On the shores of Playa del Rey sits L.A.’s last line of defense against sewage streaming into the Santa Monica Bay — and a jacked El Niño this winter threatens to be more than a match for it.
Built in 1950, the Hyperion Water Reclamation Plant handles roughly 95% of the city’s sewage on any given day — up to 800 million gallons of effluent from toilets, washing machines, sinks, industrial operations and more.
Storms can overwhelm the aging facility, which suffered an equipment breakdown in 2021 that led to a massive amount of raw sewage gushing into the Santa Monica Bay. Los Angeles officials are bracing for more trouble if the forecasted “super” El Niño brings heavy rains and flooding.
“We have done our best; a great job of maintaining it,” Joone Kim-Lopez, general manager of Los Angeles Sanitation and Environment, or LASAN, told the L.A. City Council recently. “But as with anything, this infrastructure needs attention.”
L.A.’s stormwater and wastewater systems are separate, but when it rains, water seeps into the ground and can sneak into the cracks of aging wastewater pipes, said Tracy Quinn, chief executive of environmental group Heal the Bay.
Storms can overwhelm the Hyperion plant, which suffered an equipment breakdown in 2021 that led to raw sewage gushing into the Santa Monica Bay.
(Jason Armond / Los Angeles Times)
This is how underground pipes can burst during heavy rains — or worse, how large wastewater plants like Hyperion can be overloaded and potentially spill into the ocean or back up sewage into homes and businesses, Quinn said.
Hyperion’s operators take the risk of heavy rainfall seriously, and add extra staff when extreme weather is forecast, according to Tonya Shelton, public information officer for LASAN. In addition, each year between April and October crews are testing generators, redundancy systems and other equipment to prepare for the worst, Shelton said.
“Ahead of the upcoming rainy season, LASAN is actively working to safeguard the public, our crews, and our critical infrastructure,” Shelton said in a statement to The Times.
Sanitation crews are also working to clear debris and shore up burn scar areas to mitigate flood risks, Mayor Karen Bass’ office said in a statement.
Hyperion failed in 2021 after human error and equipment failure flooded the plant. The spill was initially reported as 17 million gallons, although the Environmental Protection Agency later revised that to 12.5 million gallons. On a dry summer day, workers ran for their lives as a deluge of water knocked out pumps and electrical equipment.
Quinn, who served on the technical advisory committee that reviewed the 2021 spill, said the city made many of the suggested changes to better prepare for spills.
“This will be the first time that the system is truly tested with extreme storms, and it’s really going to depend on the ability of the staff that are working there to quickly address any issues,” she said.
For the record:
11:32 a.m. Oct. 2, 2026An earlier version of this story gave an incorrect title for Mark Gold. He is director of the California Cooperative Oceanic Fisheries Investigations program at UC San Diego’s Scripps Institution of Oceanography.
The 2021 spill was related to poor maintenance, not an overwhelming amount of rain, said Mark Gold, director of the California Cooperative Oceanic Fisheries Investigations program at UC San Diego’s Scripps Institution of Oceanography. It signaled a decades-long worsening of the city’s infrastructure.
“Sewers and water distribution systems are out of sight and out of mind, and so unless you have a major spill or some other sort of catastrophe, it often is difficult to prioritize infrastructure,” Gold said.
The city agreed to significantly raise sewer fees over four years starting in 2024, eventually doubling its rates, in order to fund additional repairs and sewer maintenance. Gold said the additional funds, while painful for residents, were sorely needed after more than a decade of no such increases.
Councilmember Eunisses Hernandez, who chairs the Public Works Committee, said in a call with The Times that improving and replacing aging pipes and other equipment at Hyperion is expensive. Nearly 30 other entities and municipalities — including Beverly Hills, Culver City and West Hollywood — rely on Hyperion to treat their sewage. Hernandez said the city may need to raise fees to those other entities instead of relying only on city ratepayers.
“It comes to getting these other jurisdictions to pay their fair share for using our infrastructure,” she said.
The city manages 6,700 miles of wastewater or sewage pipes — about the distance from L.A. to China, or enough to wrap around the moon — and 1,200 miles of stormwater pipes, which carry rainwater and other runoff straight into the ocean.
Of those pipes, around half are more than 50 years old, Kim-Lopez said. Around a third are more than 90 years old and are far past their expected life cycles.
Hyperion is the “granddaddy” of the four city facilities like it, Kim-Lopez said. It received major updates in the 1950s, and is the largest water reclamation plant of its kind west of the Mississippi River, according to LASAN.
