Beach fecal contamination is not being caused by any activity at Pillar Point Harbor but rather from upland sources, according to a recently released study by the San Mateo County Resource Conservation District.
Though the report revealed no smoking gun, it did rule out decades of sometimes contentious assumptions about the cause — from dogs on beaches to sewer leaks at the harbor north of Half Moon Bay.
“One of the significant findings of our study is the high counts of bacteria are landscape issues. Bacteria is not coming from the harbor, activities in the harbor or even because the harbor doesn’t flush. It’s noteworthy that it’s coming from behavior and sources upland,” said Kellyx Nelson, executive director of the San Mateo County Resource Conservation District. “So people need to make a better connection between their activities upland and the effects on water quality in the harbor.”
The primary focus of the study was Capistrano Beach, which the State Water Resources Control Board identified as significantly impaired. The county Environmental Health Division has also permanently posted it with potential health warnings and it is on the Save the Bay’s list as one of the most impaired beaches in Northern California, Nelson said. The RCD study also examined five other harbor beaches as well as the live-aboard harbor boats.
The San Mateo County Harbor District, which oversees both Pillar Point and Oyster Point Marina Park in South San Francisco, contributed $15,000 to the multi-year study.
“The harbor is kind of a victim in this sort of thing, because the stuff doesn’t originate there it’s not caused, according to the study, by activity in the harbor,” said Peter Grenell, general manager of the San Mateo County Harbor District.
People have known about the high levels of bacteria at Pillar Point beaches for years and various hypotheses as to who or what was to blame was a polarizing community issue for decades, Nelson said.
“We were concerned that although there were a number of theories, there hadn’t been any science done to test those hypotheses and determine what might be the source. And furthermore, we were concerned that people might feel obligated in expending significant resources in trying to address one of the hypotheses without a good likelihood that the money spent would actually address the real problem,” Nelson said.
Even though the RCD study didn’t identify a smoking gun, it was valuable as it ruled out unfounded theories, Nelson said.
Neither harbor birds nor canines on the beach are of cause so efforts to prohibit dog walking would be moot. The bacteria isn’t from human feces, so theories about leaky sewer lines or live-aboard boat waste are unfounded, Nelson said.
Discovering the contamination wasn’t from human feces went a long way to assuage fears about severe public health concerns, said Dean Peterson, the county’s environmental health director. The main source of pollution came from wildlife sources and bacteria or viruses found in animals that aren’t typically contagious to humans, Peterson said.
The study found a major pollutant was bovine feces contaminating Deer Creek, but that creek doesn’t run into Capistrano Beach so it’s not an encompassing explanation, Nelson said. And while the study doesn’t pinpoint the original source of bacteria but that it’s from uphill activity, the RCD can now go about establishing effective recommendations, Nelson said.
Controlling wildlife fecal input into the storm drain system is not feasible so the focus is now on changing human behavior and cleaning the water before it reaches the beaches, Nelson said.
The RCD will continue to develop suggestions and mitigation efforts including public outreach and education, effective uses of planting vegetative buffers, ways to clean storm water and drains before it reaches the beaches and further water quality monitoring, Nelson said.
The Harbor District has no jurisdiction or control over residential behavior upland in nearby El Granada but it is continuing to ensure Pillar Point behavior doesn’t contribute to the fecal pollution, Grenell said.
The RCD has trained several members of the Pillar Point Harbor Patrol now taking samples of water in the boat basin and contributing them for further study, Grenell said.
Both Grenell and Peterson agree the RCD has a strong track record of working with private individuals and public entities. A major component of resolving the problem will be educating and working with landowners to change how they manage animal waste and behavior, Peterson said.
“It’s a matter of continuing education,” Peterson said. “We really need people to understand what goes into the storm drain is going to be affecting the harbor and eventually the Pacific Ocean.”
(650) 344-5200 ext. 106