SEARCH · Geology Reports
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.
This fact sheet presents a brief overview of groundwater and surface-water resources in Cameron Parish, Louisiana. Information on the availability, use, and quality of water from groundwater and surface-water sources in the parish is discussed. Previously published reports and data stored in the U.S. Geological Survey’s National Water Information System ( http://waterdata.usgs.gov/nwis ) are the primary sources of this information.
Maine StreamStats is a tool that any user with Internet access can use to delineate a basin on the fly and estimate a wide variety of streamflow statistics for ungaged sites on rivers and streams in Maine. Estimates are based on regression equations or are from data from similar gaged locations on the stream. Maine StreamStats is based on a national StreamStats application that can be used for streamflow estimates in many other states across the country. Reports referenced in this fact sheet present the regression equations used to estimate the flow statistics, describe the errors associated with the estimates, and describe the methods used to develop the equations and to measure the basin characteristics used in the equations. Limitations of the methods are also described in the reports; for example, all of the equations are appropriate only for ungaged, unregulated, rural streams in Maine.
Sussex County, Delaware, occupies a 938-square-mile area of low relief near sea level in the Atlantic Coastal Plain. The county is bounded on the east by the Delaware Bay and the Atlantic Ocean, including a barrier-island system, and inland bays that provide habitat for valuable living resources. Eastern Sussex County is an area of rapid population growth with a long-established beach-resort community, where land elevation is a key factor in determining areas that are appropriate for development. Of concern to State and local planners are evacuation routes inland to escape flooding from severe coastal storms, as most major transportation routes traverse areas of low elevation that are subject to inundation. The western half of the county is typically rural in character, and land use is largely agricultural with some scattered forest land cover. Western Sussex County has several low-relief river flood-prone areas, where accurate high-resolution elevation data are needed for Federal Emergency Management Agency (FEMA) Digital Flood Insurance Rate Map (DFIRM) studies. This fact sheet describes the methods and techniques used to collect and process LiDAR elevation data, the generation of the digital elevation model (DEM) and the 2-foot contours, and the quality-assurance procedures and results. It indicates where to view metadata on the data sets and where to acquire bare-earth mass points, DEM data, and contour data.
Contamination of surface and ground water from non-point sources is a national issue. Examples of nonpoint-source contaminants from agricultural activities are pesticides, which include fungicides, herbicides, and insecticides; sediment; nutrients (nitrogen and phosphorus); and fecal bacteria. Of these contaminants, pesticides receive the most attention because of the potential toxicity to aquatic life and to humans. Most farmers use pesticides to increase crop yields and values. Herbicides prevent or inhibit the growth of weeds that compete for nutrients and moisture needed by the crops. Herbicides are applied before, during, or following planting. In addition to agricultural use, herbicides are used in urban areas, often in larger rates of application, for weed control such as among rights-of-way. Alachlor, atrazine, cyanazine, and metolachlor, which are referred to as organonitrogen herbicides, were the four most commonly applied herbicides (1991) in the Central Nebraska Basins (CNB). These herbicides are used for corn, sorghum, and soybean production. Atrazine was the most extensively applied pesticide (1991) in central Nebraska. Insecticides are used to protect the crop seeds in storage prior to planting and also to protect the plants from destruction once the seeds have germinated. Like herbicides, insecticides are also used in urban areas to protect lawns, trees, and ornamentals. Many of the 46 pesticides shown in the table have either a Maximum Contaminant Level (MCL) of Health Advisory Level (HAL) established by the U.S. Environmental Protection Agency (USEPA) for public water supplies. The purposes of this Fact Sheet are to (1) to provide water-utility managers, water-resources planners and managers, and State regulators an improved understanding of the distributions of concentrations of pesticides in streams and their relation to respective drinking-water regulations or criteria, and (2) to describe concentrations of pesticides in streams draining a selected small agricultural basin and a large agricultural area.
This Fact Sheet serves as an index to California ground-water data for 1996. The 2-page report contains a map of California showing the number of wells (by county) with available water-level and water- quality data for the current year and instructions for obtaining this and other ground-water information contained in the data bases of the Water Resources Division, California District.
The Chesapeake Bay Program maintains an extensive nontidal monitoring network, measuring nitrogen and phosphorus (nutrients) at more than 100 locations on rivers and streams in the watershed. Data from these locations are used by United States Geological Survey to assess the ecosystem’s response to nutrient-reduction efforts. This fact sheet summarizes recent trends in nitrogen and phosphorus in nontidal tributaries and identifies some of the complex factors that affect local water quality, and ultimately, the Chesapeake Bay.
The U.S. Geological Survey, Water Resources, in cooperation with Federal, State, and local agencies, obtains a large amount of data pertaining to the ground-water resources of California each water year (October 1?September 30). These data constitute a valuable database for developing an improved understanding of the water resources of the State. This Fact Sheet serves as an index to ground-water data for water year 2002. The 2-page report contains a map of California showing the number of wells (by county) with available water-level and waterquality data for water year 2002 and instructions for obtaining this and other ground-water information contained in the databases of the U.S. Geological Survey, Water Resources, California District.
The Invasive Species Science Branch of the Fort Collins Science Center provides research and technical assistance relating to management concerns for invasive species, including understanding how these species are introduced, identifying areas vulnerable to invasion, forecasting invasions, and developing control methods. This fact sheet considers the invasive plant species tamarisk (Tamarix spp), addressing three fundamental questions: *Where is it now? *What are the potential or realized ecological impacts of invasion? *Where can it survive and thrive if introduced? It provides peer-review examples of how the U.S. Geological Survey, working with other federal agencies and university partners, are applying remote-sensing technologies to address these key questions.
