Geology Reports⌕ Search

SEARCH · Geology Reports

Results for “Water-Resources Report”

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

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

At least 1,063 records · Page 59Linked to original sources
USGS2002

Surface water-ground water interactions along the lower Dungeness River and vertical hydraulic conductivity of streambed sediments, Clallam County, Washington, September 1999-July 2001

The Dungeness River emerges from the Olympic Mountains and flows generally north toward the Strait of Juan De Fuca, crossing the broad, fertile alluvial fan of the Sequim-Dungeness peninsula in northeastern Clallam County, Washington. Increasing competition for the peninsula's ground-water resources, changing water-use patterns, and recent requirements to maintain minimum in-stream flows to enhance endangered salmon and trout populations have severely strained the peninsula's water resources and necessitated a better understanding of the interaction between surface water and groundwater. Three methods were used to characterize the interchange between surface water and groundwater along the lower 11.8 miles of the Dungeness River corridor between September 1999 and July 2001. In-stream mini-piezometers were used to measure vertical hydraulic gradients between the river and the water-table aquifer at 27 points along the river and helped to define the distribution of gaining and losing stream reaches. Seepage runs were used to quantify the net volume of water exchanged between the river and ground water within each of five river reaches, termed 'seepage reaches.' Continuous water-level and water-temperature monitoring at two off-stream well transects provided data on near-river horizontal hydraulic gradients and temporal patterns of water exchange for a representative gaining stream reach and a representative losing stream reach. Vertical hydraulic gradients in the mini-piezometers generally were negative between river miles 11.8 and 3.6, indicating loss of water from the river to ground water. Gradients decreased in the downstream direction from an average of -0.86 at river mile 10.3 to -0.23 at river mile 3.7. Small positive gradients (+0.01 to +0.02) indicating ground-water discharge occurred in three localized reaches below river mile 3.7. Data from the seepage runs and off-stream transect wells supported and were generally consistent with the mini-piezometer findings. An exception occurred between river miles 8.1 and 5.5 where seepage results showed a small gain and the mini-piezometers showed negative gradients. Vertical hydraulic conductivity of riverbed sediments was estimated using hydraulic gradients measured with the mini-piezometers and estimated seepage fluxes. The resulting conductivity values ranged from an average of 1 to 29 feet per day and are similar to values reported for similar river environments elsewhere. The results of this study will be used to calibrate a transient, three-dimensional ground-water flow model of the Sequim-Dungeness peninsula. The model will be used to assess the potential effects on ground-water levels and river flows that result from future water use and land-use changes on the peninsula.

Water-Resources Investigations Report↗
USGS2002

Environmental setting and water-quality issues of the Mobile River Basin, Alabama, Georgia, Mississippi, and Tennessee

The Mobile River Basin is one of over 50 river basins and aquifer systems being investigated as part of the U.S. Geological Survey National Water-Quality Assessment (NAWQA) Program. This basin is the sixth largest river basin in the United States, and fourth largest in terms of streamflow, encompassing parts of Alabama, Georgia, Mississippi, and Tennessee. Almost two-thirds of the 44,000-square-mile basin is located in Alabama. Extensive water resources of the Mobile River Basin are influenced by an array of natural and cultural factors. These factors impart unique and variable qualities to the streams, rivers, and aquifers providing abundant habitat to sustain the diverse aquatic life in the basin. Data from Federal, State, and local agencies provide a description of the environmental setting of the Mobile River Basin. Environmental data include natural factors such as physiography, geology, soils, climate, hydrology, ecoregions, and aquatic ecology, and human factors such as reservoirs, land use and population change, water use, and water-quality issues. Characterization of the environmental setting is useful for understanding the physical, chemical, and biological characteristics of surface and ground water in the Mobile River Basin and the possible implications of that environmental setting for water quality. The Mobile River Basin encompasses parts of five physiographic provinces. Fifty-six percent of the basin lies within the East Gulf section of the Coastal Plain Physiographic Province. The remaining northeastern part of the basin lies, from west to east, within the Cumberland Plateau section of the Appalachian Plateaus Physiographic Province, the Valley and Ridge Physiographic Province, the Piedmont Physiographic Province, and the Blue Ridge Physiographic Province. Based on the 1991 land-use data, about 70 percent of the basin is forested, while agriculture, including livestock (poultry, cattle, and swine), row crops (cotton, corn, soybeans, sorghum, and wheat), and pasture land accounts for about 26 percent of the study unit. Agricultural land use is concentrated along the Black Prairie Belt district of the Coastal Plain. Urban areas account for only 3 percent of the total land use; however, the areal extent of the metropolitan statistical areas (MSA) may indicate more urban influences. The MSAs include urban areas outside of the city boundaries and can include adjacent counties. Seven MSAs are delineated in the Mobile River Basin, including Montgomery, Mobile, Tuscaloosa, Birmingham, Gadsden, Anniston, and Atlanta. The total population for the Mobile River Basin was about 3,673,100 in 1990. State water-quality agencies have identified numerous causes and sources of water-body impairment in the Mobile River Basin. In 1996, organic enrichment, dissolved oxygen depletion, elevated nutrient concentrations, and siltation were the most frequently cited causes of impairment, affecting the greatest number of river miles. Bacteria, acidic pH, and elevated metal concentrations also were identified as causes of impairment. The sources for impairment varied among river basins, were largely a function of land use, and were attributed primarily to municipal and industrial sources, mining, and agricultural activities.

