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USGS1995

Water-quality conditions at selected landfills in Mecklenburg County, North Carolina, 1986-92

Water-quality conditions at five municipal landfills in Mecklenburg County, North Carolina, were studied during 1986-92. Analytical results of water samples from monitoring wells and streams at and near the landfills were used to evaluate effects of leachate on surface and ground water. Ground-water levels at monitoring wells were used to determine directions of ground-water flow at the landfills. Data from previous studies were used for analysis of temporal trends in selected water-quality properties and chemical constituents. Effects of leachate, such as large biochemical- and chemical-oxygen demands, generally were evident in small streams originating within the landfills, whereas effects of leachate generally were not evident in most of the larger streams. In larger streams, surface-water quality upstream and downstream from most of the landfills was similar. However, the chemical quality of water in Irwin Creek appears to have been affected by the Statesville Road landfill. Concentrations of several constituents indicative of leachate were larger in samples collected from Irwin Creek downstream from the Statesville Road landfill than in samples collected from Irwin Creek upstream from the landfill. The effect of leachate on ground-water quality generally was largest in water from wells adjacent to waste-disposal cells. Concentrations of most constituents considered indicative of leachate generally were smaller with increasing distance from waste-disposal cells. Water samples from offsite wells generally indicated no effect or very small effects of leachate. Action levels designated by the Mecklenburg County Engineering Department and maximum contaminant levels established by the U.S. Environmental Protection Agency were exceeded in some samples from the landfills. Ground-water samples exceeded action levels and maximum contaminant levels more commonly than surface-water samples. Iron and manganese were the constituents that most commonly exceeded action levels in water samples from the landfills. Synthetic organic compounds were detected more commonly and in larger concentrations in ground-water samples than in surface-water samples. Concentrations of synthetic organic compounds detected in water samples from monitoring sites at the landfills generally were much less than maximum contaminant levels. However, concentrations of some chlorinated organic compounds exceeded maximum contaminant levels in samples from several monitoring wells at the Harrisburg Road and York Road landfills. Trend analysis indicated statistically significant temporal changes in concentrations of selected water-quality constituents and properties at some of the monitoring sites. Trends detected for the Holbrooks Road and Statesville Road landfills generally indicated an improvement in water quality and a decrease in effects of leachate at most monitoring sites at these landfills from 1979 to 1992. Water-quality trends detected for monitoring sites at the Harrisburg Road and York Road landfills, the largest landfills in the study, differed in magnitude and direction. Upward trends generally were detected for sites near recently closed waste-disposal cells, whereas downward trends generally were detected for sites near older waste-disposal cells. Temporal trends in water quality generally reflected changes in degradation processes associated with the aging of landfill wastes.

North Carolina↗

USGS2009

Applications of a broad-spectrum tool for conservation and fisheries analysis: Aquatic gap analysis

Natural resources support all of our social and economic activities, as well as our biological existence. Humans have little control over most of the physical, biological, and sociological conditions dictating the status and capacity of natural resources in any particular area. However, the most rapid and threatening influences on natural resources typically are anthropogenic overuse and degradation. In addition, living natural resources (i.e., organisms) do not respect political boundaries, but are aware of their optimal habitat and environmental conditions. Most organisms have wider spatial ranges than the jurisdictional boundaries of environmental agencies that deal with them; even within those jurisdictions, information is patchy and disconnected. Planning and projecting effects of ecological management are difficult, because many organisms, habitat conditions, and interactions are involved. Conservation and responsible resource use involves wise management and manipulation of the aspects of the environment and biological communities that can be effectively changed. Tools and data sets that provide new insights and analysis capabilities can enhance the ability of resource managers to make wise decisions and plan effective, long-term management strategies. Aquatic gap analysis has been developed to provide those benefits. Gap analysis is more than just the assessment of the match or mis-match (i.e., gaps) between habitats of ecological value and areas with an appropriate level of environmental protection (e.g., refuges, parks, preserves), as the name suggests. Rather, a Gap Analysis project is a process which leads to an organized database of georeferenced information and previously available tools to examine conservation and other ecological issues; it provides a geographic analysis platform that serves as a foundation for aquatic ecological studies. This analytical tool box allows one to conduct assessments of all habitat elements within an area of interest. Aquatic gap analysis naturally focuses on aquatic habitats. The analytical tools are largely based on specification of the species-habitat relations for the system and organism group of interest (Morrison et al. 2003; McKenna et al. 2006; Steen et al. 2006; Sowa et al. 2007). The Great Lakes Regional Aquatic Gap Analysis (GLGap) project focuses primarily on lotic habitat of the U.S. Great Lakes drainage basin and associated states and has been developed to address fish and fisheries issues. These tools are unique because they allow us to address problems at a range of scales from the region to the stream segment and include the ability to predict species specific occurrence or abundance for most of the fish species in the study area. The results and types of questions that can be addressed provide better global understanding of the ecological context within which specific natural resources fit (e.g., neighboring environments and resources, and large and small scale processes). The geographic analysis platform consists of broad and flexible geospatial tools (and associated data) with many potential applications. The objectives of this article are to provide a brief overview of GLGap methods and analysis tools, and demonstrate conservation and planning applications of those data and tools. Although there are many potential applications, we will highlight just three: (1) support for the Eastern Brook Trout Joint Venture (EBTJV), (2) Aquatic Life classification in Wisconsin, and (3) an educational tool that makes use of Google Earth (use of trade or product names does not imply endorsement by the U.S. Government) and Internet accessibility.

Gap Analysis Bulletin↗

USGS2009

Anthropogenic organic compounds in source water of selected community water systems that use groundwater, 2002-05

Source water, defined as groundwater collected from a community water system well prior to water treatment, was sampled from 221 wells during October 2002 to July 2005 and analyzed for 258 anthropogenic organic compounds. Most of these compounds are unregulated in drinking water and include pesticides and pesticide degradates, gasoline hydrocarbons, personal-care and domestic-use products, and solvents. The laboratory analytical methods used in the study have detection levels that commonly are 100 to 1,000 times lower than State and Federal standards and guidelines for protecting water quality. Detections of anthropogenic organic compounds do not necessarily indicate a concern to human health but rather help to identify emerging issues and track changes in occurrence and concentrations over time. Less than one-half (120) of the 258 compounds were detected in at least one source-water sample. Chloroform, in 36 percent of samples, was the most commonly detected of the 12 compounds that were in about 10 percent or more of source-water samples. The herbicides atrazine, metolachlor, prometon, and simazine also were among the commonly detected compounds. The commonly detected degradates of atrazine - deethylatrazine and deisopropylatrazine - as well as degradates of acetochlor and alachlor, generally were detected at concentrations similar to or greater than concentrations of the parent herbicide. The compounds perchloroethene, trichloroethene, 1,1,1-trichloroethane, methyl tert-butyl ether, and cis-1,2-dichloroethene also were detected commonly. The most commonly detected compounds in source-water samples generally were among those detected commonly across the country and reported in previous studies by the U.S. Geological Survey's National Water-Quality Assessment Program. Relatively few compounds were detected at concentrations greater than human-health benchmarks, and 84 percent of the concentrations were two or more orders of magnitude less than benchmarks. Five compounds (perchloroethene, trichloroethene, 1,2-dibromoethane, acrylonitrile, and dieldrin) were detected at concentrations greater than their human-health benchmark. The human-health benchmarks used for comparison were U.S. Environmental Protection Agency Maximum Contaminant Levels (MCLs) for regulated compounds and Health-Based Screening Levels developed by the U.S. Geological Survey in collaboration with the U.S. Environmental Protection Agency and other agencies for unregulated compounds. About one-half of all detected compounds do not have human-health benchmarks or adequate toxicity information to evaluate results in a human-health context. Ninety-four source-water and finished-water (water that has passed through all the treatment processes but prior to distribution) sites were sampled at selected community water systems during June 2004 to September 2005. Most of the samples were analyzed for compounds that were detected commonly or at relatively high concentrations during the initial source-water sampling. The majority of the finished-water samples represented water blended with water from one or more other wells. Thirty-four samples were from water systems that did not blend water from sampled wells with water from other wells prior to distribution. The comparison of source- and finished-water samples represents an initial assessment of whether compounds present in source water also are present in finished water and is not intended as an evaluation of water-treatment efficacy. The treatment used at the majority of the community water systems sampled is disinfection, which, in general, is not designed to remove the compounds monitored in this study. Concentrations of all compounds detected in finished water were less than their human-health benchmarks. Two detections of perchloroethene and one detection of trichloroethene in finished water had concentrations within an order of magnitude of the MCL. Concentrations of disinfection by-products were

