SAN FRANCISCO (KCBS) – Bacteria levels at beaches all over the Bay Area have improved dramatically since last year, so beach goers can enjoy the shore without worry this summer, environmentalists said Thursday.

No beach in the Bay Area made the Beach Bummer list at the top of Heal the Bay’s annual Beach Report Card (.pdf) this year, in part because aggressive efforts to eliminate sources of water pollution throughout the region, said Amanda Greisbach, a water quality scientist with the organization.

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“There have been lots of water quality improvement projects, infrastructure projects that have been going on, diversion projects that may have helped,” she said.

KCBS’ Anna Duckworth Reports:

Twenty Bay Area cities have committed to upgrading and modernizing old drainage pipes in order to prevent rainwater sewage spills, said Eliet Henderson with San Francisco Baykeeper.

“Recreation doesn’t stop here in the winter. And those wet weather sewage spills are threatening the health of those recreational users,” Henderson said.

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Forty-two of 43 beaches between Marin and San Mateo counties received A or B grades during the summer dry weather period, including Baker Beach in San Francisco, which ranked eighth last year on the list of most polluted beaches, according to Greisbach.

“This year Baker Beach at Lobos Creek earned A and B grades during all three grading periods,” she said.

Every year, Heal the Bay samples bacteria levels at 650 beaches throughout California to assess both wet weather and dry weather conditions.

This year, five of the 10 worst beaches were in Malibu. Avalon Beach on Catalina Island ranked the worst.

Cowell Beach in Santa Cruz was number two on the 2012 Beach Bummer list.

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