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U.S. Supreme Court Issues Ruling in Clean Water Act Case

June 5, 2023

On May 23, the U.S. Supreme Court issued its ruling in Sackett v. Environmental Protection Agency (Sackett II). The decision caps the long-running saga about how to define “Waters of the United States” (WOTUS) under the Clean Water Act (CWA)—a threshold, jurisdictional element for any claim under the CWA. While providing greater clarity, some questions still remain after Sackett II that will likely be addressed through regulatory action or further court decisions.

Background on the Clean Water Act and the WOTUS Controversy

The CWA generally prohibits the discharge of a pollutant into navigable waters, defining “navigable waters” as “the waters of the United States, including the territorial seas,” which included at least some “wetlands.” Going back to 1985 in United States v. Riverside Bayview Homes, Inc., the Supreme Court has grappled with defining which wetlands the CWA reaches. Since the U.S. Supreme Court’s split decision in Rapanos v. United States Army Corp of Engineers, every successive presidential administration has attempted to administratively define “waters of the United States.” Yet those definitions have proved to be fraught with politics and judicial action leaving this important jurisdictional issue unsettled for years.

In Sackett II, the question before the Court was how far WOTUS actually extends and—more specifically—whether the U.S. Court of Appeals for the Ninth Circuit, which heard the Sackett’s appeal from the findings of the U.S. District Court, set forth the proper test for deciding when wetlands are “waters of the United States” under the CWA. The Ninth Circuit adopted the approach employed by Justice Kennedy’s plurality opinion in Rapanos, relying on whether the water body has a “significant nexus” to a Water of the United States. The Sacketts challenged that approach and its application to their wetland.

The Sackett II Decision and Its Impact

Somewhat surprisingly, the Sackett II court unanimously determined that the Sackett’s wetland was not a jurisdictional water and unanimously rejected the significant nexus definition as too vague. The significant nexus test required a “significant nexus” between the wetland and its adjacent navigable waters. The test suggested that this existed when “the wetlands, either alone or in combination with similarly situated lands in the region, significantly affect the chemical, physical, and biological integrity” of those waters.

Rejecting that test, the Court’s 5-4 split between Justice Alito’s majority and Justice Kavanaugh’s concurrence clearly established that the significant nexus test no longer applies. The majority emphasized that the CWA’s inclusion of “wetlands adjacent” to other waters clearly includes at least some wetlands as “waters of the United States.” But the Court also emphasized that wetlands can only be considered a WOTUS under the CWA if the wetland is a part of the otherwise covered “water.” Per the majority, that occurs when: (1) the water adjacent to a wetland is “a relatively permanent body of water connected to traditional interstate navigable waters” and (2) the wetland has a “continuous surface connection with that water, making it difficult to determine where the ‘water’ ends and the ‘wetland’ begins.”

In response, Justice Kavanaugh’s lead concurrence claimed that the majority’s new test narrows the CWA’s coverage of “adjacent” wetlands by limiting the Act to merely “adjoining” wetlands. The concurrence reasoned that, while “adjoining” means only contiguous, “adjacent” includes not only contiguous wetlands but also neighboring wetlands that may be separated by features such as a dike, barrier, berm, or dune. The concurrence further cautioned that such narrow CWA coverage could cause “significant repercussions for water quality and flood control throughout the United States.”

Some Key Takeaways

Sackett II significantly limits the jurisdictional reach of the CWA over wetlands and provides greater clarity in determining when a particular wetland is a “WOTUS.” But some gray areas and regulatory uncertainty remain under the new Sackett II test. Those include defining exactly how “continuous” a surface connection must be to qualify, what are acceptable “temporary interruptions” in surface connection, and related concerns. Because both EPA’s current and its proposed WOTUS rule incorporate the “significant nexus” test, the Biden Administration is likely to undertake a new rulemaking. Additionally, some states will need to evaluate their own wetland rules in light of this opinion, which may incorporate an obsolete jurisdictional framework from the CWA.

Clark Hill will continue to monitor and update as state and federal agencies evaluate the impact of Sackett II.

The views and opinions expressed in the article represent the view of the authors and not necessarily the official view of Clark Hill PLC. Nothing in this article constitutes professional legal advice nor is it intended to be a substitute for professional legal advice. 

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