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All Groundwater Availability Products
Pumping and Groundwater Decreases in Edwards-Trinity Aquifer in Texas –USGS, in cooperation with the Middle Pecos Groundwater Conservation District, Pecos County, City of Fort Stockton, Brewster County, and Pecos County Water Control and Improvement District No. 1, developed a groundwater-flow model of the Edwards-Trinity and related aquifers in parts of Brewster, Jeff Davis, Pecos, and Reeves Counties. The model was used to simulate groundwater levels resulting from prolonged pumping to evaluate sustainability of current and projected water-use demands. Scientists analyzed three scenarios to simulate a 30-year period from 2010 to 2040. Findings showed that an increase in pumping water year-round for the next 30 years may cause groundwater levels to decrease by as much as 32 feet in parts of the Edwards-Trinity Aquifer in west Texas. The Edwards-Trinity Aquifer in west Texas is a vital groundwater resource for agricultural, industrial, and public supply uses in the Pecos County region. Resource managers would like to understand the future availability of water in the Edwards-Trinity Aquifer and the effects of pumping or redistribution of groundwater resources over time. (Press release; Report)
Saltwater Intrusion in the Biscayne Aquifer, Florida –USGS, in cooperation with Miami-Dade County, have depicted saltwater intrusion in the Biscayne aquifer, which will help water managers protect the primary drinking water source for the county’s roughly 2.5 million residents. The new study, which uses information gathered through 2011, found that saltwater had intruded about 460 square miles of the mainland part of the county. The new report provides an updated understanding of the extent of saltwater in the aquifer, describing where saltwater has further intruded since last being mapped in 1995, where it has been pushed back toward the ocean and where it’s leaking from canals. Saltwater intrusion began in the area early in the 20th century when canals were dredged to drain the Everglades. As water levels in the Biscayne aquifer declined, saltwater from the ocean flowed inland along its base. (Press Release)
Groundwater Study Assesses Potential for Contamination of Drinking-Water Aquifers in Los Angeles, California –USGS, in cooperation with the Water Replenishment District of Southern California, reported that contaminated groundwater found at shallow depths in the northeastern portion of the Central Groundwater Basin in southern California could migrate to greater depths where many drinking water supply wells are located. Over two million residents get approximately 60 percent of their drinking water supply from these deeper aquifers. There are multiple sites in the northeast portion of the basin where shallow groundwater contamination is already being investigated and remediated under the oversight of several federal and state regulatory agencies. The results of this study will allow the Water Replenishment District to anticipate possible future contaminant migration and to plan accordingly to protect uncontaminated areas. Additionally, regulatory agencies can use the study results to inform future monitoring and cleanup actions for contaminated sites located in the Central Groundwater Basin. (Press Release; Report)
Groundwater Potential Mapped in the Susquehanna River Valley, New York –USGS, in cooperation with New York State Department of Environmental Conservation, assessed and mapped a variety of aquifer types and described their current use and potential as groundwater sources in the valley-fill aquifer along a 32 mile reach of the Susquehanna River valley and adjacent areas was evaluated in eastern Broome and southeastern Chenango Counties, New York. The study area includes part of south-central New York that has substantial natural gas potential in the underlying Marcellus and Utica shale formations. Findings help managers make decisions on future groundwater use and protection. (Press release; Report and interactive map)
Declines in Groundwater Levels in the Columbia Plateau Regional Aquifer, Washington, Oregon, and Idaho –The USGS Groundwater Resources Program and Cooperative Water Program, in cooperation with the Oregon Water Resources Department, compiled and analyzed well information and groundwater levels collected by USGS and seven other organizations. The data were used to develop a simple linear groundwater-level trends map of the aquifers of the Columbia River Basalt Groups for 1968-2009. Geologic barriers, the intermixing of water between aquifers through wells, and groundwater pumping contribute to a pattern of declines of groundwater levels of the Columbia Plateau (Press release; Report)
