Beach bummer: San Mateo’s Marina Lagoon makes top 10 worst water quality list

San Mateo’s Marina Lagoon, specifically Aquatic and Lakeshore parks, received a near year-round “F” — making it the No. 4 spot on Heal the Bay’s Top 10 Beach Bummers list.

“We do [these report cards] because we recognize the need to protect swimmer health and monitor a number of locations throughout the West Coast to prevent illness among swimmers, surfers, all people who use the ocean recreationally,” said Heal the Bay Spokesman Nick Colin.

Santa Cruz’s Cowell Beach ranked the worst in the state and San Francisco’s Candlestick Point came in seventh, according to the report. Pillar Point Harbor, which has long been plagued by bacteria infested water, showed improvement over the last year by receiving only one F during wet weather conditions, according to the report.

On Wednesday, warning signs were posted to deter swimmers at the Marina Lagoon and at the ocean-side beaches of Pillar Point as well as Fitzgerald Marine Reserve, according to the San Mateo County Health System.

The closures and poor grades are based on concentrations of E. coli and enterococcus — bacteria that can cause gastrointestinal and respiratory illnesses that could range from minor infections to fatalities, Colin said.

Despite the warning signs, children still swam at San Mateo’s Aquatic Park where city officials are working to address the water that’s exacerbated by poor circulation. The city spends nearly $200,000 annually on specialists to manage nuisance plant growth and has recently begun to clean up animal droppings, said Deputy Public Works Director Gary DeJesus. Based on recent tests, the water quality is improving as the city tries a more multi-faceted approach to dealing with the marina that gathers stormwater runoff, DeJesus said.

“The reason it’s improving is because we’ve developed for the first time a Marina Lagoon Management Plan that includes aquatic vegetation control as well as clean up of the water fowl droppings,” DeJesus said. “We’re committed to maintaining the highest water quality feasibly possible.”

The city also uses pumps to help circulate the water and changing tides contribute as well, DeJesus said.

The lagoon is impacted by stormwater runoff, of which there has been little since the drought. Although residents throughout the state are struggling with the unusually dry conditions, it appears it may be having a positive impact on water quality at certain beaches.

“Our extended drought is a double-edge sword. Obviously we’re dying of thirst, but the upside, if you can call it that, is improved water quality due to a lack of pollutants and toxins reaching these water bodies,” Colin said.

Various beaches in and around Pillar Point Harbor on the coastside are contaminated by high bacteria levels frequently attributed to stormwater runoff, particularly during the winter. The harbor ranked eighth worst in the state last year, but has since dropped off the list.

“It’s good news that [Pillar Point Harbor] did not make the top 10 list of the most polluted beaches this year,” Nicole David, vice president of the San Mateo County Harbor District Board of Commissioners, wrote in an email. “Many beaches have seen some water quality improvements because they have received less runoff due to the drought conditions. However, the water quality data collected by San Mateo County on a weekly basis still show regular exceedances for indicator bacteria” at beaches around the harbor.

David, a marine biologist, said it’s important the Harbor District continue to work with those monitoring the water quality of the harbor — such as county health officials, the Surfrider Foundation and the county’s Resource Conservation District — to determine possible sources of the bacteria.

While the annual report is meant to highlight poor conditions and educate the public, Colin said the nonprofit also seeks to help determine ways to deter dangerous bacteria.

“Heal the Bay is not interested in just pointing the finger and saying ‘clean this up.’” Colin said. “We’re actively engaged with these communities to find solutions to these problems.”

samantha@smdailyjournal.com

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