Scientific Investigations Report↗

USGS2002

Ground-water quality in the central High Plains aquifer, Colorado, Kansas, New Mexico, Oklahoma, and Texas, 1999

A network of 74 randomly distributed domestic water-supply wells completed in the central High Plains aquifer was sampled and analyzed from April to August 1999 as part of the High Plains Regional Ground-Water Study conducted by the U. S. Geological Survey National Water-Quality Assessment Program to provide a broad-scale assessment of the ground-water-quality in this part of the High Plains aquifer. Water properties were relatively consistent across the aquifer, with water being alkaline and well oxidized. Water was mostly of the calcium and magnesium-bicarbonate type and very hard. Sulfate concentrations in water from three wells and chloride concentration in water from one well exceeded Secondary Maximum Contaminant Levels. Fluoride concentration was equal to the Maximum Contaminant Level in one sample. Nitrate concentrations was relatively small in most samples, with the median concentration of 2.3 milligrams per liter. Dissolved organic carbon concentration was relatively low, with a median concentration of 0.5 milligram per liter. The Maximum Contaminant Level set by the U.S. Environmental Protection Agency for nitrate as nitrogen of 10 milligrams per liter was exceeded by water samples from three wells. Most samples contained detectable concentrations of the trace elements aluminum, arsenic, barium, chromium, molybdenum, selenium, zinc, and uranium. Only a few samples had trace element concentrations exceeding Maximum Contaminant Levels. Fifty-five of the samples had radon concentrations exceeding the proposed Maximum Contaminant Level of 300 picocuries per liter. The greatest radon concentrations were detected where the Ogallala Formation overlies sandstones, shales and limestones of Triassic, Jurassic, or Cretaceous age. Volatile organic compounds were detected in 9 of 74 samples. Toluene was detected in eight of those nine samples. All volatile organic compound concentrations were substantially less than Maximum Contaminant Levels. Detections of toluene may have been artifacts of the sampling and analytical processes. Pesticides were detected in 18 of the 74 water samples. None of the pesticide concentrations exceeded Maximum Contaminant Levels. The most frequently detected pesticides were atrazine and its metabolite deethylatrazine, which were detected in water from 15 and 17 wells, respectively. Most of the samples with a detectable pesticide had at least two detectable pesticides. Six of the samples had more than two detectable pesticides. Tritium concentrations was greater than 0.5 tritium unit in 10 of 51 samples, indicating recent recharge to the aquifer. Twenty-one of the samples that had nitrate concentrations greater than 4.0 milligrams per liter were assumed to have components of recent recharge. Detection of volatile organic compounds was not associated with those indicators of recent recharge, with most of volatile organic compounds being detected in water from wells with small tritium and nitrate concentrations. Detection of pesticides was associated with greater tritium or nitrate concentrations, with 16 of the 18 wells producing water with pesticides also having tritium or nitrate concentrations indicating recent recharge.

Colorado, Kansas, New Mexico, Oklahoma, Texas↗

USGS1998

Surface-water quality at fixed sites in the Western Lake Michigan Drainages, Wisconsin and Michigan, and the effects of natural and human factors, 1993-95

Streamwater samples were collected from April 1993 through July 1995 at 11 fixed sites in the Western Lake Michigan Drainages Study Unit of the U.S. Geological Survey's National Water-Quality Assessment Program. Water samples were collected monthly at all Fixed Sites, and an additional two to four samples were collected each year during periods of high flow. Streamflow was monitored continuously at the Fixed Sites for the duration of the study period. This report describes field techniques used to collect the water samples, and the analytical methods used for laboratory analyses, statistical analyses of the data, and an attempt to determine the effect of natural and anthropogenic factors on concentrations of nutrients and selected major ions and suspended solids. Locations of eight of the Fixed Sites were selected to represent areas with unique combinations of land use/land cover, surficial deposits, and bedrock geology and are referred to as 'indicator sites.' The remaining three sites were located near the mouths of major rivers and are referred to as 'integrator sites.' The integrator sites represent a large part of the total flow from the Study Unit to Green Bay and western Lake Michigan, and drain various combinations of land use, bedrock, and surficial deposits. These data indicate that land use and surficial deposits may be the primary factors affecting nitrate and total phosphorus concentrations in this Study Unit. Median concentrations of nitrate at the forested sites were less than the National Median Concentration (NMC), and those at urban fixed sites were similar to the NMC. Median nitrate concentrations at the Tomorrow River, North Branch Milwaukee River, and Duck Creek agricultural indicator sites were twice the NMC, but median concentrations at the remaining agricultural indicator sites were similar to the NMC. Nitrate concentrations at one agricultural indicator site exceeded the U. S. Environmental Protection Agency (USEPA) maximum contaminant level in three run-off samples in the growing seasons of 1994 and 1995. Median concentrations of total phosphorus at the forested indicator sites were below the NMC. Tomorrow River was the only agricultural indicator site where the median total-phosphorus concentration was less than the NMC; median concentrations at the remaining agricultural Fixed Sites were similar to the NMC and exceeded 0.1 mg/L, the USEPA suggested total-phosphorus concentration in flowing water. The USEPA recommends that total-phosphorus concentration not exceed this limit to discourage excessive aquatic plant growth in flowing waters. Median total-phosphorus concentration at the urban indicator site was less than the urban NMC. Median concentrations for both nitrate and total phosphorus at the mouth of the Fox River and the Milwaukee River integrator sites were similar to the NMC for the dominant land use, agriculture, within their basins, and were lower than that at the Menominee River integrator site with a dominant forest land use. During this study, potassium concentrations were generally highest in areas of clay-dominated surficial deposits, silica was generally highest in areas of sandy surficial deposits, iron generally highest in areas of igneous/metamorphic bedrock, and calcium generally highest in areas of carbonate bedrock. The highest median fluoride concentration occurred at an urban site that receives treated water.

Michigan, Wisconsin↗

USGS2008

Anthropogenic organic compounds in source water of nine community water systems that withdraw from streams, 2002-05

Source water, herein defined as stream water collected at a water-system intake prior to water treatment, was sampled at nine community water systems, ranging in size from a system serving about 3,000 people to one that serves about 2 million people. As many as 17 source-water samples were collected at each site over about a 12-month period between 2002 and 2004 for analysis of 258 anthropogenic organic compounds. Most of these compounds are unregulated in drinking water, and the compounds analyzed include pesticides and selected pesticide degradates, gasoline hydrocarbons, personal-care and domestic-use compounds, and solvents. The laboratory analytical methods used in this study have relatively low detection levels - commonly 100 to 1,000 times lower than State and Federal standards and guidelines for protecting water quality. Detections, therefore, do not necessarily indicate a concern to human health but rather help to identify emerging issues and to track changes in occurrence and concentrations over time. About one-half (134) of the compounds were detected at least once in source-water samples. Forty-seven compounds were detected commonly (in 10 percent or more of the samples), and six compounds (chloroform, atrazine, simazine, metolachlor, deethylatrazine, and hexahydrohexamethylcyclopentabenzopyran (HHCB) were detected in more than one-half of the samples. Chloroform was the most commonly detected compound - in every sample (year round) at five sites. Findings for chloroform and the fragrances HHCB and acetyl hexamethyl tetrahydronaphthalene (AHTN) indicate an association between occurrence and the presence of large upstream wastewater discharges in the watersheds. The herbicides atrazine, simazine, and metolachlor also were among the most commonly detected compounds. Degradates of these herbicides, as well as those of a few other commonly occurring herbicides, generally were detected at concentrations similar to or greater than concentrations of the parent compound. Samples typically contained mixtures of two or more compounds. The total number of compounds and their total concentration in samples generally increased with the amount of urban and agricultural land use in a watershed. Annual mean concentrations of all compounds were less than human-health benchmarks. Single-sample concentrations of anthropogenic organic compounds in source water generally were less than 0.1 microgram per liter and less than established human-health benchmarks. Human-health benchmarks used for comparison were U.S. Environmental Protection Agency (USEPA) Maximum Contaminant Levels (MCLs) for regulated compounds and U.S. Geological Survey Health-Based Screening Levels for unregulated compounds. About one-half of all detected compounds do not have human-health benchmarks or adequate toxicity information for evaluating results in a human-health context. During a second sampling phase (2004-05), source water and finished water (water that has passed through all the treatment processes but prior to distribution) were sampled at eight of the nine community water systems. Water-treatment processes differ among the systems. Specifically, treatment at five of the systems is conventional, typically including steps of coagulation, flocculation, sedimentation, filtration, and disinfection. One water system uses slow sand filtration and disinfection, a second system uses ozone as a preliminary treatment step to conventional treatment, and a third system is a direct filtration treatment plant that uses many of the steps employed in conventional treatment. Most of these treatment steps are not designed specifically to remove the compounds monitored in this study. About two-thirds of the compounds detected commonly in source water were detected at similar frequencies in finished water. Although the water-treatment steps differ somewhat among the eight water systems, the amount of change in concentration of the compounds from source- to finish

