Ballona Creek and Sepulveda Channel Low-Flow Treatment Facilities

To reduce pollution and improve water quality before runoff reaches Santa Monica Bay, the Los Angeles Bureau of Engineering and LA Sanitation and Environment selected Kiewit Infrastructure West Co. to construct low-flow treatment facilities at Ballona Creek and Sepulveda Channel.  Located about seven miles apart, the facilities capture dry-weather flow and stormwater for treatment using ozone disinfection technology.

At Ballona Creek in Culver City, Kiewit rehabilitated components and systems at the existing North Outfall Treatment Facility. The team also constructed infrastructure to divert and treat flows from the nearly nine-mile channel, which serves a 55,000-acre drainage area. The Ballona pump station was designed for up to 29 million gallons per day (MGD), with up to 6 MGD treated through the ozone system and up to 23 MGD diverted to the Hyperion Water Reclamation Plant. Treated water is discharged back into Ballona Creek. Kiewit’s scope also included demolition of existing structures and construction of pump stations, diversion structures, overflow systems and maintenance buildings.

At Sepulveda Channel in Los Angeles, near Culver Boulevard, Kiewit constructed a system to divert, treat and return captured flow to the channel. The facility serves a drainage area of approximately 15,000 acres and was designed to treat up to 1.3 MGD.

Portions of the diversion structures were constructed during the April-to-October dry season because the work was located within the channels. The underground pump stations also required 50-foot concrete walls, with the Ballona crew completing the wall construction under budget through detailed planning and careful pour sequencing.

Once operational, the facilities will reduce bacteria and other pollutants entering local waterways while providing an additional source of reclaimed water for the city.