Water Science School

Groundwater

Groundwater is one of our most valuable resources—even though you probably never see it or even realize it is there. There is water somewhere beneath your feet no matter where on Earth you live. Groundwater starts as precipitation, just as surface water does, and once water penetrates the ground, it continues moving, sometimes quickly and sometimes very slowly. Eventually groundwater emerges back to the surface and continues to participate in the global water cycle.

All Groundwater Science Topics

All Groundwater Science Topics

View a list of all of our science topics about groundwater.

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Groundwater and the water cycle

Groundwater and the water cycle

Large amounts of water are stored in the ground. The water is still moving, possibly very slowly, and it is a part of the water cycle.

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Filter Total Items: 34
Date published: June 8, 2018
Status: Completed

Pesticides in Groundwater

Commercial pesticide applicators, farmers, and homeowners apply about 1 billion pounds of pesticides annually to agricultural land, non-crop land, and urban areas throughout the United States. The use of pesticides has helped to make the United States the largest producer of food in the world and has provided other benefits, but has also been accompanied by concerns about their potential...

Contacts: Ask USGS
Date published: June 6, 2018
Status: Completed

Contamination of Groundwater

Groundwater will normally look clear and clean because the ground naturally filters out particulate matter. But did you know that natural and human-induced chemicals can be found in groundwater even if appears to be clean? Below is a list of some contaminants that can occur in groundwater.

Contacts: Ask USGS
Date published: June 6, 2018
Status: Completed

Rivers Contain Groundwater

Naturally, the water running in rivers comes from precipitation that runs off the landscape into the river. But since precipitation also seeps into (and moves) into the ground, you don't often consider that a significant amount of the water flowing in rivers comes from water in the ground seeping back "up" into the river from below. 

Contacts: Ask USGS
Attribution: Water Resources
Date published: June 6, 2018
Status: Completed

Groundwater Wells

Wells are extremely important to all societies. In many places wells provide a reliable and ample supply of water for home uses, irrigation, and industries. Where surface water is scarce, such as in deserts, people couldn't survive and thrive without groundwater, and people use wells to get at underground water.

Contacts: Ask USGS
Attribution: Water Resources
Date published: June 6, 2018
Status: Completed

Artesian Water and Artesian Wells

Artesian water is really not different from other groundwater, except for the fact that it flows to the land surface because pressure in the rocks underground force it to the surface. But, having water flow to the surface naturally is a handy way to tap groundwater resources.

Contacts: Ask USGS
Attribution: Water Resources
Date published: June 6, 2018
Status: Completed

Contamination in U.S. Private Wells

Groundwater is crutial to millions of Americans as well as many more worldwide. Groundwater provides drinking water to many. Thus, having reliably clean groundwater is of concern for many throughout the world. But, groundwater can become contaminated with chemicals, biologic organisms, and other possibly-harmful agents.

Contacts: Ask USGS
Date published: June 6, 2018
Status: Completed

Groundwater Decline and Depletion

Groundwater is a valuable resource both in the United States and throughout the world. Groundwater depletion, a term often defined as long-term water-level declines caused by sustained groundwater pumping, is a key issue associated with groundwater use. Many areas of the United States are experiencing groundwater depletion.

Contacts: Ask USGS
Date published: June 6, 2018
Status: Completed

Drought and Groundwater Levels

Groundwater decline is a real and serious problem in many places of the Nation and the world. When rainfall is less than normal for several weeks, months, or years, the flow of streams and rivers declines, water levels in lakes and reservoirs fall, and the depth to water in wells increases.

Contacts: Ask USGS
Attribution: Water Resources
Date published: June 6, 2018
Status: Completed

Water Dowsing

"Water dowsing" refers in general to the practice of using a forked stick, rod, pendulum, or similar device to locate underground water, minerals, or other hidden or lost substances, and has been a subject of discussion and controversy for hundreds, if not thousands, of years.

Contacts: Ask USGS
Attribution: Water Resources
Date published: June 5, 2018
Status: Completed

Land Subsidence

Yes, land subsidence is responsible for you getting a little dizzy when you look at the first picture in the banner above, the one of a line of buildings. The land these buildings sit on has fallen and compacted because large amounts of groundwater have been withdrawn from the aquifers below ground. Land subsidence is a human-induced event.

Contacts: Ask USGS