New New WOTUS: I’ll see your Rapanos and Raise You Some “Additional” Waters

On December 30, 2022, the U.S. Environmental Protection Agency and the U.S. Department of the Army (the Agencies) announced the final “Revised Definition of 'Waters of the United States’” rule which will be effective 60 days after it is published in the Federal Register (see here).

The rule is highly consistent with the proposed rule the Agencies published in December 2021 (see here).

Both the proposed and final rules primarily reinstate the pre-2015 regulatory regime as explained in the Agencies’ guidance issued after the Supreme Court decision Rapanos v. United States, 547 U.S. 715 (2006), but then add one more category of covered water (see here).

The rule regulates seven broad categories:

  1. “Traditional” navigable waters, including those “susceptible to use” in interstate commerce
  2. Territorial seas
  3. All interstate waters of any size
  4. Impoundments of otherwise WOTUS
  5. Tributaries of the above waters that:
    • “are relatively permanent, standing or continuously flowing bodies of water” (the Justice Scalia test in Rapanos); OR
    • have a significant nexus with a (1), (2), or (3) water (the Agencies’ interpretation of Justice Kennedy’s test in Rapanos)
  6. Wetlands that:
    • are adjacent to a (1), (2), or (3) water; OR
    • are adjacent to “relatively permanent, standing or continuously flowing” impoundments or tributaries AND either:
      • have a continuous surface connection to those waters (derivation of Scalia test); OR
      • have a significant nexus with a (1), (2), or (3) water (derivation of Kennedy test)
  7. “Additional” or “other” waters that either:
    • “are relatively permanent, standing or continuously flowing bodies of water with a continuous surface connection to” a (1), (2), (3), or (5) water (derivation of Scalia test); OR
    • have a significant nexus with a (1), (2), or (3) water (derivation of Kennedy test)

The main difference between the new rule and the pre-2015 regime is the return of the “additional” or “other” water category that was invalidated in the Supreme Court decision SWANCC v. USACE, 531 U.S. 159 (2001). The Agencies have attempted to salvage its legality by framing it according to the continuous surface connection / significant nexus tests of the Rapanos majority and plurality justices rather than its prior commerce clause-based definition.

The viability of that approach – which permeates the entire new WOTUS rule – is currently before the Supreme Court in Sackett v. EPA, No. 21-454. See Argument Transcript at The Agencies gave short shrift to that case in the Preamble to the final rule, explaining Sackett “is not a direct challenge to any of the rules defining ‘waters of the United States,’ but instead presents the question … in the context of a challenge to an EPA administrative compliance.” However, given the discomfort some justices and scholars – including Justice Kennedy himself – have expressed with the “significant nexus” standard, Sackett has the potential to be a sea change with significant consequences for the viability of the new WOTUS rule. How that unfolds will be a topic to watch in 2023.