The Clean Water Act protects a water body from pollution if it is classified as a “water of the United States” (WOTUS). The Act does not provide a definition for this term; this is left up to a rule that is to be made by federal agencies, in this case the EPA and the Department of the Army. In response to an executive order issued during the Trump administration, these agencies promulgated the Navigable Waters Protection Rule, which contained a definition of WOTUS that removed protection from about 51% of U.S. wetlands and 18% of U.S. streams. 

In an August 30 ruling on the case Pasqua Yaqui Tribe v. EPA, Judge Rosemary Márquez of the U.S. District Court for the District of Arizona remanded the Navigable Waters Protection Rule to the agencies, to be revised in a way that will protect many more streams and wetlands. Judge Márquez went on to vacate the existing rule, meaning that it cannot be applied in its present form, pending its revision or replacement. She ruled that the Navigable Waters Protection Rule violated the text and purpose of the Clean Water Act, and would cause irreparable harm to numerous streams.

This has left two challenges: adoption of a new definition of WOTUS that can be applied by regulatory agencies, and promulgation of an entirely new rule to replace the Navigable Waters Protection Rule that was struck down. On October 13, the EPA and Department of the Army submitted a revised definition of WOTUS to the Office of Management and Budget in response to the August 30 federal court ruling. Then, on November 18, the two agencies announced the signing of a proposed rule that will include the revised definition of WOTUS. The agencies propose to put back into place the pre-2015 definition of WOTUS, updated somewhat to comply with subsequent Supreme Court decisions. To address longer-term regulatory issues, the agencies have announced a plan to consult with states, tribes, local governments, and a broad array of stakeholders in a second round of rulemaking. The deadline for nominating participants in this regional roundtable process, which is planned to occur in early 2022, was extended to December 1, 2021.