Water-Resources Investigations Report↗
USGS2002

Priority-pollutant trace elements in streambed sediments of the Cook Inlet basin, Alaska, 1998-2000

Trace element concentrations in 48 streambed sediment samples collected at 47 sites in the Cook Inlet Basin, Alaska, were compared to concentrations from studies in the conterminous United States using identical methods and to Probable Effect Concentrations. Concentrations of arsenic, chromium, mercury, and nickel in the 0.063-mm size fraction of streambed sediments from the Cook Inlet Basin were elevated relative to reference sites in the conterminous United States. Concentrations of cadmium, lead, and zinc were highest at the most urbanized site in Anchorage and at two sites downstream from an ore body in Lake Clark National Park and Preserve. At least 35 percent of the 48 samples collected in the Cook Inlet Basin exceeded the Probable Effect Concentration for arsenic, chromium, or nickel. More than 50 percent of the samples were considered to have low potential toxicity for cadmium, lead, mercury, nickel, selenium, and zinc. A Probable Effect Concentration quotient that reflects the combined toxicity of arsenic, cadmium, chromium, copper, lead, mercury, nickel, and zinc was exceeded in 44 percent of the samples from the Cook Inlet Basin. The potential toxicity was high in the Denali and Lake Clark National Parks and Preserves where organic carbon concentrations in streambed sediments were low. However, potential toxicity results should be considered in context with the very small amounts of fine-grained sediment present in the streambed sediments of the Cook Inlet Basin.

Water-Resources Investigations Report↗
USGS2002

Detection of fresh ground water and a contaminant plume beneath Red Brook Harbor, Cape Cod, Massachusetts, 2000

Trichloroethene and tetrachloroethene were detected in ground water in a vertical interval from about 68 to 176 feet below sea level beneath the shoreline where the contaminant plume emanating from a capped landfill on the Massachusetts Military Reservation intersects Red Brook Harbor. The highest concentrations at the shoreline, about 15 micrograms per liter of trichloroethene and 1 microgram per liter of tetrachloroethene, were measured in samples from one well at about 176 feet below sea level. The concentrations of nutrients, such as nitrate and ammonium, and trace metals, such as iron and manganese, in these same samples are typical of uncontaminated ground water on Cape Cod. Fresh ground water (bulk electrical conductance less than 100 millisiemens per meter) is present beneath the harbor at 40 of 48 locations investigated within about 250 feet of the shoreline. Fresh ground water also was detected at one location approximately 450 feet from shore. The harbor bottom consists of soft sediments that range in thickness from 0 to greater than 20 feet and overlie sandy aquifer materials. Trichloroethene was detected at several locations in fresh ground water from the sandy aquifer materials beneath the harbor. The highest trichloroethene concentration, about 4.5 micrograms per liter, was measured about 450 feet from shore.

Massachusetts↗
USGS2002

Hydrogeology, ground-water use, and ground-water levels in the Mill Creek Valley near Evendale, Ohio

Withdrawals of ground water in the central Mill Creek Valley near Evendale, Ohio, caused water-level declines of more than 100 feet by the 1950s. Since the 1950s, management practices have changed to reduce the withdrawals of ground water, and recovery of water levels in long-term monitoring wells in the valley has been documented. Changing conditions such as these prompted a survey of water use, streamflow conditions, and water levels in several aquifers in the central Mill Creek Valley, Hamilton and Butler Counties, Ohio. Geohydrologic information, water use, and water levels were compiled from historical records and collected during the regional survey. Data collected during the survey are presented in terms of updated geohydrologic information, water use in the study area, water levels in the aquifers, and interactions between ground water and surface water. Some of the data are concentrated at former Air Force Plant 36 (AFP36), which is collocated with the General Electric Aircraft Engines (GEAE) plant, and these data are used to describe geohydrology and water levels on a more local scale at and near the plant. A comparison of past and current ground-water use and levels indicates that the demand for ground water is decreasing and water levels are rising. Before 1955, most of the major industrial ground-water users had their own wells, ground water was mined from a confined surficial (lower) aquifer, and water levels were more than 100 feet below their predevelopment level. Since 1955, however, these users have been purchasing their water from the city of Cincinnati or a private water purveyor. The cities of Reading and Lockland, both producers of municipal ground-water supplies in the area, shut down their well fields within their city limits. Because the demand for ground-water supplies in the valley has lessened greatly since the 1950s, withdrawals have decreased, and, consequently, water levels in the lower aquifer are 65 to 105 feet higher than they were in 1955. During the time of the water-level survey (November 2000), ground water was being pumped from four locations in the lower aquifer, including three municipalities and one remediation site. Effects of pumping in those four areas were evident from the regional water-level data. Overall, the direction of ground-water flow in the lower aquifer is from northeast to southwest along the primary orientation of the Mill Creek Valley in the study area. Water levels in shallower surficial aquifers were mapped at local scales centered on GEAE. Examination of well logs indicated that these aquifers (called shallow and water-table) are discontinuous and, on a regional scale, few wells were completed in these aquifers. Water levels in the shallow aquifer indicated that flow was from northeast to southwest except in areas where pumping in the lower aquifer or the proximity of Mill Creek may have been affecting water levels in the shallow aquifer. Water levels in the water-table aquifer indicated flow toward Mill Creek from GEAE.

