Today the U.S. Environmental Protection Agency and U.S. Army Corps of Engineers released their released a final rule revising the federal definition of "waters of the United States"(aka "WOTUS"), which defines the scope of federal regulation under the Clean Water Act. This rule is less expansive than the WOTUS definition promulgated by the Obama Administration, but more expansive than adopted by the Trump Administration.
The CWA prohibits the discharge of pollutants in the navigable waters of the United States. The CWA further defines "navigable waters" as "the waters of the United States." This new rule, in turn, adopts a regulatory definition of "waters of the United States."
The new rule covers all waters and wetlands with a continuous surface connections with navigable waters, as well as those waters and wetlands which, "either alone or in combination with similarly situated waters in the region, significantly affect the chemical, physical, or biological integrity" of navigable waters. The legal question is whether this definition extends the agencies' authority beyond that which is auhtorized by the CWA, or extends beyond the scope of Congress' power under the Commerce Clause, which (combined with the Necessary and Proper Clause) allows the federal government to regulate that which "subtantially affects" interstate commerce.
