On September 8, 2023, the Environmental Protection Agency (EPA) and the U.S. Army Corps of Engineers (COE) published their Amendments to the “Revised Definition of ‘Waters of the United States’”. The revisions are an attempt to conform the agencies’ January 18, 2023, "Waters of the United States" rule to the U.S. Supreme Court’s decision in Sackett v. EPA, No. 21-454 on May 25, 2023. It is a direct final rule and thus effective immediately on publication in the Federal Register.
The revisions to the rule are straightforward; the definition of waters of the United States (WOTUS)—those waters and wetlands that are subject to regulation under the Clean Water Act (CWA)—has been revised to eliminate jurisdiction based on the test commonly referred to as the “significant nexus” test, that is, whether or not waters or wetlands “either alone or in combination with similarly situated waters in the region, significantly affect the chemical, physical, or biological integrity of” waters that are: 1. currently used, or were used in the past, or may be susceptible to use in interstate or foreign commerce, including all waters which are subject to the ebb and flow of the tide; 2. the territorial seas; or 3.interstate waters. The Sackett decision expressly rejected the significant nexus test. For a good analysis of the Sackett opinion, see Robin Kundis Craig, Does Sackett bring clarity to “waters of the United States”, Trends (July/Aug. 2023).
Wholly consistent with Sackett, interstate wetlands are no longer a jurisdictional category, and wetlands “adjacent” to a jurisdictional water are jurisdictional only if they have a “continuous surface connection” to it. The revised rule has now replaced the prior definition of “adjacent,” which previously included “neighboring” wetlands, with this decidedly narrower definition.
The rule will likely be challenged by regulated interests on three key points: 1. the decision to make the rule amendment immediately effective as a direct final rule precludes public comment on the revisions; 2. the failure to exclude ditches as jurisdictional based on language in the Sackett decision suggesting that only natural waterbodies can be WOTUS; and 3. the failure to define “adjacent” to add “and indistinguishable from,” which was a key point in the Sackett opinion. Regarding wetlands, the Sackett Court expressly held that CWA jurisdiction “extends to only those ‘wetlands with a continuous surface connection to bodies that are [WOTUS] in their own right,’ so that they are ‘indistinguishable’ from those waters.” Sackett, No. 21-454, slip op. at 27. The omission of the phrase “so that they are indistinguishable from those waters” will almost certainly be challenged, particularly since the preamble does not elaborate on the new definition of “adjacent” in any way.
The following chart was taken from the Final Rule’s Fact Sheet and was released by EPA. It presents a summary of the various changes in the revised Final Rule:
| Jurisdictional Category | Key Changes to the January 2023 Rule Regulation Text | Regulatory Text Paragraph |
| Traditional Navigable Waters | No changes | (a)(1) |
| Territorial Seas | No changes | (a)(1) |
| Interstate Waters | Removing interstate wetlands from the text of the interstate waters provision | (a)(1) |
| Impoundments | No changes | (a)(2) |
| Tributaries | Removing the significant nexus standard | (a)(3) |
| Adjacent Wetlands | Removing the significant nexus standard | (a)(4) |
| Additional Waters | Removing the significant nexus standard; removing wetlands and streams from the text of the provision | (a)(5) |
| Definition | Key Changes to the January 2023 Rule Regulation Text | Regulatory Text Paragraph |
| Wetlands | No changes | (c)(1) |
| Adjacent | Revised definition to mean "having a continuous surface connection" | (c)(2) |
| High tide line | No changes | (c)(3) |
| Ordinary high water mark | No changes | (c)(4) |
| Tidal waters | No changes | (c)(5) |
| Significantly affect | Deleted definition | (c)(6) |
