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At least 1,675 records · Page 93Linked to original sources
USGS1982

Developing a state water plan: Ground-water conditions in Utah, spring of 1982

This is the nineteenth in a series of annual reports that describe ground-water conditions in Utah. Reports in this series, published cooperatively by the U.S. Geological Survey and the Utah Division of Water Resources, provide data to enable interested parties to keep abreast of changing ground-water conditions. This report, like the others in the series, contains information on well construction, ground-water withdrawals from wells, water-level changes, and related changes in precipitation and streamflow. Supplementary data such as graphs showing chemical quality of water and maps showing ground-water level contours are included in reports of this series only for those years or areas for which applicable data are available and are important to a discussion of changing ground-water conditions. This report includes individual discussions of selected major areas of ground-water development in the State for the calendar year 1981. Water-level fluctuations, however, are described for the periiod spring 1981 to spring 1982. Much of the data used in this report were collected by the U.S. Geological Survey in cooperation with the Division of Water Rights, Utah Department of Natural Resources.

Utah↗
USGS2006

Guidelines and standard procedures for continuous water-quality monitors: Station operation, record computation, and data reporting

The U.S. Geological Survey uses continuous water-quality monitors to assess the quality of the Nation's surface water. A common monitoring-system configuration for water-quality data collection is the four-parameter monitoring system, which collects temperature, specific conductance, dissolved oxygen, and pH data. Such systems also can be configured to measure other properties, such as turbidity or fluorescence. Data from sensors can be used in conjunction with chemical analyses of samples to estimate chemical loads. The sensors that are used to measure water-quality field parameters require careful field observation, cleaning, and calibration procedures, as well as thorough procedures for the computation and publication of final records. This report provides guidelines for site- and monitor-selection considerations; sensor inspection and calibration methods; field procedures; data evaluation, correction, and computation; and record-review and data-reporting processes, which supersede the guidelines presented previously in U.S. Geological Survey Water-Resources Investigations Report WRIR 00-4252. These procedures have evolved over the past three decades, and the process continues to evolve with newer technologies.

Techniques and Methods↗
USGS1998

Nitrate and pesticides in ground water in the eastern San Joaquin Valley, California : Occurrence and trends

The occurrence of nitrate and pesticides in ground water in California's eastern San Joaquin Valley may be greatly influenced by the long history of intensive farming and irrigation and the generally permeable sediments. This study, which is part of the U.S. Geological Survey National Water-Quality Assessment Program, was done to assess the quality of the ground water and to do a preliminary evaluation of the temporal trends in nitrate and pesticides in the alluvial fans of the eastern San Joaquin Valley. Ground-water samples were collected from 30 domestic wells in 1995 (each well was sampled once during 1995). The results of the analyses of these samples were related to various physical and chemical factors in an attempt to understand the processes that control the occurrence and the concentrations of nitrate and pesticides. A preliminary evaluation of the temporal trends in the occurrence and the concentration of nitrate and pesticides was done by comparing the results of the analyses of the 1995 ground-water samples with the results of the analyses of the samples collected in 1986-87 as part of the U.S. Geological Survey Regional Aquifer-System Analysis Program. Nitrate concentrations (dissolved nitrate plus nitrite, as nitrogen) in ground water sampled in 1995 ranged from less than 0.05 to 34 milligrams per liter, with a median concentration of 4.6 milligrams per liter. Nitrate concentrations exceeded the maximum contaminant level of 10 milligrams per liter (as nitrogen) in 5 of the 30 ground-water samples (17 percent), whereas 12 of the 30 samples (40 percent) had nitrate concentrations less than 3.0 milligrams per liter. The high nitrate concentrations were associated with recently recharged, well-oxygenated ground water that has been affected by agriculture (indicated by the positive correlations between nitrate, dissolved-oxygen, tritium, and specific conductance). Twelve pesticides were detected in 21 of the 30 ground-water samples (70 percent) in 1995, although only 5 pesticides were detected in more than 10 percent of the ground-water samples. All 12 pesticides were detected at concentrations below the maximum contaminant levels, except the banned soil fumigants 1,2-dibromo-3-chloropropane (3 detections) and 1,2-dibromoethane (1 detection). Atrazine and desethyl atrazine (a transformation product of atrazine) were the most frequently detected pesticides; they were detected in 11 ground-water samples. The frequent detections of atrazine and desethyl atrazine may be related either to past applications of atrazine or to recent application on rights-of-way. Simazine was detected in 10 ground-water samples and diuron was detected in 4 ground-water samples. The detections of simazine and diuron are generally consistent with their reported applications on the crops near the wells where they were detected. 1,2,3-trichloropropane, a manufacturing by-product of 1,2-dichloropropane and 1,3- dichloropropene formulations, was detected in 4 ground-water samples. The occurrence of 1,2,3-trichloropropane, 1,2-dibromo-3-chloropropane, and 1,2-dibromoethane is probably related to past use. Similar to nitrate concentrations, pesticide occurrence was positively correlated to dissolved-oxygen concentrations, indicating that areas with high dissolved-oxygen concentrations may be vulnerable to contamination by nitrate and pesticides. High dissolved-oxygen concentrations may be associated with water that has been rapidly recharged. A comparison of the concentrations and the occurrence of nitrate and pesticides between 1986-87 and 1995 indicates that nitrate concentrations may pose a greater threat to the quality of the ground-water resource in this region than pesticides, in the context of current drinking-water standards. Nitrate concentrations were significantly higher in the 1995 ground-water samples than in the 1986-87 samples collected from the same wells.

