On May 25, the U.S. Supreme Court issued a decision in the Sackett v. Environmental Protection Agency case, narrowing the scope of “waters of the United States” that may be regulated under the Clean Water Act.

The court’s decision rejected the “significant nexus” test and curtailed federal regulation to traditional navigable waters and other waters that are relatively permanent and connected to them. The ruling rejects the broad scope of WOTUS that the Environmental Protection Agency and U.S. Army Corps of Engineers have claimed jurisdiction over.

ABC applauded the ruling, stating in part:

“By rejecting the ‘significant nexus’ test, the Supreme Court took a critical step toward eliminating the costly regulatory uncertainty that has plagued construction projects around the country for decades without providing meaningful environmental protections for America’s waterways.”

The decision also challenges the Biden administration’s ABC-opposed 2023 WOTUS final rule, which relied heavily on the “significant nexus” test. Additional rulemaking or guidance documents will likely be necessary to bring the rule into compliance with the court’s decision.  

The agencies have yet to provide clarity on next steps, with the EPA issuing a statement in opposition to the ruling and stating on its website that “the agencies will interpret the phrase ‘waters of the United States’ consistent with the Supreme Court’s decision in Sackett.”