Study indicates high levels of bacteria often found in mouth of San Luis Obispo Creek in Avila Beach

AVILA BEACH, Calif. -- Research conducted by the Surfrider Foundation indicates bacteria levels found at the mouth of San Luis Obispo Creek in Avila Beach often times exceeds state health standards.

"Here at the creek mouth, roughly 35% of the time the water flowing out into the creek into the ocean is contaminated with a level of bacteria that the state considers unsafe for human contact," said Niel Dilworth, Surfrider Foundation San Luis Obispo Blue Water Task Force Coordinator. "It varies up and down along the creek and on any particular week on whether some spots are high or low. Some spots are chronically higher, some tend to be lower, but it can occur all up and down along the creek."

The findings were released recently in Surfrider Foundation’s 2022 Clean Water Report, which determined 19% of water samples tested across the nation indicate high levels of bacteria that exceed water quality criteria. 

Dilworth said water samples are tested regularly by Surfrider Foundation volunteers, with those taken at eight different locations along the creek, including at the mouth as it empties into the Pacific Ocean.

"What we test for is enterococcus bacteria, which is the EPA's lead indicator for the presence of human waste," said Dilworth. "It's the same test the county uses and the City of San Luis Obispo uses, and we are finding routinely high levels that exceed state standards in this water behind me and along Avila Beach, and so that is a concern."

The mouth of the creek is a well-visited place for beachgoers to play in, especially for families who wish to stay away from ocean shoreline.

"It's shallow," said Dilworth. "It's warm. There's no waves. It's a very popular for people to bring their very young children, but it's also a place that's chronically high in bacteria, and that's a natural occurrence in any estuary, but we want people to be informed about how long should you let your kids be in the water, should you take precautions, should anybody who has an underlining health condition consider being more careful about being in the water because this water eventually ends up in the water at Avila Beach."

For those who may suffer from bacterial exposure, it may cause illness, with its severity depending on a person's health status.

"A typical exposure you may get mild illness, something like the flu, gastrointestinal events, fever, aches," said Dilworth. "However, if you are an especially young person or an older person or someone who has a compromised immune system, exposure to that bacteria can be much more life-threatening. It can be much more significant disease. We just don't want anybody to be exposed to that without their own knowledge that's what is  happening."

Knowing the water in the popular creek area may be high in bacteria is causing some visitors to the area to be concerned about possible exposure.

"Being a grandmother and a parent and having my kids grow up here, there's always a concern of safety and it is unfortunate that there are these higher counts that might cause adverse conditions or make it not as safe to play in," said Rosemarie Janowicz of Arroyo Grande. "I probably would take (family members) someplace else, but I know how much they love the beach, so it's kind of a tradeoff. If you come down here, they're going to go into the water."

According to the San Luis Obispo County Environmental Health Department, it regularly takes samples of the water at the mouth of the creek, which are posted at SurfSafeSLO.org.  

In a statement, the department said SurfSafeSLO also provides detailed sampling results for the past 30 days for this and all SLO County ocean water monitoring sites. The results for the last 30 days show that all sample results were below state standards for E. coli, total coliforms and enterococcus bacteria in ocean water, so no advisories were issued. 

The Environmental Health Department added it does not take samples of the nearby lagoon area, as opposed to the Surfrider Foundation.

The department's state mentioned enclosed waters such as lagoons often exceed water quality advisory levels because birds visit these areas and drop a lot of waste, and there is little flushing from/to the open ocean. The County has posted permanent water quality advisory signage to the bridge pylons adjacent to the Avila Lagoon. 

Dilworth pointed out Surfrider Foundation is hoping to determine the exact source of the bacteria can be determined with the with the goal of preventing contamination in the future.

"There is potentially multiple sources" said Dilworth. "We hope to see if we can do something about mitigating that, to work with the county, work with Environmental Health and other agencies to see if we can find out how to prevent that bacteria from getting into the water and winding up at the beach."