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Summary of ground-water and surface-water data for city of Pensacola and Escambia County, Florida

Hydrologic, geologic, and water-quality data collected in Escambia County, Florida, October 1962 through September 1980 are presented. The data were collected by the U.S. Geological Survey as part of a cooperative investigation with the city of Pensacola and Escambia County to provide information on the quality and quantity of water available from the sand-and-gravel aquifer and selected surface-water sites in Escambia County. Ground-water data include records of 440 wells, chemical and physical analyses of water quality for 325 wells, 6 long-term hydrographs, and 19 lithologic logs. Surface-water data include streamflow measurements and analyses of water collected at 9 sites. Maps of the county show the locations of the data-collection sites. (USGS)

Open-File Report↗

Hydrogeology of aquifers within the Fairport-Lyons channel system and adjacent areas in Wayne, Ontario, and Seneca Counties, New York

A hydrogeologic investigation was undertaken by the U.S. Geological Survey, in cooperation with the New York State Department of Environmental Conservation, within the areas shown in the Macedon, Palmyra, Newark, and Lyons 7.5-minute quadrangle maps that include parts of Wayne, Ontario, and Seneca Counties in New York. The most productive zone of aquifers within the study area is associated with the Fairport-Lyons glacial-stream channel (hereinafter referred to as the “Fairport-Lyons channel”) in southern Wayne County and adjacent areas. The Fairport-Lyons channel is a west-east-oriented bedrock channel that once served as the outlet for glacial Lake Dawson, which occupied the Genesee Valley near Rochester during the Pleistocene. The Fairport-Lyons channel and intersecting subsidiary channels are hereinafter referred to as the “Fairport-Lyons channel system.” Glacial meltwater eroded this shallow channel network into the underlying bedrock, and the channels subsequently filled with interlayered glaciofluvial sand and gravel and fine-grained lacustrine deposits. These sand and gravel deposits provide the only large supplies of groundwater in Wayne County under unconfined and confined conditions and serve a population of over 20,000 through a combination of domestic and municipal water supply wells. The largest reported well yield, 1,200 gallons per minute, is from an industrial supply well near Newark, N.Y. Much of the sand and gravel within the Fairport-Lyons channel system is generally thinly saturated; however, in three areas—near Macedon, Newark, and Lyons, N.Y.—the saturated thickness of the aquifer is sufficient to support groundwater yields adequate for municipal and industrial use, in part because of induced infiltration from the Erie Canal.

New York↗

Archive of digitized analog boomer and minisparker seismic reflection data collected from the Alabama-Mississippi-Louisiana Shelf during cruises onboard the R/V Carancahua and R/V Gyre, April and July, 1981

In April and July of 1981, the U.S. Geological Survey (USGS) conducted geophysical surveys to investigate the shallow geologic framework of the Alabama-Mississippi-Louisiana Shelf in the northern Gulf of Mexico. Work was conducted onboard the Texas A&M University R/V Carancahua and the R/V Gyre to develop a geologic understanding of the study area and to locate potential hazards related to offshore oil and gas production. While the R/V Carancahua only collected boomer data, the R/V Gyre used a 400-Joule minisparker, 3.5-kilohertz (kHz) subbottom profiler, 12-kHz precision depth recorder, and two air guns. The authors selected the minisparker data set because, unlike with the boomer data, it provided the most complete record. This report is part of a series to digitally archive the legacy analog data collected from the Mississippi-Alabama SHelf (MASH). The MASH data rescue project is a cooperative effort by the USGS and the Minerals Management Service (MMS). This report serves as an archive of high-resolution scanned Tagged Image File Format (TIFF) and Graphics Interchange Format (GIF) images of the original boomer and minisparker paper records, navigation files, trackline maps, Geographic Information System (GIS) files, cruise logs, and formal Federal Geographic Data Committee (FGDC) metadata.

