EPA and Army Corps propose narrower WOTUS definition

The U.S. Environmental Protection Agency (EPA) and the U.S. Army Corps of Engineers have issued a supplemental notice of proposed rulemaking to redefine ‘waters of the United States’ (WOTUS) under the Clean Water Act.

The proposal suggests a ‘perennial’ standard, which would limit federal jurisdiction over streams and wetlands to those containing water year-round. This approach offers two primary options: defining ‘relatively permanent’ waters as perennial, or requiring perennial surface water to establish a wetland’s continuous surface connection to a jurisdictional water. If adopted, this would represent the narrowest definition of WOTUS the agencies have enforced, potentially reducing federal oversight of many waterways, particularly in arid and semi-arid regions.

This supplemental notice seeks public feedback on whether the final rule should follow the initial November 2025 proposal or adopt these new perennial standards. A 30-day comment period is currently open and is scheduled to close on October 9, 2026.