Scientific Investigations Report↗

USGS2001

Occurrence and distribution of methyl tert-butyl ether and other volatile organic compounds in drinking water in the Northeast and Mid-Atlantic regions of the United States, 1993-98

Data on volatile organic compounds (VOCs) in drinking water supplied by 2,110 randomly selected community water systems (CWSs) in 12 Northeast and Mid-Atlantic States indicate 64 VOC analytes were detected at least once during 1993-98. Selection of the 2,110 CWSs inventoried for this study targeted 20 percent of the 10,479 active CWSs in the region and represented a random subset of the total distribution by State, source of water, and size of system. The data include 21,635 analyses of drinking water collected for compliance monitoring under the Safe Drinking Water Act; the data mostly represent finished drinking water collected at the pointof- entry to, or at more distal locations within, each CWS?s distribution system following any watertreatment processes. VOC detections were more common in drinking water supplied by large systems (serving more than 3,300 people) that tap surface-water sources or both surface- and groundwater sources than in small systems supplied exclusively by ground-water sources. Trihalomethane (THM) compounds, which are potentially formed during the process of disinfecting drinking water with chlorine, were detected in 45 percent of the randomly selected CWSs. Chloroform was the most frequently detected THM, reported in 39 percent of the CWSs. The gasoline additive methyl tert-butyl ether (MTBE) was the most frequently detected VOC in drinking water after the THMs. MTBE was detected in 8.9 percent of the 1,194 randomly selected CWSs that analyzed samples for MTBE at any reporting level, and it was detected in 7.8 percent of the 1,074 CWSs that provided MTBE data at the 1.0-?g/L (microgram per liter) reporting level. As with other VOCs reported in drinking water, most MTBE concentrations were less than 5.0 ?g/L, and less than 1 percent of CWSs reported MTBE concentrations at or above the 20.0-?g/L lower limit recommended by the U.S. Environmental Protection Agency?s Drinking-Water Advisory. The frequency of MTBE detections in drinking water is significantly related to high- MTBE-use patterns. Detections are five times more likely in areas where MTBE is or has been used in gasoline at greater than 5 percent by volume as part of the oxygenated or reformulated (OXY/RFG) fuels program. Detection frequencies of the individual gasoline compounds (benzene, toluene, ethylbenzene, and xylenes (BTEX)) were mostly less than 3 percent of the randomly selected CWSs, but collectively, BTEX compounds were detected in 8.4 percent of CWSs. BTEX concentrations also were low and just three drinkingwater samples contained BTEX at concentrations exceeding 20 ?g/L. Co-occurrence of MTBE and BTEX was rare, and only 0.8 percent of CWSs reported simultaneous detections of MTBE and BTEX compounds. Low concentrations and cooccurrence of MTBE and BTEX indicate most gasoline contaminants in drinking water probably represent nonpoint sources. Solvents were frequently detected in drinking water in the 12-State area. One or more of 27 individual solvent VOCs were detected at any reporting level in 3,080 drinking-water samples from 304 randomly selected CWSs (14 percent) and in 206 CWSs (9.8 percent) at concentrations at or above 1.0 ?g/L. High co-occurrence among solvents probably reflects common sources and the presence of transformation by-products. Other VOCs were relatively rarely detected in drinking water in the 12-State area. Six percent (127) of the 2,110 randomly selected CWSs reported concentrations of 16 VOCs at or above drinking-water criteria. The 127 CWSs collectively serve 2.6 million people. The occurrence of VOCs in drinking water was significantly associated (p<0.0001) with high population- density urban areas. New Jersey, Massachusetts, and Rhode Island, States with substantial urbanization and high population density, had the highest frequency of VOC detections among the 12 States. More than two-thirds of the randomly selected CWSs in New Jersey reported detecting VOC concentrations in drinking water at or above 1

Water-Resources Investigations Report↗

USGS1998

Evaluation of chemical data from selected sites in the Surface-Water Ambient Monitoring Program (SWAMP) in Florida

A cooperative study between the Florida Department of Environmental Protection (FDEP) and the U.S. Geological Survey was conducted to assess the integrity of selected water-quality data collected at 150 sites in the FDEP Surface-Water Ambient Monitoring Program (SWAMP) in Florida. The assessment included determining the consistency of the water-quality data collected statewide, including commonality of monitoring procedures and analytes, screening of the gross validity of a chemical analysis, and quality assurance and quality control (QA/QC) procedures. Four tests were used to screen data at selected SWAMP sites to estimate the gross validity of selected chemical data: (1) the ratio of dissolved solids (in milligrams per liter) to specific conductance (in microsiemens per centimeter); (2) the ratio of total cations (in milliequivalents per liter) multiplied by 100 to specific conductance (in microsiemens per centimeter); (3) the ratio of total anions (in milliequivalents per liter) multiplied by 100 to specific conductance (in microsiemens per centimeter); and (4) the ionic charge-balance error. Although the results of the four screening tests indicate that the chemical data generally are quite reliable, the extremely small number of samples (less than 5 percent of the total number of samples) with sufficient chemical information to run the tests may not provide a representative indication of the analytical accuracy of all laboratories in the program. In addition to the four screening tests, unusually low or high values were flagged for field and laboratory pH (less than 4.0 and greater than 9.0) and specific conductance (less than 10 and greater than 10,000 microsiemens per centimeter). The numbers of flagged data were less than 1 percent of the 19,937 water samples with pH values and less than 0.6 percent of the 16,553 water samples with specific conductance values. Thirty-four agencies responded to a detailed questionnaire that was sent to more than 60 agencies involved in the collection and analysis of surface-water-quality data for SWAMP. The purpose of the survey was to evaluate quality assurance methods and consistency of methods statewide. Information was compiled and summarized on monitoring network design, data review and upload procedures, laboratory and field sampling methods, and data practices. Currently, most agencies that responded to the survey follow FDEP-approved QA/QC protocol for sampling and have quality assurance practices for recording and reporting data. Also, most agencies responded that calibration procedures were followed in the laboratory for analysis of data, but no responses were given about the specific procedures. Approximately 50 percent of the respondents indicated that laboratory analysis methods have changed over time. With so many laboratories involved in analyzing samples for SWAMP, it is difficult to compare water quality from one site to another due to different reporting conventions for chemical constituents and different analytical methods over time. Most agencies responded that calibration methods are followed in the field, but no specific details were provided. Grab samples are the most common method of collection. Other data screening procedures are necessary to further evaluate the validity of chemical data collected at SWAMP sites. High variability in the concentration of targeted constituents may signal analytical problems, but more likely changes in concentration are related to hydrologic conditions. This underscores the need for accurate measurements of discharge, lake stage, tidal stage at the time of sampling so that changes in constituent concentrations can be properly evaluated and fluxes (loads) of nutrients or metals, for example, can be calculated and compared over time.