Alabama, Louisiana, Mississippi↗

Hydrologic data for urban studies in the Houston, Texas, metropolitan area, 1982

Hydrologic investigations of urban watersheds in Texas were begun by the U.S. Geological Survey in 1954. Studies are now in progress in Austin, and Houston. Studies have been completed in the Dallas-Fort Worth and San Antonio areas. The U.S. Geological Survey, in cooperation with the city of Houston, began studies in the Houston metropolitan area in 1964. The program was expanded in 1968 to include collection of water-quality data. The objectives of the Houston urban-hydrology study are as follows: To determine, on the basis of historical data and hydrologic analyses, the magnitude and frequency of flood peaks and flood volumes. To determine the effect of urban development on flood peaks and volumes. To ascertain the variation in water quality for different flow conditions and different seasons. This report, the nineteenth in a series of reports to be published annually, is primarily applicable to objective 2. The report presents hydrologic data collected in the Houston urban area for the 1982 water year (October 1, 1981 to September 30, 1982). A report by Johnson and Sayre (1973) utilized records collected from 1965 to 1969 to study the effects of urbanization on floods in the Houston area. The report also summarizes various basin parameters. A report by Waddell, Massey, and Jennings (1979) presents data on runoff from the Houston area and computed concentrations and loads of selected water-quality constituents discharged to Galveston Bay. The study utilized a variation of the "STORM" model developed by the Hydrologic Engineering Center of the U.S. Army Corps of Engineers. A report prepared by Li scum and Massey (1980) presents a technique for estimating the magnitude and frequency of floods in the Houston area from drainage areas, bank-full conveyance, and percentage of urban development. A definition of terms related to streamflow, water quality, and other hydrologic data, as used in this report, are defined in "U.S. Geological Survey, Water-resources data for Texas, water year 1982, volume 2." To facilitate the publication and distribution of this report some material has been included that does not conform to the formal publications standards of the U.S. Geological Survey.

Texas↗

Hydrologic data for urban studies in the Houston, Texas, metropolitan area, 1981

Hydro! oqic investigations of urban watersheds in Texas were begun by the U.S. Geological Survey in 1954. Studies are now in progress in Austin, and Houston. Studies have been completed in the Dallas-Fort Worth and San Antonio areas. The U.S. Geological Survey, in cooperation with the city of Houston, began studies in the Houston metropolitan area in 1964. The program was expanded in 1968 to include collection of water-quality data. The objectives of the Houston urban-hydrology study are as follows: To determine, on the basis of historical data and hydro!ogic analyses, the magnitude and frequency of flood peaks and flood volumes. To determine the effect of urban development on flood peaks and volumes. To ascertain the variation in water quality for different flow conditions and different seasons. This report, the eighteenth in a series of reports to be published annually, is primarily applicable to objective 2. The report presents hydro!ogic data collected in the Houston urban area for the 1981 water year (October 1, 1980 to September 30, 1981).

Texas↗

Preliminary hydrogeologic assessment near the boundary of the Antelope Valley and El Mirage Valley groundwater basins, California

