SAN DIEGO— The city of San Diego is well-known for its beautiful weather and diverse culture, but its crown jewel may be the beaches that line the coast from Imperial Beach to Oceanside.
That’s why it’s concerning when beaches are often subject to health warnings and even closures as sewage and water runoff contaminate the water making it dangerous for swimmers and surfers.
San Diegans are likely familiar with the beach closures that come following rainstorms. Water runoff during storms runs across the pavement and concrete that line San Diego’s coastline and sweeps along oil, sewage, and other pollutants that are found on streets and walkways.
Logan Simone, a surfer in San Diego for 11 years, understands that the closures are necessary, despite the inconvenience.
“Obviously we don’t like it as surfers,” Simone said. “But I do see when it rains and Mexican has oil spills and all the sewage runs off, it does affect the wildlife and ends up over here.”
Dong, another local San Diego surfer said surfers notice a difference in the water quality following storms.
“You can tell,” he said. “I’ve had a couple of buddies get sick after surfing a day after runoffs. You can see what looks like oil streaks on the top of the water and depending on the sun angle, you’ll see reflections with different colors over the water.”
The most impacted area in San Diego County is Imperial Beach. Due to its positioning just across the Mexico-United States border, sewage from Mexico is constantly flowing north and polluting San Diego beaches. According to the California Water Board, there have been 58 beach closures in San Diego Country in 2022 as of Nov. 20. The cause of 48 of these closures was determined to be associated with sewage or grease from the Tijuana River.
This has led to organizations such as the Surfrider Foundation, a foundation that combats beach and ocean pollution to develop programs to find solutions for the border sewage issue.
“I think last year it was 50 million gallons per day of raw sewage getting sent right into the Pacific,” Surfrider’s San Diego Chapter Manager Alex Ferron said. “That sewage is such a prevalent part of ocean life in southern San Diego and Tijuana.”
Last year Surfrider was able to help persuade the Environmental Protection Agency to allocate $300 million to a solution on the border, something that according to Ferron, took years of litigation and writing campaigns.
While the border issue has been more problematic than other areas in San Diego, a new study conducted by San Diego State University, has discovered sewage issues can be found north of the border as well.
Led by Environmental Engineering Professor Natalie Mladenov, a team of researchers went out to “understand the sources of microbial pollution of the San Diego River during storm events.” The river runs through the heart of Mission Valley.
“We have a range of issues in the San Diego River watershed that could be blamed for this microbial pollution of the San Diego River,” Mladenov said. “Those sources include such things as illegal discharges to storm sewers, illegal connections, leaky sewer lines, sanitary sewer lines, and sanitary sewer overflows. Another somewhat contentious issue is the waste associated with homeless encampments.”
Using auto-samplers, the team collected samples from the San Diego River and two tributaries after storm events over the course of two years to analyze the microbial and bacterial data.
“We determined that all the evidence was pointing towards sanitary sewer lines as the main source of pollution and not so much those other sources,” Mladenov said. “The largest magnitude of pollution was coming from wastewater that was recently in sewer pipes, not aged feces that had been sitting out in the open.”
By comparing samples from the river water during storms to the river on a calm day, the scientists found that both caffeine levels and certain bacteria levels were much higher during storms. According to Mladenov, caffeine, and bacteria like the one that spiked, are short-lived in the natural environment.
“The presence of those two, in particular, was an indication that we have some sources that are very, very fresh and the concentrations were very high,” she said. “This can only be explained by the presence of wastewater.”
Until these leaky pipes are repaired, the problem will continue to worsen as they deteriorate over time.
For environmentalists, the thought of leaky sewer pipes sending sewage out into San Diego’s oceans is a startling one— especially as beach closures continue to increase. According to the California Water Board, the number of beach closures in San Diego Country due to sewage has increased each year in the last three years, 28 in 2020, 44 in 2021, and 58 as of Nov. 20, 2022.
Lucero Sanchez, campaigns manager for San Diego Coastkeeper, an organization dedicated to finding solutions to environmental issues said that San Diegans looking to help find a solution should turn to those with the power to make a change.
“I think the biggest one for me that I like to remind people is you have elected representatives that are there to represent you,” Sanchez said. “It could be as easy as emailing a representative and saying, ‘Hey I live in your district. I care about clean water, please do something about the pollution in our area.’”
Ferron also stressed the importance of voting on the city level.
“The best thing anyone can do is to pay attention to what’s happening in your city,” Ferron said. “You’re voting, you’re showing up at the city level and you’re advocating for what you want to see.”