Malibu's coastline is considered the Riviera of California, but the celebrity-studded city's famed beaches are often among the most dangerously fouled in the state. Over the years, officials have blamed the primordial stew of surf contamination on a variety of causes: storm runoff, a wastewater treatment plant, horse manure, bird droppings.
But officials also suspect that some of the septic tanks that handle the household sewage of Malibu's multimillion-dollar canyon homes are spilling pollutants into the oak-shaded creeks that tumble down to Santa Monica Bay, tainting Surfrider and other famous beaches. At the urging of Los Angeles County Supervisor Zev Yaroslavsky, officials have begun trying to identify the sources of the fecal matter and other waste — using a novel approach borrowed from law enforcement.
The county plans soon to begin using DNA testing of sea water off Escondido and Ramirez canyons. The goal will first be to discern whether the waste is human or animal. Officials say they then plan to follow the trail wherever it leads, even if that means to the backyards and horse stables of well-heeled beachside and canyon residents. Officials say they are developing a testing method and plan to begin taking samples this fall, first from the ocean and then farther upstream as needed.
Other possible sources, they note, are restaurants and commercial facilities. The Paradise Cove mobile home park, for example, is upgrading its septic system after officials found that it was polluting the water off that private beach at the foot of Ramirez Canyon. "What we intend to do is look at specific locations where counts have been high and, with the permission of property owners, take samples from the streambeds behind their homes," said Mark Pestrella, assistant deputy director of the county's Department of Public Works.
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http://www.latimes.com/news/science/environment/la-me-malibu5oct05,1,651099.story