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 naturally out of rock materials or if it can be removed by pumping (in useful amounts), the rock materials are called aquifers.
Groundwater moves slowly, typically at rates of 7-60 centimeters (3-25 inches) per day in an aquifer. As a result, water could remain in an aquifer for hundreds or thousands of years. Groundwater is the source of about 40 percent of water used for public supplies and about 39 percent of water used for agriculture in the United States.
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Alaska Earthquake Rattles Florida’s Groundwater Plumbing
At 12:32 am Alaska time on January 23, 2018, a magnitude 7.9 earthquake shook Alaska residents out of their beds and set off fears of a tsunami all down the West Coast. Fortunately, the tsunami was only a few inches in height, but within an hour of the earthquake in Alaska, waves of a different sort were hitting far away in Florida.
The Quality of the Nation’s Groundwater: Progress on a National Survey
The U.S. Geological Survey is near the midpoint of a complex undertaking to survey the quality of the nation’s largest drinking-water resource.
Current website: https://www.usgs.gov/news/quality-nation-s-groundwater-progress-a-nation...
Study Estimates about 2.1 Million People using Wells High in Arsenic
Most Arsenic Presumed to be From Naturally Occurring Sources
High Levels of Radon Found in Some Wells Across Pennsylvania
A new U.S. Geological Survey study has discovered high levels of radon in wells across certain areas of Pennsylvania.
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!
Groundwater Quality in Eastern U.S.
A regional assessment of untreated groundwater in the combined Valley and Ridge and Piedmont and Blue Ridge aquifers in the eastern United States is now available from the U.S. Geological Survey.
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.
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.
High Plains Aquifer Groundwater Levels Continue to Decline
The U.S. Geological Survey has released a new report detailing changes of groundwater levels in the High Plains Aquifer. The report presents water-level change data in the aquifer for two separate periods: from 1950 – the time prior to significant groundwater irrigation development – to 2013, and 2011 to 2013.
Groundwater-Level Measurement near Jewel Cave National Monument, SD
USGS groundwater hydrologist, Bill Eldridge, is lowering a transducer into an observation well near Jewel Cave National Monument to monitor water-level changes in the Madison aquifer. The data collected will be used to update previously published groundwater-altitude maps to help better understand groundwater flow. The work is being conducted in cooperation with the
...Collecting groundwater quality sample
With property owner's permission, a USGS hydrologist collects a water sample from a private well in Gem County, Idaho
Measuring the groundwater level in a well near Lame Deer, Montana
Measuring the groundwater level in a well near Lame Deer, Montana
Potential Corrosivity of Untreated Groundwater in the United States
- Corrosive groundwater, if untreated, can dissolve lead and other metals from pipes.
- National maps have been prepared to identify the occurrence of potentially corrosive groundwater in the U.S.
- These findings have the greatest implication for the 44 million people dependent on domestic wells for drinking water.
Groundwater gage in Indiana
USGS scientist tests groundwater samples for water quality.
USGS scientist tests groundwater samples for water quality.
The USGS is near the midpoint of a complex undertaking to survey the quality of the nation’s largest drinking-water resource. From 2012 – 2023, the USGS is assessing groundwater throughout the country through extensive sampling. The latest results from five regional aquifers are now available.
Setting up Groundwater Streamgage on Green River nr LaBarge
Setting up Groundwater Streamgage on Green River nr LaBarge
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
Real-time Groundwater Streamgage equipment set up
Real-time Groundwater Streamgage equipment set up
Groundwater Monitoring
Data recorder in a field well shelter monitoring a well in New Jersey