Florida↗

USGS1996

Geohydrology and water quality of stratified-drift aquifers in the middle Connecticut River basin, west-central New Hampshire

A study was done by the U.S. Geological Survey, in cooperation with the New Hampshire Department of Environmental Services, Water Resources Division, to describe the geohydrology and water quality of stratified-drift aquifers in the Middle Connecticut River Basin, west-central New Hampshire Stratified-drift aquifers discontinuously underlie 123 mi2 (square miles) of the Middle Connecticut River Basin, which has a total drainage area of 987 mi 2. Saturated thicknesses of stratified drift in the study area are locally greater than 500 feet but generally are less than 100 feet. Aquifer transmissivity locally exceeds 4,000 ft2/d (feet squared per day) but is generally less than 1,000 ft2/d. In only 17.2 mi2 of the study area are the aquifers identified as having a transmissivity greater than 1,000 ft2/d. As of 1990, total groundwater withdrawals from stratified drift for municipal supply were about 1.5 Mgal/d (million gallons per day) in the study area. Many of the stratified-drift aquifers underlying the study area are not developed to their fullest potential. The geohydrologic investigation of the stratified-drift aquifers focused on aquifer properties, including aquifer boundaries; recharge, discharge, and direction of ground-water flow; saturated thickness and storage; and transmissivity. Surficial-geologic mapping assisted in the determination of aquifer boundaries. Data from more than 1,000 wells, test borings, and springs were used to prepare maps of water-table altitude, saturated thickness, and transmissivity of stratified drift. More than 11 miles of seismic-refraction profiling at 95 sites was used in the preparation of the water-table-altitude and saturated-thickness maps. Seismic-reflection data collected along 1.6 miles of Mascoma Lake also were used in preparation of the saturated-thickness maps. Four stratified-drift aquifers in the towns of Franconia, Haverhill, and Lisbon were analyzed to estimate the water availability on the basis of analytical ground-water model simulation based on the Theis confined-flow equation adjusted to account for boundary effects commonly associated with stratified-drift aquifers. Conservative estimates of water availability during a 180-day period of no recharge were estimated to be 1.9 Mgal/d for the Meadow Brook aquifer; 1.8 Mgal/d for the Ham Branch Brook aquifer; 1.5 Mgal/d for the Salmon Hole aquifer; and 1.4 Mgal/d for the Haverhill-French Pond aquifer. Water-availability estimates would be higher if periods of recharge were accounted for and if less conservative boundary conditions were used in the model. Results of analysis of water samples from 26 observation wells, 3 municipal water-supply wells, and 1 public-supply spring show that, with the exception of dissolved iron and manganese in some samples, water in the stratified-drift aquifers generally meets the U.S. Environmental Protection Agency's primary and secondary drinking-water standards.

New Hampshire↗

USGS2010

Occurrence and distribution of organic chemicals and nutrients and comparison of water-quality data from public drinking-water supplies in the Columbia aquifer in Delaware, 2000-08

The U.S. Geological Survey, in cooperation with the Delaware Department of Natural Resources and Environmental Control and the Delaware Geological Survey, conducted a groundwater-quality investigation to (a) describe the occurrence and distribution of selected contaminants, and (b) document any changes in groundwater quality in the Columbia aquifer public water-supply wells in the Coastal Plain in Delaware between 2000 and 2008. Thirty public water-supply wells located throughout the Columbia aquifer of the Delaware Coastal Plain were sampled from August through November of 2008. Twenty-two of the wells in the sampling network for this project were previously sampled in 2000. Eight new wells were selected to replace wells no longer in use. Groundwater collected from the wells was analyzed for the occurrence and distribution of selected pesticides, pesticide degradates, volatile organic compounds, nutrients, and major inorganic ions. Nine of the wells were analyzed for radioactive elements (radium-226, radium-228, and radon). Groundwater-quality data were compared for sites sampled in both 2000 and 2008 to document any changes in water quality. One or more pesticides were detected in samples from 29 of the 30 wells. There were no significant differences in pesticide and pesticide degradate concentrations and similar compounds were detected when comparing sampling results from 2000 and 2008. Pesticide and pesticide degradate concentrations were generally less than 1 microgram per liter. Twenty-four compounds, 14 pesticides, and 10 pesticide degradates were detected in at least one sample; the pesticide degradates, metolachlor ethanesulfonic acid, deethylatrazine, and alachlor ethanesulfonic acid were the most frequently detected compounds, each found in more than 50 percent of samples. Almost 80 percent of the detected pesticides were agricultural herbicides, which reflects the prevalence and wide distribution of agriculture in sampled areas, as well the dominance of agricultural pesticides among the target analytes for this study. No concentration of a pesticide or pesticide degradate exceeded any regulatory standard. Dieldrin, an insecticide that has been banned for several decades, was detected at a concentration that exceeded a non-regulatory health-based screening level of 0.002 micrograms per liter at nine sites. Volatile organic compounds (VOCs) were generally detected at concentrations of less than 1 microgram per liter, although 7 of the 31 detected VOCs had concentrations greater than 1 microgram per liter. There were no significant differences in VOC concentrations from 2000 to 2008; however, among the resampled wells, the mean number of VOCs detected per well was significantly different over the 8-year period. The number of VOCs detected per well decreased in 73 percent of the resampled wells; the decrease ranged from one to eight fewer detections in 2008 than in 2000. Chloroform and methyl tert-butyl ether were the most frequently detected VOCs, at 90 percent and 63 percent, respectively, among the 30 wells. Solvents were the most frequently detected class of VOCs. All measured concentrations of VOCs in groundwater were below established standards for drinking water and below other health-based guidelines. There were no significant differences in nutrient or major-ion concentrations between 2000 and 2008, however, the medians of two field measurements, pH and dissolved oxygen, were significantly higher in 2008 than in 2000 in the resampled wells. Although pH and dissolved oxygen were higher, water was still acidic and predominantly oxic. Nitrate was the predominant nutrient species in the Columbia aquifer, with a 90-percent detection frequency. The median nitrate concentration in groundwater was 4.88 milligrams per liter, which was slightly lower than, but not significantly different from, the median of 5.23 milligrams per liter for the 2000 samples. Concentrations of nitrate exceeded the U.S. Environmental Protection Agency's Maximum Contaminant Level or Federal drinking-water standard of 10 milligrams per liter as nitrogen in samples from two wells. Eight of the 30 wells sampled had iron or manganese concentrations that exceeded the U.S. Environmental Protection Agency's Secondary Maximum Contaminant Level; nine samples exceeded the Health Advisory Limit set by the Delaware Division of Public Health of 20 milligrams per liter for sodium in drinking water. Two radiochemical isotopes, radium-226 and radon-222, were detected in all nine groundwater samples analyzed; five samples had detectable levels of radium-228 activity. None of the samples exceeded the U.S Environmental Protection Agency's Maximum Contaminant Level for radium or radon in drinking water. Although radioactive elements were more frequently detected in 2008 than in 2000, this increased detection frequency is more likely due to lower detection levels in 2008 than 2000. The average age of groundwater entering the screens of the production wells sampled in 2008 ranged from 6 to 35 years, with a median groundwater age of 22 years. Groundwater age was positively correlated with well depth and negatively correlated with dissolved oxygen. Data from the 22 resampled wells indicate a significant positive difference in the average modeled groundwater-sample-age results. The average groundwater age from samples collected in 2008 was generally 7 years older than the average groundwater age from samples collected in 2000.

Delaware↗

USGS2002

Ground-water quality in the West Salt River Valley, Arizona, 1996–98 — Relations to hydrogeology, water use, and land use

The U.S. Geological Survey collected and analyzed ground-water samples in the West Salt River Valley from 64 existing wells selected by a stratified-random procedure. Samples from an areally distributed group of 35 of these wells were used to characterize overall ground-water quality in the basin-fill aquifer. Analytes included the principal inorganic constituents, trace constituents, pesticides, and volatile organic compounds. Additional analytes were tritium, radon, and stable isotopes of hydrogen and oxygen. Analyses of replicate samples and blank samples provided evidence that the analyses of the ground-water samples were adequate for interpretation. The median concentration of dissolved solids in samples from the 35 wells was 560 milligrams per liter, which exceeded the U.S. Environmental Protection Agency Secondary Maximum Contaminant Level for drinking water. Eleven of the 35 samples had a nitrate concentration (as nitrogen) that exceeded the U.S. Environmental Protection Agency Maximum Contaminant Level for drinking water of 10 milligrams per liter. Pesticides were detected in eight samples; concentrations were below the Maximum Contaminant Levels. Deethylatrazine was most commonly detected. The pesticides were detected in samples from wells in agricultural or urban areas that have been irrigated. Concentrations of all trace constituents, except arsenic, were less than the Maximum Contaminant Levels. The concentration of arsenic exceeded the Maximum Contaminant Level of 50 micrograms per liter in two samples. Nine monitoring wells were constructed in an area near Buckeye to assess the effects of agricultural land use on shallow ground water. The median concentration of dissolved solids was 3,340 milligrams per liter in samples collected from these wells in August 1997. The nitrate concentration (as nitrogen) exceeded the Maximum Contaminant Level (10 milligrams per liter) in samples from eight of the nine monitoring wells in August 1997 and again in February 1998. Analyses of all samples collected from the monitoring wells indicated low concentrations of pesticides and volatile organic compounds. The most frequently detected pesticides were deethylatrazine and atrazine. Trichloromethane (chloroform) and tetrachloroethene (PCE) were the most frequently detected volatile organic compounds in the monitoring wells. Two compounds [dieldrin and 1,1-dichloro-2,2-bis(p-dichlorodiphenyl)ethylene (DDE)], decomposition products of two banned pesticides, aldrin and dichlorodiphenylethylene (DDT), were detected at low concentrations in samples analyzed for the agricultural land-use study. In the West Salt River Valley, a high concentration of the heavier oxygen isotope?oxygen-18?in ground water generally indicates effects of evaporation on recharge water from irrigation. Wells in undeveloped areas and wells that have openings beneath a confining bed generally yield ground water that is free of the effects of irrigation seepage. Samples from these wells did not contain detectable concentrations of pesticides. The median concentrations of nitrate (as nitrogen) and dissolved solids in samples from wells in undeveloped areas were 1.7 milligrams per liter and 257 milligrams per liter, respectively. The median concentrations of nitrate (as nitrogen) and dissolved solids in samples from wells that yield water from below confining beds were 2.0 and 747 milligrams per liter, respectively.

