On December 30, 2022, the U.S. Environmental Protection Agency (EPA), and U.S. Army Corps of Engineers (Corps) announced a joint final rule for the revised definition of the “waters of the United States” (WOTUS). The new rule is consistent with the pre-2015 definition and is only the latest attempt in an approximately 20-year process to settle the scope of federal authority over wetlands under the Clean Water Act (CWA).

Pursuant to the final rule (and in addition to traditional navigable waters and wetlands), tributaries, adjacent wetlands, and ephemeral streams and features are jurisdictional if they meet either the relatively permanent standard or the significant nexus standard. The final rule also contains explicit exclusions from the definition of WOTUS, including prior converted cropland, ditches, water-filled depressions, and swales and erosional features.

The CWA prohibits the discharge of pollutants from a point source into “navigable waters” unless authorized under the CWA. The CWA defines “navigable waters” as “the waters of the United States, including the territorial seas.” The CWA does not define the term WOTUS, but EPA and the Corps have defined it by regulation for decades.

Largely in response to controversial decisions from the U.S. Supreme Court, over the past three presidential administrations EPA and the Corps have issued multiple rules and guidance documents that revise the definition of WOTUS, alternatively expanding or contracting federal jurisdiction. The new final rule will revise again those regulations governing EPA (at 40 CFR Part 120) and the Corps (at 33 CFR Part 328) by reversing changes made during the Trump administration.

Notably, however, the final rule comes ahead of a Supreme Court ruling in Sackett v. Environmental Protection Agency, likely to be decided in the coming months, which could upend the final rule. The ruling in Sackett will determine “the proper test for determining whether wetlands are ‘waters of the United States’ under the Clean Water Act,” establishing the relatively permanent standard, significant nexus standard, or some other standard to be applied in determining federal jurisdiction.

The outcome of this case will not only inform applicability of the final rule, but also whether the Biden administration will pursue the additional rulemaking (to be completed in 2024) it announced last fall to further revise and refine the WOTUS definition. While EPA’s news release announcing the final rule states that this rule “establishes a durable definition” of WOTUS, suggesting that the agencies may drop the 2024 rulemaking, how the agencies proceed – and what exactly qualifies as a WOTUS – will no doubt be influenced by the Court’s decision in Sackett.

The practical impact of the final rule, once published in the Federal Register, is that the Corps will continue to utilize the pre-2015 regulatory regime in making approved jurisdictional determinations (AJDs), which determine the presence (or absence) of WOTUS on a parcel and therefore the scope of federal permitting jurisdiction. The definition of WOTUS that is in effect at the time the Corps completes an AJD – not at the time of the request for an AJD – governs the Corps’ AJD determination.

Accordingly, pending AJD requests, or new AJD requests, will be completed consistent with the pre-2015 regulatory regime, a regime the agencies have been utilizing since a 2021 district court decision that vacated the Trump administration’s Navigable Waters Protection Rule (NWPR) defining WOTUS. For any currently pending permit action that relies on an NWPR AJD, or for any future permit application that intends to rely on an NWPR AJD, the Corps will discuss with the applicant whether they would like to receive a new AJD under the pre-2015 regulatory regime or whether the applicant would like to proceed in reliance on a preliminary JD or no JD whatsoever.

The rule is set to become effective 60 days after publication in the Federal Register. A pre-publication version of the rule is available here.