The increasing demands on groundwater for water supply in desert areas in California and the western United States have resulted in the need to better understand groundwater sources, availability, and sustainability. This is true for a 650-square-mile area that encompasses the Antelope Valley, El Mirage Valley, and Upper Mojave River Valley groundwater basins, about 50 miles northeast of Los Angeles, California, in the western part of the Mojave Desert. These basins have been adjudicated to ensure that groundwater rights are allocated according to legal judgments. In an effort to assess if the boundary between the Antelope Valley and El Mirage Valley groundwater basins could be better defined, the U.S. Geological Survey began a cooperative study in 2014 with the Mojave Water Agency to better understand the hydrogeology in the area and investigate potential controls on groundwater flow and availability, including basement topography. Recharge is sporadic and primarily from small ephemeral washes and streams that originate in the San Gabriel Mountains to the south; estimates range from about 400 to 1,940 acre-feet per year. Lateral underflow from adjacent basins has been considered minor in previous studies; underflow from the Antelope Valley to the El Mirage Valley groundwater basin has been estimated to be between 100 and 1,900 acre-feet per year. Groundwater discharge is primarily from pumping, mostly by municipal supply wells. Between October 2013 and September 2014, the municipal pumpage in the Antelope Valley and El Mirage Valley groundwater basins was reported to be about 800 and 2,080 acre-feet, respectively. This study was motivated by the results from a previously completed regional gravity study, which suggested a northeast-trending subsurface basement ridge and saddle approximately 3.5 miles west of the boundary between the Antelope Valley and El Mirage Valley groundwater basins that might influence groundwater flow. To better define potential basement structures that could affect groundwater flow between the groundwater basins in the study area, gravity data were collected using more closely spaced measurements in September 2014. Groundwater-level data was gathered and collected from March 2014 through March 2015 to determine depth to water and direction of groundwater flow. The gravity and groundwater-level data showed that the saturated thickness of the alluvium was about 2,000 feet thick to the east and about 130 feet thick above the northward-trending basement ridge near Llano, California. Although it was uncertain whether the basement ridge affects the groundwater system, a potential barrier to groundwater flow could be created if the water table fell below the altitude of the basement ridge, effectively causing the area to the west of the basement ridge to become hydraulically isolated from the area to the east. In addition, the direction of regional-groundwater flow likely will be influenced by future changes in the number and distribution of pumping wells and the thickness of the saturated alluvium from which water is withdrawn. Three-dimensional animations were created to help visualize the relation between the basins’ basement topography and the groundwater system in the area. Further studies that could help to more accurately define the basins and evaluate the groundwater-flow system include exploratory drilling of multi-depth monitoring wells; collection of depth-dependent water-quality samples; and linking together existing, but separate, groundwater-flow models from the Antelope Valley and El Mirage Valley groundwater basins into a single, calibrated groundwater-flow model.

California↗

Characterization of groundwater resources near the southeastern part of Puget Sound, Washington

More than 1 million people live within the active model area (AMA) in the southeastern part of the lowlands surrounding Puget Sound, or Puget Lowland, Washington, and groundwater is the source for approximately one-half of their public, domestic, and irrigation water demands. The 887-square-mile AMA, located in King and Pierce Counties, represents the area of analysis for the conceptual hydrogeologic framework and numerical groundwater-flow models within the study area and includes the Puyallup River and Chambers-Clover Creek watersheds. To assess the potential hydrologic and anthropogenic impacts to groundwater and the connected surface-water resources, conceptual and numerical groundwater-flow models of groundwater flow were developed by the U.S. Geological Survey Washington Water Science Center in close cooperation with 18 water-resource agencies and stakeholders. This multichapter volume documents the development of the conceptual and numerical groundwater-flow models of groundwater flow. Chapters A, B, and C provide an overall introduction to the multichapter volume (Chapter A), the conceptual hydrogeologic framework (Chapter B), and the groundwater budget (Chapter C). Chapters D and E describe numerical groundwater-flow model construction and calibration (Chapter D) and the numerical groundwater-flow model results (Chapter E). Collectively, these reports present a characterization and simulation tool for groundwater resources near the southeastern part of Puget Sound, Washington.

