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A well is said to have gone dry when water levels drop below a pump intake. This does not mean that a dry well will never have water in it again, as the water level may come back through time as recharge increases. The water level in a well depends on a number of things, such as the depth of the well, the type (confined or unconfined) of aquifer the well taps, the amount of pumping that occurs in this aquifer, and the amount of recharge occurring. Wells screened in unconfined water table aquifers are more directly influenced by the lack of rain than those screened in deeper confined aquifers. A deep well in a confined aquifer in an area with minimal pumping is less likely to go dry than a shallow, water table well.
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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...
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...
What is groundwater?
Groundwater is water that exists underground in saturated zones beneath the land surface. The upper surface of the saturated zone is called the water table. Contrary to popular belief, groundwater does not form underground rivers. It fills the pores and fractures in underground materials such as sand, gravel, and other rock, much the same way that water fills a sponge. If groundwater flows...
Groundwater is water that exists underground in saturated zones beneath the land surface. The upper surface of the saturated zone is called the water table. Contrary to popular belief, groundwater does not form underground rivers. It fills the pores and fractures in underground materials such as sand, gravel, and other rock, much the same way that water fills a sponge. If groundwater flows...
How can I find the depth to the water table in a specific location?
The depth to the water table can change (rise or fall) depending on the time of year. During the late winter and spring when accumulated snow starts to melt and spring rainfall is plentiful, water on the surface infiltrates into the ground and the water table rises. When water-loving plants start to grow again in the spring and precipitation gives way to hot, dry summers, the water table falls...
The depth to the water table can change (rise or fall) depending on the time of year. During the late winter and spring when accumulated snow starts to melt and spring rainfall is plentiful, water on the surface infiltrates into the ground and the water table rises. When water-loving plants start to grow again in the spring and precipitation gives way to hot, dry summers, the water table falls...
What is the Ground Water Atlas of the United States?
This Ground Water Atlas of the United States is a series of USGS publications that describe the location, the extent, and the geologic and hydrologic characteristics of the important aquifers of the Nation. The series consists of 13 chapters that describe the regional groundwater resources that collectively cover 50 States, Puerto Rico, and the U.S. Virgin Islands. Learn more: Principal Aquifers...
This Ground Water Atlas of the United States is a series of USGS publications that describe the location, the extent, and the geologic and hydrologic characteristics of the important aquifers of the Nation. The series consists of 13 chapters that describe the regional groundwater resources that collectively cover 50 States, Puerto Rico, and the U.S. Virgin Islands. Learn more: Principal Aquifers...
Flowing groundwater site in Indiana
Flowing groundwater site in Indiana
Flowing groundwater site in Indiana
Flowing well used for stock water, Green River Basin
Flowing well used for stock water, Green River Basin
Flowing well used for stock water, Green River Basin
Flowing well used for stock water, Green River Basin
Flowing well used for stock water, Green River Basin
PubTalk 9/2011 — Tracking the Nation's Groundwater Reserves
PubTalk 9/2011 — Tracking the Nation's Groundwater Reserves
PubTalk 9/2011 — Tracking the Nation's Groundwater Reserves
--issues facing current and future water supplies
by William Alley, USGS Office of Groundwater
--issues facing current and future water supplies
by William Alley, USGS Office of Groundwater
Well, Well, Well! How Deep is the Water Table?
This month we highlight a new interactive map that allows users to determine the depth to groundwater at any location in the Portland Metropolitan Area, Oregon. This month's episode features an interview with the groundwater project's lead author, USGS hydrologist Daniel Snyder.
This month we highlight a new interactive map that allows users to determine the depth to groundwater at any location in the Portland Metropolitan Area, Oregon. This month's episode features an interview with the groundwater project's lead author, USGS hydrologist Daniel Snyder.
Water Well
Irrigation well in northeastern Arkansas (U.S. Geological Survey photograph by Terrance W. Holland, 2009).
Irrigation well in northeastern Arkansas (U.S. Geological Survey photograph by Terrance W. Holland, 2009).
