Los Angeles County got a reprieve in an ongoing dispute over who is responsible for pollution from storm water when the U.S. Supreme Court on Tuesday overturned a ruling won by environmentalists.

However, the court’s 9-0 decision did not deal with the larger question of how to regulate storm water and urban runoff flowing into the region’s waterways.

Gary Hildebrand, assistant deputy director of the county’s Department of Public Works, said the court’s decision “validates the approach the flood control district has been taking to deal with water management.”

The ruling allows the district to move forward with updated storm water regulations that the regional water board put in place in November, he said.


The Natural Resources Defense Council and Santa Monica Baykeeper -- now Los Angeles Waterkeeper -- sued the flood control district in 2008 alleging that it had violated its storm water permit.

The lawsuit cited high pollution readings at monitoring stations in the county’s rivers.

Last year, the U.S. 9th Circuit Court of Appeals ruled that the county was liable for pollution in the Los Angeles and San Gabriel rivers, and referred to the water flowing from the “concrete channels” into the natural part of the lower river as discharges of pollutants.

The Supreme Court said the 9th Circuit’s opinion rested on a mistaken premise and reversed it.


The water flowing from one “concrete” section of the river to another section cannot be deemed a “discharge” of pollutants, the court said. Justice Ruth Bader Ginsburg said “no pollutants are ‘added’ to a water body when water is merely transferred between different portions of that body.”

Steve Fleischli, water program director and senior attorney with the National Resources Defense Council, said the question that the court decided was never in dispute between the parties. He called the ruling a “temporary setback” in efforts to hold the county accountable.

“It doesn’t close the door on our enforcement efforts against the county, and it doesn’t limit the county’s obligation to comply with the Clean Water Act,” he said.

County officials have also argued that the flood control district is not primarily to blame for the pollution in the rivers, because there are dozens of cities discharging polluted runoff upstream from the monitoring sites.


With only one monitoring station in each river, it is difficult to find the original source of the pollution.

The Supreme Court did not weigh in on that point, but when the case was argued last month, the justices commented that the county needs a better means of monitoring storm water runoff.

In her opinion, Ginsburg noted that the renewed storm water permit put in place by the Los Angeles regional water board will include monitoring the water quality at “discharge points” where storm drains flow into the rivers, which will provide more localized data.

Hildebrand said the ruling will not have an impact on a parcel fee the county is pursuing to raise about $290 million a year for projects that would help clean up storm water pollution. A hearing on that proposal is set for Jan. 15, and the Board of Supervisors may vote then to place the proposed fee on the ballot.


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abby.sewell@latimes.com

david.savage@latimes.com

Sewell reported from Los Angeles and Savage from Washington, D.C.