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How important is groundwater?
Groundwater, which is in aquifers below the surface of the Earth, is one of the Nation's most important natural resources. Groundwater is the source of about 37 percent of the water that county and city water departments supply to households and businesses (public supply). It provides drinking water for more than 90 percent of the rural population who do not get their water delivered to them from a county/city water department or private water company.
Even some major cities, such as San Antonio, Texas, rely solely on groundwater for all their needs. About 42 percent of the water used for irrigation comes from groundwater.
Withdrawals of groundwater are expected to rise as the population increases and available sites for surface reservoirs become more limited.
Most Arsenic Presumed to be From Naturally Occurring Sources
Groundwater, which flows out of sight through aquifers beneath our feet, is one of the Nation’s most important natural resources. In recognition of National Groundwater Awareness Week, March 5–11, 2017, here’s an opportunity to put your knowledge of this vital resource to the test!
Desert communities throughout the Southwest are putting water availability at the top of their municipal agendas.
Large precipitation events that occur about every 10 years are a critical source of recharge for replenishing groundwater resources, according to a new study by the U.S. Geological Survey and the Bureau of Reclamation.
National Geodetic Survey vertical control bench mark H1235 RESET in Merced County, California. H 1235 RESET is in the median of State Highway 15. This is one of several bench mark locations used to help measure the largest recent subsidence in the area using repeat surveys. The exact maximum subsidence location is unknown; however, this bench mark has some of the larger...
National Geodetic Survey vertical control bench mark W990 CADWR in Merced County, California. W 990 CADWR is on the Mariposa Bypass Bridge on Washington Rd. This is one of several bench mark locations used to help measure the largest recent subsidence in the area using repeat surveys. The exact maximum subsidence location is unknown; however, this bench mark has some of...
California's Central Valley Hydrologic Science
by Claudia Faunt, USGS Hydrologist
- Using about 1% of U.S. farmland, California's Central Valley supplies 7% of the U.S. agricultural output (by value) -- 1/4 of the Nation's food, including about half of the Nation's fruits, nuts, and vegetables.
- Approximately 20
--issues facing current and future water supplies
by William Alley, USGS Office of Groundwater
- Ground water is among the Nation's most important natural resources, providing half of our drinking water as well as being essential to agriculture and industry, and the health of ecosystems throughout the country
Irrigation groundwater well. Photo from USGS circular 1356 "Water Quality in the Mississippi Embayment-Texas Coastal Uplands Aquifer System and Mississippi River Valley Alluvial Aquifer, South-Central United States, 1994-2008."
Irrigation water from a groundwater well on a rice crop field. Photo from USGS circular 1356 "Water Quality in the Mississippi Embayment-Texas Coastal Uplands Aquifer System and Mississippi River Valley Alluvial Aquifer, South-Central United States, 1994-2008."
Groundwater flowing out of Minnie Miller Springs, Idaho, USA.