Water-Resources Investigations Report↗
USGS2002

Sedimentation Survey of Lago Guerrero, Puerto Rico, May 2001

Lago Guerrero, a small reservoir owned by the Puerto Rico Electric Power Authority, is part of the Isabela Hydroelectric System and is located in Aguadilla, in northwestern Puerto Rico. The reservoir had a storage capacity of about 127,376 cubic meters in May 2001 and a maximum depth of about 5.8 meters. Records on dam construction and original topography and storage capacity were not available; therefore, sedimentation rates could not be determined. However, Lago Guerrero resumably was constructed during the 1930?s because it receives water from lago Guajataca, which was constructed in 1928. The May 2001 bathymetric survey of Lago Guerrero established baseline data that are essential to calculate sedimentation rates, sediment yields, storage loss, and sediment deposition sites within the reservoir.

Water-Resources Investigations Report↗
USGS2002

Sediment accumulation and distribution in Lake Kampeska, Watertown, South Dakota

Lake Kampeska is a natural lake of about 5,075 acres located within the city limits of Watertown, South Dakota. The lake is important as a water supply and recreational resource. Sediment accumulation has been a concern for many years, and several studies have been conducted to learn more about the sediment, including how fast it is accumulating. This study attempted to evaluate previously estimated sediment-accumulation rates and to describe the distribution of sediment in the lake. Analysis of cesium-137 concentrations in sediment cores and changes in lake-bottom elevation over time led to the conclusion that during about the last 50 years, the sediment has been accumulating at a rate on the order of 0.01 foot per year or less. Changes in lake-bottom elevation during this time period indicate that the only significant deposition occurred in the area near the connection of Lake Kampeska to the Big Sioux River. Direct physical measurements and marine seismic surveys indicate that the flat-bottom interior part of the lake has 10 feet or more of sediment over a relatively irregular subbottom.

Water-Resources Investigations Report↗
USGS2002

Calculation of individual isotope equilibrium constants for implementation in geochemical models

Theory is derived from the work of Urey to calculate equilibrium constants commonly used in geochemical equilibrium and reaction-transport models for reactions of individual isotopic species. Urey showed that equilibrium constants of isotope exchange reactions for molecules that contain two or more atoms of the same element in equivalent positions are related to isotope fractionation factors by , where is n the number of atoms exchanged. This relation is extended to include species containing multiple isotopes, for example and , and to include the effects of nonideality. The equilibrium constants of the isotope exchange reactions provide a basis for calculating the individual isotope equilibrium constants for the geochemical modeling reactions. The temperature dependence of the individual isotope equilibrium constants can be calculated from the temperature dependence of the fractionation factors. Equilibrium constants are calculated for all species that can be formed from and selected species containing , in the molecules and the ion pairs with where the subscripts g, aq, l, and s refer to gas, aqueous, liquid, and solid, respectively. These equilibrium constants are used in the geochemical model PHREEQC to produce an equilibrium and reaction-transport model that includes these isotopic species. Methods are presented for calculation of the individual isotope equilibrium constants for the asymmetric bicarbonate ion. An example calculates the equilibrium of multiple isotopes among multiple species and phases.

Water-Resources Investigations Report↗
USGS2002

Effects of urbanization and long-term rainfall on the occurrence of organic compounds and trace elements in reservoir sediment cores, streambed sediment, and fish tissue from the Santa Ana River basin, California, 1998