Arizona↗

USGS2000

A Synopsis of Technical Issues for Monitoring Sediment in Highway and Urban Runoff

Accurate and representative sediment data are critical for assessing the potential effects of highway and urban runoff on receiving waters. The U.S. Environmental Protection Agency identified sediment as the most widespread pollutant in the Nation's rivers and streams, affecting aquatic habitat, drinking water treatment processes, and recreational uses of rivers, lakes, and estuaries. Representative sediment data are also necessary for quantifying and interpreting concentrations, loads, and effects of trace elements and organic constituents associated with highway and urban runoff. Many technical issues associated with the collecting, processing, and analyzing of samples must be addressed to produce valid (useful for intended purposes), current, complete, and technically defensible data for local, regional, and national information needs. All aspects of sediment data-collection programs need to be evaluated, and adequate quality-control data must be collected and documented so that the comparability and representativeness of data obtained for highway- and urban-runoff studies may be assessed. Collection of representative samples for the measurement of sediment in highway and urban runoff involves a number of interrelated issues. Temporal and spatial variability in runoff result from a combination of factors, including volume and intensity of precipitation, rate of snowmelt, and features of the drainage basin such as area, slope, infiltration capacity, channel roughness, and storage characteristics. In small drainage basins such as those found in many highway and urban settings, automatic samplers are often the most suitable method for collecting samples of runoff for a variety of reasons. Indirect sediment-measurement methods are also useful as supplementary and(or) surrogate means for monitoring sediment in runoff. All of these methods have limitations in addition to benefits, which must be identified and quantified to produce representative data. Methods for processing raw sediment samples (including homogenization and subsampling) for subsequent analysis for total suspended solids or suspended-sediment concentration often increase variance and may introduce bias. Processing artifacts can be substantial if the methods used are not appropriate for the concentrations and particle-size distributions present in the samples collected. Analytical methods for determining sediment concentrations include the suspended-sediment concentration and the total suspended solids methods. Although the terms suspended-sediment concentration and total suspended solids are often used interchangeably to describe the total concentration of suspended solid-phase material, the analytical methods differ and can produce substantially different results. The total suspended solids method, which commonly is used to produce highway- and urban-runoff sediment data, may not be valid for studies of runoff water quality. Studies of fluvial and highway-runoff sediment data indicate that analyses of samples by the total suspended solids method tends to under represent the true sediment concentration, and that relations between total suspended solids and suspended-sediment concentration are not transferable from site to site even when grain-size distribution information is available. Total suspended solids data used to calculate suspended-sediment loads in highways and urban runoff may be fundamentally unreliable. Consequently, use of total suspended solids data may have adverse consequences for the assessment, design, and maintenance of sediment-removal best management practices. Therefore, it may be necessary to analyze water samples using the suspended-sediment concentration method. Data quality, comparability, and utility are important considerations in collection, processing, and analysis of sediment samples and interpretation of sediment data for highway- and urban-runoff studies. Results from sediment studies must be comparable and readily transf

Open-File Report↗

USGS2008

Occurrence of organic wastewater compounds in the Tinkers Creek watershed and two other tributaries to the Cuyahoga River, northeast Ohio

The U.S. Geological Survey - in cooperation with the Ohio Water Development Authority; National Park Service; Cities of Aurora, Bedford, Bedford Heights, Solon, and Twinsburg; and Portage and Summit Counties - and in collaboration with the Ohio Environmental Protection Agency, did a study to determine the occurrence and distribution of organic wastewater compounds (OWCs) in the Tinkers Creek watershed in northeastern Ohio. In the context of this report, OWCs refer to a wide range of compounds such as antibiotics, prescription and nonprescription pharmaceuticals, personal-care products, household and industrial compounds (for example, antimicrobials, fragrances, surfactants, fire retardants, and so forth) and a variety of other chemicals. Canisters containing polar organic integrative sampler (POCIS) and semipermeable membrane device (SPMD) media were deployed instream for a 28-day period in Mayand June 2006 at locations upstream and downstream from seven wastewater-treatment-plant (WWTP) outfalls in the Tinkers Creek watershed, at a site on Tinkers Creek downstream from all WWTP discharges, and at one reference site each in two nearby watersheds (Yellow Creek and Furnace Run) that drain to the Cuyahoga River. Streambed-sediment samples also were collected at each site when the canisters were retrieved. POCIS and SPMDs are referred to as 'passive samplers' because they sample compounds that they are exposed to without use of mechanical or moving parts. OWCs detected in POCIS and SPMD extracts are referred to in this report as 'detections in water' because both POCIS and SPMDs provided time-weighted measures of concentration in the stream over the exposure period. Streambed sediments also reflect exposure to OWCs in the stream over a long period of time and provide another OWC exposure pathway for aquatic organisms. Four separate laboratory methods were used to analyze for 32 antibiotic, 20 pharmaceutical, 57 to 66 wastewater, and 33 hydrophobic compounds. POCIS and streambed-sediment extracts were analyzed by both the pharmaceutical and wastewater methods. POCIS extracts also were analyzed by the antibiotic method, and SPMD extracts were analyzed by the hydrophobic-compound method. Analytes associated with a given laboratory method are referred to in aggregate by the method name (for example, antibiotic-method analytes are referred to as 'antibiotic compounds') even though some analytes associated with the method may not be strictly classified as such. In addition, some compounds were included in the analyte list for more than one laboratory method. For a given sample matrix, individual compounds detected by more than one analytical method are included independently in counts for each method. A total of 12 antibiotic, 20 pharmaceutical, 41 wastewater, and 22 hydrophobic compounds were detected in water at one or more sites. Eight pharmaceutical and 37 wastewater compounds were detected in streambed sediments. The numbers of detections at reference sites tended to be in the low range of detection counts observed in the Tinkers Creek watershed for a given analytical method. Also, the total numbers of compounds detected in water and sediment at the reference sites were less than the total numbers of compounds detected at sites in the Tinkers Creek watershed. With the exception of hydrophobic compounds, it was common at most sites to have more compounds detected in samples collected downstream from WWTP outfalls than in corresponding samples collected upstream from the outfalls. This was particularly true for antibiotic, pharmaceutical, and wastewater compounds in water. In contrast, it was common to have more hydrophobic compounds detected in samples collected upstream from WWTP outfalls than downstream. Caffeine, fluoranthene, N,N-diethyl-meta-toluamide (DEET), phenanthrene, and pyrene were detected in water at all sites in the Tinkers Creek watershed, irrespective of whether the site was upstream or downs

Ohio↗

USGS2022

Occurrence of per- and polyfluoroalkyl substances and inorganic analytes in groundwater and surface water used as sources for public water supply in West Virginia

