EPA and Army Corps Propose New Definition for WOTUS

On November 17, 2025, the U.S. Environmental Protection Agency (EPA) and the U.S. Army Corps of Engineers (Corps) proposed a new rule to change the definition of “waters of the United States” (WOTUS).¹ Defining WOTUS may seem technical or insignificant, but it is central to understanding which bodies of water are subject to federal jurisdiction under the Clean Water Act (CWA). It affects day-to-day decisions such as how to comply with federal law, when permits are required, and which permits are needed. According to the EPA and the Corps, by providing a clear and durable definition, this proposal may help accelerate economic growth and opportunities.²

Background

In 1972, Congress passed the CWA, which, among many other things, made it unlawful to “discharge pollutants from a point source into navigable waters.”³ The CWA defines “navigable waters” as “the waters of the United States.”⁴ However, since the 1970s, the application and scope of WOTUS has proven difficult for both the executive and judicial branches to determine. Specifically, courts have struggled to determine whether Congress intended for this definition to include wetlands and bodies of water that aren’t continuously flowing throughout the year.

In May 2023, the Supreme Court in Sackett v. EPA (commonly called Sackett II) addressed whether the EPA’s definition of WOTUS exceeded its statutory authority.⁵ At the time, this definition included what is commonly referred to as the “significant nexus test,” which originated from Justice Kennedy’s concurrence in Rapanos v. United States.⁶ In Rapanos, Justice Kennedy stated that waters or wetlands possessing a significant nexus to navigable waters could be considered WOTUS.⁷

In Sackett II, the EPA included wetlands as part of WOTUS so long as they had a significant nexus to navigable waters.⁸ However, the court struck down the nexus test and noted that in order for wetlands or other bodies of water to be considered WOTUS they must be “indistinguishably part of a body of water that itself constitutes ‘waters’ under the CWA.”⁹ Ultimately, Sackett II restricted the scope of WOTUS and forced the agencies to modify its definition.

The EPA and Corps Move to Change the Definition of WOTUS

In short, the proposed new definition does three things: (1) it incorporates and defines many key terms used in Sackett II, such as “relatively permanent” and “continuous surface connection,” (2) it limits the federal jurisdiction over bodies of water in the U.S., and (3) it expands upon the list of exceptions to WOTUS by adding exclusions for groundwater, certain ditches, waste treatment systems, etc.¹⁰ The proposal itself will undergo a notice and comment period before the rule can be finalized, which often takes many months or longer before a rule is finally implemented.

Since the announcement of this proposal, there have been mixed opinions. Those in favor of the proposal argue it brings clarity to the permitting process. For example, the National Association of Home Builders suggests this change will help provide clarity to home builders by clarifying when wetlands are subject to federal jurisdiction.¹¹ Specifically, the proposal states that wetlands are subject to federal jurisdiction only when they have a continuous surface connection to a body of water subject to federal jurisdiction under the CWA, and it must do so for a certain duration annually.¹² Those opposing this proposal argue that by limiting the scope of protections offered to bodies of water, it puts at risk the “health of our rivers, lakes, and drinking water supplies.”¹³ On the other hand, others contend this gap in protections will likely be filled in by the states, with states like Washington already working on creating its own permitting program.¹⁴ However, it is not guaranteed that all states will fill this gap.

In the meantime, this proposal will go through a 45-day comment period through January 5, 2026, where the public may comment on their concerns and praises of this change.¹⁵ Any member of the public may submit a comment by visiting Regulations.gov, searching for and selecting the docket titled “Updated Definition of ‘Waters of the United States,’” and clicking “Comment,” then following the site’s instructions. It remains to be seen whether the proposal will be modified or if it will receive consequential pushback. Ultimately, if finalized, it will narrow federal jurisdiction while leaving room for states or Tribal programs to fill in the gaps. At the same time, the proposed rule provides clarity to farmers, ranchers, and developers, and may significantly impact the economy, critics warn it may leave waters less protected.

¹ EPA & Army Corps Unveil Clear, Durable WOTUS Proposal, Env't Prot. Agency (Nov. 17, 2025).
² Id.
³ Federal Water Pollution Control Act (Clean Water Act), 33 U.S.C. §§ 1251–1387.
⁴ 33 U.S.C. § 1362.
⁵ Sackett v. Env’t. Prot. Agency, 598 U.S. 651 (2023).
⁶ Rapanos v. United States, 547 U.S. 715, 717 (2006).
⁷ Id.
⁸ Sackett II, 598 U.S. at 1324.
⁹ Id. at 1339.
¹⁰ EPA & Army Corps Unveil Clear, Durable WOTUS Proposal, Env't Prot. Agency (Nov. 17, 2025).
¹¹ Evan Branosky, New WOTUS Rule Brings Clarity to Permitting Process, Nat'l Assoc. Home Builders (Nov. 20, 2025).
¹² EPA & Army Corps Unveil Clear, Durable WOTUS Proposal, Env't Prot. Agency (Nov. 17, 2025).
¹³ Charlotte Slovin, EPA Proposes Limits to Clean Water Act: What the Changes Mean, ABC News (Nov. 18, 2025).
¹⁴ Schwabe, Williamson & Wyatt PC, Navigating New Waters: Analysis of the Proposed WOTUS Rule, JDSUPRA (Nov. 21, 2025).
¹⁵ Id.