(CN) - The Los Angeles County stormwater drainage system dumped excessive amounts of bacteria and other pollutants into the Santa Monica Bay and areas along the Malibu coastline, a federal judge in Los Angeles ruled in a partial victory for two environmental groups.
U.S. District Judge A. Howard Matz granted summary judgment to the Natural Resources Defense Council and Santa Monica Baykeeper on their claims over excessive bacteria at the Surfrider Beach in Santa Monica Bay and along a four-mile stretch of coastline from Malibu to Ventura.
But the judge dismissed the groups' technical claim that the county and the Los Angeles Flood Control District failed to properly submit compliance reports with the permits.
The dispute centers on the operation of the municipal separate storm sewer system, known as MS4, in the Los Angeles County basin. MS4 carries runoff from local storm drains to inland rivers, and this runoff eventually makes its way to the Pacific Ocean. MS4 includes storm drains operated by 84 incorporated cities, and includes thousands of miles of storm drainage pipes and "hundreds of thousands" of connections.
The discharge of this runoff is permitted by the Regional Water Quality Control Board, a state entity that issued a National Pollutant Discharge Elimination System permit required under the Clean Water Act.
The permit allows the discharge of stormwater runoff except where such discharge causes or contributes to a violation of water-quality standards or water-quality objectives.
It also contains a monitoring requirement, requiring that water-quality samples be taken five times per week at Surfrider Beach. This monitoring has revealed that bacteria levels at the beach have exceeded federal standards "dozens of times" in the summer months since 2006, the ruling states.
Further monitoring requirements have revealed that the Los Angeles River and San Gabriel River have tested for excessively high levels of pollutants such as aluminum, copper, cyanide, zinc and fecal coliform bacteria.
In response to these findings, the NRDC and the Santa Monica Baykeeper filed suit against Los Angeles County, the Los Angeles Flood Control District, and certain individual county supervisors. They said the defendants have violated the permit's limits on certain discharges into the waters of Southern California, and have thus violated the Clean Water Act.
The parties filed cross-motions for summary judgment, and Judge Matz granted relief to both sides.
However, he sided with neither party on the claim that the county's storm sewer system illegally dumped pollutants into the Santa Clara River, Los Angeles River, San Gabriel River and Malibu Creek watersheds.
Because the monitoring stations for these rivers and creeks are downstream from where the storm drains link to the larger MS4, the defendants argued that it was impossible to pinpoint the source of excessive pollutants.
"[N]either side has introduced evidence of whether the standards-exceeding pollutants passed through the defendants' outflows," Judge Matz wrote.
He ruled for the plaintiffs on their Surfrider Beach and Malibu coastal region claims, for the defendants on most of the compliance report claim and asked both parties to submit more evidence on the watershed claims.
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