The United States Supreme Court handed the Environmental Protection Agency a defeat in a unanimous ruling over the scope of waterways covered under the Clean Water Act.
The ruling comes in a case filed by Michael and Chantell Sackett, who sued the EPA after the agency stopped them from building a home on their property because it was too close to wetlands the EPA claimed authority to regulate.
In a 9-0 ruling, the Justices agreed that the EPA overstepped its bounds and ruled in favor of the Sacketts. However, the Justices were split 5-4 on how to define what bodies of water the EPA has authority over.
Writing for the majority, Justice Samuel Alito ruled that the EPA can only regulate bodies of water if they have a "continuous surface connection" to major bodies of water.
"Understanding the CWA to apply to wetlands that are distinguishable from otherwise covered 'waters of the United States' would substantially broaden [existing statute] to define 'navigable waters' as 'waters of the United States and adjacent wetlands,'" Alito wrote.
Justice Brett Kavanaugh wrote a second opinion, saying that while he agreed with the merits of the case, he did not agree with the majority's opinion to redefine what waters are subject to the Clean Water Act. He warned their decision could have "significant repercussions for water quality and flood control throughout the United States."
Kavanaugh was joined by Justices Sonia Sotomayor, Elena Kagan, and Ketanji Brown Jackson.