Scientific Investigations Report↗

Hydrologic data for urban studies in the Houston metropolitan area, Texas, 1983

Hydro!ogic investigations of urban watersheds in Texas were begun by the U.S. Geological Survey in 1954. Studies are now in progress in the Austin and Houston areas, and have been completed in the Dallas-Fort Worth and San Antonio areas. The U.S. Geological Survey, in cooperation with the city of Houston, began studies in the Houston metropolitan area in 1964. The program was expanded in 1968 to include collection of water-quality data. The objectives of the Houston urban-hydrology study are as follows: To determine, on the basis of historical data and hydrologic analyses, the magnitude and frequency of flood peaks and flood volumes. To determine the effect of urban development on flood peaks and volumes. To ascertain the variation in water quality for different flow conditions and different seasons. This report, the twentieth in a series of reports to be published annually, is primarily applicable to objective No. 2. The report presents hydrologic data collected in the Houston urban area for the 1983 water year (October 1, 1982, to September 30, 1983). A report by Johnson and Sayre (1973) utilized records collected from 1965 to 1969 to study the effects of urbanization on floods in the Houston area. That report also summarized various basin parameters. A report by Waddell, Massey, and Jennings (1979) presented data on runoff from the Houston area and computed concentrations and loads of selected water-quality constituents discharged to Galveston Bay. The study utilized a variation of the "STORM" model developed by the Hydrologic Engineering Center of the U.S. Army Corps of Engineers. A report prepared by Li scum and Massey (1980) presented a technique for estimating the magnitude and frequency of floods in the Houston area from drainage areas, bank-full conveyance, and percentage )f urban development. A definition of terms related to streamflow, water quality, and other hydrologic data, as used in this report, are defined in " U.S. Geological Survey, Water-resources data for Texas, water year 1983, volume 2."

Texas↗

Map showing general availability of ground water in the Salina quadrangle, Utah

The general availability of ground water was determined from well records collected by the U.S. Geological Survey and cooperating State, local, and Federal agencies. Data are for aquifers that in most places are less than 1,000 feet below the land surface. In areas of few or no wells, potential well yields are inferred from geologic data. Special investigations are needed to determine specific factors such as depths and sustained yields of aquifers, water levels, and suitability of water for use in any given area. More detailed information about principal aquifers for specific parts of the map area are obtainable from the district office of the Water Resources Division, U.S. Geological Survey, Salt Lake City, Utah.

Utah↗

Hydrologic data for urban studies in the Houston metropolitan area, Texas, 1984

Hydrologic investigations of urban watersheds in Texas were begun by the U.S. Geological Survey in 1954. Studies are now in progress in the Austin and Houston areas, and have been completed in the Dallas-Fort Worth and San Antonio areas. The U.S. Geological Survey, in cooperation with the city of Houston, began studies in the Houston metropolitan area in 1964. The program was expanded in 1968 to include collection of water-quality data. The objectives of the Houston urban-hydrology study are as follows: To determine, on the basis of historical data and hydrologic analyses, the magnitude and frequency of flood peaks and flood volumes; To determine the effect of urban development on flood peaks and volumes; and To ascertain the variation in water quality for different flow conditions and different seasons. This report, the twenty-first and last scheduled in a series of reports published annually, is primarily applicable to objective 2. The report presents hydrologic data collected in the Houston urban area for the 1984 water year (October 1, 1983 to September 30, 1984). A report by Johnson and Sayre (1973) utilized records collected from 1965 to 1969 to study the effects of urbanization on floods in the Houston area. That report also summarized various basin parameters. A report by Waddell, Massey, and Jennings (1979) presented data on runoff from the Houston area and computed concentrations and loads of selected water-quality constituents discharged to Galveston Bay. The study utilized a variation of the "STORM" model developed by the Hydrologic Engineering Center of the U.S. Army Corps of Engineers. A report prepared by Liscum and Massey (1980) presented a technique for estimating the magnitude and frequency of floods in the Houston area from drainage areas, bank-full conveyance, and percentage of urban development. A definition of terms related to streamflow, water quality, and other hydrologic data, as used in this report, are defined in "U.S. Geological Survey, Water-resources data for Texas, water year 1984, volume 2."

