San Luis Obispo County environmental health officials are warning the public to stay out of the water around the Pismo Beach Pier because of high fecal bacteria levels that can cause illness.
Last week, water samples collected by county Environmental Health Services came back exceeding state health standards, said Jeremiah Damery, a county environmental health specialist in the beach-monitoring program. Samples are taken 14 yards south of the pier, and the advisory extends 50 yards north and south of the area where the samples are collected.
“It started last Monday and continued all week,” Damery said Monday. “We sampled again today and we will get the results Tuesday.”
High bacteria counts were once common south of the pier. It was so bad that in 2008 Cal Poly conducted a yearlong study using a $660,000 state grant to Pismo Beach.
The study attributed the problem to seagulls and pigeons roosting underneath the pier. Their many droppings landed on the beach, contaminating the water. Signs warning of bacterial contamination were posted at the beach 23 times in 2007 and 24 times in 2006.
The city of Pismo Beach took several steps to control the problem, including stringing nets beneath the pier to reduce the number of roosting birds. The steps seemed to be working, Damery said. The number of water samples exceeding acceptable state levels of bacteria dropped off.
Damery said he can’t explain the recent spike in contaminated samples.
“It may be just an unnatural spike, or the birds could still be causing the problem,” he said. “They are still there.”
County Environmental Health Services takes ocean water samples at 19 locations along the coast on a weekly basis. The sample locations range from San Simeon in the north to Oceano Dunes in the south.
Samples are analyzed for three types of indicator bacteria, which at sufficient concentrations indicate the potential presence of microbes that can cause human illness. Possible illnesses range from ear infections to the stomach flu.
The results are compared with standards established by the state. If any of the state standards are not met, a health advisory is issued. Such an advisory consists of signs warning bathers to avoid water contact activities because of the presence of elevated levels of bacteria.
Advisory signs remain posted until sample results indicate that bacteria levels meet state standards.