U.S. Supreme Court Rejects Ninth Circuit Determination That Moving Water Through A Conduit Is a "Discharge": Dam Operators Remain Safe From Clean Water Act Liability

January 9, 2013

In a short and unanimous ruling issued yesterday, the U.S. Supreme Court in Los Angeles County Flood Control District v. Natural Resources Defense Council (No. 11-460) rejected the Ninth Circuit's holding that a "discharge" of pollutants occurs when water is moved through a concrete flood control channel into a navigable river. As noted in our November 2 post, this is one of two cases of particular concern to dam operators on the Supreme Court's current docket. The Supreme Court's opinion reaffirms the long-standing doctrine that dams and other water control structures do not "discharge" pollution, the primary test of liability under the Clean Water Act ("CWA"), where those structures merely pass polluted water through the dam works without adding new pollutants. Operators of such facilities can now breath a sigh of relief because the Ninth Circuit's inroad into this doctrine has been eliminated.

The case arises from a citizen suit filed by environmental groups claiming that the L.A. County Flood Control District violated its Clean Water Act ("CWA") permit by allowing excessive levels of pollution in its municipal storm water control system. The District Court rejected the suit, concluding that the Flood Control District had not "discharged" a "pollutant" into the water so as to violate the CWA, but had only transported already-polluted water in the flood control channels, relying on the Supreme Court's holding in South Florida Water Management District v. Miccosukee Tribe. In that case, the Supreme Court held unanimously that no addition of a pollutant occurs that could trigger liability under the CWA when a conveyance merely transfers water from one part of a water body to another without adding any pollutants.

The Ninth Circuit's holding was so firmly at odds with Miccosukee. that not even the environmental plaintiffs attempted to defend the Ninth Circuit's decision in the Supreme Court, as discussed in our December 10 post. Rather, the environmental plaintiffs pressed an alternative theory of liability based on the specific provisions of the CWA governing storm water control. The Supreme Court did not address the plaintiffs' alternative theory, which will be tested on remand to the Ninth Circuit.

If you have any questions about the Supreme Court case discussed in this post, the regulation of dams, or other matters related to the utility industry, natural resources, water, or environmental law, please contact a member of GTH's Energy, Telecommunications and Utilities practice group or Environment & Natural Resources practice group.