Texas↗

Hydrogeologic characterization of the Yucaipa groundwater subbasin

Introduction Water management in the Santa Ana River watershed in San Bernardino and Riverside Counties in southern California (fig. A1) is complex with various water purveyors navigating geographic, geologic, hydrologic, and political challenges to provide a reliable water supply to stakeholders. As the population has increased throughout southern California, so has the demand for water. The Yucaipa groundwater subbasin (hereafter referred to as “Yucaipa subbasin”), one of nine groundwater subbasins in what the California Department of Water Resources (DWR) refers to as the Upper Santa Ana Valley groundwater basin (California Department of Water Resources, 2016; fig. A1; the DWR naming convention is used within this report), is no exception; steady population growth since the 1940s and changes in water use have forced local water purveyors to regularly adapt their water infrastructure. Water demands within the Yucaipa subbasin have historically been supplied by groundwater, but water imported via the California State Water Project has augmented the total water supply through direct use and through anthropogenic recharge at the Wilson Creek and Oak Glen Creek spreading basins since 2002. Overall demand for groundwater continues to rise, and local water managers are concerned that despite the influx of imported water, groundwater levels may decline to a point where producing water will be uneconomical, severely limiting the ability of local agencies to meet water-supply demand. To better understand the hydrogeology and water resources in the Yucaipa subbasin, the U.S. Geological Survey (USGS) initiated a study in cooperation with the San Bernardino Valley Municipal Water District (SBVMWD) to characterize and model the hydrologic system of the Yucaipa subbasin and the surrounding Yucaipa Valley watershed (YVW; fig. A2). To gain this comprehensive understanding, a three-dimensional (3D) hydrogeologic framework model (HFM; Cromwell and Matti, 2022) was constructed to quantify the structure and extent of hydrogeologic units in the YVW; the hydrologic system was conceptualized and quantified (described in chapter A); and the Yucaipa Integrated Hydrological Model (YIHM; described in chapter B ) was developed to simulate the integrated surface-water and aquifer systems, including natural and anthropogenic recharge and discharge throughout the study area during 1947–2014.

Scientific Investigations Report↗

Bathymetry and capacity of Chambers Lake, Chester County, Pennsylvania

Introduction Chambers Lake is a manmade reservoir on Birch Run, a tributary to West Branch Brandywine Creek in Chester County, Pennsylvania. The lake was created in 1994 after the completion of Multi-Purpose Dam PA-436F (Hibernia Dam), which was built under the Watershed Protection & Flood Control Prevention Act (U.S. Soil Conservation Service, 1991). Hibernia dam is 1,700 feet upstream from the confluence of Birch Run with West Branch Brandywine Creek. The primary objectives for Hibernia Dam were to provide (1) flood control, (2) a supplemental source of water supply for the greater City of Coatesville public water system, and (3) recreational opportunities. The drainage basin of Chambers Lake encompasses approximately 4.5 square miles, and the lake covers a surface area of about 95 acres at normal pool, which is at an elevation of 579.2 feet above the North American Vertical Datum of 1988 (NAVD 88) [580.0 feet above the National Geodetic Vertical Datum of 1929 (NGVD 29)]. The crest of the auxiliary spillway of the dam is 586.6 feet above NAVD 88. The elevation of the auxiliary spillway is important to this investigation because this elevation defines the flood storage capacity of Chambers Lake. Water levels exceeding this elevation are routed through the auxiliary spillway and flow through adjoining woodland to Birch Run. The U.S. Geological Survey (USGS), in cooperation with Chester County Water Resources Authority (CCWRA) and the County of Chester, surveyed the bathymetry and selected above-water features of Chambers Lake in September 2014. The purpose of the survey was to develop an accurate representation of the surface of the bottom of Chambers Lake and to determine the stage area and reservoir-storage capacity relation as of September 2014. CCWRA is responsible for operation of the dam and water-supply reservoir. Since construction, CCWRA has used a stage–storage capacity relation developed from the original survey conducted in the 1990s to estimate the volume of water available for water supply and the available flood storage. The bathymetric mapping effort was initiated due to interest in potential changes in current (2014) storage capacity when compared to the stage–storage capacity relation developed during design. The generated bathymetric surface may serve as a baseline to which temporal changes in storage capacity, owing to sedimentation and other factors, can be compared. In addition, these data will improve the overall accuracy of the stage–storage capacity table that CCWRA uses for reservoir and flood management operations. This report describes the methods used to create a bathymetric map of Chambers Lake for the computation of reservoir storage capacity as of September 2014. The product is a bathymetric map and a table showing the storage capacity of the reservoir at 2-foot increments from minimum usable elevation up to full capacity at the crest of the auxiliary spillway.

