EPA Publishes “Final” Definition of “Waters of the United States”

Effective September 8, 2023, the new definition limits federal jurisdiction over water quality by removing the “significant nexus standard” and redefining what wetlands are “adjacent.”

The U.S. Environmental Protection Agency (“EPA”) and U.S. Army Corps of Engineers (“Corps”) recently amended what constitutes “waters of the United States” (“WOTUS”). The Clean Water Act, 33 U.S.C. § 1251 et seq. (“CWA”), is the primary federal statute regulating water quality in the United States. It uses WOTUS as a limit on federal jurisdiction. Only when pollutants or dredge material go into WOTUS may the EPA or Corps require a permit. §§ 1342 & 1344.

In Sackett v. Environmental Protection Agency, 598 U.S. 651 (2023), the U.S. Supreme Court rejected much of the then-existing WOTUS definition. We analyzed the Sackett decision here.

The EPA and Corps, in a final rule, have now redefined WOTUS to conform to the Sackett court’s holding. A copy of the final rule is here. In particular, the new definition implements two significant changes:

1. Repeal of “Significant Nexus Standard.” While WOTUS previously included any wetlands with a “significant nexus” to WOTUS, the court in Sackett rejected that broad approach. 598 U.S. at 681. This amendment likewise eliminates that standard.
2. Narrowing of The Definition of “Adjacent Wetlands.” Adjacent wetlands could previously qualify as WOTUS if they were “bordering, contiguous, or neighboring” to other WOTUS. But to constitute WOTUS, “adjacent wetlands” must now “hav[e] a continuous surface connection” to WOTUS. 40 C.F.R. §  120.2(c)(2).

This new WOTUS definition implements the Supreme Court’s direction that adjacent wetlands must be “indistinguishable” from other WOTUS to themselves constitute WOTUS. Sackett, 590 U.S. 678. More simply, to assert jurisdiction, the federal regulator must (1) identify a relatively permanent body of water that connects to traditional interstate navigable waters and (2) show that the wetland at issue has a continuous surface connection with that water, such that it is difficult to determine where the water ends and the wetland begins. Id. at 679. This amendment should simplify jurisdictional determinations and lessen the CWA’s reach.

The final rule took effect September 8, 2023. The agencies have not indicated whether they intend to reconsider projects adjudicated under prior WOTUS definitions. Despite the final rule, the agencies will likely address nuances of its application via agency guidance and practice.

Attorneys at Baird Holm LLP have significant experience in water law and environmental compliance. They regularly assist clients in negotiating with federal agencies regarding WOTUS permits and jurisdictional determinations. Please do not hesitate to contact us if you have questions about WOTUS, the Clean Water Act, or any related matter.