Calfornia↗
USGS1986

Developing a state water plan: Ground-water conditions in Utah, spring of 1986

This is the twenty-third in a series of annual reports that describe ground-water conditions in Utah. Reports in this series, published cooperatively by the U.S. Geological Survey and the Utah Division of Water Resources, provide data to enable interested parties to keep abreast of changing ground-water conditions. This report, like the others in the series, contains information on well construction, ground-water withdrawals from wells, water-level changes, and related changes in precipitation and streamflow. Supplementary data such as graphs showing chemical quality of water and maps showing water-level contours are included in reports of this series only for those years or areas for which applicable data are available and are important to a discussion of changing ground-water conditions. This report includes individual discussions of selected major areas of ground-water development in the State for the calendar year 1985. Water-level fluctuations, however, are described from the spring of 1985 to the spring of 1986. Much of the data used in this report were collected by the U.S. Geological Survey in cooperation with the Division of Water Rights, Utah Department of Natural Resources.

Utah↗
USGS1988

Developing a state water plan: Ground-water conditions in Utah, spring of 1988

This is the twenty-fifth in a series of annual reports that describe ground-water conditions in Utah. Reports in this series, published cooperatively by the U.S. Geological Survey and the Utah Division of Water Resources, provide data to enable interested parties to keep abreast of changing ground-water conditions. This report, like the others in the series, contains information on well construction, ground-water withdrawals from wells, water-level changes, and related changes in precipitation and streamflow. Supplementary data such as graphs showing chemical quality of water and maps showing water-level contours are included in reports of this series only for those years or areas for which applicable data are available and are important to a discussion of changing ground-water conditions. This report includes individual discussions of selected major areas of ground-water development in the State for the calendar year 1987. Water-level fluctuations, however, are described from the spring of 1987 to the spring of 1988. Much of the data used in this report were collected by the U.S. Geological Survey in cooperation with the Division of Water Rights, Utah Department of Natural Resources.

Utah↗
USGS1989

Ground-water conditions in Utah, spring of 1989

This is the twenty-sixth in a series of annual reports that describe ground-water conditions in Utah. Reports in this series, published cooperatively by the U.S. Geological Survey and the Utah Division of Water Resources, provide data to enable interested parties to keep abreast of changing ground-water conditions. This report, like the others in the series, contains information on well construction, ground-water withdrawal from wells, water-level changes, and related changes in precipitation and streamflow. Supplementary data such as graphs showing chemical quality of water and maps showing water-level contours are included in reports of this series only for those years or areas for which applicable data are available and are important to a discussion of changing ground-water conditions. This report includes individual discussions of selected major areas of ground-water development in the State for the calendar year 1988. Water-level fluctuations, however, are described from the spring of 1988 to the spring of 1989. Much of the data used in this report were collected by the U.S. Geological Survey in cooperation with the Division of Water Rights, Utah Department of Natural Resources.

