California to add recycled sewer water to the state reservoirs

Millerton Lake, on top of California’s Friant Dam in Friant. On Tuesday California regulators adopted new rules to supplement the state’s 36 reservoirs with recycled water. (REUTERS/Lucy Nicholson)

California’s water regulation agency approved new measures Tuesday that will allow recycled water – water that once ran through the sewers – to be added to the state’s reservoirs, The San Francisco Chronicle reported.

The new rules are expected to be implemented by 2023.

"This is a type of indirect potable use — it's not treated recycle water that goes directly to someone's house," said Miryam Barajas at the Water Board. "It's highly treated."

She says the new regulations could potentially affect all 36 of California’s reservoirs that serve as the main source of the state’s municipal drinking water.

The regulations are the result of a two-year public review process in which an expert panel decided that the regulations were necessary for public health and to supplement existing drinking water supplies with recycled water.

San Diego is at the forefront of a sewer-to-reservoir operation that the rest of the state will likely follow.

The board is working to implement “direct potable reuse” – a process by which treated recycled water is added directly into a drinking water system.