LEGAL UPDATE: New Proposed Environmental Rule Summary


On November 18, 2021, the Biden Administration took the first step toward redefining Waters of the United States (“WOTUS”) under the Clean Water Act by submitting a proposed rule for publication to the Federal Register. WOTUS is a term used in the Clean Water Act that outlines which waters are subject to federal oversight. In June, EPA and the Army Corps of Engineers (collectively referred to as the “agencies”) announced their intent to revise the definition of WOTUS through a two-step rulemaking process.

The Trump Administration most recently revised the definition of WOTUS in 2020 pursuant to its Navigable Waters Protection Rule (“NWPR”). The NWPR was recently vacated by the Arizona District Court. In response to that decision, the agencies halted implementation of the NWPR nationwide, even though they had not yet set forth a definition of WOTUS to use in place of the Trump Administration’s definition.

With this proposed rulemaking, the Biden Administration seeks to officially replace the NWPR while the agencies continue to develop a new definition of WOTUS that they will propose at some point in the future.  The current proposed rule would implement the pre-2015 regulations regarding WOTUS with some modifications to reflect post-2015 Supreme Court decisions. Under the proposed rule, the agencies interpret WOTUS to include:

  • traditional navigable waters, interstate waters, and the territorial seas, and their adjacent wetlands;
  • most impoundments of “waters of the United States”;
  • tributaries to traditional navigable waters, interstate waters, the territorial seas, and impoundments that meet either the relatively permanent standard or the significant nexus standard;
  • wetlands adjacent to impoundments and tributaries, that meet either the relatively permanent standard or the significant nexus standard; and
  • “other waters” that meet either the relatively permanent standard or the significant nexus standard.

The proposed rule also updates the “relatively permanent standard” to mean waters that are "relatively permanent, standing or continuously flowing and waters with a continuous surface connection to such waters." It also codifies Justice Kennedy’s significant nexus standard from the 2006 Rapanos v. United States opinion to mean "waters that either alone or in combination with similarly situated waters in the region, significantly affect the chemical, physical or biological integrity of traditional navigable waters, interstate waters or the territorial seas."  The pre-publication version of the proposed rule can be found here

The agencies are expected to eventually put forth a second rulemaking that will set forth a new definition of WOTUS. The agencies have stated that they are committed to crafting a durable definition of WOTUS that is “informed by diverse perspectives and based on an inclusive foundation.” 

ELPO Law Environmental Team: Attorneys LaJuana Wilcher (; Read bio), Sarah Jarboe (; Read bio), and Joye Beth Spinks (; Read bio) 270-781-6500