Report shows Linda Mar Beach in Pacifica contaminated with human waste; source still a mystery
At the unofficial start of summer during the Memorial Day weekend, Bay Area residents are likely to flock to the beach, including a popular Peninsula spot that has been plagued by chronic fecal bacteria contamination
For decades, the southernmost part of Linda Mar Beach along Highway 1 in Pacifica has tested high with dangerous levels of fecal bacteria. Now, tests have demonstrated that the bacteria in waters of San Pedro Creek, which empties into the ocean at Linda Mar Beach, come primarily from the human intestinal tract.
Pacifica resident John Keener a retired biochemist and geneticist, is the lead volunteer of the Linda Mar Water Quality Coalition, which provided CBS News Bay Area with the data. His team along with other volunteers sampled four sites along the creek, as well as a control site above the urban areas, and discovered the contamination comes from humans.
"It's about 30 to 40 times above the human health threshold," Keener said.
Linda Mar Beach, officially known as Pacifica State Beach, has suffered from the chronic problem for decades. Each year, the nonprofit Surfrider Foundation issues a report on the state of America's beaches, and once again, Linda Mar Beach landed in the top 10 list of beach bacteria hot spots.
"Seventy-two percent of the time ... It was above the human safety threshold," Surfrider regional manager Sara Heintzelman said.
Up to now, no one knew if the source of the contamination came from humans, wildlife, or domesticated animals or some combination. San Pedro Creek drains an eight-square mile watershed and flows through the San Pedro Valley and Pacifica's Linda Mar neighborhood before it reaches the southern end of the beach.
"We need to find what the main source is and that is what has been puzzling us really for decades," Pacifica Mayor Christine Boles told CBS News Bay Area.
Keener has an idea. The main suspect is orangeburg pipes, made from wood pulp and tar and used extensively in sewer laterals and sewer mains during the 1940s thorough the 1970s and now considered obsolete.
"This pipe is renowned for its leakiness," said Keener.
The City of Pacifica has already replaced miles of sewer mains and is also offering $2,000 to anyone who wants to replace their aging laterals. Sewer laterals connect a property's plumbing to the sewer main. Replacing a sewer lateral can be expensive.
"This is a high priority to the city to get this right," Boles said.
"It definitely won't get fixed overnight," added Heintzelman. But she said educating the community about how to stay safe along the coast, alerting them to real issues, and how to approach fixing the problem, are critical first steps.
The San Pedro Creek Watershed Coalition was formed in 1988 with representatives from water boards, Pacifica, San Mateo County, local residents, and scientists to investigate the chronic pollution. The renewed focus on cleaning up the contamination, at a time when the Trump administration proposes to cut money from the Federal Beach Act and the U.S. Environmental Protection Agency, are thanks to scores of volunteers, environmentalists, residents, researchers, and surfers.
People planning on visiting Linda Mar Beach this weekend are urged to pay attention to warning signs are at the southern end of the beach, and enjoy the beach north of the landmark Taco Bell Cantina. The advice is especially critical during the rainy season.
