DPR: A Resilient Water Supply for California’s Future 

Emerging Issues

Great news – on December 19th, State Water Board approved the DPR regulations. California water associations applaud new rules with a unified, one voice >

Jennifer West, WateReuse California

Jennifer West, WateReuse California

We are living in a hotter, drier California. 2020 is on track to be one of the hottest on record. Seven of the ten most destructive wildfires in California’s history have burned in the last five years.  And, California has only recently emerged from one of the worst droughtin 500 years.   

Direct Potable Reuse (DPR) is a source of local supply to help blunt the impacts of climate change and create more than 1 million AFY of new water supply for California. For Southern Californiathis is the equivalent of a new major aqueduct. How did we get here? It didn’t happen overnight and it took a great deal of state and local leadership.  

California’s regulatory agencies first permitted groundwater potable reuse in 1962 (Montebello Forebay). Decades later, the Orange County Water District (OCWD) began successfully purifying wastewater through a multi-barrier treatment process and demonstrating the great potential of this “new” supply to replenish local groundwater basins and help droughtproof the regionExtensive monitoring and testing proved that potable reuse met or exceeded drinking water standards. OCWD’s renowned public outreach program and demonstration facility also showed that when communities understand the purification process, they will accept and actively support potable reuse programs.   

Major regulatory progress in California began with the adoption of statewide regulations for groundwater augmentation by the State Water Resources Control Board (Water Board) in 2014. Now, there are 19 planned potable reuse groundwater projects in the state. In 2017, the Water Board adopted regulations for Reservoir Water Augmentation — using highly purified recycled water to augment drinking water reservoirs.   

Also in 2017, the California Legislature kept the state on the path to DPR when it passed AB 574 (Quirk).  This legislation requires that – once six critical research projects are complete, the Water Board will adopt regulations for Raw Water Augmentation “DPR” by 2023.  Currently, the Water Board is beginning the process to assemble an Expert Panel to review this research and develop regulations for both forms of DPR (Raw Water Augmentation and Treated Drinking Water Augmentation).  Last summer, Governor Gavin Newson’s Water Resilience Portfolio stated that completing DPR regulations is priority action in moving California to a sustainable water future.  I am very proud that WateReuse California and our members have been on the forefront of all these efforts.   

Preparing the state for climate change is a huge challenge that will continue to require leadership, innovation, and political will at all levels.  

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