The Water Research Foundation Publishes Research to Inform California’s Direct Potable Reuse Regulations

Oct 20, 2021
Press Release

The Water Research Foundation announced the publication of research funded under a $1.4 Million Grant from the California State Water Resources Control Board (SWB) to advance protective practices for potable reuse. This research focuses on understanding and managing pathogen risks and chemical peaks in reuse applications. It will be used by the SWB’s Division of Drinking Water to develop direct potable reuse regulations in California by 2023 and ensure the protection of public health. The findings are also critical for utilities, regulators, and stakeholders across North America and around the world as the implementation of these sophisticated projects expands. These grant funds were supported by additional funding from key partners, including the Metropolitan Water District of Southern California (MWD). Learn more about WRF's SWB grant.

“These crucial research findings highlight California’s dedication to water supply resilience and WRF’s unique capabilities to manage and conduct timely research to protect public health,” said Peter Grevatt, CEO of The Water Research Foundation. “We are proud to provide this research to SWB so that they can ensure that California enacts the most appropriate regulations for direct potable reuse.”

Mike Markus, General Manager of Orange County Water District and WRF’s Board Chair, said, “This research will be extremely useful not only in California but throughout the United States as utilities look to expand the reliability and resiliency of their water supplies.”

"We are intimately connected to water; it is one of our most precious resources whose value increases in proportion to its purity. This research provides SWB key information for the development of direct potable reuse regulations to ensure the purity of water provided to the public,” said Robert Brownwood, Principal Engineer and Chief of SWB Department of Drinking Water’s Program Management Branch.

Final research findings from the following projects are now available:

Research under a larger grant ($3.1M) from the SWB and MWD ($700K) to advance potable and nonpotable reuse is still underway. The 20 projects are ongoing through 2023 and will help the state of CA and communities across the globe address technical and operational challenges with water reuse.

If you have questions about this research, please contact Julie Minton, WRF Research Unit Lead, at

About WRF

The Water Research Foundation (WRF) is the leading research organization advancing the science of all water to meet the evolving needs of its subscribers and the water sector. WRF is a nonprofit, educational organization that funds, manages, and publishes research on the technology, operation, and management of drinking water, wastewater, reuse, and stormwater systems—all in pursuit of ensuring water quality and improving water services to the public.