Organcochlorine compounds, semivolatile-organic compounds (SVOC), and trace elements were analyzed in reservoir sediment cores, streambed sediment, and fish tissue in the Santa Ana River Basin as part of the U.S. Geological Survey's National Water-Quality Assessment Program. Three reservoirs were sampled in areas that have different degrees of urbanization. Streambed sediment and fish tissue collected at 12 sites were divided into two groups, urban and nonurban. More organochlorine compounds were detected in reservoir sediment cores, streambed sediment and fish tissue, and at higher concentrations at urban sites than at nonurban sites. At all sites, except West Street Basin, concentrations of organochlorine compounds were lower than the probable-effect concentration (PEC). At the highly urbanized West Street Basin, chlordane and p,p'-DDE exceeded the PEC throughout the historical record. The less stringent threshold-effect concentration (TEC) was exceeded for six compounds at eight sites. Most of the organochlorine compounds detected in streambed sediment and fish tissue were at urban sites on the Santa Ana River as opposed to its tributaries, suggesting accumulation and persistence in the river. More SVOCs were detected in reservoir sediment cores and streambed sediment, and at higher concentrations, at urban sites than at nonurban sites. At all the sites, except West Street Basin, concentrations of SVOCs were lower than the PEC. At West Street Basin, chrysene, pyrene, and total polycyclic-aromatic hydrocarbons exceeded the PEC throughout the historical record. The TEC was exceeded for 10 compounds at 3 sites. Most of the SVOCs were detected in streambed sediment at urban sites on tributaries to the Santa Ana River rather than the mainstem itself. The less frequent occurrence and lower concentrations in the Santa Ana River suggest that SVOCs are less persistent than organochlorine compounds, possibly as a result of volatization, gradation, or dilution. Most trace-element detections in reservoir sediment cores and streambed sediment were at urban sites, and the concentrations were generally higher than at nonurban sites. Lead and zinc exceeded their PECs at West Street Basin throughout the historical record; copper exceeded its PEC at Canyon Lake, an area of urban growth. The TEC was exceeded for 10 compounds at 11 sites. Frequency of detection and concentration did not differ between tributary and Santa Ana River sites, which may be attributed to the fact that trace elements occur naturally. Four trace elements (arsenic, copper, mercury, and selenium) had higher concentrations in fish tissue at nonurban sites than at urban sites. Concentrations decreased over time for organochlorine compounds at all three reservoirs, probably a result of the discontinued use of many of the compounds. Decreasing trends in SVOCs and trace elements were observed at West Street Basin, but increasing trends were observed at Canyon Lake. Concentrations of organochlorine compounds, SVOCs, and trace elements were higher during periods of above average rainfall at both West Street Basin and Canyon Lake.

Water-Resources Investigations Report↗
USGS2002

Interdecadal changes in the hydrometeorological regime of the Pacific Northwest and in the regional-to-hemispheric climate regimes, and their linkages

Selected hydrometeorological (HM) data for the Pacific Northwest, and regional-to-hemispheric atmospheric-circulation data and sea-surface temperature (SST) data for the North Pacific, are examined for three successive interdecadal periods that are subsets of the instrumental record in order to estimate if their characteristics have changed. The HM data included monthly precipitation totals for 50 sites in western Washington and 29 climate divisions of the Pacific Northwest, and streamflow averages for 112 sites in Washington, Oregon, and Idaho. The atmospheric data included the Southern Oscillation Index (SOI), an index of the Pacific/North America (PNA) circulation pattern, measures of the westerly and northerly components of geostrophic flow, and a subset of the Northern Hemisphere 700-millibar geopotential height data; this subset of 162 grid points includes the area between 15 degrees and 75 degrees N, 110 degrees W and 130 degrees E. The SST data are for a 5-degree grid between 20 degrees N and 60 degrees N, 110 degrees W and 130 degrees E. The atmospheric and SST data were examined not only because the HM regime is linked to regional-to-hemispheric climate regimes, but also to estimate the extent of climate shifts displayed by these data. Three subsets of the record were identified as pre-1947 (PRE), 1947-76 (BASE), and post-1976 (POST) water years, based on an analysis of the HM data and previous studies. For each subset, means were calculated for the water year (October-September), the runoff season (March-August), the winter season (October-February), and a baseflow season (August-September). Differences in means and in ratios of the means between the BASE period and the PRE and POST periods were examined for changes. Winter-season mean precipitation during both the PRE and POST periods was smaller than the BASE period, indicating a spatially consistent and distinct change in the HM regime during winter during the PRE and POST periods. For the runoff season, mean precipitation at most sites, in comparison to the BASE period, was smaller during the PRE period and larger during POST period, indicating that different HM regimes occurred during the runoff season for the PRE and POST periods. Water-year mean precipitation was less for both the PRE and POST periods because of decreases in winter-season precipitation; however, the water-year values for the POST period were not as small as those of the PRE period because more precipitation was concentrated in the runoff season. During both the PRE and POST periods, the mean water-year discharge was less than the BASE period for all but 15 of the 112 sites. Fourteen of the 15 sites were in a well-defined region (southern Idaho and southeastern Oregon), and 13 of the 14 had larger means only during the POST period. Winter-season streamflow was less for all but 11 sites during both PRE and POST periods; the largest decreases in the mean, more than 30 percent, were for an area in central Oregon. Except for the sites that had larger mean water-year discharge, runoff-season means also were less than those during the BASE period. Changes in the SOI and PNA index from the BASE period were generally similar to and consistent with those of the majority of the hydrologic data; dissimilarities were in well-defined regions and are attributed to the evolutionary nature of the regime shifts. Negative values of the SOI for the POST period were more persistent than those that have occurred during both the PRE and BASE periods. The changes in the PNA index and the geostrophic flow components during the POST period are consistent with drier and warmer conditions in the Pacific Northwest. The 700-millibar data display trends and differences between the BASE and POST periods; differences in composite anomalies for selected winter months between these periods show a well-defined PNA pattern. For many areas of the North Pacific, the record of SSTs shows a significant long-term trend