Water Quality in the Fayetteville Shale Gas-Production Area, North-Central Arkansas –USGS, in cooperation with the Arkansas Natural Resources Commission, Arkansas Oil and Gas Commission, Duke University, Faulkner County, Shirley Community Development Corporation, and the University of Arkansas at Fayetteville, examined water quality in 127 shallow domestic wells in the Fayetteville Shale natural gas production area of Arkansas and found no groundwater contamination associated with gas production. Scientists analyzed water-quality data from samples taken in Van Buren and Faulkner counties in 2011, focusing on chloride concentrations from 127 wells and methane concentrations and carbon isotope ratios from a subsample of 51 wells. Chloride is a naturally occurring ion that is found at elevated levels in waters associated with gas production. Chloride moves easily through groundwater without reacting with other ions or compounds in solution, which thereby makes it a good indicator of whether chemicals used during hydraulic fracturing are reaching groundwater. In this case, the chloride concentrations from this study were not higher than samples taken from nearby areas from 1951 through 1983. Methane is the primary component of natural gas, but also can be found naturally in shallow shale formations in the Fayetteville Shale area that are used as sources of water for domestic supplies. What methane was found in the water, taken from domestic wells, was either naturally occurring, or could not be attributed to natural gas production activities. (Full report; Press release)
Current and Future Groundwater Withdrawals in Coastal New Jersey –USGS, in cooperation with the New Jersey Department of Environmental Protection, simulated effects of alternative withdrawal strategies on groundwater flow in the unconfined Kirkwood-Cohansey aquifer system and the confined Atlantic City 800-foot sand, which are major sources of groundwater in the coastal region. The study area encompasses Atlantic County and parts of Burlington, Camden, Gloucester, Ocean, Cape May, and Cumberland Counties in New Jersey. A groundwater flow model was used to simulate scenarios under three possible withdrawal conditions: average 1998 to 2006 withdrawals, full-allocation withdrawals, and projected 2050-demand withdrawals. Results were compared with baseline conditions (no withdrawals) to determine where and when base-flow deficits may be occurring and may be expected to occur in the future. (Full report)
Groundwater Monitoring Plan for the Missouri River Alluvial Aquifer –USGS, in cooperation with the City of Independence, Missouri assessed source contributions to monitoring and supply wells, contributing recharge areas, groundwater travel times, and alluvial water quality to develop a groundwater monitoring plan for the Missouri River alluvial aquifer in the vicinity of the City of Independence, Missouri well field. Source contributions were determined from an existing groundwater flow model in conjunction with particle-tracking analysis and verified with water-quality data collected from 1997 through 2010 from a network of 68 monitoring wells. Three conjunctive factors—well-field pumpage, Missouri River discharge, and aquifer recharge—largely determined groundwater flow and, therefore, source contributions. The predominant source of groundwater to most monitoring wells and supply wells is the Missouri River, and this was reflected, to some extent, in alluvial water quality. To provide an estimate of the maximum potential lead time available for remedial action, monitoring wells where groundwater travel times from the contributing recharge areas are less than 2 years and predominately singular sources (such as the Missouri River or the land surface) were selected for annual sampling. (Full report)
Geophysical Information Used to Identify the Base of the High Plains Aquifer System in Elkhorn and Loup River Basins, Nebraska –USGS, in cooperation with the Nebraska Department of Natural Resources; and the Upper Elkhorn, Lower Elkhorn, Upper Loup, Lower Loup, Middle Niobrara, Lower Niobrara, Lewis and Clark, and Lower Platte North Natural Resources Districts; and the University of Nebraska-Lincoln Conservation and Survey Division, described the subsurface lithology at six test holes drilled in 2010 and concurrently collected borehole geophysical data to identify the base of the High Plains aquifer system. A total of 124 time-domain electromagnetic soundings of resistivity were collected at and between selected test-hole locations during 2008–11 as a quick, non-invasive means of identifying the base of the High Plains aquifer system. The geophysical and subsurface geological information is critical to ultimately understand the effects of groundwater management and pumping scenarios on surface-water resources. (Full report)