This fact sheet presents a brief overview of groundwater and surface-water resources in Jefferson Parish, Louisiana. Information on the availability, use, and quality of water from groundwater and surface-water sources in the parish is discussed. Previously published reports and data stored in the U.S. Geological Survey’s National Water Information System ( http://waterdata.usgs.gov/nwis ) are the primary sources of this information.
The Water Resources Division of the U.S. Geological Survey, in cooperation with Federal, State, and local water agencies, obtains a large amount of data pertaining to the ground-water resources of California each water year. These data constitute a valuable database for developing an improved understanding of the water resources of the State. Beginning with the 1985 water year and continuing through 1993, these data were published in a report series entitled ?Water Resources Data for California, Volume 5. Ground-Water Data.? Prior to the introduction of this series, historical ground-water information was published in U.S. Geological Survey Water-Supply Papers. In 1994, the Volume 5 Ground-Water Data report was discontinued, but data continue to be available in our databases. This Fact Sheet serves as an index to ground-water data for water year 2000. The 2-page report contains a map of California showing the number of wells (by county) with available water-level and water-quality data for water year 2000 (fig. 2) and instructions for obtaining this and other ground-water information contained in the databases of the Water Resources Division, California District.
This Fact Sheet is one in a series that highlights information or recent research findings from the USGS National Streamflow Information Program (NSIP). The investigations and scientific results reported in this series require a nationally consistent streamgaging network with stable long-term monitoring sites and a rigorous program of data quality assurance, management, archiving, and synthesis. NSIP produces multi-purpose, unbiased surface water information that is readily accessible to all.
The purpose of this fact sheet is to provide examples of how the U.S. Geological Survey is using acoustic Doppler current profilers for much more than routine discharge measurements. These instruments are capable of mapping complex three-dimensional flow fields within rivers, lakes, and estuaries. Using the Velocity Mapping Toolbox to process the ADCP data allows detailed visualization of the data, providing valuable information for a range of studies and applications.
The Water Resources Division of the U.S. Geological Survey, in cooperation with Federal, State, and local water agencies, obtains a large amount of data pertaining to the ground-water resources of California each water year. These data constitute a valuable data base for developing an improved understanding of the water resources of the State. Beginning with the 1985 water year and continuing through 1993, these data were published in a report series entitled 'Water Resources Data for California, Volume 5. Ground-Water Data.' Prior to the introduction of this series, historical ground-water information was published in U.S. Geological Survey Water-Supply Papers. In 1994, the Volume 5 Ground-Water Data report was discontinued, but data continue to be available in our data bases. This Fact Sheet serves as an index to ground-water data for 1997. The 2-page report contains a map of California showing the number of wells (by county) with available water-level and water-quality data for the current water year (fig. 2) and instructions for obtaining this and other ground-water information contained in the data bases of the Water Resources Division, California District.
The Water Resources Division of the U.S. Geological Survey, in cooperation with Federal, State, and local water agencies, obtains a large amount of data pertaining to the ground-water resources of California each water year. These data constitute a valuable data base for developing an improved understanding of the water resources of the State. Beginning with the 1985 water year and continuing through 1993, these data were published in a report series entitled ?Water Resources Data for California, Volume 5. Ground-Water Data.? Prior to the introduction of this series, historical ground-water information was published in U.S. Geological Survey Water-Supply Papers. In 1994, the Volume 5 Ground-Water Data report was discontinued, but data continue to be available in our data bases. This Fact Sheet serves as an index to ground-water data for 1999. The 2-page report contains a map of California showing the number of wells (by county) with available water-level and water-quality data for the current water year (fig. 2) and instructions for obtaining this and other ground-water information contained in the data bases of the Water Resources Division, California District.
The Water Resources Division of the U.S. Geological Survey, in cooperation with Federal, State, and local water agencies, obtains a large amount of data pertaining to the ground-water resources of California each water year. These data constitute a valuable data base for developing an improved understanding of the water resources of the State. Beginning with the 1985 water year and continuing through 1993, these data were published in a report series entitled ?Water Resources Data for California, Volume 5. Ground-Water Data.? Prior to the introduction of this series, historical ground-water information was published in U.S. Geological Survey Water-Supply Papers. In 1994, the Volume 5 Ground-Water Data report was discontinued, but data continue to be available in our data bases. This Fact Sheet serves as an index to ground-water data for 1998. The 2-page report contains a map of California showing the number of wells (by county) with available water-level and water-quality data for the current water year (fig. 2) and instructions for obtaining this and other ground-water information contained in the data bases of the Water Resources Division, California District.
This Fact Sheet is one in a series that highlights information or recent research findings from the USGS National Streamflow Information Program (NSIP). The investigations and scientific results reported in this series require a nationally consistent streamgaging network with stable long-term monitoring sites and a rigorous program of data quality assurance, management, archiving, and synthesis. NSIP produces multi-purpose, unbiased surface water information that is readily accessible to all.
This fact sheet describes the results of a water-use study for West Virginia that was conducted by the U.S. Geological Survey (USGS), in cooperation with the West Virginia Geological and Economic Survey (WVGES), as part of the National Water-Use Information Program of the USGS. The national program is based on Federal and State cooperative agreements to collect, store, and disseminate water-use information nationally and locally.
This Fact Sheet is one in a series that highlights information or recent research findings from the USGS National Streamflow Information Program (NSIP). The investigations and scientific results reported in this series require a nationally consistent streamgaging network with stable long-term monitoring sites and a rigorous program of data quality assurance, management, archiving, and synthesis. NSIP produces multi-purpose, unbiased surface water information that is readily accessible to all.