The U.S. Army Corps of Engineers (USACE), in coordination with the EPA, regulate potential impacts to wetlands and other water of the United States (WOTUS) under the Clean Water Act (CWA § 404) and the Rivers and Harbors Act of 1899 (RHA § 10). A critical distinction exists between wetland classification (the ecological identification of a wetland based on physical, hydrological, and biological indicators) and a jurisdictional determination (a regulatory determination of whether that wetland is federally regulated under the WOTUS definition).

The proposed revisions re-define WOTUS and could directly impact landowners, developers, and stakeholders in terms of compliance and permitting obligations.

The agencies seek to provide a revised definition of WOTUS to increase clarity, consistency, and predictability for landowners and related entities. Additionally, changes in jurisdictional boundaries between federal and state/tribe entities are proposed for revisions.

The proposed revisions include redefining key terms, as follows:

• “Relatively permanent”: to refer to surface waters that have water year-round or continuously during certain seasons
• “Continuous surface connection”: a requirement for wetlands to be jurisdictional adjacent wetlands, only if they are indistinguishable from the water body
• Updating the following definitions to clarify federal jurisdictional boundaries: “tributary”, “ditch”, “prior converted cropland”, and “waste treatment system”

Revisions are also proposed to address the jurisdictional status of interstate water categories for lakes and ponds. Through this revision, only relatively permanent waterbodies with continuous surface connection to jurisdictional waters would qualify. Exclusion categories for waste treatment systems, converted croplands, ditches, and ground water are proposed for revisions.

For full details of the revisions and action items, see the proposal available online [Updated Definition of ‘‘Waters of the United States’’].

With these revisions in place, the number of wetlands subject to federal jurisdiction under the CWA will be significantly reduced. In particular, those wetlands previously considered “adjacent” may not longer be jurisdictional if a continuous surface connection cannot be demonstrated.

The proposal for revisions was published on November 20, 2025. A public comment period is open until January 5, 2026. The agencies will host two hybrid public meetings in addition to providing online resources. Please note, registration is required to speak at the public meetings. For more information on the public meetings and how to submit comments, see Section II Public Participation of the proposal.