The City of Los Angeles Department of Public Works will soon break ground on the $13 million Low Flow Diversion Project in an effort to improve the water quality in the Los Angeles River and Arroyo Seco.
The project is led by global design firm Stantec’s Pasadena office and is in collaboration with Los Angeles Department of Public Works Bureau of Engineering and Los Angeles Sanitation & Environment. It will provide new infrastructure to remove dry-weather flows from five sub-watersheds to the LA River and Arroyo Seco.
The LA River and the Arroyo Seco are negatively impacted by multiple pollutants contained in dry-weather flows. Heavy metals and petroleum products are also washed into storm drains and waterways. Dry-weather flows are usually a combination of runoff from car washing, lawn sprinkling, and watering of plants or gardens.
Diverting the dry-weather flows from the storm drains into existing sanitary sewers and to the City’s Hyperion Water Reclamation Plant for treatment benefits in two ways. The first is improvement to the water quality of the LA River and Arroyo Seco. The second provides additional water that, once treated, can bolster water security in the region.
“The City of Los Angeles wants to use Arroyo Seco and the LA River for more recreational purposes,” said Venu Kolli, Stantec senior principal and project manager. “It’s critical that the water quality is improved. Diverting this low-flow water is an excellent way to enhance the waterways and give the City additional resources through water reclamation. We are excited to see the community-enhancement project start construction.”
The completed project should divert about 1 million gallons per day from storm drains, while providing no negative impact on wet-weather flows from storms. The project is led by Clarke Contracting Corporation for Los Angeles River Low Flow Diversion projects and Mike Pirch and Sons for Arroyo Seco Low Flow Diversion projects.
Construction is expected to be completed by November 2022.