Per- and polyfluoroalkyl substances (PFAS) are widely observed anthropogenic compounds found in water supplies worldwide and increasingly linked with adverse health effects in humans. In 2019, the West Virginia Legislature recognized the contamination risk to public source-water supplies posed by PFAS and passed a resolution that required a statewide PFAS study. The purpose of the resolution was to understand the occurrence and distribution of PFAS contamination throughout the State’s rivers, lakes, and groundwater aquifers. The U.S. Geological Survey has worked in cooperation with the West Virginia Department of Environmental Protection and West Virginia Department of Health and Human Resources to collect raw-water samples at 279 public-water systems across West Virginia. Public-water systems sampled for this study were identified by the West Virginia Department of Health and Human Resources and included all community water systems in the State and all daycares and schools that operate their own water systems. Raw source water was sampled for both groundwater and surface-water sites at the first available tap in the public-water system, prior to any treatment. One hundred and seventy-three samples were collected from groundwater sources and 106 samples were collected from surface-water sources. Parameters collected at the time of sampling included pH, specific conductance, water temperature, dissolved oxygen, turbidity, and alkalinity. PFAS was analyzed at all 279 sites, major ions and trace elements were analyzed at 272 sites, and nutrients were analyzed at 270 sites. The type of source water used for public supply in West Virginia is generally dependent on geology with more groundwater sites sampled in high-yield aquifers such as karst and alluvium. Surface-water sites were more evenly distributed throughout the State and are often the only source used in areas underlain by lower-yielding fractured-rock aquifers. Twenty-four percent of the sites sampled for this study had at least 1 PFAS detected, 47 of which were in groundwater sources and 20 in surface-water sources. Five sites exceeded the U.S. Environmental Protection Agency’s health advisory for combined perfluorooctanoate and perfluorooctanesulfonate concentrations of 70 nanograms per liter. These sites were located in highly susceptible karst and alluvial groundwater aquifers on the east and west sides of the State. Higher PFAS concentrations were more commonly found in groundwater than surface-water sources, and high concentrations and PFAS detections were generally concentrated in the Ohio River Valley and West Virginia’s eastern panhandle. PFAS was rarely detected in groundwater sites in fractured-rock aquifers and abandoned underground coal-mine aquifers in the Appalachian Plateaus Physiographic Province had very little PFAS detected. These data represent a baseline summary of source water in West Virginia. Additional studies may be needed to understand exposure to private homeowners with domestic-water sources, variability of PFAS concentrations over time, and PFAS in finished drinking water as evaluated by current and future drinking-water regulations.

West Virginia↗

USGS1995

Ground-water flow and water quality in the sand aquifer of Long Beach Peninsula, Washington

This report describes an investigation of ground-water flow and water quality in the sand aquifer of the Long Beach Peninsula. The peninsula is located in the southwestern corner of the State of Washington, is about 27 miles long, and has an average width of about 1.5 miles. It is surrounded by seawater, by the Pacific Ocean on the west and Willapa Bay on the east. Water supplies on the peninsula are derived mostly from a local water-table aquifer composed largely of sand. The recent growth of population on the peninsula and the projected future growth have created concerns about the quantity and quality of the ground-water resource. Some issues include declining ground-water levels from increased pumpage, and ground-water contamination from seawater intrusion, pesticides or fertilizers from cranberrygrowing areas, and septic-system effluent. The ground-water system of the Long Beach Peninsula consists of a sand aquifer with some lenses of silt and clay that may act as confining beds in local areas. Data are lacking or inconsistent to define a confining bed that extends throughout the peninsula. Hydraulic conductivity calculated from slug tests in 58 shallow wells ranged from 10 to 37 feet per day with a median of 22 feet per day. Average annual ground-water recharge by infiltration and percolation of precipitation is estimated to be about 58 inches or 111,000 acre-feet, which is 72 percent of the average annual precipitation of 80 inches. Average annual ground-water discharge is estimated to be about 30,200 acre-feet to the Pacific Ocean, 56,000 acre-feet to Willapa Bay, and 24,800 acre-feet to surface-water drainage channels. Ground-water movement is generally perpendicular to the spine of the peninsula. A ground-water divide occurs along a north-south line and ground water flows west or east from the divide toward the Pacific Ocean or Willapa Bay. There does not appear to have been any long-term decline of the water table of the sand aquifer from 1974-92. Ground-water levels measured at three east-west cross sections in 1974-75 were at about the same altitude as water levels measured in 1992. Relatively accurate individual regression relations were developed at 45 wells with ground-water altitude as a response variable and cumulative precipitation for 4 months as an explanatory variable. The average coefficient of determination for all individual relations was 0.77, with a range of 0.11 to 0.89. Some empirical frequency or probability relations for precipitation and ground-water levels were used to estimate how often the maximum water levels measured in this study would be expected to occur in the future. These water levels reflected the lower-than-average precipitation that occurred during the study. Assuming that the annual maximum precipitation for 4 consecutive months is random and independent, the historical record of precipitation is representative of the future distribution of precipitation, and the relation between precipitation and water levels is accurate and stationary; a probability analysis of the historical record indicates that in any one year in the future there is a probability of 70 percent that the maximum water levels measured in wells during the winter of 1991-92 would be equaled or exceeded. The shallow ground water had generally low dissolved-solids concentrations in July 1992, with a median concentration of 92 milligrams per liter (mg/L) and a range of 56 to 218 mg/L. Sodium was the dominant cation and bicarbonate was the dominant anion. The distribution of hardness of the water samples was 84 percent with soft water and 16 percent with moderately hard water. The water quality of the shallow ground water was generally good, with a few small to moderate problems. A natural problem is locally high concentrations of dissolved iron. About 30 percent of the water samples had dissolved-iron concentrations of greater than 0.3 mg/L, which is the secondary maximum contaminant level established by the U.S. Environmental Protection Agency. No appreciable amount of seawater has intruded into the sand aquifer. The samples of shallow ground water collected in July 1992 had a median chloride concentration of 15 mg/L and a maximum concentration of 52 mg/L. The heavy average annual precipitation of about 80 inches, large average annual ground-water recharge of about 58 inches or 111,000 acre-feet, and small ground-water withdrawal rate (about 780 acre-feet per year in 1992) combine to maintain a thick freshwater lens of ground water that prevents seawater intrusion throughout the year. Agricultural activities do not appear to have appreciably affected the quality of shallow ground water on the Long Beach Peninsula. The concentration of nitrate in ground water was not significantly higher near cranberry-growing areas, and no sample of ground water or surface water had concentrations of selected pesticides or associated compounds that were above the analytical detection limits. Of the seven ground-water samples in which bacteria were detected, only one sample appeared to be related to agriculture; that sample was from a well located in an area where cattle graze for part of the year. Septic systems probably caused an increase in the concentration of nitrate in shallow ground water in areas of higher population density. Concentrations of nitrate were significantly related to population density. However, the concentrations were not generally high; median concentrations of nitrate increased from less than 0.05 mg/L in areas of low population density to 0.74 mg/L in areas of high density. Septic systems did not cause regional bacterial contamination of the ground water. Bacteria were detected in seven ground-water samples; however, only two of those samples were from wells that are close to septic systems. A limited amount of historical water-quality data is available for the peninsula; therefore, it is difficult to assess long-term changes. From 1968-92, chloride concentrations and values of specific conductance appear to have remained stable. Likewise, it appears that nitrate concentrations did not change from 1987-92.