Utah↗
USGS2010

Groundwater conditions in Utah, spring of 2010

This is the forty-seventh in a series of annual reports that describe groundwater conditions in Utah. Reports in this series, published cooperatively by the U.S. Geological Survey and the Utah Department of Natural Resources, Division of Water Resources and Division of Water Rights, and the Utah Department of Environmental Quality, Division of Water Quality, provide data to enable interested parties to maintain awareness of changing groundwater conditions. This report, like the others in the series, contains information on well construction, groundwater withdrawal from wells, water-level changes, precipitation, streamflow, and chemical quality of water. Information on well construction included in this report refers only to wells constructed for new appropriations of groundwater. Supplementary data are included in reports of this series only for those years or areas which are important to a discussion of changing groundwater conditions and for which applicable data are available. This report includes individual discussions of selected significant areas of groundwater development in the State for calendar year 2009. Most of the reported data were collected by the U.S. Geological Survey in cooperation with the Utah Department of Natural Resources, Division of Water Resources and Division of Water Rights, and the Utah Department of Environmental Quality, Division of Water Quality. This report is also available online at http://www. waterrights.utah.gov/techinfo/ and http://ut.water.usgs.gov/ publications/GW2010.pdf. Groundwater conditions in Utah for calendar year 2008 are reported in Burden and others (2009) and available online at http://ut.water.usgs.gov/publications/ GW2009.pdf. Analytical results associated with water samples collected from each area of groundwater development were compared to State of Utah maximum contaminant levels (MCLs) and secondary drinking-water standards of routinely measureable substances present in water supplies. The MCLs and secondary drinking-water standards can be accessed online at http://www.rules.utah.gov/publicat/code/r309/r309-200. htm#T5. The U.S. Environmental Protection Agency (EPA) drinking-water standards can be accessed at http://www.epa. gov/safewater/mcl.html#mcls. Maximum contaminant levels and secondary drinking-water standards were developed for public water systems and do not apply to the majority of wells sampled during this study. Every 5 years, this report series includes maps depicting comparisons of 30-year changes in water levels for each of the major areas of groundwater development. The water-level change maps in this report show the difference between water levels measured in 1980 and in 2010. Water-level rises or declines occurring on shorter time scales are shown in plots of annual water-level measurements for several wells in each of the major areas of groundwater development.

Utah↗
USGS1984

Developing a state water plan: Ground-water conditions in Utah, spring of 1984

This is the twenty-first in a series of annual reports that describe ground-water conditions in Utah. Reports in this series, published cooperatively by the U.S. Geological Survey and the Utah Division of Water Resources, provide data to enable interested parties to keep abreast of changing ground-water conditions. This report, like the others in the series, contains information on well construction, ground-water withdrawals from wells, water-level changes, and related changes in precipitation and streamflow. Supplementary data such as graphs showing chemical quality of water and maps showing ground-water level contours are included in reports of this series only for those years or areas for which applicable data are available and are important to a discussion of changing ground-water conditions. This report includes individual discussions of selected major areas of ground-water development in the State for the calendar year 1983. Water-level fluctuations, however, are described from the spring of 1983 to the spring of 1984. Much of the data used in this report were collected by the U.S. Geological Survey in cooperation with the Division of Water Rights, Utah Department of Natural Resources.

Utah↗
USGS1985

Developing a state water plan: Ground-water conditions in Utah, spring of 1985

This is the twenty-second in a series of annual reports that describe ground-water conditions in Utah. Reports in this series, published cooperatively by the U.S. Geological Survey and the Utah Division of Water Resources, provide data to enable interested parties to keep abreast of changing ground-water conditions. This report, like the others in the series, contains information on well construction, ground-water withdrawals from wells, water-level changes, and related changes in precipitation and streamflow. Supplementary data such as graphs showing chemical quality of water and maps showing ground-water level contours are included in reports of this series only for those years or areas for which applicable data are available and are important to a discussion of changing ground-water conditions. This report includes individual discussions of selected major areas of ground-water development in the State for the calendar year 1984. Water-level fluctuations, however, are described from the spring of 1984 to the spring of 1985. Much of the data used in this report were collected by the U.S. Geological Survey in cooperation with the Division of Water Rights, Utah Department of Natural Resources.

