Quality of Groundwater Used for Domestic Supply in the Northern San Joaquin Valley, California

Fact Sheet 2021-3040
Prepared in cooperation with the California State Water Resources Control Board
By: , and 



Groundwater provides more than 40 percent of California’s drinking water. To protect this vital resource, the State of California created the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The Priority Basin Project (PBP) of the GAMA Program provides a comprehensive assessment of the State’s groundwater quality and provides increased public access to groundwater-quality information. Private domestic and small-system drinking-water wells in the Northern San Joaquin Valley (NSJV) were the target for this assessment. These wells tend to pump water from shallower parts of alluvial aquifers compared to deeper, long-screened public-supply wells in the region.

Suggested Citation

Levy, Z.F., Balkan, M., and Shelton, J.L., 2021, Quality of groundwater used for domestic supply in the northern San Joaquin Valley, California: U.S. Geological Survey Fact Sheet 2021-3040, 4 p., https://doi.org/10.3133/fs20213040.

ISSN: 2327-6932 (online)

ISSN: 2327-6916 (print)

Study Area

Publication type Report
Publication Subtype USGS Numbered Series
Title Quality of groundwater used for domestic supply in the northern San Joaquin Valley, California
Series title Fact Sheet
Series number 2021-3040
DOI 10.3133/fs20213040
Year Published 2021
Language English
Publisher U.S. Geological Survey
Publisher location Reston, VA
Contributing office(s) California Water Science Center
Description 4 p.
Country United States
State California
Other Geospatial Northern San Joaquin Valley
Online Only (Y/N) N
Google Analytic Metrics Metrics page
Additional publication details