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New study shows Imperial Beach ocean pollution worse than previously thought

In Imperial Beach, the holiday weekend ended with another round of beach closures. KPBS border reporter Gustavo Solis has an update on the other crisis at the border — cross-border sewage pollution.

The current north swell is bringing big waves to San Diego and Imperial Beach Mayor Serge Dedina has been taking full advantage.

“Every surfer on the coast knows we’ve had one of the most epic swells in a year,” he said. “Just perfect surf everywhere.”

Dedina has recently surfed in Ensenada, La Jolla and Sunset Cliffs. But not Imperial Beach. In fact, cross-border water pollution has kept Dedina away from his hometown surf break for more than two years.


“I got so sick,” he said. “I’ve had two ear surgeries, two sinus surgeries, I just can’t afford to get sick anymore.”

And now a recent study by the Scripps Institution of Oceanography at UC San Diego shows that the water might actually be even more polluted than we thought.

RELATED: County Environmental Health extends water contact closure to Imperial Beach

The study came about because researcher Falk Feddersen kept hearing Imperial Beach surfers say that the water smells funny even when water tests showed it was safe to swim.

What would happen is the surfers would say 'hey … water tastes like laundry detergent or chemical or sometimes like sewage,'” Feddersen said.


The source of this pollution is Punta Bandera, a place six miles south of the U.S. border where sewage from a nearby treatment plant is dumped into the ocean. South swells push that pollution north toward Imperial Beach.

San Diego County determines pollution levels by measuring the amount of a specific bacteria known as fecal indicators like E. coli in the ocean water.

“That bacteria dies very quickly in sunlight,” Feddersen said. “So it takes like a day and a half to two days for the flow to get from Punta Bandera to IB. If it's exposed to sunlight in that period of time the microbes they are testing for have died.”

But viruses like the norovirus, which the county doesn’t test for, do survive the journey. And they make people sick.

While it is relatively easy and inexpensive to test for fecal indicators, testing for the other types of bacteria getting through requires special equipment, Fedderson said.

In most circumstances, the county’s testing efforts are sufficient. But Imperial Beach is in a unique situation because it is so close to the border, attracts a lot of people and has strong currents.

“Nowhere in the United States is raw sewage at these levels just dumped into the ocean and not a lot of places where you get lots of swimmer and wave driven currents that are so fast,” Fedderson said. “The county is doing the best it can.”

New study shows Imperial Beach ocean pollution worse than previously thought

Scientists from the Environmental Protection Agency helped conduct Scripps Institution study.

This research could guide the agency as it decides how to spend hundreds of millions of dollars on infrastructure projects along the border to address cross-border sewage pollution.

RELATED: Federal climate scientists say 2021 was sixth warmest year on record

The goal of those projects is to stop pollution from multiple sources – like Punta Bandera as well as the Tijuana River Valley.

Dedina said he is optimistic.

“Despite the closures and the ongoing pollution crisis, we do have some progress on the policy and planning front,” he said. “The EPA director Michael Regan announced a $600 million plan – a comprehensive solution that would involve fixing the river flows, the canyon flows and what’s coming out on the beach.

Imperial Beach isn’t just for people who live there. Its waves attract surfers from all over the southern part of San Diego. John Bashong lives in Chula Vista but surfs Imperial Beach almost every day – as long as the water is clean, he said.

“For those of us who live south of (State Route) 54 this is our local break,” he said.

The one silver lining from the pollution is that it keeps the break from getting too crowded, he joked.

“When we go for long periods without a sewage contamination day the crowds build and build and build,” Bashong said. “Then the signs will go up and everybody leaves.”

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