Water-level and recoverable water in storage changes, High Plains Aquifer, predevelopment to 2019 and 2017 to 2019
The High Plains aquifer underlies 111.8 million acres (about 175,000 square miles) in parts of eight States: Colorado, Kansas, Nebraska, New Mexico, Oklahoma, South Dakota, Texas, and Wyoming. Water-level declines began in parts of the High Plains aquifer soon after the beginning of substantial groundwater irrigation (about 1950). This report presents water-level changes and change in recoverable
Authors
Virginia L. McGuire, Kellan R. Strauch
Availability of groundwater from the volcanic aquifers of the Hawaiian Islands
The islands of Hawaiʻi were built by basaltic shield volcanoes in the Pacific Ocean. These volcanoes formed aquifers that supply hundreds of millions of gallons of fresh water per day to the islands’ residents and diverse industries. Groundwater discharge from the volcanic aquifers to streams and the coast also supports traditional practices and ecosystems. The aquifers' capacity to yield fresh gr
Authors
Scot K. Izuka, Kolja Rotzoll
Climate change: evaluating your local and regional water resources
The BCM is a fine-scale hydrologic model that uses detailed maps of soils, geology, topography, and transient monthly or daily maps of potential evapotranspiration, air temperature, and precipitation to generate maps of recharge, runoff, snow pack, actual evapotranspiration, and climatic water deficit. With these comprehensive environmental inputs and experienced scientific analysis, the BCM provi
Authors
Lorraine E. Flint, Alan L. Flint, James H. Thorne
Estimated use of water in the United States in 2010
Water use in the United States in 2010 was estimated to be about 355 billion gallons per day (Bgal/d), which was 13 percent less than in 2005. The 2010 estimates put total withdrawals at the lowest level since before 1970. Freshwater withdrawals were 306 Bgal/d, or 86 percent of total withdrawals, and saline-water withdrawals were 48.3 Bgal/d, or 14 percent of total withdrawals. Fresh surface-wate
Authors
Molly A. Maupin, Joan F. Kenny, Susan S. Hutson, John K. Lovelace, Nancy L. Barber, Kristin S. Linsey
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 Mgal/d) were almost 15 percent less than in 2005, an
Authors
Nancy L. Barber
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 scientific studies to assess current water-quality
Authors
Karen R. Burow, Kenneth Belitz
Land subsidence in the United States
No abstract available.
Authors
Devin L. Galloway, David R. Jones, S. E. Ingebritsen
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 resource appears ample. Locally, however, the availabi
Authors
William M. Alley, Thomas E. Reilly, O. Lehn Franke
Land subsidence in the United States
This report explores the role of science in defining and understanding subsidence problems, and shows that the optimal use of our land and water resources may depend on improved scientific understanding to minimize subsidence. More than 80 percent of the identified land subsidence in the Nation is a consequence of human impact on subsurface water, and is an often overlooked environmental consequen
Authors
Devin L. Galloway, David R. Jones, S. E. Ingebritsen
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 surroundings. Be sure to consider the environmental cond
Authors
Roger M. Waller
How Well Do You Know Groundwater
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 Na...
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...
Large Precipitation Events are Critical in Replenishing Groundwater Resources
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 ne...
Unprecedented Drought in the West
Unprecedented Drought in the West
Drought has left the West parched and thirsty. Families, businesses, and farmers all need water, as do fish, wildlife, and their habitats.
Related Content
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...
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...
What is groundwater?
Groundwater is water that exists underground in saturated zones beneath the land surface. The upper surface of the saturated zone is called the water table. Contrary to popular belief, groundwater does not form underground rivers. It fills the pores and fractures in underground materials such as sand, gravel, and other rock, much the same way that water fills a sponge. If groundwater flows...
Groundwater is water that exists underground in saturated zones beneath the land surface. The upper surface of the saturated zone is called the water table. Contrary to popular belief, groundwater does not form underground rivers. It fills the pores and fractures in underground materials such as sand, gravel, and other rock, much the same way that water fills a sponge. If groundwater flows...
How can I find the depth to the water table in a specific location?
The depth to the water table can change (rise or fall) depending on the time of year. During the late winter and spring when accumulated snow starts to melt and spring rainfall is plentiful, water on the surface infiltrates into the ground and the water table rises. When water-loving plants start to grow again in the spring and precipitation gives way to hot, dry summers, the water table falls...
The depth to the water table can change (rise or fall) depending on the time of year. During the late winter and spring when accumulated snow starts to melt and spring rainfall is plentiful, water on the surface infiltrates into the ground and the water table rises. When water-loving plants start to grow again in the spring and precipitation gives way to hot, dry summers, the water table falls...
What is the Ground Water Atlas of the United States?
This Ground Water Atlas of the United States is a series of USGS publications that describe the location, the extent, and the geologic and hydrologic characteristics of the important aquifers of the Nation. The series consists of 13 chapters that describe the regional groundwater resources that collectively cover 50 States, Puerto Rico, and the U.S. Virgin Islands. Learn more: Principal Aquifers...
This Ground Water Atlas of the United States is a series of USGS publications that describe the location, the extent, and the geologic and hydrologic characteristics of the important aquifers of the Nation. The series consists of 13 chapters that describe the regional groundwater resources that collectively cover 50 States, Puerto Rico, and the U.S. Virgin Islands. Learn more: Principal Aquifers...
