The Supreme Court on Tuesday threw out a water pollution lawsuit against Los Angeles County. The suit had been brought by environmentalists because of storm water runoff that had flowed into the Los Angeles and San Gabriel rivers after heavy rains.
But the 9-0 ruling did not deal with the larger question of regulating storm water runoff, and it left open the possibility that better monitoring in the future would limit this pollution in waters off Southern California.
The case decided Tuesday illustrated the difficulty of monitoring and controlling pollution that results from storm water that runs off city streets into drains and eventually into rivers and the ocean.
The Clean Water Act forbids “discharges” of pollutants into protected waters. Citing this law, the Natural Resources Defense Council and Santa Monica Baykeeper sued the Los Angeles County Flood Control District for allegedly violating its water-quality permit. The lawsuit cited high pollution readings in the county’s two monitoring stations, which sit in the rivers.
Last year, the U.S. 9th Circuit Court of Appeals ruled the county was liable for violating the law and referred to the polluted water flowing from the “concrete channels” into the natural part of the lower river as discharges of pollutants.
But in Tuesday’s decision, the Supreme Court said the 9th Circuit’s opinion rested on a mistaken premise. 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.”
