The EPA today announced that the Waters of the United States (WOTUS) rule, jointly proposed by EPA and the Army Corps of Engineers in June 2019, is now final. The new rule replaces the 2015 Obama Administration’s rule, which EPA and the Corps rescinded last October.

The Clean Water Act confers federal jurisdiction over “navigable” waters, defined in the Act as “waters of the United States, including the territorial seas.” Congress left it to the agencies and courts to add meat to this skeletal definition. As it turns out, that has been no easy task.

The agencies have tried multiple times to bring clarity to the scope of CWA jurisdiction, resulting in an enormous body of litigation and a few Supreme Court cases. These cases culminated in the 2006 ruling in Rapanos v. U.S., in which a divided Supreme Court agreed that the government had overreached but could not agree as to how. Justice Scalia, writing for the plurality, would have limited jurisdiction to running waters and adjacent wetlands. In a concurring opinion, Justice Kennedy instead would have conferred jurisdiction where there is a “significant nexus” to a navigable water.

The subsequent 2015 rule adopted the Kennedy approach, whereas the new 2020 rule follows Scalia. As reported here, the new rules are not likely to implement the lofty goals of the CWA, viz., to “restore and maintain the chemical, physical, and biological integrity of the Nation’s waters.” That is the conclusion of EPA’s own Science Advisory Board:

At the EPA Science Advisory Board (SAB) meeting on June 5-6, 2019, the SAB discussed the scientific and technical underpinnings of the proposed WOTUS rule and concluded that aspects of the proposed rule are in conflict with established science, the existing WOTUS rule developed based on the established science, and the objectives of the Clean Water Act.

Several states and environmental organizations have announced their intent to challenge the rule’s disregard for what is known about the interconnectedness of wetlands and running waters. As quoted in the New York Times coverage of the new rule, Vermont Law School environmental law professor Patrick Parenteau concisely summarized the case: “The legal standing all has to do with whether you have a rational basis for what you’re doing. And when you have experts saying you’re not adhering to the science, that’s not rational, it’s arbitrary.”

Lawyers advising clients as to the reach of CWA jurisdiction can only recommend caution. We will not have clarity on the scope of WOTUS any time soon.