On May 25, 2023, the United States Supreme Court ruled in Sackett v. Environmental Protection Agency, 143 S. Ct. 1322 (2023) to narrow the scope of the Clean Water Act’s (“CWA”) regulations governing wetlands. The Court held that for wetlands to be regulated under the CWA, the wetlands must be connected to traditional navigable waters and have a continuous surface connection with that water. Id. at 1344. The Court interpreted the CWA’s applicability of the term “waters of the United States” to include “only those relatively permanent, standing or continuously flowing bodies of waters.” Id. at 1336. To fall under federal regulation, wetlands must be “indistinguishable from waters of the United States.” Id. at 1341. This decision significantly reduces the power of the Environmental Protection Agency (“EPA”) to regulate the nation’s wetlands and waterways.

The Sackett case arises from an Idaho couple’s excavation of their property near a lake. Three days after the Sacketts started excavation, the EPA stopped work on the project because the couple failed to get a permit to disturb the wetlands on their property.

The case was unanimously decided in favor of the Sacketts, but the Court was divided on how far to go in limiting the EPA’s authority. The five-justice majority issued a ruling that reduces the number of wetlands governed under the CWA. The majority’s narrow interpretation of the CWA does not include wetlands, such as swamps, marshes, or seasonal streams, that are not connected at the surface to larger water systems. Further, construction of roads, levees, or other barriers could potentially remove an area from regulation under the CWA.

The Court’s decision will likely open new wetland areas to development, but, as Justice Kavanaugh states in his concurring opinion, may have significant repercussions for water quality and flood control. Id. at 1362. Further, despite not being directly connected to navigable waters, many of the wetlands no longer regulated by the CWA are nevertheless ecologically connected to larger water bodies.