An October 9, 2015 ruling by the U.S. Court of Appeals for the Sixth Circuit bars U.S. EPA and the U.S. Army Corps of Engineers (USACE) from implementing their Clean Water Rule, which became effective August 28, 2015. Many argue the contentious rule’s definition of “waters of the United States” significantly expands both the number and types of waters subject to jurisdiction under the Clean Water Act. For this reason, numerous lawsuits challenging the Clean Water Rule were filed almost immediately following its publication in the Federal Register this past summer. Fourteen of the lawsuits were filed in assorted federal courts of appeal, all of which are now consolidated in the Sixth Circuit, and at one time no less than nine lawsuits were pending in seven different federal district courts. The Sixth Circuit’s decision to stay the Clean Water Rule was prompted by the threshold procedural issue of which of these courts has original jurisdiction to decide the substantive challenges to the rule. U.S. EPA contends that jurisdiction is proper in the court of appeals, whereas states and non-governmental parties involved in the lawsuits favor resolution in the district courts.

The stay is expected to remain in place until the Sixth Circuit resolves the question of original jurisdiction following additional briefing by the litigants. In the meantime, the Sixth Circuit has directed U.S. EPA and USACE to rely on the “significant nexus” test provided in Rapanos v. United States, a 2006 U.S. Supreme Court decision, in determining whether waters are subject to regulation under the Clean Water Act. In Rapanos, the Court held that certain types of waters, such as tributaries and wetlands, that have a significant nexus, but not merely a hydraulic connection, to traditional navigable waters are subject to jurisdiction under the Clean Water Act. The Rapanos significant nexus test is preferred by many parties because under this test U.S. EPA and USACE have greater discretion to utilize case-specific analysis of waters in making their jurisdictional determinations. The root of the controversy surrounding the Clean Water Rule stems from agencies’ attempt to more precisely define waters of the United States by broadly defining certain concepts and terms that lend themselves to case-specific analysis under the Rapanos significant nexus test. By more precisely defining waters of the United States, the agencies have arguably broadly expanded the universe of jurisdictional waters and reduced their ability to utilize the case-specific analysis of waters preferred by many parties.