Washington↗

USGS2019

Assessment of the presence of sewage in the Mill River under low-flow conditions, Springfield, Massachusetts, 2010–11

The U.S. Geological Survey, in cooperation with the Pioneer Valley Planning Commission, the U.S. Environmental Protection Agency, and the Massachusetts Department of Environmental Protection Senator William X. Wall Experiment Station, assessed the presence of 14 commonly used human-health pharmaceutical compounds, fecal indicator bacteria, and other man-made compounds indicative of the presence of human sewage in the lower reach of the Mill River near its confluence with the Connecticut River in Springfield, Massachusetts. The study was part of the Tri-State Connecticut River Targeted Watershed Initiative and involved the collection and analysis of raw river water at three sites along the reach, extending from Watershops Pond to the mouth, over the course of a low-flow period, July through November 2010. Previous studies in the region indicated that nonpoint or undocumented sources of wastewater contributed a variety of organic contaminants and potentially harmful bacteria to rivers under both high- and low-flow conditions. Additional samples, including a raw sewage sample collected near a Mill River combined sewer overflow during a non-overflow period, were collected in March 2011. The study was designed to determine if city sewage or other domestic sources of wastewater were entering the river within this reach during low-flow conditions. No definitive evidence of sewage was measured in Mill River water samples collected during the study period. Fecal indicator bacteria, including Escherichia coli ( E. coli ) and enterococci bacteria, were detected in all Mill River water samples. In the DNA analysis of enterococci cultures from the Mill River, samples generally tested negative for the Enterococcus faecium ( esp ) human-specific genetic marker, whereas the raw sewage sample tested positive. Samples also generally tested negative in the human-specific rDNA marker assay for the anaerobic bacterium Bacteroidetes . Samples tested negative in 2010 for two Bacteroidetes human-specific genetic markers, HF134 and HF183, except samples from near the mouth of the Mill River, which tested positive. Samples collected in March 2011 from all three measurement sites tested positive for both markers. The results of bacterial analyses suggest that the fecal bacteria in summer and fall months are most likely of animal origin rather than human. Despite the urban setting, long history of development, and many potential sources of man-made contamination in the Mill River, none of the 12 water samples collected during the study contained targeted pharmaceutical compounds at concentrations greater than the analytical reporting levels. Other man-made compounds, like fluorescent whitening agents, were measured and detected in samples at low concentrations 4 out of 5 times the samples were collected; however, the other lines of evidence do not support a sewer source but rather other nonpoint sources upstream in the watershed. The results of this study do not support the hypothesis that aging sewer lines or combined sewer overflow infrastructure leak into the Mill River as tested during the low-flow conditions during sampling for this study. None of the results from Mill River samples offer conclusive evidence of the presence of sewage. Some low-level detections of pharmaceutical compounds, other man-made chemicals, and bacteria suggest an upstream, nonpoint source. A single raw sewage sample was collected, diluted, and examined for comparison with Mill River water samples and to ensure that the analytical methods could detect typical wastewater constituents. High levels of bacteria were measured, and low levels of three anthropogenic pharmaceutical compounds were detected, confirming the effectiveness of the sub-part-per-million method. The concentration of fluorescent whitening agent-1 in the sewage sample was 90,000 times greater than the median concentration in the Mill River samples.

Massachusetts↗

USGS2013

Characterization and data-gap analysis of surface-water quality data in the Piceance study area, western Colorado, 1959–2009

The U.S. Geological Survey, in cooperation with Federal, State, county, and industry partners, developed a Web-accessible common data repository to provide access to historical and current (as of August 2009) water-quality information (available on the Internet at http://rmgsc.cr.usgs.gov/cwqdr/Piceance/index.shtml ). Surface-water-quality data from public and private sources were compiled for the period 1931 to 2009 and loaded into the common data repository for the Piceance Basin. A subset of surface-water-quality data for 1959 to 2009 from the repository were compiled, reviewed, and checked for quality assurance for this report. This report contains data summaries, comparisons to water-quality standards, trend analyses, a generalized spatial analysis, and a data-gap analysis for select water-quality properties and constituents. Summary statistics and a comparison to standards were provided for 347 sites for 33 constituents including field properties, nutrients, major ions, trace elements, suspended sediment, Escherichia coli, and BTEX (benzene, toluene, ethylbenzene, and xylene). When sufficient data were available, trends over time were analyzed and loads were calculated for those sites where there were also continuous streamflow data. The majority of sites had information on field properties. Water temperature data was available for 316 sites where data were collected between 1959 and 2009. The only trend that was detected in temperature was an upward trend at the Gunnison River near Grand Junction, Colorado. There were 326 values out of a total of 32,006 values in the study area that exceeded the aquatic-life standard for daily maximum water temperature. For the entire study area, 196 sites had dissolved-oxygen data collected between 1970 and 2009, and median dissolved-oxygen concentrations ranged from 6.8 to11.2 milligrams per liter (mg/L). There were 185 concentrations that exceeded the dissolved oxygen aquatic-life standard out of a total of 11,248 values. The pH data were available for 276 sites, and median pH values ranged from 7.5 to 9.0. There were 241 values that exceeded the high pH standard and 13 values that were less than the low pH standard of the 16,790 values in the study area. Nutrients within the study area were not well represented in each basin and were often not being sampled currently. For the entire study area, 62 sites had nitrate data collected between 1958 and 2009, and median nitrate concentrations ranged from less than detection to 3.72 mg/L as nitrogen. The maximum contaminant level for domestic water supply for nitrate is 10 mg/L and was exceeded once in 3,736 samples. Total phosphorus was collected at 113 sites between 1974 and 2009, and median total phosphorus concentrations ranged from less than detection to 5.04 mg/L. The U.S. Environmental Protection Agency recommendation for phosphorus is less than 0.1 mg/L, and 1,469 of 4,842 samples exceeded this recommended standard. An upward trend in both nitrate and total phosphorus was detected in the White River above Coal Creek near Meeker, Colo. Standards for major ions exist only for chloride and sulfate. For the entire study area, 118 sites had both chloride and sulfate concentration data collected between 1958 and 2009. Median chloride concentrations ranged from 0.085 mg/L to 280 mg/L. Median sulfate concentrations ranged from 4.57 mg/L to 15,000 mg/L. Both chloride and sulfate domestic water-supply standards are 250 mg/L. There were 120 chloride concentrations and 1,111 sulfate concentration samples that exceeded these standards. A downward trend in dissolved solids was detected at the Colorado River near the Colorado-Utah state border and could be a result of salinity control work near Grand Junction, Colo. Trace elements were relatively well represented both temporally and spatially in the study area though the number of trace element samples per site was not typically enough to compute trends or loads except for selenium. There were 127 sites that had dissolved iron concentration data collected between 1961 and 2009, and median iron concentrations ranged from less than detection to 1,100 micrograms per liter (µg/L). The 30-day drinking-water standard for iron is 300 µg/L, and 203 samples exceeded the standard. Selenium was the best represented trace element with selenium concentration data collected at 197 sites between 1973 and 2009, and median selenium concentrations range from less than detection to 181 µg/L. The chronic standard of 4.6 µg/L for selenium concentrations was exceeded in 899 samples, and the acute aquatic-life standard of 18.4 µg/ for selenium was exceeded in 629 samples. High concentrations of selenium are of concern in the Lower Gunnison River Basin because of the combination of geologic formations and land use. There were significant downward trends in selenium at both main-stem sites on the Gunnison River at Delta, Colo., and the Gunnison River near Grand Junction, Colo. High selenium concentrations correlate with high salinity concentrations; thus, when salinity control efforts are conducted in selenium-rich areas in the Lower Gunnison River Basin, both salinity and selenium have the potential to decrease. Spatial, temporal, and analytical data gaps were identified in the study area. The spatial coverage of sampling sites could be expanded in the White River Basin by adding more tributary sites. No water-quality data exist for tributary streams in the area north of Rangely, Colo., where extensive energy development has occurred in a complex geologic setting. Douglas Creek has a drainage area of 425 square miles and has limited historic water-quality and water-quantity data. Limited data were available for field properties, major ions, nutrients, and trace elements on the main stem of the Colorado River between Glenwood Springs and Cameo, Colo. Nutrient data were minimally collected upstream from Colorado River at the Colorado-Utah state border and on the Gunnison River (major tributary in the reach). Approximately 30 percent of the samples for total phosphorus in the Lower Gunnison River Basin exceeded the recommended standard, yet there were insufficient data to do trends analysis in the Lower Gunnison River Basin except at the Gunnison near Grand Junction site. There is limited trace element data except for selenium in the Lower Gunnison River Basin. Additional sampling is necessary to understand the occurrence, concentrations, and loads of these constituents.

