CEC Drinking Water Resources

Public Water System CEC Information and Resources

Sample data of public water systems for CECs, specifically for PFAS, is available to view and download using the Water Board’s GeoTracker PFAS Mapping Tool. Additional information is provided on the Water Board’s PFAS website for Drinking Water Resources.

California testing data in public water supply systems is available at the State Water Board’s Public Drinking Water Watch website.

As required by the 1996 Safe Drinking Water Act (SDWA) amendments, the USEPA is required once every five years to collect data for contaminants that are suspected to be present in drinking water and do not have health-based standards set under the SDWA.  A list of no more than 30 unregulated contaminants are tested for by public water systems. During the third (UCMR3) round occurring from 2013-2015 and the fourth (UCMR4) round occurring in 2018-2020, over 10,000 samples were collected in California for CECs. View Additional information about the UCMR sampling rounds and the occurrence data. Sample collection under UCMR 5 will be from January 2023 through December 2025. It will include the required sampling for 29 PFAS compounds and lithium at public water systems.

Current USEPA analytical methods for the analysis of CECs in drinking water are:

Water Boards SOPs

Indirect Potable Reuse (IPR) is the planned use of recycled water to replenish drinking water supplies with a suitable environmental barrier. There are two types of IPR projects: Groundwater Replenishment Reuse Projects (GRRP) and Surface Water Source Augmentation Projects (SWSAP). More information is provided here (DW Recycled Water IP | California State Water Resources Control Board)

Direct Potable Reuse is the planned introduction of recycled water either directly into a public drinking water system, or into a raw water supply immediately upstream of a drinking water treatment plant. More information is provided here (Regulating Direct Potable Reuse in California | California State Water Resources Control Board)


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Contact Us

If you have questions about our program, please email us at:

DWQ-Emergingcontaminants@Waterboards.ca.gov