On August 29, 2023, the EPA and the U.S. Army Corps of Engineers (Corps) announced a final rule amending the 2023 definition of “waters of the United States (WOTUS)” to conform with the recent U.S. Supreme Court (SCOTUS) decision in Sackett v. EPA.

Having a clear and defensible definition of WOTUS is critical for Clean Water Act (CWA) regulations and enforcement.

The Sackett decision stated, “Wetlands that are separate from traditional navigable waters cannot be considered part of those waters, even if they are located nearby.”

The ruling means the EPA can only regulate federal streams, rivers, oceans, and lakes and wetlands with a “continuous surface connection to those bodies.”

“We have worked with EPA to expeditiously develop a rule to incorporate changes required as a result of [SCOTUS’s] decision in Sackett,” said Michael L. Connor, assistant secretary of the Army for Civil Works, in an EPA news release. “With this final rule, the Corps can resume issuing approved jurisdictional determinations that were paused [due to] the Sackett decision. Moving forward, the Corps will continue to protect and restore the nation’s waters in support of jobs and healthy communities.”

While the EPA and Corps’s 2023 rule defining WOTUS wasn’t directly before the Supreme Court, the Sackett decision made clear that certain aspects of the 2023 rule are invalid. The current amendments issued were limited to changing only the aspects of the 2023 rule that became invalid after the Sackett decision was finalized.

The revised final rule removes the significant nexus test from consideration when identifying tributaries and other waters as federally protected. It also revises the adjacency test when identifying federally jurisdictional wetlands, clarifies that interstate wetlands don’t fall within the interstate waters category, and clarifies the types of features that can be considered under the “additional waters” category.

“The Supreme Court’s Decision in Sackett v. EPA, issued on May 25, 2023, created uncertainty for [CWA] implementation,” adds the Agency news release. “The agencies are issuing this amendment to the 2023 rule expeditiously—three months after the Supreme Court decision—to provide clarity and a path forward consistent with the ruling. With this action, the [Corps] will resume issuing all jurisdictional determinations. Because the sole purpose of this rule is to amend specific provisions of the 2023 Rule that are invalid under Sackett, the rule will take effect immediately.”

With the revised WOTUS definition, many regulatory decisions will now move to state and tribal authority, where they will be determined by state and tribal definitions that determine the waters under their authority.

“The January 2023 Rule also provided a number of exclusions. EPA states that none of those exclusions were amended,” Mitchell, Williams, Selig, Gates & Woodyard PLLC says in a JD Supra article. 

“Note that many delegated states (including Arkansas) have their own statutes to authorize their environmental regulatory activities,” Mitchell Williams continues. “Further, many of these states have key jurisdictional definitions that may in fact be broader than the corresponding federal terms.”

For more information on the amended rule, see the agencies’ Fact Sheet.