Water-Resources Investigations Report↗
USGS2003

Occurrence and distribution of dissolved trace elements in the surface waters of the Yakima River basin, Washington

The occurrence, distribution, and transport of dissolved (filtered-water) trace elements in the surface waters of the Yakima River Basin were assessed using data collected between 1999 and 2000 as part of the U.S. Geological Survey s National Water-Quality Assessment (NAWQA) Program. Samples were collected at 34 sites throughout the basin in August 1999, using a Lagrangian sampling design. From May 1999 through January 2000, samples also were collected weekly during the irrigation season and once per month during the nonirrigation season at three intensive fixed sites. Although the focus of this study was on 9 trace elements (aluminum, arsenic, barium, copper, iron, manganese, nickel, uranium, and zinc), 14 additional elements were analyzed in filtered water. Concentrations of most trace elements in filtered water generally were low and there were no exceedances of the U.S. Environmental Protection Agency (USEPA) freshwater aquatic-life water-quality criteria. The USEPA drinking-water standard for arsenic (10 µg/L) was exceeded in two samples that were collected under base-flow conditions during the nonirrigation season at Granger Drain. Over 40 percent of all filtered-water samples collected during this study exceeded the USEPA health advisory level of 2.0 µg/L for arsenic. Arsenic concentrations in agricultural drains were highest when the drains were primarily fed by shallow ground water, and concentrations in the Yakima River were highest when the river was fed primarily by agricultural return flow. The USEPA secondary maximum contaminant level for manganese (50 µg/L) was exceeded in three samples collected at Granger Drain during the nonirrigation season. Instantaneous arsenic loads calculated for August 1999 were similar to mean monthly loads determined in August 1989 at two intensive fixed sites located on the Yakima main stem. In August 1999, arsenic loads increased twofold between the Yakima River at river mile 72 above Satus and the Yakima River at Kiona at river mile 29.9. The dissolved arsenic loads for the Yakima River at Euclid Bridge at river mile 55 near Grandview and Yakima River at Kiona were within 13 percent of the August 1989 levels.

Water-Resources Investigations Report↗
USGS2002

Trend analysis of ground-water levels and spring discharge in the Yucca Mountain Region, Nevada and California, 1960-2000

Ground-water level and discharge data from 1960 to 2000 were analyzed for the Yucca Mountain region of southern Nevada and eastern California. Included were water-level data from 37 wells and a fissure (Devils Hole) and discharge data from five springs and from a flowing well. Data were evaluated for variability and for upward, downward, or cyclic trends with an emphasis on the period 1992-2000. Potential factors causing trends in water levels and discharge include ground-water withdrawal, infiltration of precipitation, earthquakes, evapotranspiration, barometric pressure, and earth tides. Statistically significant trends in ground-water levels or spring discharge from 1992 to 2000 were upward at 12 water-level sites and downward at 14 water-level sites and 1 spring-discharge site. In general, the magnitude of the change in water level from 1992 to 2000 was small (less than 2 feet), except where influenced by pumping or local effects such as possible equilibration from well construction or diversion of nearby surface water. Seasonal trends are superimposed on some of the long-term (1992-2000) trends in water levels and discharge. Factors causing seasonal trends include barometric pressure, evapotranspiration, and pumping. The magnitude of seasonal change in water level can vary from as little as 0.05 foot in regional aquifers to greater than 5 feet in monitoring wells near large supply wells in the Amargosa Farms area. Three major episodes of earthquake activity affected water levels in wells in the Yucca Mountain region between 1992 and 2000: the Landers/Little Skull Mountain, Northridge, and Hector Mine earthquakes. The Landers/Little Skull Mountain earthquakes, in June 1992, had the largest observed effect on water levels and on discharge during the study period. Monthly measurements of wells in the study network show that earthquakes affected water levels from a few tenths of a foot to 3.5 feet. In the Ash Meadows area, water levels remained relatively stable from 1992 to 2000, with some water levels showing small rising trends and some declining slightly. Possible reasons for water-level fluctuations at sites AD-6 (Tracer Well 3), AM-5 (Devils Hole Well), and AM-4 (Devils Hole) from 1960 to 2000 include climate change, local and regional ground-water withdrawals, and tectonic activity. In Jackass Flats, water levels from 1992 to 2000 in six wells adjacent to Fortymile Wash displayed either small upward trends or no upward or downward trend. Comparison of trends in water levels from 1983 to 2000 for these six wells shows good correlations between all wells and suggests a common mechanism controlling water levels in the area. Of the likely controls on the system--precipitation or pumping in Jackass Flats--precipitation appears to be the predominant factor controlling water levels near Fortymile Wash. Water levels in the heavily pumped Amargosa Farms area declined from about 10 to 30 feet from 1964 to 2000. Water-level declines accelerated beginning in the early 1990's as pumping rates increased substantially. Pumping in the Amargosa Farms area may affect water levels in some wells as far away as 5-14 miles. The water level at site DV-3 (Travertine Point 1 Well) and discharge at site DV-2 (Navel Spring), both in the Death Valley hydrographic area, had downward trends from 1992 to 2000. The cause of these downward trends may be linked to earthquakes, pumping in the Amargosa Farms area, or both.