Colorado↗

USGS2021

Cape Romain partnership for coastal protection

This final report summarizes activities, outcomes, and lessons learned from a 3-year project titled “Climate Change Adaptation for Coastal National Wildlife Refuges” with the Cape Romain National Wildlife Refuge (NWR) and local partners in the surrounding South Carolina Lowcountry. The Lowcountry is classified as the 10-county area encompassing the coastal plain of South Carolina (this report specifically focuses on Berkeley, Charleston, and Georgetown Counties). The goals of this work, sponsored by the U.S. Geological Survey’s Southeast Climate Adaptation Science Center (SECASC), were to foster active engagement with stakeholders; to develop a comprehensive definition of adaptation problems faced by agencies, organizations, and individuals near the Cape Romain NWR that accounts for global change, local values, knowledge and perceptions; and to encourage social learning and building of effective networks and trust across South Carolina Lowcountry organizations and individuals. Although project scoping began at the scale of the Atlantic seaboard, by engaging with NWRs from Massachusetts to Florida, participating refuge personnel eventually selected the Cape Romain NWR to serve as a case study for testing our goals. The Cape Romain Partnership for Coastal Conservation was established to address global change impacts at a regional level and includes representation from Federal and State resource agencies, local conservation nongovernmental organizations, and organizations representing underserved community interests. Research topics, originating from discussions with Cape Romain Partnership for Coastal Conservation members, focused on quantifying key drivers of change including localized sea-level rise (SLR) predictions, estimates of coastal hurricane inundation as amplified by SLR, and urban growth trends and forecasts. These key drivers provided a foundation to engage stakeholders in planning exercises to begin a process of collective understanding and collaborative decision making. The goal of this process was to develop collective strategies of adaptation to enhance community and ecosystem resilience in the South Carolina Lowcountry. South Carolina’s Lowcountry is experiencing rapid environmental and social transformation because of SLR rates approaching twice the global average, chronic tidal flooding and catastrophic storm surges, erosion and loss of habitats that provide essential services to wildlife and humans, and increasing social polarization fueled by aggressive low-density urban growth and other forms of land conversion. To support characterizations of plausible future scenarios, we used available or, in some cases, developed new models to project future conditions of key environmental and social-economic drivers. Because of the imprecision of mean global SLR projections, the SECASC commissioned a climatological study to account for local conditions and multiple representative concentration pathways to project a tailored distribution of future sea levels. These projections were matched to SLR scenarios provided by existing models to anticipate the range of future coastal habitat changes in the South Carolina Lowcountry. SLR scenarios were also incorporated into existing storm-surge models, which do not account for alternate baseline sea levels, to project the local effects of future hurricanes. To evaluate the extent and effects of population growth and urban expansion, we relied on an existing urban-growth model to map the spatial distribution of land-conversion probabilities, the total area of which is predicted to increase twofold to threefold over the next 60 years. In addition to this simplified model, an econometric model is in development to account for nonlinear feedback dynamics in land value, land use, and ecosystem service production. Although not yet completed, the goals of this model are to produce more-detailed projections of growth dynamics and to allow predictions of development patterns resulting from alternate land-use planning policies and incentives. Collaborative planning for an uncertain future requires more than providing decision makers with information on future physical and ecological conditions; developing effective and consensual strategies must also integrate sociological values, multiple cultural perspectives, and an understanding of human behavior. To support broad stakeholder engagement in integrative approaches to adaptation planning, emphasis was placed on the importance of considering differences in how individuals perceive their environment and create meaning. Because cultural frameworks form the basis for perceptions and, ultimately, the behaviors of individuals and institutions, we describe a model of human behavior and how it can be used to understand the effect of cultural complexity and variation in perception on choices, behavioral change, and long-term maintenance of behaviors. We consider a model commonly used in the field of behavioral health that accommodates variation in human perception when describing stages of behavior and the dynamics of behavioral change. Tailoring communication and engagement activities to targeted stakeholders is likely to benefit from increased understanding of behavioral change processes. The complex nature of this problem limited the usefulness of a traditional decision-analytic approach, we explored alternative methods for engagement, collaborative learning and decision making. Recognizing that project partners and Lowcountry stakeholders may be at different stages of preparedness and interest level for modifying behavior as a function of global change, we facilitated a scenario-planning exercise to familiarize partners with this well-established approach for communicating the opportunities and threats arising under alternative, plausible futures. We developed narratives for four alternative South Carolina Lowcountry scenarios to be used in later strategic planning that focus on quantitative trends for three primary drivers with high impact and high uncertainty: manifestations of climate change, social-political shifts at a global level, and forces of local value and power structures. This scenario-planning exercise underscored the complex relation between the temporospatial scale of the production of ecological goods and services and the institutional scale at which they are managed. We then guided the partners through an assessment of the relevant strengths and weaknesses of the Cape Romain Partnership for Coastal Protection, using the threats and opportunities characterized by each scenario to understand how the partnership might respond when attempting to meet conservation and societal objectives. The partnership identified key strengths including partnership experience, outreach and technical capacities, a substantial conservation land base, and high social cohesion in the South Carolina Lowcountry. Limited communication expertise, institutional inertia, and insufficient staffing and funding were recognized as important weaknesses across the partnership. By examining and scoring combinations of internal strengths and weaknesses and external threats and opportunities, the partnership developed sets of prioritized strategies to consider in the context of a given scenario. Although we had insufficient time to examine all scenarios in detail, the intent was to identify a portfolio of strategic actions to address threats and opportunities represented in multiple plausible futures. Top-ranking strategies encompassed a range of actions that focused on strengthening the conservation community and communicating the benefits of nature (that is, ecosystem services) to leveraging partnerships to expand land protection. This report also details the methods and preliminary results of several models developed or applied in support of this project. Two parcel-selection algorithms were used to evaluate anticipated habitat changes and patterns of urban growth to guide decisions on optimal conservation reserve design to protect habitat communities. One approach used a widely available planning software (MARXAN) to maximize conservation benefits near the Cape Romain NWR, whereas the other approach was a novel application of economic theory to account for uncertainty in future conditions and for the risks of unanticipated habitat loss. This latter model applies modern portfolio theory to estimate the risk of investing in any portfolio of land parcels (that is, candidate “reserves”) under climate-change uncertainty by quantifying the variation and spatial correlation of conservation benefits derived from each portfolio. We expanded the range of actions beyond simply whether or not to invest in a set of land parcels, an approach commonly used in spatial conservation planning, to also include consideration of divestment from currently protected lands. Such refinements allow for better accounting of system dynamics and can evaluate the benefits of flexible conservation tools such as rolling easements. Model results were conditional on a decision maker’s risk tolerance but highlighted general strategies of land conservation to increase future habitat representation beyond what is expected under the current protected land base. We built models that may help inform coastal planning by estimating salinity dynamics and the performance of oyster reef restoration efforts to predict the combined effects of global change and management of freshwater flows on coastal habitats and the processes that contribute to their resilience. These models can support restoration decisions by evaluating the expected benefits of site locations for shoreline protection and fisheries production. Lastly, we developed a spatially explicit economic model that predicts feedback dynamics among land value, land-use change, and effects on ecosystem service provision to explore zoning policies and incentives on urban growth and ecosystem services. We summarize these efforts with insights and considerations for the Cape Romain Partnership for Coastal Protection to continue to engage stakeholders in effective adaptation planning. First, notions of place attachment (referred to as sense of place), and the role of culture in social discourse are increasingly being used to understand the complex interactions between society and the environment and how societies respond and adapt to climate change. Sense of place was a unifying theme whenever the future of the South Carolina Lowcountry was discussed. The contribution of the South Carolina Lowcountry’s environmental wealth, rich cultural heritage, and quality of life to sense of place has important implications for how adaptation planning might best be pursued. More community-based governance of the commons (in other words, natural and cultural resources held in common), in which broad stakeholder participation and power sharing are key elements, is considered important. This devolution of governance is characterized by polycentric institutions and self-organizing social networks that promote a local culture of knowledge sharing, problem solving, and learning. These so-called bridging organizations (or individuals) often provide the leadership necessary to bring together potentially disparate Government agencies and institutions, private organizations, and individuals in a collective process of problem solving. Our observations also suggest that the conservation community in the South Carolina Lowcountry views its activities as integral to the broader governance of social-ecological systems, in which responses to the forces of global change are mediated through culture, economics, and politics. Rather than directly competing with other interests, the South Carolina Lowcountry conservation community seems to embrace an interpretation of conservation in which the fundamental objective is the quality of human life rather than environmental protection. Fundamental to the types of governance reforms described above is the notion of coproduction, in which experts and users collaborate to develop a shared body of knowledge. In this approach, scientists work with stakeholders to help frame questions, design research, and collect and analyze data. Such sustained collaborations are increasingly believed to be an effective way to produce useable (or actionable) science. The emphasis on social learning, leveraging strong social networks, coordinating and deliberating among diverse stakeholders, and applying principles of adaptive management is an essential contribution to adaptive capacity. The diverse and robust set of scientific approaches, methods to help stakeholders collaborate in effective and goal-driven planning processes, and decision tools resulting from this project hopefully will assist Cape Romain NWR and its partners prepare for climatic, ecological, and social changes over the coming decades.

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