Utah↗
USGS1967

Hydrogeologic data for the Shetucket River basin, Connecticut

This report presents hydrologic and geologic data collected by the U.S. Geological Survey during an investigation of water resources in the Shetucket River basin of Connecticut in cooperation with the Connecticut Water Resources Commission. The Shetucket River basin occupies about 507 square miles in the eastern part of the State, including the towns of Andover, Ashford, Chaplin, Coventry, Mansfield, Scotland, Sprague, Windham, and Willington, and parts of Bolton, Canterbury, Columbia, Eastford, Ellington, Franklin, Lebanon, Lisbon, Hampton, Hebron, Norwich, Pomfret, Stafford, Tolland, Union, Vernon, and Woodstock. A companion interpretive report, Connecticut Water Resources Bulletin ll, (Thomas, and others, 1967), evaluates the water resources of the basin. The data on the following pages serve to document and supplement that report and should be especially useful in planning the development of water resources at specific localities. Data were collected as part of this investigation during the period July 1962 through December 1964. Streamflow records from continuous-record gaging stations in the basin for this period have been published annually along with data from other parts of the State in a series of U.S. Geological Survey reports entitled "Surface Water Records of Connecticut." Water-level measurements in wells throughout the State from 1960 through 1964, including those made as part of this investigation, are published in Connecticut Water Resources Bulletin 7 (Meikle and Baker, 1965). Most other data collected during this investigation are tabulated on the following pages. Included are some well records and chemical analyses of water samples collected prior to July 1962 and not previously published. The locations of sites at which data were collected are shown on plate A in the pocket at the back of the report. Plate A includes the locations of 98 sites where 2 to 6 miscellaneous measurements of streamflow were made during 1963 and 13 other sites where continuous records are maintained. Data for these sites have already been published in "Surface Water Records of Connecticut" and are not repeated here. Data presented~ unless otherwise noted, were collected by U.S. Geological Survey personnel.

Connecticut↗
USGS2007

Groundwater geochemistry in the Seminole Well Field, Cedar Rapids, Iowa

The City of Cedar Rapids obtains its municipal water supply from four well fields in an alluvial aquifer along the Cedar River in east-central Iowa. Since 1992, the City and the U.S. Geological Survey have cooperatively studied the groundwater-flow system and water chemistry near the well fields. The geochemistry in the alluvial aquifer near the Seminole Well Field was assessed to identify potentially reactive minerals and possible chemical reactions that produce observed changes in water chemistry. Calcite, dolomite, ferrihydrite, quartz, rhodochrosite, and siderite were identified as potentially reactive minerals by calculating saturation indexes. Aluminosiicate minerals including albite, Ca-montmorillonite, gibbsite, illite, K-feldspar, and kaolinite were identified as potentially reactive minerals using hypothetical saturation indexes calculated with an assumed dissolved aluminum concentration of 1 microgram per liter. Balanced chemical equations derived from inverse-modeling techniques were used to assess chemical reactions as precipitation percolates to the water table. Calcite dissolution was predominate, but aluminosilicate weathering, cation exchange, and redox reactions also likely occurred. Microbial-catalyzed redox reactions altered the chemical composition of water infiltrating from the Cedar River into the alluvial aquifer by consuming dissolved oxygen, reducing nitrate, and increasing dissolved iron and manganese concentrations. Nitrate reduction only occurred in relatively shallow (3 to 7 meters below land surface) groundwater near the Cedar River and did not occur in water infiltrating to deeper zones of the alluvial aquifer.

Iowa↗
USGS1999

Paleohydrogeology of the San Joaquin basin, California

Mass transport can have a significant effect on chemical diagenetic processes in sedimentary basins. This paper presents results from the first part of a study that was designed to explore the role of an evolving hydrodynamic system in driving mass transport and chemical diagenesis, using the San Joaquin basin of California as a field area. We use coupled hydrogeologic models to establish the paleohydrogeology, thermal history, and behavior of nonreactive solutes in the basin. These models rely on extensive geological information and account for variable-density fluid flow, heat transport, solute transport, tectonic uplift, sediment compaction, and clay dehydration.

