From sewage to sip: California adopts new water reuse rules
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Illustration: Sarah Grillo/Axios
California this week made large strides in recycling wastewater — yes, that's toilet water — into drinking water.
The big picture: The move is meant to make the Golden State more resilient to hotter and drier conditions amid a climate crisis that has led to multiple droughts, severely depleting water resources even after a series of atmospheric rivers that hit California last season.
Driving the news: The State Water Resources Control Board approved regulations Tuesday to allow the development of treatment protocols to convert wastewater into high-quality drinking water.
- The recycling process, known as direct potable reuse, enables water systems across the state to generate a climate-resilient water source while also reducing the amount of wastewater discharged to rivers and the ocean.
- The method is not a requirement but rather an option for local water authorities.
- Only the largest water systems will initially be able to invest in a treatment system, as they can cost $1 billion or more, board spokesperson Blair Robertson told Axios.
Of note: Some parts of California already treat wastewater to drinking water quality standards in a method called indirect potable reuse, which uses an environmental buffer like a lake or groundwater aquifer before treating the water.
- The method adopted this week does not require such a buffer and rather takes the treated water and distributes it directly to the public water system. The treatment requirements are also stricter.
Why it matters: This gives the nation's most populous state the most advanced standards in the country for treating wastewater — so much so that the finished product will meet or exceed current drinking water standards, per the board.
- It also adds millions of gallons of additional drinking water to the state's supply over time, while avoiding costlier and more energy-intensive ways to collect water.
Zoom out: Climate change is expected to produce more severe droughts in California and other places, and more weather whiplash events, per Axios' Andrew Freedman.
- A changing climate is a key factor in worsening the longest drought the state has seen for at least 1,200 years.
What they're saying: "This is an exciting development in the state's ongoing efforts to find innovative solutions to the challenges of extreme weather driven by climate change," E. Joaquin Esquivel, chair of the State Water Board, said in a statement.
- He said the reuse method will not only help build drought-resilient water supplies, it also offers energy savings and environmental benefits.
- "Most importantly," Esquivel added, "these regulations ensure that the water produced is not only safe, but purer than many drinking water sources we now rely on."
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