Revised Definition of WOTUS Proposed

Updated 11/20/2025

A proposed rule to revise the definition of the “waters of the United States” (WOTUS) was published in the Federal Register today, November 20, 2025. The proposed rule from US EPA and the Department of the Army implements the Supreme Court’s decision in Sackett v. EPA and considers feedback from a wide range of sources.

See the new definition of “waters of the United States” from the proposed rule:

Under the agencies’ proposed rule, the term “waters of the United States” would include (1) traditional navigable waters and the territorial seas; (2) most impoundments of “waters of the United States;” (3) relatively permanent tributaries of traditional navigable waters, the territorial seas, and impoundments; (4) wetlands adjacent (i.e., having a continuous surface connection) to traditional navigable waters, impoundments, and tributaries; and (5) lakes and ponds that are relatively permanent and have a continuous surface connection to a traditional navigable water, the territorial seas, or a tributary. The agencies are also proposing to amend the exclusions for waste treatment systems, prior converted cropland, and certain ditches, and to add an exclusion for groundwater. Finally, the agencies are proposing to add definitions for “continuous surface connection,” “ditch,” “prior converted cropland,” “relatively permanent,” “tributary,” and “waste treatment system.”
Federal Register 52498, Updated Definition of the “Waters of the United States”

US EPA will accept comments on the proposed rule until January 5, 2026.

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Updated 03/25/2025 

EPA officially announced plans to revise the definition of Waters of the United States (WOTUS) in the Federal Register on March 24. In light of the Supreme Court's decision in Sackett v. EPA, EPA is also seeking input from the regulated community about the meaning and scope of key regulatory terms such as relatively permanent waters, continuous surface connection, and jurisdictional ditches.

Stakeholders and the public are invited to submit comments in writing or participate in upcoming WOTUS listening sessions to be hosted by EPA in April-May 2025. 

Read more: "WOTUS Notice: The Final Response to SCOTUS"

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2025 WOTUS Guidance From EPA, Army Engineers

US EPA has announced plans to revise, again, its definition of Waters of the United States (WOTUS) under the Clean Water Act. The regulatory definition of WOTUS determines, in part, which bodies of water—e.g., streams, rivers, lakes, wetlands, etc.—are protected by Federal law/regulations. 

The Agency, with the US Army Corps of Engineers, also provided new guidance on how the Clean Water Act will be enforced under this administration. Changes to the Waters of the US definition affect industry compliance with Federal water protection programs including: 

• Oil Discharge Notifications (40 CFR 110);
• Spill Prevention, Control, and Countermeasure Plans (40 CFR 112);
• NPDES Permitting and Stormwater Discharge Permits (40 CFR 122);
• The “per-industry standards” (40 CFR 405-471); and
• Dredge and Fill Permitting (33 CFR 323).

Why Change the WOTUS Definition Under the CWA?

In the Clean Water Act, Congress authorizes US EPA to regulate all “navigable waters.” How regulators interpret the term “navigable waters” has been the central issue of legal challenges for decades, including in two landmark Supreme Court cases—Rapanos v. United States (2006) and Sackett v. EPA (2012). The resolution of both cases led EPA to revise the definition of WOTUS.

One specific, long-running challenge for EPA has been to provide definitive, clear direction about the status of wetlands that are somehow “connected to” protected waters. 

Read more: Impact of Sackett v. EPA on CWA Compliance 

March 2025 WOTUS Guidance from EPA

EPA and the Army Corps of Engineers issued new joint guidance on WOTUS for the regulated community on March 12, 2025. It seems likely that any future rule to revise the Clean Water Act regulations will reflect the policy stated in this latest memo. 

EPA is interpreting WOTUS to include: 

“only those adjacent wetlands that have a continuous surface connection because they directly abut [a jurisdictional water] (e.g. they are not separated by uplands, a berm dike, or similar feature).” 

Wetlands that are “far removed from and not directly abutting covered waters” do not meet the legal standard to be a WOTUS, per the March 12 guidance. 

The memorandum also says: 

“The Sackett Court recognized that there may be some instances where that line drawing problem is difficult, such as during periods of drought or low tide or in those instances where there may be temporary interruptions in surface connection. The agencies will work to resolve these scenarios on a case-by-case basis and provide further clarity when appropriate…” 

Read the joint guidance from EPA and the Army Corps of Engineers:
“Continuous Surface Connection Under the Definition of WOTUS Under the CWA” 

Public Input on Future WOTUS Rule

EPA is also announcing public listening sessions and an open public comment docket to encourage input on post-Sackett WOTUS implementation from industry stakeholders, environmental and conservation groups, and the public. Listening sessions and the deadline for public comments will be announced in the Federal Register under the title "WOTUS Notice: The Final Response to SCOTUS." 

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