Groundwater, Aquifers, Wells, and Springs

This list of national principal aquifer codes and names are fixed values assigned by the National Water Information System (NWIS). Aquifers are identified by a geohydrologic unit code - a three-digit number related to the age of the formation, followed by a 4 or 5 character abbreviation for the geologic unit or aquifer name.

Declining snow cover is playing a key role in decreasing the flow of the Colorado River, “the lifeblood of the Southwest,” by enabling increased evaporation. As the warming continues, increasingly severe water shortages are expected.

USGS water-related projects of international interest.

As the USGS Water Resources Mission Area looks to the future, we are updating our water programs to meet 21st century water-resource challenges. As part of these updates, we are integrating the National Water Quality Assessment Project's water-resource monitoring, assessment, trends, modeling, and forecasting activities into new WMA programs.

For 43 years, the Shingobee Headwaters Aquatic Ecosystems Project (SHAEP) brought together scientists from the USGS along with students and professors from universities in Minnesota, North Dakota, Wisconsin, and California to study the physical, chemical, and biological processes of lakes, wetlands, and streams at local and watershed scales. In early 2022, The University of Minnesota and Bemidji...

The Urban Waters Federal Partnership reconnects urban communities with their waterways by improving coordination among federal agencies, particularly those impacted by pollution or economic distress.

Naegleria fowleri ( N. fowleri) commonly referred to as the "brain-eating amoeba", is a thermophilic free-living amoeba found in warm and hot surface water that include freshwater ponds, lakes, rivers, and hot springs (Yoder and others. 2010).

The USGS is evaluating the integration of small unoccupied aircraft systems – sUAS or "drones" – into USGS hydrogeophysical studies.

Our surface water, groundwater, and aquatic ecosystems are priceless resources, used by people across the Nation for drinking, irrigation, industry, and recreation. The National Water-Quality Assessment (NAWQA) Project is a leading source of scientific data and knowledge for development of science-based policies and management strategies to improve and protect our water resources.

Reliable drinking water is vital for the health and safety of all Americans. The USGS monitors and assesses the quality of the water used as a source for our nation's drinking water needs.

Wherever you live, there’s a creek or stream near you. The eighty percent of Americans who live in metropolitan areas are often unaware of the network of urban creeks—many teeming with life—that weaves through our cities and town. Nowhere are the environmental changes associated with urban development more evident than in urban streams.

From chloride to corrosivity, from pesticides to PAHs, find the most recent National Water Quality Program (NWQP) science on these topics and effects on surface water, groundwater, and ecology. Informative web pages provide an overview and links to related web pages, publications, maps, news, and data.