Pennsylvania↗

Data-collection methods, quality-assurance data, and site considerations for total dissolved gas monitoring, lower Columbia River, Oregon and Washington, 2000

Excessive total dissolved gas pressure can cause gas-bubble trauma in fish downstream from dams on the Columbia River. In cooperation with the U.S. Army Corps of Engineers, the U.S. Geological Survey collected data on total dissolved gas pressure, barometric pressure, water temperature, and probe depth at eight stations on the lower Columbia River from the John Day forebay (river mile 215.6) to Camas (river mile 121.7) in water year 2000 (October 1, 1999, to September 30, 2000). These data are in the databases of the U.S. Geological Survey and the U.S. Army Corps of Engineers. Methods of data collection, review, and processing, and quality-assurance data are presented in this report.

Oregon, Washington↗

Geographic Information Systems Methods for Determining Drainage-Basin Areas, Stream-Buffered Areas, Stream Length, and Land Uses for the Neosho and Spring Rivers in Northeastern Oklahoma

Geographic Information Systems have many uses, one of which includes the reproducible computation of environmental characteristics that can be used to categorize hydrologic features. The Oklahoma Department of Wildlife Conservation and the Oklahoma Department of Environmental Quality are investigating Geographic Information Systems techniques to determine partial drainage-basin areas, stream-buffer areas, stream length, and land uses (drainage basin and stream characteristics) in northeastern Oklahoma. The U.S Geological Survey, in cooperation with Oklahoma Department of Wildlife Conservation and the Oklahoma Department of Environmental Quality, documented the methods used to determine drainage-basin and stream characteristics for the Neosho and Spring Rivers above Grand Lake Of the Cherokees in northeastern Oklahoma and calculated the characteristics. The drainage basin and stream characteristics can be used by the Oklahoma Department of Wildlife Conservation and the Oklahoma Department of Environmental Quality to aid in natural-resource assessments.

Scientific Investigations Report↗

Ground-water resources of Tinian, Commonwealth of the Northern Mariana Islands

Tinian, which lies in the western Pacific Ocean at latitude 15°N and longitude 145°W (fig. 1), is the second largest island (39.2 mi 2 ) in the Commonwealth of the Northern Mariana Islands (CNMI). Fresh ground water is obtained from shallow wells that tap the surface of a freshwater lends found in an aquifer composed mainly of coralline limestone. The main water-supply well withdraws water with a chloride concentration ranging from 160 to 220 mg/L. Current (1999) pumping rates adequately supply the island residents but future demand are expected to be higher.. To better understand the ground-water resources of the island and to learn more about the hydrology of oceanic islands, the U.S. Geological Survey (USGS) entered into a cooperative study with the Municipality of Tinian. The objective of the study, conducted between 1990 and 1997, was to assess the ground-water resources of the is;land. This report presents some of the results of the study including a description of the island's geology and geography, the current land use, the water-production system, the thickness and arcal extent of the freshwater lens, the water-table configuration and directions of ground-water flow. The report also discusses the relation of the changes in water-table elevation to daily and seasonal changes in ocean level.