California↗
USGS2000

Associations among fish assemblage structure and environmental variables in Willamette Basin streams, Oregon

As part of the U.S. Geological Survey's National Water-Quality Assessment Program, fish were collected from 24 selected stream sites in the Willamette Basin during 1993-1995 to determine the composition of the fish assemblages and their relation to the chemical and physical environment. Variance in fish relative abundance was greater among all sites than among spatially distinct reaches within a site (spatial variation) or among multiple sampled years at a site (temporal variation). Therefore, data from a single reach in an individual year was considered to be a reliable estimator of the fish assemblage structure at a site when the data were normalized by percent relative abundance. Multivariate classification and ordination were used to examine patterns in environmental variables and fish relative abundance over differing spatial scales (among versus within ecoregions). Across all ecoregions (all sites), fish assemblages were primarily structured along environmental gradients of water temperature and stream gradient (coldwater, high-gradient forested sites versus warmwater, low-gradient Willamette Valley sites); this pattern superseded patterns that were ecoregion specific. Water temperature, dissolved oxygen, and physical habitat (e.g., riparian canopy and percent riffles) were associated with patterns of fish assemblages across all ecoregions; however, pesticide and total phosphorus concentrations were more important than physical habitat within the Willamette Valley ecoregion. Consideration of stream site stratification (e.g., stream size, ecoregion, and stream gradient), identification of fish to species level (particularly the sculpin family), and detailed measurement of habitat, diurnal dissolved oxygen, and water temperature were critical in evaluating the composition of fish assemblages in relation to land use. In general, these low-gradient valley streams typical of other agricultural regions had poor riparian systems and showed increases in water temperature, nutrients, and fine grain sediments that were associated with degradation in the native fish assemblages. There was an association of high abundances of introduced species and high percent external abnormalities in medium-sized river sites of mixed land use and high abundances of tolerant species in small streams of predominantly agricultural land use.

Oregon↗
USGS2009

Sediment characterization and dynamics in Lake Pontchartrain, Louisiana

Lake Pontchartrain in southeastern Louisiana is the largest of several shallow estuaries that together cover over 15,000 km 2 . Wetlands, forests, and large urban areas surround the lake. Primary transport mechanisms of sediments to Lake Pontchartrain include urban runoff, major diversions of the Mississippi River, discharge from streams along the north and west shores, and tidal circulation. Sediments deposited in Lake Pontchartrain are subjected to resuspension and mixing by natural and human activities. Bioturbation and water turbulence throughout the lake are the major mixing agents, and mechanical shell dredging has reworked much of the lake bottom over the last century. Sediment characterization through direct sampling and geophysical surveys indicates that these processes continually rework the top meter of sediment. The lake receives discharge from roadways and industrial and agricultural sources. Contaminants from these sources accumulate in the lake sediments and are an important contributor to the degradation of the estuary. Decline in populations of various benthic organisms, such as shrimp and clams, has been documented in the lake. To characterize the health of this important estuary, the U.S. Geological Survey (USGS) conducted a comprehensive evaluation of the geology, geomorphology, coastal processes, and environmental condition of the Pontchartrain Basin from 1994 to 1997. This report presents an assessment of sediment distribution and quality using a multidisciplinary approach to characterize the influence of various physical and chemical parameters: nearsurface stratigraphy, major trace metal concentrations (Cu, Pb, Zn, and Ni), and short-lived radionuclides ( 210 Pb, 7 Be, and 137 Cs). The results are compared with water-circulation patterns to determine high-resolution sedimentation patterns in the lake. The data show a significant increase in trace metals in the top 1 m of lake sediments. Above this horizon, pollen analysis indicates a correlation with land clearing in the area, a proxy for increasing human development of the surrounding landscape and an increase in surface run-off. The data also show that the top meter of sediment undergoes frequent resuspension during high-energy circulation events and via circulation gyres in the lake. This regular turnover does not allow stratification of recently deposited sediments, restricting the sequestration of contaminated material that enters the lake.

