THE CLEAN WATER ACT AT FIFTY: THE EVOLUTION OF THE WATERS OF THE UNITED STATES IN THE CONTEXT OF THE COMMERCE CLAUSE AND RATIONAL BASIS REVIEW

Written by Alec D. Tyra¹

The year 2022 marked the fiftieth anniversary of the passage of the 1972 amendments to the Federal Water Pollution Control Act.²The 1972 amendments would become the foundation of what is commonly called the Clean Water Act (CWA). The primary purpose of CWA, outlined in section 101(a) of the Act, is "to restore and maintain the chemical, physical, and biological integrity of the Nation’s waters." The CWA forms the structure for regulating pollution in "navigable waters." The CWA defines "navigable water" as all bodies of water that are considered "Waters of the United States" (WOTUS).³ The definition of WOTUS, in turn, determines the scope of authority that the Environmental Protection Agency (EPA) and the U.S. Army Corps of Engineers (Army Corps) can exert over section 402 (National Pollutant Discharge Elimination System) permitting and section 404 permitting (discharge of dredged or fill materials into water bodies). However, the CWA does not provide any further definition of which water resources would be considered a WOTUS. This omission has left the EPA, Corps, and the federal judiciary the primary task of interpreting the scope of the term "WOTUS," and ultimately the task of interpreting the jurisdictional scope of one of the nation’s primary environmental statutes.

Throughout the CWA’s fifty year-history, courts and regulators have grappled with defining WOTUS. The CWA has been one of the most litigated environmental statutes with thirty Supreme Court opinions interpreting the statute; Supreme Court jurisprudence spans the Burger Court to the Roberts Court.⁴ One of the most prominent of those opinions is Rapanos v. United States from 2006; at present, the EPA is primed to return to the pre-Rapanos regulatory definition and the application of the "Significant Nexus" test proposed by Justice Anthony Kennedy in his concurrence in that case.⁵ However, Justice Kennedy did not offer a definition or factors to help determine what waters have a "Significant Nexus" to major bodies of water such that they would be considered a WOTUS. For this reason, the "Significant Nexus" test has been criticized for not providing a clear test for regulators to apply in determining if bodies of waters fall under the jurisdiction of the CWA. ⁶

The Significant Nexus test deserves reexamination within the context of historic navigability. In this regard, reexamination of the historic common law interpretation shows that "navigability" is intertwined with the federal power to regulate interstate commerce.⁷ As such, regulation of "navigable waters" should be understood as related to Congress’ express power to regulate commerce, which exists where activity has "substantial effects" on interstate commerce.⁸ By retethering CWA jurisdiction to its historic roots within navigability and commerce, the CWA "Significant Nexus" test is properly understood as rational basis