Flowing groundwater site in Indiana
Flowing groundwater site in Indiana
Flowing groundwater site in Indiana
Flowing well used for stock water, Green River Basin
Flowing well used for stock water, Green River Basin
Flowing well used for stock water, Green River Basin
Flowing well used for stock water, Green River Basin
Flowing well used for stock water, Green River Basin
PubTalk 9/2011 — Tracking the Nation's Groundwater Reserves
PubTalk 9/2011 — Tracking the Nation's Groundwater Reserves
PubTalk 9/2011 — Tracking the Nation's Groundwater Reserves
--issues facing current and future water supplies
by William Alley, USGS Office of Groundwater
--issues facing current and future water supplies
by William Alley, USGS Office of Groundwater
Well, Well, Well! How Deep is the Water Table?
This month we highlight a new interactive map that allows users to determine the depth to groundwater at any location in the Portland Metropolitan Area, Oregon. This month's episode features an interview with the groundwater project's lead author, USGS hydrologist Daniel Snyder.
This month we highlight a new interactive map that allows users to determine the depth to groundwater at any location in the Portland Metropolitan Area, Oregon. This month's episode features an interview with the groundwater project's lead author, USGS hydrologist Daniel Snyder.
Water Well
Irrigation well in northeastern Arkansas (U.S. Geological Survey photograph by Terrance W. Holland, 2009).
Irrigation well in northeastern Arkansas (U.S. Geological Survey photograph by Terrance W. Holland, 2009).
Water-level and recoverable water in storage changes, High Plains Aquifer, predevelopment to 2019 and 2017 to 2019
The High Plains aquifer underlies 111.8 million acres (about 175,000 square miles) in parts of eight States: Colorado, Kansas, Nebraska, New Mexico, Oklahoma, South Dakota, Texas, and Wyoming. Water-level declines began in parts of the High Plains aquifer soon after the beginning of substantial groundwater irrigation (about 1950). This report presents water-level changes and change in recoverable
Authors
Virginia L. McGuire, Kellan R. Strauch
Availability of groundwater from the volcanic aquifers of the Hawaiian Islands
The islands of Hawaiʻi were built by basaltic shield volcanoes in the Pacific Ocean. These volcanoes formed aquifers that supply hundreds of millions of gallons of fresh water per day to the islands’ residents and diverse industries. Groundwater discharge from the volcanic aquifers to streams and the coast also supports traditional practices and ecosystems. The aquifers' capacity to yield fresh gr
Authors
Scot K. Izuka, Kolja Rotzoll
Climate change: evaluating your local and regional water resources
The BCM is a fine-scale hydrologic model that uses detailed maps of soils, geology, topography, and transient monthly or daily maps of potential evapotranspiration, air temperature, and precipitation to generate maps of recharge, runoff, snow pack, actual evapotranspiration, and climatic water deficit. With these comprehensive environmental inputs and experienced scientific analysis, the BCM provi
Authors
Lorraine E. Flint, Alan L. Flint, James H. Thorne
Estimated use of water in the United States in 2010
Water use in the United States in 2010 was estimated to be about 355 billion gallons per day (Bgal/d), which was 13 percent less than in 2005. The 2010 estimates put total withdrawals at the lowest level since before 1970. Freshwater withdrawals were 306 Bgal/d, or 86 percent of total withdrawals, and saline-water withdrawals were 48.3 Bgal/d, or 14 percent of total withdrawals. Fresh surface-wate
Authors
Molly A. Maupin, Joan F. Kenny, Susan S. Hutson, John K. Lovelace, Nancy L. Barber, Kristin S. Linsey
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 Mgal/d) were almost 15 percent less than in 2005, an
Authors
Nancy L. Barber
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 scientific studies to assess current water-quality
Authors
Karen R. Burow, Kenneth Belitz
Land subsidence in the United States
No abstract available.
Authors
Devin L. Galloway, David R. Jones, S. E. Ingebritsen
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 resource appears ample. Locally, however, the availabi
Authors
William M. Alley, Thomas E. Reilly, O. Lehn Franke
Land subsidence in the United States
This report explores the role of science in defining and understanding subsidence problems, and shows that the optimal use of our land and water resources may depend on improved scientific understanding to minimize subsidence. More than 80 percent of the identified land subsidence in the Nation is a consequence of human impact on subsurface water, and is an often overlooked environmental consequen
Authors
Devin L. Galloway, David R. Jones, S. E. Ingebritsen
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 surroundings. Be sure to consider the environmental cond
Authors
Roger M. Waller
How Well Do You Know Groundwater
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 Na...
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...
Large Precipitation Events are Critical in Replenishing Groundwater Resources
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 ne...
Unprecedented Drought in the West
Unprecedented Drought in the West
Drought has left the West parched and thirsty. Families, businesses, and farmers all need water, as do fish, wildlife, and their habitats.
