The Clean Water Rule, as it is known, represents a regulatory change to the definition of "waters of the United States" as that term is used in the federal Clean Water Act ("CWA"). In changing the definition of this term, the Clean Water Rule redefined the limits of federal wetlands permitting jurisdiction on private property pursuant to the CWA Section 404 wetlands permitting program administered by the U.S. Army Corps of Engineers. The Clean Water Rule is the result of a multi-year effort by the U.S. Environmental Protection Agency ("EPA") and the Corps, and is the federal government's response to several U.S. Supreme Court decisions that called into question the Corps' expansive view of its Section 404 permitting jurisdiction.

Once promulgated in 2015, the Clean Water Rule was immediately challenged by a host of states as well as private parties in a number of federal courts, alleging, among other things, that the scope of the Clean Water Rule exceeded the authority of the CWA. Finding that the petitioners had a high likelihood of success, the U.S. Court of Appeals for the Sixth Circuit stayed the Clean Water Rule nationwide pending further action of the court. Among those states challenging the Clean Water Rule was Oklahoma, whose Attorney General, Scott Pruitt, is President Trump's nominee for EPA Administrator. Given the Sixth Circuit's suspension of the Clean Water Rule, and the nomination of Mr. Pruitt for the top job at EPA, it seems unlikely that the Clean Water Rule will survive in its current form. Moreover, on January 13, the U.S. Supreme Court agreed to hear argument on the issue of whether jurisdiction over challenges to the Clean Water Rule should sit with federal appellate or district courts. The Court's grant of review on this jurisdictional issue may allow the Trump Administration and Congress to focus on eliminating or replacing the rule while the contentious legal challenges await the Supreme Court's jurisdictional decision.