A sewage line on the verge of being replaced in Carson, California, collapsed last week, sending around 8.5 million gallons of raw sewage into storm drains—more than twice the amount of initial estimates given by Los Angeles County officials. The sewage then made its way to the Dominguez Channel, a 15.7-mile stretch of river that runs from Hawthorne to the San Pedro Bay and the Pacific Ocean as part of the Dominguez Watershed. This has led to the closure of seven beaches as officials work to decontaminate them. Beaches will reopen once water testing can confirm that bacterial levels do not pose a threat to beachgoers. There is no estimated date for when beaches will reopen.
The Los Angeles County Sanitation Districts responded last Thursday night to reports of sewage spilling from a manhole onto an intersection in Carson and eventually installed eight bypass pipes and pumps to contain the spill. The emergency system sends sewage flowing through pipes located around the collapsed section and to a nearby manhole where it rejoins the main sewage line. Officials believe the collapse was due to sulfuric acid degrading the concrete pipe. Sulfuric acid is a naturally occurring byproduct of decomposition from organic material. Officials also believe the pipe was further stressed from an influx of rain last week. Los Angeles County was showered with up to nine inches of rain the week prior to the pipe collapse. The deluge broke multiple records for the area, including daily rainfall records in the San Fernando Valley and Antelope Valley.
According to a 2020 research project conducted by scientists at UCLA, incidents of extreme precipitation are expected to increase with climate change. “It’s currently thought the character of precipitation will probably change, with more intense atmospheric rivers and longer dry spells between them. In other words, California’s already variable climate may become even more extreme,” researchers noted. This presents a major threat to some of Los Angeles County’s aging infrastructure. An investigation into the pipe collapse is underway but some officials believe much more should be done.
“We really have to investigate further. This is an older sewer. This is installed in the 1960s. We have a program to monitor the condition of the sewers in our system,” Los Angeles County Sanitation District Manager Bryan Langpap told CBS Los Angeles. “This is something that we knew was near the end of its life.” According to the Los Angeles Times, the collapsed sewer line was nearing the end of its use and would’ve been redirected to a new sewer main within a year. Many sections of Los Angeles County’s sewer system, which serves more than 5 million people, are up for replacement and renewal, according to a list of current projects. One such project, the Figueroa Street and Yosemite Drive plan, will repair more than 5.5 miles of sewage lines. It was originally scheduled to finish in the spring of 2019.
Given the rapid decline of the sewage pipe that led to this major spill, it’s abundantly clear that Los Angeles County cannot delay its plans for repairs and replacements any further, especially given the environmental impact of sewage spills. Hazardous spills are already so common in the area that a major wastewater spill from earlier last year is already being researched by UCLA scientists. A wastewater backup at the Hyperion Water Reclamation Plant led to flooding at the plant and 17 million gallons of raw sewage flowing into Santa Monica Bay. Debris clogged drains, which led to the flooding, which is still under investigation. The county’s Environmental Monitoring Division believes it could take a year or longer to fully understand the long-term impact of the spill. The Hyperion Water Reclamation Plant is the oldest and largest in Los Angeles, having been in operation since 1894.
One of the best ways to tackle aging infrastructures’ failings and better adapt to climate change is through bold investments. Tell lawmakers to pass the Build Back Better Act to prevent environmental disasters like what’s happening in Southern California.
This article has been updated to reflect that Los Angeles recorded up to nine inches of rain in some areas, and not nine feet.