Which areas in the United States are most dependent on groundwater?

Groundwater use is highest in parts of the country with limited rainfall but high water needs, especially for irrigation. Most of these areas are in the western half of the country, where annual rainfall is typically much lower than in the East and where surface water supplies cannot meet the demand for water.

In 2015, groundwater provided 29% of the total freshwater used in the United States. However, eight states and at least one territory depended on groundwater for at least 50% of their freshwater supply:¹

The states that use the largest total volumes of groundwater tend to have large populations and/or extensive farmland in arid areas. In 2015, just five states accounted for 54% of national groundwater use, mostly for irrigation:¹

References

¹ Estimated Use of Water in the United States in 2015 U.S. Geological Survey

Learn More:

• Estimated Use of Water in the United States in 2010 (Report), U.S. Geological Survey
  2014 report on the sources and uses of water in the U.S. in 2010 (the U.S. Geological Survey collects data on national water use every 5 years)

• USGS Groundwater Information Pages (Website), U.S. Geological Survey
  USGS portal for a wide variety of groundwater information

• Ground-Water Availability in the United States (Report), U.S. Geological Survey
  2008 report assessing national availability of groundwater. Written for a wide audience of people interested in management, protection, and sustainable use of U.S. water resources

• Ground Water Atlas of the United States (Book/Website), U.S. Geological Survey
  2000 atlas showing and describing the principal aquifers across the United States, including hydrologic and geologic information

• Trends in Water Use in the United States, 1950-2010 (Website), U.S. Geological Survey
  USGS webpage on how water use in the U.S. changed from 1950 to 2010

• Managed Aquifer Recharge (Factsheet), American Geosciences Institute
  Introduction to managed aquifer recharge, including how it works and its effects on water quality and availability

• Desalination as a Source of Fresh Water (Webinar), American Geosciences Institute
  Webinar on the use and desalination of salty water, including brackish groundwater, in the United States and further afield.