Untreated Sewage Spill Prompts Closure Of Some L.A. Beaches

LOS ANGELES, CA — Seventeen gallons of untreated sewage spilled into the ocean prompting the closure of a stretch of beaches in Los Angeles County, officials said Monday. A power outage at the Hyperion Treatment Plant spurred the sewage spill on Sunday night, Los Angeles County Supervisor Janice Hahn said.

Beaches from El Segundo to the Dockweiler RV Park were closed to swimmers, Monday afternoon. It was not clear when they would reopen.

Hyperion Executive Plant Manager Timeyin Dafeta issued a statement Monday afternoon saying that on Sunday afternoon, the plant "became inundated with overwhelming quantities of debris, causing backup of the headworks facilities. The plant's relief system was triggered and sewage flows were controlled through use of the plant's one-mile outfall and discharge of untreated sewage into Santa Monica Bay."

Dafeta said the 17 million gallons of sewage — about 6 percent of a daily load — were discharged as an emergency measure through the one-mile outfall to prevent the plant from going offline and discharging more raw sewage. Normally, treated sewage is discharged through the five-mile outfall.

"Thanks to these efforts, and significant equipment improvements that have been made in recent years in partnership with several environmental groups, the amount of flow into the ocean was mitigated and the plant remained online," Dafeta said.

"These improvements included the reconfiguring of in-plant storm basins to pump sewage back into the plant in cases of emergency; screens were installed on all catch basins to prevent untreated debris from entering the storm drains and out to the ocean; and a Headworks Bypass had been installed to prevent raw sewage overflowing out of the Headworks building and into the street," Dafeta said.

The plant manager said the LA Sanitation & Environment department is following protocols for notifying regulatory agencies and the California Officer of Emergency Services about the spill.

The treatment plant, located in Playa Del Rey, is the biggest of its kind in the L.A. area and is among the largest wastewater processing facilities in the world.

No other details were immediately available.

A power outage at the Hyperion plant last night caused untreated sewage to be discharged into the ocean. Water samples are being tested and I'm getting more information about the scope of the problem.
Beaches from El Segundo to the Dockweiler RV Park are closed for swimming.
— Janice Hahn (@SupJaniceHahn) July 12, 2021