On October 28, 2024, the NAM filed an amicus brief urging the U.S. Supreme Court to address whether the Clean Water Act’s citizen-suit provision allows private citizens to bring lawsuits to enforce state-law permit conditions that are beyond the scope of the CWA. In this citizen suit, an environmental group alleges that when rain falls on portions of a terminal in Tacoma, Washington, referred to as “the Wharf,” it runs into a body of water carrying with it metals and other materials. Even though federal regulations issued by the EPA do not regulate this stormwater discharge, the group maintains that the discharge is subject to regulation under permits issued under state law by Washington. The 9th Circuit agreed and, splitting from the 2nd Circuit, held that state permits are enforceable in a citizen suit even if they exceed the requirements of federal regulations.
We argue in our brief that the 9th Circuit falls on the wrong side of the split by permitting private plaintiffs to bring an action in federal court for alleged violations of state law. The 9th Circuit’s misreading of the citizen-suit provision exposes permit-holders, including governmental and non-governmental organizations, municipalities, and private companies, to costly citizen-suit litigation in federal court based on state regulatory regimes.