The U.S. Army Corps of Engineers and the Environmental Protection Agency published a rule postponing the effective date of the Clean Water Rule for two years, until February 6, 2020.

The Clean Water Rule defined the extent of jurisdiction under the Clean Water Act. It was supposed to have become effective on August 28, 2015, but was immediately challenged in multiple lawsuits and was eventually stayed nationwide by the Sixth Circuit. Disputes on the merits were put on hold while the courts decided whether the cases should proceed in the district courts or in the appellate courts.

The U.S. Supreme Court resolved that question in January, unanimously concluding that challenges belong in district courts. The resumption of litigation in district courts created the possibility that the Clean Water Rule would be stayed in some states but effective in others. The final rule postponing the effective date means that the pre-Clean Water Rule regulations will apply uniformly throughout the country.

The deferral is the latest action by the two agencies on the disputed rule. Following an executive order issued on February 28, 2017, the agencies announced a two-step process that would first rescind the Clean Water Rule and then develop a new rule defining “waters of the U.S.” — the term used to describe federal jurisdiction over aquatic areas — in accordance with the Scalia opinion in the Rapanos case. In June of 2017, the agencies took the first step and proposed rescinding the Clean Water Rule. This rulemaking is ongoing, and the timing of the second step has yet to be announced.