydrologic basins (Delaware River Basin, Illinois River Basin, and the Upper Colorado River Basin). The purpose of this analysis is to determine what subsets of the original dataset (containing more than 1,500,000 observations) may be most suitable for each of two types of modeling efforts. The first type of modeling envisions a machine learning approach to determine which geospatial attributes are most significant in describing the spatial distribution of elemental concentrations within a basin. The second type of modeling envisions a stepwise regression approach to develop multivariable models that can be used to determine high resolution time-series estimates of elemental concentrations or loads at discrete U.S. Geological Survey real-time stream surface water sites. These site-specific temporal models are based on continuous measurements of available discharge and (or) in situ sensor data (temperature, pH, turbidity, dissolved oxygen, specific conductance, and (or) fluorescent dissolved organic matter) as the explanatory variables. The data screening for both model types considered historical trends in analytical methods and detection quantitation limits, the extent of censored data, data density, and environmental relevance with respect to three U.S. Environmental Protection Agency water quality thresholds (drinking water guidelines, human health criteria, and aquatic life criteria). The result of this analysis was the production of a final list of potential models deemed suitable for further development based upon the data exclusion (or inclusion) scheme developed herein for each model type. In both cases, the final models included mostly the three crustal elements (iron, manganese, and aluminum) that are found at comparatively high concentrations in surface water, whereas most of the more pernicious elements were excluded from the final model lists owing to various data limitations. The one exception to this was arsenic, for which the existing data were sufficient at three U.S. Geological Survey real-time sites for potential further development of time-series models.

Colorado, Delaware, Illinois, Indiana, Maryland, N

Evidence of weak contaminant-related oxidative stress in glaucous gulls (Larus hyperboreus) from the Canadian arctic

Environmental contaminants are transported over great distances to Arctic ecosystems, where they can accumulate in wildlife. Whether contaminant concentrations in wildlife are sufficient to produce adverse effects remains poorly understood. Exposure to contaminants elevates oxidative stress with possible fitness consequences. The glaucous gull ( Larus hyperboreus ), an Arctic top predator, was used as a bioindicator for investigating relationships between contaminant levels (organochlorines and polychlorinated biphenyls [OC/PCB], mercury [Hg], and selenium [Se]) and measures of oxidative stress (glutathione [GSH] metabolism and lipid peroxidation) in Canadian Arctic ecosystems. Contaminant levels were low and associations between contaminant exposure and oxidative stress were weak. Nevertheless, glutathione peroxidase activity rose with increasing hepatic Se concentrations, levels of thiols declined as Hg and OC/PCB levels rose, and at one of the two study sites levels of lipid peroxidation were elevated with increasing levels of hepatic Hg. These results suggest the possibility of a deleterious effect of exposure to contaminants on gull physiology even at low contaminant exposures.

Arctic