It's not a new phenomenon. Sewage from Baja California's faulty wastewater system has often drained into coastal waters and contaminated the shores of San Diego. What is new is the ability to accurately test coastal waters for bacteria and viruses.
Testing with a new DNA-based water-quality system began on May 5, 2022 and the results show far more pollution than previously measured.
According to Heather Buonomo, Director of the Department of Environmental Health and Quality, "This method is more accurate, more precise, so we’re able to get a better picture of what the water quality truly is."
Test results showed dangerously high levels of bacteria and viruses, which forced the closure of San Diego's southern beaches, from Imperial Beach all the way up to Coronado, home to one of America's most popular beachside resorts and training station for U.S. Navy SEALs.
Health officials warn that anyone who ignores the restrictions is putting themselves at risk for diarrhea, fever, respiratory disease, meningitis and even paralysis.
Coronado and Imperial Beach have been closed for weeks, and its likely that the closure will continue for months.
Buonomo said, “Until the root cause of this issue is addressed, which is correcting the sewage contamination that’s flowing up to these beaches, this will continue."
In addition to sewage spills, UCSD Scripps Institute of Oceanography and Stanford University have also identified Tijuana's Antonio de los Buenos sewage treatment plant as a major contributor to the problem, dumping an estimated 35 million gallons of raw sewage into the Pacific Ocean every day.
A $630 million plan has been proposed by the EPA to stop the cross-border pollution.
San Diego County is the first coastal community in the U.S. to begin using the DNA-based system. The new system took almost ten years to develop and was a collaborative effort between the U.S. Environmental Protection Agency, the California Department of Health, and UC San Diego researchers.