Groundwater quality in the Sacramento Metropolitan Shallow Aquifer, California

Open-File Report 2019-1047
Prepared in cooperation with the California State Water Resources Control Board



The Sacramento metropolitan (SacMetro) study unit covers approximately 3,250 square kilometers of the Central Valley along the eastern edge of the northern and southern ends of the San Joaquin and Sacramento Valleys, respectively. Groundwater withdrawals supply a significant portion of the water-resource needs of the region. In the southern portion of the study unit, groundwater accounts for nearly 90 percent of water demand in the area (South Area Water Council, 2011).

Groundwater sampled in the SacMetro study unit comes from alluvial aquifers primarily composed of sediments derived from the Sierra Nevada Mountains to the east. Recharge to the groundwater system is primarily from the streams draining the Sierra Nevada, and from precipitation and infiltration of applied irrigation water (California Department of Water Resources, 2003). The public-supply aquifer system assessments of this area in 2005 found elevated concentrations of inorganic constituents including arsenic, iron, and manganese as well as of solvents in some wells (Bennett and others, 2010; 2011).

This study was designed to provide a statistically representative assessment of the quality of groundwater resources used for domestic drinking water in the SacMetro study unit. A complete listing of what was measured, including the sampling results, are presented in Bennett and others, 2019. A total of 49 wells were sampled between July 2017 and November 2017 (Bennett and others, 2019). The wells in the study were 32–160 meters deep, and water levels were 1–62 meters below land surface.

Suggested Citation

Bennett, G.L. V, 2019, Groundwater quality in the Sacramento Metropolitan shallow aquifer, California: U.S. Geological Survey Open-File Report 2019–1047, 4 p.,

ISSN: 2331-1258 (online)

Study Area

Publication type Report
Publication Subtype USGS Numbered Series
Title Groundwater quality in the Sacramento Metropolitan shallow aquifer, California
Series title Open-File Report
Series number 2019-1047
DOI 10.3133/ofr20191047
Year Published 2019
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 Sacramento Metropolitan Shallow Aquifer
Google Analytic Metrics Metrics page
Additional publication details