Ninety-one percent of California beaches received high marks for water quality this summer but Los Angeles County beaches continue to face troubling water quality during the high-traffic summer season, according to Heal the Bay’s 2008 End of Summer Beach Report Card and four local beaches got D or F grades.

The Santa-Monica based environmental group assigns an A to F letter grade to beaches along the California coast every summer, based on levels of bacterial pollution reported from Memorial Day weekend through Labor Day weekend.

The Beach Report Card is based on the routine monitoring of beaches from Humboldt County to the Mexican border by local health agencies and dischargers. Water samples are analyzed for bacteria that indicate pollution from various sources. The better the grade a beach receives, the lower the risk of illness to ocean users.

Some 91 percent of the 514 beaches tracked statewide by Heal the Bay received A or B grades this summer, an indication of excellent or very good water quality. Those marks are essentially even with last summer, when 92 percent of sites received good grades.

In Los Angeles County, the state’s most populated region, nearly one out of five beaches tracked received F grades — 21 out of 109 sites monitored this summer, according to the report card.

Water quality dropped at Santa Monica Bay beaches this summer as well, with 86 percent of 63 monitored beaches receiving A or B grades, compared to 93 percent last year. Among the Santa Monica Bay beaches receiving D or F grades this summer are Venice Beach at Topsail Street on the Marina Peninsula, Dockweiler State Beach at Ballona Creek in Playa del Rey and Santa Monica beaches at the Santa Monica Pier and at Wilshire Boulevard.

Malibu’s Surfrider Beach, Paradise Cove, Solstice Canyon at Dan Blocker Beach and Marie Canyon at Puerco Beach were among other county beaches to receive D or F marks in the report.

If Los Angeles County beaches are removed from the grading curve, state water quality marks improve dramatically, Heal the Bay officials note. Nearly 97 percent of the 405 beaches outside the county earned A and B grades, with only six locations receiving failing grades.

A second summer of drought this year contributed to positive results statewide because the dry conditions limited the amount of urban runoff, the biggest source of ocean pollution, according to Heal the Bay. Infrastructure enhancements, funded by the state’s $100 million Clean Beach Initiative, have also led to improved marks at dozens of chronically dirty beaches.

But Heal the Bay officials noted that ocean users are now facing increased health risks after ongoing funding for Assembly Bill (AB) 411 implementation was removed in a line item veto in the recently-approved state budget.

For ten years, beachgoers have been protected by AB 411, a state law that created public-health bacteria standards and monitoring requirements for ocean water quality at California’s public beaches during the high-traffic summer season, officials said.

Water quality monitoring in the state’s 15 coastal counties stands to be eliminated or severely curtailed because of the nearly $1 million cutback, said Mark Gold, Heal the Bay president.