Good news for the coming summer months: Marin County beaches received solid grades from 2011 to 2012, according to a new report released last week.
The nonprofit group Heal the Bay analyzed weekly bacterial pollution from hundreds of beaches statewide, including 69 beaches in Marin, San Francisco, San Mateo, Alameda and Contra Costa counties.
Of those, 54 Bay Area beaches received "A" grades on the A-to-F scale based on levels of weekly bacterial pollution tracked from April to October of last year.
Bay Area beaches along the Pacific Ocean fared better in the ratings than ones along the Bay, with 98 percent of oceanside spots receiving "A" or "B" grades compared to 88 percent of bayside beaches, said Amanda Griesbach, a beach water quality scientist with Heal the Bay.
Of the Marin beaches, 87 percent earned A grades and 13 percent earned B grades during summer dry weather. Monitoring locations were not sampled during the winter, according to the report. The report stated that Marin County’s water quality monitoring program gathered data from 23 bayside and oceanside monitoring locations. Ocean locations included Dillon Beach, Bolinas Beach (Wharf Road), Stinson Beach, Muir Beach, Rodeo Beach and Baker Beach.
There was one sewage spill in Marin County that led to a beach closure this past year. Approximately 2,775 gallons of sewage was released on Feb. 7 near Schoonmaker Beach and resulted in the beach being closed for three days.
The group also released a "Beach Bummer List" of the top 10 most polluted beaches in California, and no Bay Area beaches were on this year's list.
Of the 10 beaches on that list, seven were in Los Angeles County and two were in Orange County.
Santa Cruz County's Cowell Beach, ranked second-most polluted, was closest on the list to the Bay Area.
Poor grades, such as Cowell Beach's "F," indicate that beachgoers face an increased risk of contracting illnesses — including the stomach flu, ear infections and skin rashes — compared to those visiting cleaner beaches.
Baker Beach at Lobos Creek, where a news conference was held today to announce the report's release, was No. 8 on last year's "Beach Bummer" list but has improved to a "B" grade this year, Griesbach said.
The worst marks received by Bay Area beaches were at San Mateo County bayside beaches that experience limited circulation, including Pillar Point Harbor, Oyster Point, Aquatic Park and Lakeshore Park, which received D's and F's for their summer conditions.
Beaches in Sonoma County all received A's, according to the report.
Griesbach, the report's lead author, said the excellent beach water quality in the Bay Area can be largely attributed to local water quality improvement efforts.
However, she said, "there continues to be disparity between wet and dry weather water quality, making it important for local agencies to maintain momentum towards implementing water quality improvement projects."
Eliet Henderson with the group SF Baykeeper explained that many of the problematic beaches become polluted during rainy weather, which can overwhelm sewage systems that then leak into the ocean.
Heal the Bay, which is based out of Los Angeles and is in its 27th year of operation, has issued the report cards for 22 consecutive years.
More information about the report card, which analyzed 441 beaches in California, can be found at Heal the Bay's website at www.healthebay.org.
— Bay City News Service