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.
Learn more: Groundwater Use
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Estimated use of water in the United States in 2015
Water use in the United States in 2015 was estimated to be about 322 billion gallons per day (Bgal/d), which was 9 percent less than in 2010. The 2015 estimates put total withdrawals at the lowest level since before 1970, following the same overall trend of decreasing total withdrawals observed from 2005 to 2010. Freshwater withdrawals were 281...
Dieter, Cheryl A.; Maupin, Molly A.; Caldwell, Rodney R.; Harris, Melissa A.; Ivahnenko, Tamara I.; Lovelace, John K.; Barber, Nancy L.; Linsey, Kristin S.
The quality of our Nation's waters: Water quality in principal aquifers of the United States, 1991-2010
About 130 million people in the United States rely on groundwater for drinking water, and the need for high-quality drinking-water supplies becomes more urgent as our population grows. Although groundwater is a safe, reliable source of drinking water for millions of people nationwide, high concentrations of some chemical constituents can pose...
DeSimone, Leslie A.; McMahon, Peter B.; Rosen, Michael R.
Summary of estimated water use in the United States in 2010
About 355,000 million gallons per day (Mgal/d) of water was withdrawn for use in the United States during 2010, a decline of 13 percent from 2005 and a substantial change from the level of about 400,000 Mgal/d reported from 1985 to 2005. Withdrawals for 2010 were lower than withdrawals estimated for 1970. Fresh surface-water withdrawals (230,000...
Barber, Nancy L.
Groundwater studies: principal aquifer surveys
In 1991, the U.S. Congress established the National Water-Quality Assessment (NAWQA) program within the U.S. Geological Survey (USGS) to develop nationally consistent long-term datasets and provide information about the quality of the Nation’s streams and groundwater. The USGS uses objective and reliable data, water-quality models, and systematic...
Burow, Karen R.; Belitz, Kenneth
Sustainability of ground-water resources
The pumpage of fresh ground water in the United States in 1995 was estimated to be approximately 77 billion gallons per day (Solley and others, 1998), which is about 8 percent of the estimated 1 trillion gallons per day of natural recharge to the Nation's ground-water systems (Nace, 1960). From an overall national perspective, the ground-water...
Alley, William M.; Reilly, Thomas E.; Franke, O. Lehn
Ground water and surface water; a single resource
The importance of considering ground water and surface water as a single resource has become increasingly evident. Issues related to water supply, water quality, and degradation of aquatic environments are reported on frequently. The interaction of ground water and surface water has been shown to be a significant concern in many of these issues....
Winter, Thomas C.; Harvey, Judson W.; Franke, O. Lehn; Alley, William M.
Ground water and the rural homeowner
As the salesmen sang in the musical The Music Man, "You gotta know the territory." This saying is also true when planning to buy or build a house. Learn as much as possible about the land, the water supply, and the septic system of the house before buying or building. Do not just look at the construction aspects or the beauty of the home and...
Waller, Roger M. What is ground water?
Clark, David W.; Briar, David W.
Study Estimates about 2.1 Million People using Wells High in Arsenic
Most Arsenic Presumed to be From Naturally Occurring Sources
How Well Do You Know Groundwater
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!
How Much Water Do We Use?
The USGS National Water-Use Science project has documented 60 years of water-use from 1950 to 2010 in an interactive map. Choose a year and pick a category to see how much water your state uses.
Helping Desert Communities Find Hidden Water
Desert communities throughout the Southwest are putting water availability at the top of their municipal agendas.
Large Precipitation Events are Critical in Replenishing Groundwater Resources
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.
Land Subsidence near El Nido, CA
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
...
Land Subsidence near El Nido, CA
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
...
Groundwater decline: Irrigation of plants often uses groundwater
Groundwater, which is found in aquifers below the surface of the earth, is one of the nation's most important natural resources. Groundwater provides drinking water for a large portion of the nation's population, supplies business and industries, and is used extensively for irrigation.
Droughts, seasonal variations in precipitation, and pumping affect the height of
...
PubTalk 11/2014 — Water, Nuts, and the Nation's Fruit Bowl
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
PubTalk 9/2011 — Tracking the Nation's Groundwater Reserves
--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
USGS employee sampling an urban groundwater well
USGS employee sampling an urban groundwater well. Photo from USGS circular 1352 "Water quality in the Glacial Aquifer System, Northern United States, 1993 - 2009.
Irrigation groundwater well
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
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."
Windmill for pumping groundwater in the Klamath Basin
Groundwater can flow to the land surface as springs
Groundwater flowing out of Minnie Miller Springs, Idaho, USA.
Groundwater Water Education Poster, Middle School
Water Education Poster of Groundwater, Middle School