Louisiana↗
USGS2007

Characterization of flood sediments from Hurricanes Katrina and Rita and potential implications for human health and the environment

The flooding in the greater New Orleans, La., area that resulted from Hurricanes Katrina and Rita in August and September 2005 left behind accumulations of sediments up to many centimeters thick on streets, lawns, parking lots, and other flat surfaces (fig. 1). During the flood dewatering and subsequent cleanup, there were concerns that these sediments might contain pathogens and chemical contaminants that would pose a health risk to emergency responders, cleanup workers, and local residents who came into contact with the wet sediments or inhaled dusts generated from dried sediments. In response to these concerns, U.S. Geological Survey (USGS) scientists and colleagues characterized the potential environmental and health hazards of hurricane flood sediments from the greater New Orleans and Slidell, La., area.

Louisiana↗
USGS2010

Sustainability of natural attenuation of nitrate in agricultural aquifers

Increased concentrations of nitrate in groundwater in agricultural areas, coinciding with increased use of chemical and organic fertilizers, have raised concern because of risks to environmental and human health. At some sites, these problems are mitigated by natural attenuation of nitrate as a result of microbially mediated reactions. Results from U.S. Geological Survey (USGS) research under the National Water-Quality Assessment (NAWQA) program show that reactions of dissolved nitrate with solid aquifer minerals and organic carbon help lower nitrate concentrations in groundwater beneath agricultural fields. However, increased fluxes of nitrate cause ongoing depletion of the finite pool of solid reactants. Consumption of the solid reactants diminishes the capacity of the aquifer to remove nitrate, calling into question the long-term sustainability of these natural attenuation processes.

Fact Sheet↗
USGS2012

Trace-element analyses of core samples from the 1967-1988 drillings of Kilauea Iki lava lake, Hawaii

This report presents previously unpublished analyses of trace elements in drill core samples from Kilauea Iki lava lake and from the 1959 eruption that fed the lava lake. The two types of data presented were obtained by instrumental neutron-activation analysis (INAA) and energy-dispersive X-ray fluorescence analysis (EDXRF). The analyses were performed in U.S. Geological Survey (USGS) laboratories from 1989 to 1994. This report contains 93 INAA analyses on 84 samples and 68 EDXRF analyses on 68 samples. The purpose of the study was to document trace-element variation during chemical differentiation, especially during the closed-system differentiation of Kilauea Iki lava lake.

Hawai'i↗
USGS2021

Linear regression model documentation and updates for computing water-quality constituent concentrations or densities using continuous real-time water-quality data for the Kansas River, Kansas, July 2012 through September 2019

The Kansas River provides drinking water to about 800,000 people in northeastern Kansas. Water-treatment facilities that use the Kansas River as a water-supply source use chemical and physical processes during water treatment to remove contaminants before public distribution. Advanced notification of changing water-quality conditions near water-supply intakes allows water-treatment facilities to proactively adjust treatment. The U.S. Geological Survey (USGS), in cooperation with the Kansas Water Office (funded in part through the Kansas Water Plan), the Kansas Department of Health and Environment, The Nature Conservancy, the City of Lawrence, the City of Manhattan, the City of Olathe, the City of Topeka, and Johnson County WaterOne, collected water-quality data at the Kansas River at Wamego (USGS site 06887500; hereafter referred to as the “Wamego site”) and De Soto (USGS site 06892350; hereafter referred to as the “De Soto site”) monitoring sites to update previously published regression models relating continuous water-quality sensor measurements, streamflow, and seasonal components to discretely sampled water-quality constituent concentrations or densities. Linear regression analysis was used to update and develop models for total dissolved solids, major ions, hardness as calcium carbonate, nutrients (nitrogen and phosphorus species), chlorophyll a , total suspended solids, suspended sediment, and fecal indicator bacteria at the Wamego and De Soto monitoring sites using data collected during July 2012 through September 2019. The water-quality information documented in this report can be used as guidance for water-treatment processes and to characterize changes in water-quality conditions in the Kansas River over time that would not be otherwise possible.

Kansas↗