Tinian Island↗

Snake River fall Chinook salmon life history investigations, 1/1/2012 - 12/31/2012: Annual report 2002-032-00

Executive Summary a. Fish Population RM&E This annual report describes the data collected and analyses conducted during calendar years 2012-2013 by staff of project 20023200. The USGS contributed only to the predation research and reservoir invertebrate work described in this report and the presentation of their results is consistent with USGS policy guidelines. The USGS is not responsible for the content provided by other contributing authors. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government. The main goal of this project is to better understand juvenile Snake River fall Chinook salmon life history diversity and the factors that influence it. This is called for in RPA 55.4 “Investigate key characteristics of Snake River fall Chinook salmon early life history.” We 3 investigated the importance of estuary entry and rearing to various Snake River fall Chinook salmon life histories. Otoliths were used to examine differences in estuary use between subyearlings and yearlings, and to determine natal habitats, rearing habitats, and overwintering habitat for returning adults. Estuary growth was best explained by estuary residence time and natal location. b. Predation and Invasive Species Management RM&E We investigated the extent of smallmouth bass predation on juvenile fall Chinook salmon in Lower Granite Reservoir as called for in the Fish and Wildlife Program, “The federal action agencies should work cooperatively with NOAA Fisheries, states, tribes, and the Council to review, evaluate, develop, and implement strategies to reduce non-native piscivorous predation on salmon and steelhead, especially by smallmouth bass, channel catfish, and walleye” (Page 52). Smallmouth bass stomach contents were collected and analyzed for the presence of juvenile salmon. Smallmouth bass abundance was estimated with mark-recapture techniques, and salmon consumption by bass was expanded based on bass abundance to determine the annual loss of juvenile fall Chinook salmon for the study period and area. The estimated loss of juvenile fall Chinook salmon to predation in Lower Granite Reservoir exceeded 109,000 fish in 2012. This information could be used to adaptively formulate better hatchery release strategies to reduce the effects of predation. Obtaining better estimates of smallmouth bass abundance and distribution in future years would reduce the uncertainty of estimates. This study will be completed by 2017. We also examined the effects of various field temperature scenarios resulting from summer flow augmentation on juvenile fall Chinook salmon susceptibility to smallmouth bass predation in laboratory trials. Predation susceptibility of juvenile salmon acclimated at cool temperatures (10°C) was highest when exposed to predators at 24°C. These results indicate that predation susceptibility may be higher when a relatively large temperature difference exists between the Clearwater and Snake rivers; that is, when cool water flow augmentation occurs in summer. Finally, we examined the role of different invasive invertebrates in lower Snake River reservoir food webs that are food, or competitors for food, for juvenile fall Chinook salmon. The Siberian prawn, a relatively new invader, is relatively abundant but its role on the food web is largely unexplored. Prawns are successfully reproducing and their diet is 81% Neomysis (an invasive opossum shrimp) which is heavily used at times by juvenile salmon for food. Neomysis has become very abundant in lower Snake River reservoirs in recent years and may be a profitable food item for many fish species.

Oregon, Washington↗

Factors affecting reservoir and stream-water quality in the Cambridge, Massachusetts, drinking-water source area and implications for source-water protection