Groundwater Availability in the Glacial Aquifer System near Aberdeen, South Dakota –USGS, in cooperation with the city of Aberdeen, developed a conceptual and numerical model of the glacial aquifer system north of Aberdeen, South Dakota, that can be used to evaluate and manage the city of Aberdeen's water resources. The glacial aquifer system in the model area includes the Elm, Middle James, and Deep James aquifers, with intervening confining units composed of glacial till. (Full report)
Projected Water Use and Groundwater Scenarios through 2060 in Parts of Nevada and California –USGS, in cooperation with the Carson Water Subconservancy District, assessed potential effects of changes in water use with a numerical groundwater flow model of Carson Valley, Douglas County, Nevada, and Alpine County, California. Rapid growth and development within Carson Valley in Douglas County, Nevada, and Alpine County, California has caused concern over the continued availability of groundwater, and whether the increased municipal demand could either impact the availability of water or result in decreased flow in the Carson River. The groundwater-flow model was used in five 55-year predictive simulations to evaluate the long-term effects of different water-use scenarios on water-budget components, groundwater levels, and streamflow in the Carson River. The predictive simulations represented water years 2006 through 2060. (Full report)
Assessing Water Supply in the Fractured Rock Region in Maryland –USGS, in collaboration with the Maryland (MD) Department of the Environment, the MD Geological Survey, and the MD Department of Natural Resources, developed a science plan to provide new scientific information, new data analysis, and new tools for the State to comprehensively assess and manage water resources in the fractured rock region of Maryland (Science Plan). The fractured rock region of Maryland, which includes land areas north and west of the Interstate 95 corridor, is the source of water supply for approximately 4.4 million Marylanders, or approximately 76 percent of the State's population. Whereas hundreds of thousands of residents rely on wells (both domestic and community), millions rely on surface-water sources. In this region, land use, geology, topography, water withdrawals, impoundments, and other factors affect water-flow characteristics. The unconfined groundwater systems are closely interconnected with rivers and streams, and are affected by seasonal and climatic variations. During droughts, groundwater levels drop and contribute to reduced streamflows, which in turn, can lead to reduced habitat for aquatic life. Increased demand, over-allocation, population growth, and climate change can affect the future sustainability of water supplies in the region of Maryland underlain by fractured rock.
Groundwater Flow and Water Budget in East Central Florida –USGS, in cooperation with the St. Johns River Water Management District, South Florida Water Management District, and Southwest Florida Water Management District, developed a three dimensional model and water budget of the surficial and Floridan aquifer systems in east-central Florida. The study helps to (1) increase the understanding of water exchanges between the surficial and the Floridan aquifer systems, (2) assess the recharge rates to the surficial aquifer system from infiltration through the unsaturated zone and (3) obtain a simulation tool that could be used by water-resource managers to assess the impact of changes in groundwater withdrawals on spring flows and on the potentiometric surfaces of the hydrogeologic units composing the Floridan aquifer system. (Full report)
New Project on the Interstate 94 Growth Corridor in Minnesota –One of the fastest growing areas of Minnesota occurs between the Twin Cities and St. Cloud, often termed the Interstate 94 (I-94) growth corridor (Corridor). Such growth not only increases demands for domestic water resources, but expands the already high demands for industry and agricultural irrigation. In order to assess groundwater sustainability in the I-94 growth corridor, a 4-year, collaborative effort between the Minnesota Department of Natural Resources (DNR) and the USGS will provide a foundation to inform local agency partners and communities in planning for sustainable future land and water use. The USGS will collect continuous groundwater levels from representative sites in the Corridor and gather water use data to assist in a groundwater mass-balance analysis of the surficial aquifer of the Anoka Sand Plain. The focus on sustainability will help characterize the groundwater balance - the full inventory and all major flows and exchanges - that can be used to support human and ecosystem needs now and in the future. (Contact: Erik Smith, (763) 783-3100, firstname.lastname@example.org)
