With a historic drought showing no signs of letting up, the city of Los Angeles is drafting a new plan to use more local water sources by capturing storm water throughout the L.A. basin. At recent community meetings, officials from the Department of Water and Power (along with the city's Sanitation Department) have been showcasing potential ideas for the final plan, due out this summer.
This new plan would make storm water about 4 percent of the city's annual water budget. For the first time, LA is talking about making storm water a small but reliable part of the city’s water sources – 25,000 acre-feet, or somewhat over 8 billion gallons of storm water a year. For perspective, a typical one-inch rain event in Los Angeles County produces more than 10 billion gallons of storm water, most of which hits asphalt and concrete, flows into storm drains and goes to the sea.
On top of that, Los Angeles Mayor Eric Garcetti issued an executive order last October, directing the LADWP to cut its purchase of imported water in half within a decade, in part by cutting water consumption at least 20 percent.
LA could invest in much-larger-scale versions of those ideas. Good places for those bigger projects tend to be in the San Fernando Valley, where the geology is hospitable to rain water capture and the city has clearest rights.
Some examples featured in the LADWP’s presentation aren’t yet approved, but are in consideration:
- Water capture and storage at the Van Norman Complex;
- The Canterbury Power Line Easement, running between the Tujunga Spreading Grounds and the Pacoima Wash, which would capture 1500 acre-feet of water a year; and
- Converting Strathern Park (near the Hollywood Freeway) from a disused gravel pit/landfill to a wetlands park, in joint operation with L.A. County.
Storing storm water in the ground means protecting some areas from industrial pollution, and means filtering and treating polluted groundwater as it’s pulled from aquifers. Last November’s $7.5 billion dollar water bond earmarked funds for storm water capture and for groundwater cleanup. DWP officials say they’re hoping to bring some of that money to Los Angeles.