The Nickel Report

The definition of “waters of the United States” (WOTUS) establishes the geographic reach of the Clean Water Act (CWA), including the Section 404 permitting program. The Supreme Court set the parameters within which the agencies may treat aquatic features as WOTUS when it decided Sackett v. EPA. In November 2025, the US Environmental Protection Agency and US Army Corps of Engineers issued a WOTUS proposed rule to implement Sackett. Last month, the agencies issued a supplemental proposed rule “to supplement and seek additional comment on certain aspects” of the 2025 proposal. In this post, we examine how the 2025 Proposed Rule and 2026 Supplemental Proposed Rule line up with the findings of Sackett.

The U.S. Environmental Protection Agency (EPA) and U.S. Army Corps of Engineers (Corps) (jointly, “the Agencies”) recently issued guidance addressing implementation of the definition of “waters of the U.S.” (WOTUS). The guidance specifically provides direction on the proper implementation of “continuous surface connection” as it relates to adjacent wetlands.