Water-Resources Investigations Report↗
USGS2002

Trace elements and organic compounds in streambed sediment and fish tissue of coastal New England streams, 1998-99

Streambed sediment and fish tissue were collected at 14 river sites in eastern New England during low-flow conditions in 1998 and 1999 as part of the New England Coastal Basins (NECB) study of the U.S. Geological Survey National Water-Quality Assessment (NAWQA) Program. Sampling sites were selected over a range of urban settings. Population densities at selected sites ranged from 26 to 3,585 people per square mile, and urban land use ranged from 1 to 68 percent. The streambed sediment samples were analyzed for a total of 141 contaminants, including 45 trace elements, 32 organochlorine compounds, and 64 semi-volatile organic compounds. The fish tissue samples were analyzed for 22 trace elements and 28 organochlorine compounds. Concentrations of selected contaminants in both streambed sediment and fish tissue correlated more strongly with population density than with other watershed characteristics. Cadmium, copper, lead, mercury, zinc, total polycyclic aromatic hydrocarbons (PAHs), total polychlorinated biphenyls (PCBs), dichloro diphenyl trichloroethane and metabolites (DDTM), and total chlordane in streambed sediment all showed strong positive correlations with population density (rho = 0.71 to 0.85, p value = 0.005 to <0.001). Correlations between population density and selected contaminants in fish tissue were less significant than with streambed sediment (rho = 0.62 to 0.72, p value = 0.03 to 0.008). Organic carbon concentrations were correlated with concentrations of arsenic, selenium, total PAHs, total PCBs, and DDTM in streambed sediment. The relation between concentrations of contaminants in streambed sediment and fish tissue was stronger for organochlorine compounds (rho = 0.75 to 0.55, p = 0.005 to 0.065) than for trace elements (rho = 0.63 to 0.53, p = 0.029 to 0.069). The NECB study area had the highest median concentrations of lead, mercury, total PAHs, total PCBs, and DDTM in streambed sediment and the highest median concentration of PCBs in fish tissue compared to 45 other NAWQA study units across the Nation. Concentrations of many of these constituents in streambed sediment also were frequently above the consensus-based Sediment-Quality Guidelines for the protection of wildlife, suggesting they are a threat to the health of aquatic biota in New England.

Water-Resources Investigations Report↗
USGS2002

Response of the St. Croix River pools, Wisconsin and Minnesota, to various phosphorus-loading scenarios

The pools in the lower reach of the St. Croix National Scenic Riverway, Wisconsin and Minnesota, and the adjoining Lake Mallalieu, are eutrophic because of high phosphorus loading. To determine how changes in phosphorus loading would affect the trophic status of these pools, the water-quality model, BATHTUB, was used to simulate existing (1999) water quality and simulate the water quality with various phosphorus-loading scenarios. Water quality in the pools may respond differently during different flow regimes; therefore, sensitivity and scenario evaluations were performed not only for 1999, but also for a simulated period with relatively low flows throughout the basin (using flow data from 1988) and for a simulated period with relatively high flows throughout the basin (using flow data from 1996). On the basis of the BATHTUB simulations, linear increases in phosphorus loading should cause the following changes in water quality in each of the pools: linear increases in phosphorus concentrations, although at a smaller rate than the increase in loading; non-linear increases in chlorophyll a concentrations, with a smaller relative response with higher phosphorus loading; increase in the frequency of algal blooms, with a higher frequency of intense algal blooms; and slightly decreased water clarity. The response in water quality to changes in the phosphorus loading should be relatively similar regardless of the flow regime. Reducing phosphorus loading by about 50 percent would be necessary for the Lake St. Croix pools to be classified as mesotrophic with respect to phosphorus and chlorophyll a concentrations, whereas a larger reduction in phosphorus loading would be needed for Lake Mallalieu to be classified as mesotrophic. Even with these reductions, water clarity will remain poor because of the high non-algal turbidity and stained water in the pools.

