Sackett v. EPA: Wetlands Aren’t “Waters”

By Anna-Maria Marshall, Associate Professor of Sociology and Law at University of Illinois

Michael and Chantell Sackett were developers who bought a piece of “soggy” property in Idaho near Priest Lake, a popular vacation destination. To prepare to build a house, they filled the lot with gravel until a neighbor complained to the EPA, which ordered the Sacketts to stop the work and to return the property to the condition they found it. The EPA reasoned that the Sackett property was a wetland, connected to the nearby lake and therefore subject to EPA’s regulations governing the “waters of the United States” covered by the Clean Water Act. The case was litigated for 14 years until the Supreme Court finally ruled in favor of the Sacketts in May 2023. In that ruling, the Supreme Court largely ignored the science of hydrology and in doing so, severely restricted the power of the EPA to regulate wetlands.

The Clean Water Act gives the EPA the power to regulate the “waters of the United States.” That phrase is intentionally vague, as legislators recognize that they are not hydrologists and that such definitions are best left to the experts. If defined too broadly, then the EPA would have the power to regulate every largish puddle that appears after a heavy rainfall. On the other hand, if it is defined too narrowly, the CWA would lose its “teeth,” putting sources of water pollution beyond the reach of regulation. Thus, defining the scope of the “waters of the US” has been a contentious issue in the federal courts for many years.

The Supreme Court has attempted to shape this definition several times. The last time, in the 2006 case Rapanos v. United States, the Court asked whether wetlands were “waters of the United States” but could not arrive at a single standard. Justice Antonin Scalia advocated for a pro-business position: the waters of the US were confined to navigable waters and to be regulated, other waterways had a continuous surface connection to those navigable waters. However, Justice Anthony Kennedy articulated a definition that reflected a more scientific understanding about the way that water moves across a landscape. Kennedy said that the question for courts and the EPA should be whether there was “a significant nexus” (that is, a connection) between the wetland and an “adjacent” body of water that was already protected by the CWA. While there was no clear majority on the Court for either legal test, the federal courts have followed Kennedy’s “significant nexus” test. The EPA under both Bush and Obama also embraced Kennedy’s interpretation; the EPA’s rules about jurisdiction over navigable bodies of water and all streams, ponds, lakes, and wetlands “adjacent” to those waters.

In Sackett v EPA decided this year, the Supreme Court revisited the question of whether the EPA’s jurisdiction extended to wetlands, focusing on the meaning of the word “adjacent.” All 9 justices agreed that the EPA had exceeded its authority by trying to regulate the Sackett’s soggy patch of property, but they were sharply divided about why. The 4 dissenting justices thought that under the EPA’s existing rules, the Sackett property did not have a significant nexus to the nearby Priest Lake. The majority, however, led by Justice Samuel Alito, rejected the significant nexus test and existing EPA rules. He argued that the existing rule put property owners in a “precarious position” because determining whether the property was a regulable wetland would require expert guidance and (probably) litigation, making it too expensive to obey the law. Instead of following scientific guidance about the water in wetlands, Alito turned to Random House and Webster’s dictionaries for the meaning of “adjacent.” Those sources told him that “adjacent” means “adjoining” or “neighboring,” leading him and a majority of the Court to conclude “Wetlands that are separate from traditional navigable waters cannot be considered part of those waters, even if they are located nearby.” Thus, the Supreme Court vacated the EPA’s regulatory authority over wetlands that are not visibly connected to another regulable body of water.

The Supreme Court’s opinion in Sackett raises questions about the role of science in the nation’s regulatory systems. Courts once deferred to scientific expertise, especially when relied upon by administrative agencies. By substituting dictionary definitions for hydrological sciences, the Court has signaled that such deference could be coming to an end. Moreover, the Sackett case will have a dramatic effect on the EPA’s regulatory approach to regulating wetlands in particular and in its power to enforce the Clean Water Act more broadly. Unmonitored wetlands could become the source of nutrient and other pollution in rivers and lakes, compromising drinking water and recreational activities across the country.

Opinions expressed here do not necessarily reflect those of the Sustainable Phosphorus Alliance.