The Supreme Court just shriveled federal protection for wetlands, leaving many of these valuable ecosystems at risk

Many ecologically important wetlands, like these in Kulm, N.D., lack surface connections to navigable waterways. USFWS Mountain-Prairie/Flickr, CC BY

The U.S. Supreme Court has ruled in Sackett v. EPA that federal protection of wetlands encompasses only those wetlands that directly adjoin rivers, lakes and other bodies of water. This is an extremely narrow interpretation of the Clean Water Act that could expose many wetlands across the U.S. to filling and development.

Under this keystone environmental law, federal agencies take the lead in regulating water pollution, while state and local governments regulate land use. Wetlands are areas where land is wet for all or part of the year, so they straddle this division of authority.

Swamps, bogs, marshes and other wetlands provide valuable ecological services, such as filtering pollutants and soaking up floodwaters. Landowners must obtain permits to discharge dredged or fill material, such as dirt, sand or rock, in a protected wetland.

This can be time-consuming and expensive, which is why the Supreme Court’s ruling on May 25, 2023, will be of keen interest to developers, farmers and ranchers, along with conservationists and the agencies that administer the Clean Water Act – namely, the Environmental Protection Agency and the U.S. Army Corps of Engineers.

For the last 45 years – and under eight different presidential administrations – the EPA and the Corps have required discharge permits in wetlands “adjacent” to water bodies, even if a dune, levee or other barrier separated the two. The Sackett decision upends that approach, leaving tens of millions of acres of wetlands at risk.

The U.S. has lost more than half of its original wetlands, mainly due to development and pollution.

The Sackett case

Idaho residents Chantell and Mike Sackett own a parcel of land located 300 feet from Priest Lake, one of the state’s largest lakes. The parcel once was part of a large wetland complex. Today, even after the Sacketts cleared the lot, it still has some wetland characteristics, such as saturation and ponding in areas where soil was removed. Indeed, it is still hydrologically connected to the lake and neighboring wetlands by water that flows at a shallow depth underground.

In preparation to build a house, the Sacketts had fill material placed on the site without obtaining a Clean Water Act permit. The EPA issued an order in 2007 stating that the land contained wetlands subject to the law and requiring the Sacketts to restore the site. The Sacketts sued, arguing that their property was not a wetland.

In 2012, the Supreme Court held that the Sacketts had the right to challenge EPA’s order and sent the case back to the lower courts. After losing below on the merits, they returned to the Supreme Court with a suit asserting that their property was not federally protected. This claim in turn raised a broader question: What is the scope of federal regulatory authority under the Clean Water Act?

Housing encroaches on Caloosahatchee River wetlands in Fort Myers, Fla.
Jeffrey Greenberg/Universal Images Group via Getty Images

What are ‘waters of the United States’?

The Clean Water Act regulates discharges of pollutants into “waters of the United States.” Lawful discharges may occur if a pollution source obtains a permit under either Section 404 of the act for dredged or fill material, or Section 402 for other pollutants.

The Supreme Court has previously recognized that the “waters of the United States” include not only navigable rivers and lakes, but also wetlands and waterways that are connected to navigable bodies of water. But many wetlands are not wet year-round, or are not connected at the surface to larger water systems. Still, they can have important ecological connections to larger water bodies.

In 2006, when the court last took up this issue, no majority was able to agree on how to define “waters of the United States.” Writing for a plurality of four justices in U.S. v. Rapanos, Justice Antonin Scalia defined the term narrowly to include only relatively permanent, standing or continuously flowing bodies of water such as streams, oceans, rivers and lakes. Waters of the U.S., he contended, should not include “ordinarily dry channels through which water occasionally or intermittently flows.”

Acknowledging that wetlands present a tricky line-drawing problem, Scalia proposed that the Clean Water Act should reach “only those wetlands with a continuous surface connection to bodies that are waters of the United States in their own right.”