Minnesota, Wisconsin↗
USGS2003

Occurrence and transport of cadmium, lead, and zinc in the Spokane River basin, Idaho and Washington, water years 1999-2001

A water-quality investigation of the Clark Fork-Pend Oreille and Spokane River Basins began in 1997 as part of the U.S. Geological Survey National Water-Quality Assessment Program. As part of the investigation, selected streams in the Spokane River Basin were sampled for trace metals during water years 1999–2001. These data, combined with data collected as part of a U.S. Environmental Protection Agency Remedial Investigation/ Feasibility Study, were used to assess the occurrence, loads, and transport of cadmium, lead, and zinc at 21 streamflow-gaging stations in the Spokane River Basin. Concentrations of dissolved and total cadmium, lead, and zinc varied widely both at and among stations. At most stations, dissolved cadmium and zinc composed most of the total concentrations; dissolved lead generally composed less than 10 percent of the total lead concentration. From the South Fork Coeur d’Alene River near Mullan downstream to the South Fork Coeur d’Alene River near Pinehurst, concentrations of trace metals increased 2 to 4 orders of magnitude. The mean flow-weighted concentrations of total cadmium, lead, and zinc near Pinehurst for water years 1999–2001 were 5.7, 80, and 810 micrograms per liter ( µg/L), respectively. On the Coeur d’Alene River near Harrison, downstream from the confluence of the metal-enriched South Fork and the relatively dilute North Fork Coeur d’Alene River, the mean flow-weighted concentrations of total cadmium, lead, and zinc were 1.6, 88, and 240 µg/L, respectively. Trace-metal concentrations were smaller in the Spokane River than in the Coeur d’Alene River because of dilution and retention in Coeur d’Alene Lake. The mean flowweighted concentrations of total cadmium, lead, and zinc in the Spokane River near Post Falls were 0.32, 3.1, and 71 µg/L, respectively. Regression models relating the mass transport, or load, of trace metals to changes in stream discharge and time were successful in simulating the variability in trace-metal concentrations and loads. The median coefficient of determination for the load models for the 21 stations was largest for total lead (92 percent) and smallest for dissolved and total cadmium (82 percent). Whereas most of the cadmium and zinc loads in the Spokane River Basin were derived from the South Fork Coeur d’Alene River, most of the lead load was derived from the Coeur d’Alene River downstream from the confluence of the North and South Forks. Major tributary sources of trace metals to the South Fork Coeur d’Alene River were Canyon Creek, Ninemile Creek, and Government Gulch. These three tributaries contributed about 3,000 pounds of cadmium, 23,000 pounds of lead, and 310,000 pounds of zinc annually to the South Fork Coeur d’Alene River. Erosion and transport of sediment-bound lead in the Coeur d’Alene River was the primary source of total lead, accounting for almost 400,000 pounds annually during water years 1999–2000. Ground-water discharge in the area of the Bunker Hill Superfund site was a major source of zinc in the South Fork Coeur d’Alene River, contributing more than 250,000 pounds per year. During water years 1999–2000, the average annual loads of cadmium, lead, and zinc transported from the Coeur d’Alene, St. Joe, and St. Maries Rivers to Coeur d’Alene Lake were 8,900, 500,000, and 1.4 million pounds, respectively. The Coeur d’Alene River accounted for more than 99 percent of the total load of each of these three metals entering the lake. About 4,600 pounds of cadmium, 44,000 pounds of lead, and 980,000 pounds of zinc were transported from Coeur d’Alene Lake into the Spokane River. Between the Spokane River near Post Falls, Idaho, and the Spokane River at Long Lake, Washington, there was an annual net loss of about 2,600, 20,000, and 250,000 pounds of cadmium, lead, and zinc, respectively. About 2,000 pounds of cadmium, 24,000 pounds of lead, and 730,000 pounds of zinc were transported annually downstream from Long Lake toward the Columbia River.

Idaho;Washington↗
USGS2003

Channel stability and water quality of the Alagnak River, southwestern Alaska

The Alagnak River, a National Wild River located in southwestern Alaska, drains an area of 3,600 square kilometers and is used for recreational and subsistence activities, primarily angling, camping, rafting, and hunting by visitors and seasonal residents, and for commercial guiding by several lodges. Increases in visitor use in the 1990s included an increase in the use of high-horsepower motorboats on the river, primarily for angling, and raised concerns regarding human impacts on water quality. Downstream from its confluence with the Nonvianuk River at river kilometer (RK) 93, the Alagnak River is formed in glacial drift and outwash with a single, low bedrock outcrop. Analysis of aerial photography from 1951, 1982, and 2001 shows that the river's multiple channels from RK 57 to 93 have been relatively stable. In contrast, long reaches of multiple channels from RK 35 to 57 changed substantially between 1951 and 1982, creating a new complex of channels. Downstream from RK 35, channel changes in the past 50 years consist largely of minor meander migration. Analysis of water samples collected during this study at RK 21, 46, and 93 and in the Alagnak and Nonvianuk Rivers at the outlets of the lakes that form their source shows that the Alagnak River is a nutrient-poor, calcium-bicarbonate water with low suspended-sediment concentrations. Water chemistry changes little over time or in a downstream direction. Weak patterns over time include high late May/early June concentrations of some nutrients, carbon, and iron. Weak patterns over distance include downstream increases in iron, manganese, and phosphorous. No pervasive human impacts on Alagnak River water chemistry were detected. Local effects that could be diluted within a kilometer downstream of the source were not detectable by this study. Data collected at three continuously recording wake gaging stations at RK 21, 46, and 93 showed that 1999-2000 motorboat use was heaviest in the lower reaches of the river, moderate in the middle reaches, and very light in the upper reaches. Maximum boat use was 137, 40, and 4 wakes per day at RK 21, 46, and 93, respectively. The mean height of the maximum wave generated in each wake was about 0.15 m (meters) at all three gaging stations. Bank erosion monitoring at 14 sites between RK 21 and 93 quantified erosion rates ranging from 0 to 1.1 m/yr (meters per year). Erodibility (based on grain-size analysis) increases in a downstream direction, as do measured erosion rates. Alagnak River banks are noncohesive and erode by grain-by-grain removal of sediment in an alternating pattern of water-driven erosion and gravitydriven erosion. Periodic surveys at bank erosion monitoring sites detected the development of a shallow underwater shelf formed by the action of wind waves and boat wakes at several sites. This shelf contains sediment eroded from the bank and redeposited adjacent to the bank; the shelf reformed as water levels changed but maintained the same wave-generated form throughout much of the season. Measurements of bank erosion processes, particularly the development of a wave-generated shelf, and visual observations suggest that boat wakes increase bank erosion rates, especially at high, exposed banks. Analysis of aerial photography and other assessments of bank erosion processes indicate that this increase in erosion rates has not altered the mechanisms of channel change, which in the past 50 years have included complex, compound channel changes and meander migration.