This report presents the results of a study conducted by the U.S. Geological Survey, in cooperation with the city of Cambridge, Massachusetts, Water Department, to assess reservoir and tributary-stream quality in the Cambridge drinking-water source area, and to use the information gained to help guide the design of a comprehensive water-quality monitoring program for the source area. Assessments of the quality and trophic state of the three primary storage reservoirs, Hobbs Brook Reservoir, Stony Brook Reservoir, and Fresh Pond, were conducted (September 1997-November 1998) to provide baseline information on the state of these resources and to determine the vulnerability of the reservoirs to increased loads of nutrients and other contaminants. The effects of land use, land cover, and other drainage-basin characteristics on sources, transport, and fate of fecal-indicator bacteria, highway deicing chemicals, nutrients, selected metals, and naturally occurring organic compounds in 11 subbasins that contribute water to the reservoirs also was investigated, and the data used to select sampling stations for incorporation into a water-quality monitoring network for the source area. All three reservoirs exhibited thermal and chemical stratification, despite artificial mixing by air hoses in Stony Brook Reservoir and Fresh Pond. The stratification produced anoxic or hypoxic conditions in the deepest parts of the reservoirs and these conditions resulted in the release of ammonia nitrogen orthophosphate phosphorus, and dissolved iron and manganese from the reservoir bed sediments. Concentrations of sodium and chloride in the reservoirs usually were higher than the amounts recommended by the U.S. Environmental Protection agency for drinking-water sources (20 milligrams per liter for sodium and 250 milligrams per liter for chloride). Maximum measured sodium concentrations were highest in Hobbs Brook Reservoir (113 milligrams per liter), intermediate in Stony Brook Reservoir (62 milligrams per liter), and lowest in Fresh Pond (54 milligrams per liter). Bed sediments in Hobbs Brook and Stony Brook Reservoirs were enriched in iron, manganese, and arsenic relative to those in the impounded lower Charles River in Boston, Massachusetts. Trophic state indices, calculated for each reservoir based on nutrient concentrations, water-column transparency, and phytoplankton abundances, indicated that the upper and middle basins of Hobbs Brook Reservoir were moderately to highly productive and likely to produce algal blooms; the lower basin of Hobbs Brook Reservoir and Stony Brook Reservoir were similar and intermediate in productivity, and Fresh Pond was relatively unproductive and unlikely to produce algal blooms. This pattern is likely due to sedimentation of organic and inorganic particles in the three basins of Hobbs Brook Reservoir and in Stony Brook Reservoir. Molar ratios of nitrogen to phosphorus ranged from 55 in Stony Brook Reservoir to 120 in Hobbs Brook Reservoir, indicating that phytoplankton algae in these water bodies may be phosphorus limited and therefore sensitive to small increases in phosphorus loading from the drainage basin. Nitrogen loads were found to be less important than phosphorus to the trophic condition of the reservoirs. Hobbs Brook and Stony Brook, the two principle streams draining the Cambridge drinking-water source area, differed in their relative contributions to many of the estimated constituent loads. The estimated load of fecal coliform bacteria was more than seven times larger for the mainly residential Stony Brook subbasin upstream from Kendal Green, Mass., than it was for the more commercial and industrial Hobbs Brook subbasin, though the drainage areas of the two subbasins differ only by about 20 percent. The State standard for fecal coliform bacteria in streams in the Cambridge drinking-water source area (20 colony forming units per 100 milliliters) was exceeded at all sampling stations. Estimated s

Massachusetts↗

Hydrogeology of Webb County, Texas

Introduction Webb County, in semiarid South Texas on the U.S.-Mexico border, is a region confronted by increasing stresses on natural resources. Laredo (fig. 1), the largest city in Webb County (population 193,000 in 2000), was one of the 10 fastest-growing metropolitan areas in the country during 1990-2000 (Perry and Mackun, 2001). Commercial and industrial activities have expanded throughout the region to support the maquiladora industry (manufacturing plants in Mexico) along the border and other growth as a result of the passage of the North American Free Trade Agreement. The Rio Grande currently (2002) is the primary source of public water supply for Laredo and other cities along the border in Webb County (fig. 1). Other cities, such as Bruni and Mirando City in the southeastern part of the county, rely on ground-water supplies to meet municipal demands. Increased water demand associated with development and population growth in the region has increased the need for the City of Laredo and Webb County to evaluate alternative water sources to meet future demand. Possible options include (1) supplementing the surface-water supply with ground water, and (2) applying artificial storage and recovery (ASR) technology to recharge local aquifers. These options raise issues regarding the hydraulic capability of the aquifers to store economically substantial quantities of water, current or potential uses of the resource, and possible effects on the quality of water resulting from mixing ground water with alternative source waters. To address some of these issues, the U.S. Geological Survey (USGS), in cooperation with the City of Laredo, began a study in 1996 to assess the ground-water resources of Webb County. A hydrogeologic study was conducted to review and analyze available information on the hydrogeologic units (aquifers and confining units) in Webb County, to locate available wells in the region with water-level and water-quality information from the aquifers, and to analyze the hydraulic properties of the aquifers. The purpose of this report is to document the findings of the study. The information is organized by hydrogeologic unit and presented on this and six other sheets.

Texas↗