17 Million Gallons Of Raw Sewage Spills Into Pacific Ocean Closing Some L.A.-Area Beaches To Swimmers

Some Los Angeles-area beaches were closed to swimmers on Monday after 17 million gallons of untreated sewage spilled into the Pacific Ocean.

Sanitation officials said the Hyperion Water Reclamation Plant in Playa del Rey had become “inundated with overwhelming quantities of debris” after a power outage, triggering the plant’s relief system to discharge the waste matter through a pipe one mile offshore.Hyperion Executive Plant Manager Timeyin Dafeta said in a statement that the “emergency measure” was necessary “to prevent the plant from going completely offline and discharging much more raw sewage.” He added, “Normally the discharge of treated sewage is through the five-mile outfall.” According to the L.A. Times, “Dafeta said he believes that the incident was the largest amount of untreated sewage discharged through the one-mile pipe over the last 10 years,” and “the one-mile pipe was last used for a major discharge of wastewater in 2015.”

17 million gallons of sewage is about 6% of a daily load, Dafeta said.The L.A. County Department of Public Health issued a beach closure order on Monday affecting swim areas around Dockweiler State Beach and El Segundo Beach. They will remain closed until water samples are confirmed negative for elevated bacteria.

On Monday afternoon, L.A. County Supervisor Janice Hahn tweeted, “We are going to need answers about how and why this happened.”

“Protocols for notifying regulatory agencies and the State’s Office of Emergency Services were followed,” said Dafeta on Monday. “Water quality sampling and testing of shoreline (beach) samples are currently being conducted, and our monitoring vessel traveled to both outfalls to make observations and take samples for analyses following regulatory permit protocols.”

More details from the L.A. Times:

At about noon on Sunday, a large amount of debris unexpectedly clogged filtering screens with openings less than an inch in size at the treatment plant, said Barbara Romero, the director of L.A.’s Department of Sanitation and Environment.

The plant’s managers tried adding screens to replace the ones that were blocked. They also tried redirecting the flows to a storm drain system within the plant — an alternative way to bring the water through the normal treatment process.

But after several hours of recirculating the water, the system was still too overwhelmed…

So about 7:30 p.m., plant workers discharged the wastewater one mile out and 50 feet deep into the ocean. The normal process directs treated wastewater 190 feet down.

According to Romero, sanitation workers successfully routed the flows of water back through the standard treatment process around 4:30 a.m. on Monday.

Heal the Bay, an environmental nonprofit dedicated to protecting coastal waters of Greater L.A., warned that “bacteria and viruses in raw sewage are extremely dangerous to people and can carry a variety of diseases.”

The group posted information about the discharge on its website and urged people to stay out of Santa Monica Bay until further notice.

“Debris such as tampons and plastic trash, when released into the Bay, can harbor bacteria and can cause entanglement of wildlife, but it seems in this case that debris were successfully filtered out of the spill before it made it to the Bay.”