The U.S. Environmental Protection Agency (EPA) has taken another step in its ongoing effort to revise the definition of “Waters of the United States” (WOTUS) under the Clean Water Act.
On June 30, the EPA transmitted a supplemental proposed rule to the White House Office of Management and Budget (OMB) for interagency review. According to the EPA, the supplemental proposal is intended to gather additional public input on specific aspects of the November 2025 proposed WOTUS rule before the agencies move toward a final regulation.
What We Know
At this point, we do not yet know what changes are included in the supplemental proposal.
The document has not been published in the Federal Register, and the EPA has not released the regulatory text for public review. As a result, much of the discussion circulating about potential revisions remains speculative.
What to Expect Next
Once the supplemental proposal is published, stakeholders should expect:
• Release of the proposed regulatory language;
• An additional public comment period;
• EPA and the U.S. Army Corps of Engineers’ review of comments before issuing a final rule.
The timing and duration of the comment period will become clear once the proposal is officially published.
Why It Matters
The WOTUS definition continues to be one of the most consequential regulatory issues affecting infrastructure, energy, transportation, mining, development, and natural resource projects nationwide. Changes to the rule may directly affect:
• Clean Water Act Section 404 permitting requirements;
• Jurisdictional wetland determinations;
• Project planning and design;
• Environmental compliance schedules; and
• Overall permitting risk and timelines.
Until the supplemental proposal is released, the current regulatory framework remains in effect.
At Headway Environmental, we are closely monitoring this rulemaking and will provide additional analysis once the actual regulatory language becomes available. We expect the supplemental proposal to generate significant interest across the environmental consulting, regulatory agencies, and regulated communities, and we will share practical insights on what the changes may mean for our clients.