Million Year Old Groundwater in Maryland Water Supply –A new study from the USGS, the Maryland Geological Survey (MGS) and the Maryland Department of the Environment (MDE) documents for the first time the occurrence of groundwater that is more than one million years old in a major water-supply aquifer along the Atlantic Coast. This study reveals that modern pumping in southern Maryland west of the Chesapeake Bay and on the Eastern Shore is tapping groundwater resources that have accumulated in the aquifer over multiple cycles of climate change and are not quickly recharging. Such information will be used by the Maryland Department of the Environment to ensure that the management and use of the State's groundwater resources are being carried out to protect its long-term sustainability. (Hydrogeology Journal online; Press release)
Groundwater availability in the mountain valleys of Idaho –USGS, in cooperation with Blaine County, Idaho, released a report on groundwater resources in the mountainous Wood River Valley supporting Blaine County and the cities of Sun Valley, Ketchum, Hailey, and Bellevue, Idaho. The entire population of the area depends on groundwater for domestic supply, either from domestic or municipal-supply wells. Rapid population growth since the 1970s has caused concern about the long-term sustainability of the groundwater resource. USGS data and interpretations about the water resources of the Wood River Valley enable county and local governments to make informed decisions about water resources to meet future needs.
Sustaining high quality fresh groundwater on the islands of Hawai`i –Two USGS reports were released that assess current and future groundwater sustainability in freshwater-lens systems overlying saline coastal waters in the islands of Hawai`I, controlled in large part of volcanic rocks that form the aquifers. Specifically, USGS, in cooperation with the County of Maui Department of Water Supply, released a report and model of groundwater flow and effects on saline transport in the freshwater lens underlying West Maui under different pumping scenarios through 2030. Because of population growth, groundwater withdrawals from wells in this area are expected to double by 2030, which has led to concern over unpalatable saline waters and the long-term sustainability of withdrawals from existing and proposed wells. USGS, in cooperation with the Honolulu Board of Water Supply, released a report on the availability of freshwater in the heavily used Pearl Harbor aquifer in southern O`ahu, Salinity profiles are collected from wells that penetrate the freshwater lens into underlying saltwater to monitor changes in the freshwater-lens thickness.
Groundwater Flow in the Arbuckle-Simpson Aquifer, South-Central Oklahoma –USGS, in cooperation with the Oklahoma Water Resources Board, Bureau of Reclamation, Oklahoma State University, and the University of Oklahoma, characterized the hydrogeology and simulated groundwater flow in the Arbuckle-Simpson aquifer to help determine the volume of water that could be withdrawn while protecting springs and streams. The Arbuckle-Simpson aquifer provides water for public supply, farms, mining, wildlife conservation, recreation, and scenic beauty. (USGS report)
Groundwater conditions throughout Utah –USGS, in collaboration with the Utah Department of Natural Resources, Division of Water Resources and Division of Water Rights and the Utah Department of Environmental Quality, Division of Water Quality, describe groundwater conditions throughout Utah, published in a Cooperative Investigations Report (no. 51). This report includes maps depicting comparisons of 30-year changes (1980 to 2010) in water levels for each of the major areas of groundwater development. Groundwater chemistry associated with water samples collected from each area of groundwater development were compared to State of Utah maximum contaminant levels (MCLs) and secondary drinking-water standards of routinely measureable substances present in water supplies.
Water budgets for abandoned underground mines in Pennsylvania –A USGS report, prepared in cooperation with the Pennsylvania Department of Environmental Protection, the Eastern Pennsylvania Coalition for Abandoned Mine Reclamation, and the Dauphin County Conservation District, provides estimates of water budgets and groundwater volumes stored in abandoned underground mines in the Western Middle Anthracite Coalfield, which encompasses an area of 120 square miles in eastern Pennsylvania.