Updated May 25, 2023 - Politics & Policy

Supreme Court limits EPA's regulatory control over certain wetlands

The Supreme Court building in Washington, D.C., in May 2022. Photo: Celal Gunes/Anadolu Agency via Getty Images

The Supreme Court limited the Environmental Protection Agency's (EPA) ability to oversee certain bodies of water on Thursday, determining that the agency cannot regulate wetlands isolated from larger bodies of water.

Why it matters: It's the court's second major decision in recent years that dents the EPA's ability to control pollution after it imposed major constraints on the agency's authority to limit carbon emissions from power plants under the Clean Air Act last year.

  • The Supreme Court's ruling overturns a decision from the U.S. Court of Appeals' 9th Circuit, which sided with the EPA in 2021.

Details: The case settled by the court centered on an Idaho couple, Michael and Chantell Sackett, who sought to build a home on property that the EPA considered a protected wetland under the Clean Water Act.

  • The act allows the agency and the U.S. Army Corps of Engineers to regulate discharges of pollutants into "waters of the United States." The act doesn't define "waters of the United States," rather, it gives the EPA and the Army the authority to define the term through regulations.
  • The question before the court was to determine what wetlands should be considered U.S. waters under the Clean Water Act.

What they're saying: Justice Samuel Alito wrote in the opinion that the Clean Water Act only extends to wetlands "with a continuous surface connection" to larger regulated bodies of water.

  • The decision throws out a test created in a previous case by former Justice Anthony Kennedy, who said wetlands that have a “significant nexus” to nearby regulated waters should be considered protected.
  • The court ruled unanimously in favor of the Sacketts, though split 5-4 in reasoning for the decision.
  • Chief Justice John Roberts and Justices Clarence Thomas, Neil Gorsuch and Amy Coney Barrett all joined Alito's majority opinion.

Justice Elena Kagan wrote in a concurring opinion that the court — through its recent rulings on the Clean Water Act and Clean Air Act — has appointed "itself as the national decision-maker on environmental policy" and has not allowed the laws to work as Congress intended them to.

  • "Because that is not how I think our Government should work—more, because it is not how the Constitution thinks our Government should work—I respectfully concur in the judgment only," she wrote.

In another concurring opinion, Justice Brett Kavanaugh wrote that the court was right to throw out the nexus test and rule that the Sackett's property was not a protected wetland, though he disagreed with the court's new "continuous" determination.

  • "By narrowing the Act’s coverage of wetlands to only adjoining wetlands, the Court’s new test will leave some long-regulated adjacent wetlands no longer covered by the Clean Water Act, with significant repercussions for water quality and flood control throughout the United States," Kavanaugh wrote.
  • Justice Clarence Thomas also delivered a concurring opinion.

EPA Administrator Michael Regan said in a statement on Thursday that the court's decision "erodes longstanding clean water protections."

  • “As a public health agency, EPA is committed to ensuring that all people, regardless of race, the money in their pocket, or community they live in, have access to clean, safe water," Regan said. "We will never waver from that responsibility."

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