On December 30, 2022, the U.S. Environmental Protection Agency (EPA) and the U.S. Army Corps of Engineers (collectively Agencies) announced the issuance of a final rule defining “waters of the United States” (WOTUS), a key term in the Clean Water Act (CWA). That phrase, which serves as the definition for “navigable waters” in the statute, effectively establishes the boundaries of the Agencies’ regulatory authority under the CWA. The rule was published in the Federal Register on January 18, 2023, and will take effect 60 days thereafter.

In explaining the underlying basis for the new rule, the Agencies stated they “used the familiar, pre-2015 [WOTUS] definition as a foundation because it has supported decades of clean water progress[.]” It was further stated that “[c]hanging regulatory definitions due to court decisions and final rules issued by the agencies in 2015, 2019, and 2020 have caused uncertainty that harmed communities and our nation’s waters.”

The final rule includes eight CWA exclusions as part of the text. Prior-converted croplands are exempt and EPA adopted USDA’s definition of the term to exclude wetlands converted to croplands prior to Dec. 23, 1985. The remaining seven exclusions written in the new rule include waste treatment systems, ditches, artificially irrigated areas, artificial lakes or ponds, artificial reflecting pools, or swimming pools, water-filled depressions, and swales and erosional features.

The agency also writes that the final rule relies on the longstanding approach of applying two standards to determine jurisdiction for tributaries, adjacent wetlands, and additional waters. “Certain types of waters are jurisdictional under the final rule if they meet either the relatively permanent standard or significant nexus standard.

• Relatively Permanent is a test that provides important efficiencies and clarity for regulators and the public by readily identifying a subset of waters that will virtually always significantly affect paragraph (a)(1) waters. To meet the relatively permanent standard, the waterbodies must be relatively permanent, standing, or continuously flowing waters connected to paragraph (a)(1) waters or waters with a continuous surface connection to such relatively permanent waters or to paragraph (a)(1) waters.
• Significant Nexus is a test that clarifies if certain waterbodies, such as tributaries and wetlands, are subject to the Clean Water Act based on their connection to and effect on larger downstream waters that Congress fundamentally sought to protect. A significant nexus exists if the waterbody (alone or in combination) significantly affects the chemical, physical, or biological integrity of traditional navigable waters, the territorial seas, or interstate waters.”

The significant nexus standard has been one of the most controversial aspects of the definition. During the 2015 effort to revise the definition, it was argued that this definition could allow the connection of much smaller waterways or tributaries, potentially even dry land features.

The new definition also affects adjacent wetlands, defining them as “next to, abutting, or near other jurisdictional waters or behind certain natural or constructed features. They are most often within a few hundred feet of jurisdictional waters. Adjacent wetlands are jurisdictional if they meet either the relatively permanent standard or the significant-nexus standard, or where the wetland is adjacent to a traditional navigable water, the territorial seas, or an interstate water.”

Opponents have argued that revising the definition while the U.S. Supreme Court is reviewing EPA’s jurisdiction under the Clean Water Act is premature. In the case, Sackett v. Environmental Protection Agency, the Sacketts argue for a definition of “adjacent wetlands” even narrower than in the Trump Administration’s 2020 rule. As a result, the governors of 25 states asked the administration to delay the implementation of the rule until after a key Clean Water Act ruling in the Sackett case is issued sometime this spring, they called the Biden administration’s new waters of the U.S. rule confusing and costly to communities.

The governors write: “We call into question the timing and necessity of the rule with the Court’s upcoming Sackett decision which is expected by June of this year. That opinion could significantly impact the final rule and its implementation. To change the rule multiple times in six months is an inefficient and wasteful use of State and federal resources and will impose an unnecessary strain on farmers, builders, and every other impacted sector of the American economy.”

The January 30, 2023 letter to President Biden was signed by the governors of Idaho, Alabama, Alaska, Arkansas, Florida, Georgia, Indiana, Iowa, Mississippi, Missouri, Montana, Nebraska, Nevada, New Hampshire, North Dakota, Ohio, Oklahoma, South Carolina, South Dakota, Tennessee, Texas, Utah, Virginia, West Virginia, and Wyoming.

Not to be left out, members in both houses of Congress introduced a joint resolution of disapproval under the Congressional Review Act (CRA) on February 2, 2023. The House Joint Resolution was introduced by Committee on Transportation and Infrastructure Chairman Sam Graves (R-MO) and Water Resources and Environment Subcommittee Chairman David Rouzer (R-NC) and approximately 150 other members of Congress. If enacted, the resolution would terminate the Biden WOTUS rulemaking utilizing the CRA, which provides a mechanism for Congress to overturn certain final agency actions. An identical measure was also introduced in the Senate on February 2, 2023, by 49 senators, led by Environment and Public Works Ranking Member Shelley Moore Capito (R-WV).

Additional challenges are expected as the implementation date approaches.