The Clean Water Act might not prevent building on them.
The federal government does not have the power to reach far upstream to protect every ditch and wetland in a watershed.
In a ruling restricting federal authority to protect the environment, the US Supreme Court on Monday said the reach of federal regulators under the Clean Water Act is limited. But the high court's nine justices were unable to reach majority agreement about how and where to draw those limits.
The result is a decision best described as 4-1-4. Four justices agreed that the law called for a restrictive view of the scope of federal jurisdiction to reach remote wetlands. Four other justices concluded that the statute permits the government to take upstream actions to prevent downstream degradation of federal water resources.
At dead center of the court sits Justice Anthony Kennedy, who provided the critical fifth vote on the restrictive side of the case. That action sends the two consolidated cases back to the lower courts where judges must divine a coherent approach to federal jurisdiction from the high court's splintered decision.
"It is unfortunate that no opinion commands a majority of the court on precisely how to read Congress' limits on the reach of the Clean Water Act," writes Chief Justice John Roberts in a concurrence on the restrictive side of the case. "Lower courts and regulated entities will now have to feel their way on a case-by-case basis."
The decision is a setback for environmentalists seeking to push tough federal regulations to the broadest possible swath of threatened wetlands.
"It is a defeat, absolutely," says Jim Murphy, wetlands counsel at the National Wildlife Federation. "It really places practical burdens on regulation and it also makes it more difficult for holistic watershed approaches to be used to really protect all the small waters that collectively have huge water quality implications."
The decision marks a partial victory for developers and other landowners who believe state and local government – not federal bureaucrats – should decide how local land is developed.
The opinion relates to two cases from Michigan that were consolidated for oral argument on Feb. 21. The cases are Carabell v. US Army Corps of Engineers, and Rapanos v. United States.