National Water-Quality Assessment (NAWQA) Program

   Home    Headlines    Featured Studies    Liaison Committee    Informing Decision Makers    Data    Modeling/Software    Publications    Maps

Featured Studies
National-Synthesis Assessments
Pesticides
Nutrients
Volatile Organic Compounds
Ecology
Trace Elements
Regional Assessments on Water-Quality Status and Trends
Streams and rivers
Ground water
Water Quality in NAWQA Study Units
Study Unit listing and reports
Topical Studies of National Water-Quality Priorities
Effects of urbanization on stream ecosystems
Transport of contaminants to public-supply wells
Sources, transport, and fate of agricultural chemicals
Mercury in stream ecosystems
Effects of nutrient enrichment on stream ecosystems
Special studies on source-water and drinking-water quality
Surface-water intakes
Public supply wells
Domestic wells
Trends
Water
Sediment
General Information
About the Program
Glossary
Related Sites
Contact us

NAWQA's 19 Principal Aquifer Assessments

Larger Map (GIF)

  1. Basin and Range basin-fill and carbonate-rock aquifers
  2. Biscayne aquifer
  3. California Coastal Basin aquifers
  4. Cambrian-Ordovician aquifer system
  5. Central Valley aquifer system
  6. Coastal Lowlands aquifer system
  7. Columbia Plateau basin-fill and basaltic-rock aquifers
  8. Denver Basin aquifer system
  9. Edwards-Trinity aquifer system
  10. Floridan aquifer system and overlying Surficial aquifer system
  11. Glacial aquifer system
  12. Hawaiian volcanic-rock aquifers
  13. High Plains aquifer system
  14. Mississippi Embayment - Texas Coastal Uplands aquifer system
  15. New England crystalline-rock aquifers
  16. Northern Atlantic Coastal Plain aquifer system
  17. Piedmont and Blue Ridge crystalline and carbonate-rock aquifers
  18. Rio Grande aquifer system
  19. Snake River Plain basin-fill and basaltic-rock aquifers
  20. Valley and Ridge and Valley and Ridge carbonate-rock aquifers

Regional contacts

Regional Assessments of Principal Aquifers

A major focus of the NAWQA Program in its second decade (2002-2013) is on regional- and national-scale assessments of ground-water status and trends in principal aquifers. The U.S. Geological Survey Office of Ground Water has identified 62 principal aquifers in the U.S. (U.S. Geological Survey, 2003,). About 1/3 of the Nation's principal aquifers are the focus of water-quality assessments at the principal-aquifer scale by NAWQA. (see listing on right side)

The NAWQA framework for principal aquifer assessments considers the physical setting of the aquifer, in addition to its susceptibility and vulnerability to contamination.

More information about Principal Aquifer Assessments (USGS Fact Sheet 2005-3013, PDF)

Publications about Principal Aquifer Assessments

Selected issues addressed by NAWQA's ground-water status and trends assessment

What is a Principal Aquifer?

Principal Aquifer Map

Definition: A principal aquifer is defined as a regionally extensive aquifer or aquifer system that has the potential to be used as a source of potable water. An aquifer is a geologic formation, a group of formations, or a part of a formation that contains sufficient saturated permeable material to yield significant quantities of water to wells and springs. Aquifers are often combined into aquifer systems. (U.S. Geological Survey, 2003).

More Information

 

Accessibility FOIA Privacy Policies and Notices

Take Pride in America home page. FirstGov button U.S. Department of the Interior | U.S. Geological Survey
URL: http://water.usgs.gov/nawqa/studies/praq/index.html
Page Contact Information: nawqa_whq@usgs.gov
Page Last Modified: Wednesday, 12-Nov-2008 10:30:52 EST