Downpours Yield 33 Billion Gallons of Captured Stormwater in L.A. County

County officials hope reclamation efforts will help the region reduce its dependence on imported water supplies.

1 minute read

January 19, 2023, 12:00 PM PST

By Diana Ionescu @aworkoffiction


View of Los Angeles River at Glendale Narrows segment with tree and overpass

The Los Angeles River swelled after heavy rains in early January. | Gerry Matthews / Los Angeles River

Los Angeles County captured 33 billion gallons of stormwater from the recent rains that drenched California, an amount that “could supply 816,000 people with water for a year,” reports Carlos Granda for ABC7. As Granda explains, “The county Public Works Department operates 14 major dams and 620 miles of rivers and flood control channels.”

One way the county collects rainwater during storms is through a series of ‘Valley Rubber Dams’ on the San Gabriel River, which can be inflated to hold water when needed. Water is then distributed to spreading facilities designed to let water soak into the earth to replenish groundwater supplies. “Approximately 98% of stormwater runoff collected from the San Gabriel River and Rio Hondo Channel is conserved, according to officials.”

Local officials plan to boost stormwater retention and use more local water supplies to reduce dependence on imported water. Southern California has historically drawn water from the state’s Owens Valley, the Colorado River, and other sources such as Mono Lake, where a conservation nonprofit recently requested a suspension of water diversion to Los Angeles to protect the lake’s critical Califoprnia gull habitat.

Tuesday, January 17, 2023 in ABC7

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