In a concurring opinion, Justice Anthony Kennedy took a very different approach. “Waters of the U.S.,” he wrote, should be interpreted in light of the Clean Water Act’s objective of “restoring and maintaining the chemical, physical, and biological integrity of the Nation’s waters.”

Accordingly, Kennedy argued, the Clean Water Act should cover wetlands that have a “significant nexus” with navigable waters – “if the wetlands, either alone or in combination with similarly situated lands in the region, significantly affect the chemical, physical, and biological integrity of other covered waters more readily understood as ‘navigable.’”

Neither Scalia’s nor Kennedy’s opinion attracted a majority, so lower courts were left to sort out which approach to follow. Most applied Kennedy’s significant nexus standard, while a few held that the Clean Water Act applies if either Kennedy’s standard or Scalia’s is satisfied.

Regulators have also struggled with this question. The Obama administration incorporated Kennedy’s “significant nexus” approach into a 2015 rule that followed an extensive rulemaking process and a comprehensive peer-reviewed scientific assessment. The Trump administration then replaced the 2015 rule with a rule of its own that largely adopted the Scalia approach.

The Biden administration responded with its own rule defining waters of the United States in terms of the presence of either a significant nexus or continuous surface connection. However, this rule was promptly embroiled in litigation and will require reconsideration in light of Sackett v. EPA.

The Sackett decision and its ramifications

The Sackett decision adopts Scalia’s approach from the 2006 Rapanos case. Writing for a five-justice majority, Justice Samuel Alito declared that “waters of the United States” includes only relatively permanent, standing or continuously flowing bodies of water, such as streams, oceans, rivers, lakes – and wetlands that have a continuous surface connection with and are indistinguishably part of such water bodies.

None of the nine justices adopted Kennedy’s 2006 “significant nexus” standard. However, Justice Brett Kavanaugh and the three liberal justices disagreed with the majority’s “continuous surface connection” test. That test, Kavanaugh wrote in a concurrence, is inconsistent with the text of the Clean Water Act, which extends coverage to “adjacent” wetlands – including those that are near or close to larger water bodies.

“Natural barriers such as berms and dunes do not block all water flow and are in fact evidence of a regular connection between a water and a wetland,” Kavanaugh explained. “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.”

The majority’s ruling leaves little room for the EPA or the Army Corps of Engineers to issue new regulations that could protect wetlands more broadly.

The court’s requirement of a continuous surface connection means that federal protection may no longer apply to many areas that critically affect the water quality of U.S. rivers, lakes and oceans – including seasonal streams and wetlands that are near or intermittently connected to larger water bodies. It might also mean that construction of a road, levee or other barrier separating a wetland from other nearby waters could remove an area from federal protection.

Congress could amend the Clean Water Act to expressly provide that “waters of the United States” includes wetlands that the court has now stripped of federal protection. However, past efforts to legislate a definition have fizzled, and today’s closely divided Congress is unlikely to fare any better.

Whether states will fill the breach is questionable. Many states have not adopted regulatory protections for waters that are outside the scope of “waters of the United States.” In many instances, new legislation – and perhaps entirely new regulatory programs – will be needed.

Finally, a concurring opinion by Justice Clarence Thomas hints at potential future targets for the court’s conservative supermajority. Joined by Justice Neil Gorsuch, Thomas suggested that the Clean Water Act, as well as other federal environmental statutes, lies beyond Congress’ authority to regulate activities that affect interstate commerce, and could be vulnerable to constitutional challenges. In my view, Sackett v. EPA might be just one step toward the teardown of federal environmental law.

This is an update of an article originally published on Sept. 26, 2022.

Albert C. Lin was a trial attorney for the Environment and Natural Resources Division of the U.S. Department of Justice from 1998 to 2003. He served as a law clerk to the Honorable Merrick Garland of the U.S. Court of Appeals for the D.C. Circuit and to the Honorable James Browning of the U.S. Court of Appeals for the Ninth Circuit.