SAN FRANCISCO (CBS SF) – A study of California beaches reveals that many of the dirtiest places to take a dip are right here in Northern California, though conditions at most of the region are better than in previous years.

Last week we learned that Santa Cruz’s Cowell Beach ranked as the dirtiest sand strip in the state, according to Heal the Bay’s annual survey of conditions. However, a closer look at the data shows far more Northern California spots on their “Beach Bummer” list than SoCal locations for the first time in recent years. The designation means that researchers recorded the lowest water quality during the year at those locations.

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Heal the Bay assigned A to F letter grades to the studied beaches and gave excellent marks for bacterial pollution levels to 92 percent of Bay Area ocean beaches. Only six of 28 bay beaches received a C or worse grade.

So which beaches failed the test? Here are the 7 Northern California beaches labeled among the 10 bummers, including their grade and overall rank (which for some reason don’t match exactly):

Santa Cruz Cowell Beach Most Polluted

( Commons)

1. COWELL BEACH – Santa Cruz CountyGrade F
Cowell makes the list for the fifth straight year for “chronic and persistent poor water quality.” You can’t state the eew factor any better than the study:

“The study revealed persistent low levels of human-associated fecal bacteria which led researchers to a buried pipe on the sand…the city of Santa Cruz traced the pipe to a toilet in a nearby apartment building.” Yuck. The city has since repaired the problem.

2. MARINA LAGOON – San Mateo County – Grade F
The second dirtiest beach in the state gets very little circulation from its body of water, a slough which feeds the San Francisco Bay. Maybe cross the Peninsula from Foster City and step into the ocean if you are looking to take a dip.

5. STILLWATER COVE – Monterey County – Grade D
This body of water last appeared on the list in 2004, but returned this year thanks to runoff from an adjacent storm drain likely sending shopping center sludge and golf course runoff onto the beach.

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6. CLAM BEACH COUNTY PARK – Humboldt County- Grade D
One of the most visually stunning beaches in Humboldt counties is also one of its dirtiest. Clam Beach is making its second trip to the bummer list this year. Researchers say bacteria is likely getting there from local sewage treatment systems and both wild animals and local pets.

Pillar Point Harbor

Pillar Point Harbor (Robert Campbell/US Army Corps of Engineers)

8. PILLAR POINT HARBOR – San Mateo County – Average Grade C
Researchers are still trying to determine why this body of water, right next to the legendary Mavericks Surfing spot, has high levels of “fecal indicator bacteria.” They say filtering storm-water and fixing leaking sewers systems are the next steps in cleaning up the harbor.

9. CAPITOLA BEACH – Santa Cruz County – Average Grade C but an F seasonally
South Bay sun-seekers flock to this Santa Cruz County spot, but so does bacteria. The beach has appeared on three of the last six bummer lists based on chronically low water quality. Fortunately, the H2O scores high during warm, dry parts of the year.

10. WINDSURFER CIRCLE – San Francisco County – Average Grade D but an F seasonally
If you were planning on jumping in the water just south of the Candlestick Park parking lot, think twice. During winter months this spot is an F for water quality. It’s also about the least appealing swim spot we can come up with. Just don’t.

Five San Mateo County beaches were named among the state’s cleanest. None of the other local counties had beaches that made that list.

For the full mostly-positive breakdown, and to get grades for all of the tested beaches, check out the full report.


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