Los Angeles County Making Progress in Stormwater Capture

During this “super year” of storms, L.A. County has successfully captured 96 billion gallons of stormwater which is enough to meet the needs of about 2.4 million people a year.

2 minute read

May 20, 2024, 11:00 AM PDT

By Clement Lau


Water flowing through Glendale Narrows section of Los Angeles River in Glendale, California with a concrete bridge, power lines, and hills in background.

Water flowing through flood control channel in Glendale, near Los Angeles. | GDMatthews / Adobe Stock

Los Angeles County has managed to capture and store a significant amount of stormwater brought forth by heavy rains this winter and spring which sent torrential flows down local creeks and rivers. Specifically, an estimated 295,000 acre-feet of water since last October or 96.3 billion gallons was captured. This is sufficient to meet the water needs of approximately 2.4 million people a year, which is almost one-fourth of the county’s population of ten million residents.

As reported by Ian James, the county, working in coordination and collaboration with the Los Angeles Department of Water and Power and other agencies, was able to capture and store this amount of water thanks in part to investments totaling over $1 billion since 2001. Some of the funding has been used to raise dams and increase the capacity of spreading grounds, where water is sent into basins and then percolates underground into aquifers.

The county has also spent more than $1 billion since 2001 to remove sediment from reservoirs to ensure their water-catching capacity is not limited or diminished. A large portion of the funds have come from the L.A. County Flood Control District, which receives revenues through property taxes. Funding for stormwater-catching infrastructure is also generated through the Safe, Clean Water Program, which was established after county voters passed Measure W in 2018.

Though the amount of runoff captured since October has been substantial, the county’s facilities took in more water during the major storms over the previous 12 months — an estimated 626,000 acre-feet, which is enough to supply about five million residents for a year.

To learn more, please read the source article.

Saturday, May 11, 2024 in Los Angeles Times

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