Heavy rains overtaxed county sewer systems in January, causing water quality to plummet in the Santa Monica Bay, according to a local environmental group.
In its January beach report card, Heal the Bay gave an F grade to 27 of 61 locations along the Santa Monica Bay during rainy periods.
For the first time in the group's 13-year history, grades in dry weather were as poor as the grades in wet weather, with 20 beaches receiving F grades and an unprecedented 36 beaches receiving a C grade or lower for the entire month, said Heal the Bay Director Mark Gold.
"The huge volumes of polluted storm water contaminated most of the Santa Monica Bay beaches," he said.
The Department of Health Services recommends that beach-goers avoid contact with ocean water for three days after a rainstorm.
Heal the Bay's statistics are based on daily and weekly water quality monitoring data gathered by Santa Monica's Environmental Monitoring Division and the county's Department of Health Services and Sanitation Districts. The samples are tested for bacteria such as fecal coliform, which indicate biological pollution.
Beaches are graded on an A-F scale, based on risk of illness from water contact.