Water-Resources Investigations Report↗
USGS2002

Flow-system analysis of the Madison and Minnelusa aquifers in the Rapid City area, South Dakota — Conceptual model

The conceptual model of the Madison and Minnelusa aquifers in the Rapid City area synthesizes the physical geography, hydraulic properties, and ground-water flow components of these important aquifers. The Madison hydrogeologic unit includes the karstic Madison aquifer, which is defined as the upper, more permeable 100 to 200 ft of the Madison Limestone, and the Madison confining unit, which consists of the lower, less permeable part of the Madison Limestone and the Englewood Formation. Overlying the Madison hydrogeologic unit is the Minnelusa hydrogeologic unit, which includes the Minnelusa aquifer in the upper, more permeable 200 to 300 ft and the Minnelusa confining unit in the lower, less permeable part. The Madison and Minnelusa hydrogeologic units outcrop in the study area on the eastern flank of the Black Hills where recharge occurs from streamflow losses and areal recharge. The conceptual model describes streamflow recharge, areal recharge, ground-water flow, storage in aquifers and confining units, unsaturated areas, leakage between aquifers, discharge from artesian springs, and regional outflow. Effective transmissivities estimated for the Madison aquifer range from 500 to 20,000 ft 2 /d and for the Minnelusa aquifer from 500 to 10,000 ft 2 /d. Localized anisotropic transmissivity in the Madison aquifer has tensor ratios as high as 45:1. Vertical hydraulic conductivities for the Minnelusa confining unit determined from aquifer tests range from 1.3x10 -3 to 3.0x10 -1 ft/d. The confined storage coefficient of the Madison and Minnelusa hydrogeologic units was estimated as 3x10 -4 ft/d. Specific yield was estimated as 0.09 for the Madison and Minnelusa aquifers and 0.03 for the Madison and Minnelusa confining units. Potentiometric surfaces for the Madison and Minnelusa aquifers have a general easterly gradient of about 70 ft/mi with local variations. Temporal change in hydraulic head in the Madison and Minnelusa aquifers ranged from about 5 to 95 ft in water years 1988-97. The unconfined areas were estimated at about 53 and 36 mi 2 for the Madison and Minnelusa hydrogeologic units, respectively, in contrast to an aquifer analysis area of 629 mi 2 . Dye-tracer tests, stable isotopes, and hydrogeologic features were analyzed conjunctively to estimate generalized ground-water flowpaths in the Madison aquifer and their influences on the Minnelusa aquifer. The western Rapid City area between Boxelder Creek and Spring Creek was characterized as having undergone extensive tectonic activity, greater brecciation in the Minnelusa Formation, large transmissivities, generally upward hydraulic gradients from the Madison aquifer to the Minnelusa aquifer, many karst springs, and converging flowpaths. Water-budget analysis included: (1) a dry-period budget for declining water levels; October 1, 1987, to March 31, 1993; (2) a wet-period budget for rising water levels, April 1, 1993, to September 30, 1997; and (3) a full 10-year period budget for water years 1988-97. By simultaneously balancing these water budgets, initial estimates of recharge, discharge, change in storage, and hydraulic properties were refined. Inflow rates for the 10-year budget included streamflow recharge of about 45 ft 3 /s or 61 percent of the total budget and areal recharge of 22 ft 3 /s or 30 percent. Streamflow recharge to the Madison hydrogeologic unit was about 86 percent of the total streamflow recharge. Outflow for the 10-year budget included springflow of 31 ft 3 /s or 42 percent of the total budget, water use of about 10 ft 3 /s or 14 percent, and regional outflow of 22 ft 3 /s or 30 percent. Ground-water storage increased 9 ft 3 /s during the 10-year period, and net ground-water movement from the Madison to Minnelusa hydrogeologic unit was about 8 ft 3 /s.

South Dakota↗