Evolution of the Meaning of “Waters of the United States” in the Clean Water Act

Summary

The scope of waters that are properly the subject of federal water pollution legislation has been the subject of long-standing consideration by all three branches of the federal government, particularly in the aftermath of the 1972 amendments to the Federal Water Pollution Control Act, commonly referred to as the Clean Water Act. In a shift from early water pollution legislation, those amendments eliminated the requirement that the federally regulated waters—known as jurisdictional waters—must be navigable in the traditional sense, meaning that they are capable of being used by vessels in interstate commerce. Rather than use classical tests of navigability, the amendments redefined “navigable waters” for purposes of the Clean Water Act’s jurisdiction to include “the waters of the United States, including the territorial seas.” Disputes over the proper meaning of that phrase have been ongoing.

Some courts and commentators also disagree on how the scope of federal jurisdictional waters changed over time as a result of interpretative approaches taken by the federal agencies responsible for administering the Clean Water Act—the Environmental Protection Agency (EPA) and the U.S. Army Corps of Engineers (Corps). While some believe EPA and the Corps consistently expanded the meaning of “waters of the United States,” others contend that, in recent years, the agencies have construed the term in a narrower fashion than permitted under the Clean Water Act. In 2015, the Corps and EPA issued a new rule, known as the Clean Water Rule, that substantially redefined “waters of the United States” in the agencies’ regulations for the first time in more than two decades. Some observers disagree on whether the Clean Water Rule constitutes an expansion of jurisdiction over waters not previously regulated. This report provides context for this debate by examining the history of major changes to the meaning of “waters of the United States” as expressed in federal regulations, legislation, agency guidance, and case law.

The Clean Water Act uses the phrase “waters of the United States,” but it does not include a statutory definition of that term. The long-standing disagreement over the meaning of that phrase has centered on the degree to which the Clean Water Act should be interpreted as covering the widest amount of “waters” that could permissibly be federally regulated under the Constitution, or whether that term should be interpreted in a more limited fashion.

Federal authority to regulate waters within the United States primarily derives from the Commerce Clause, and accordingly, federal laws and regulations concerning waters of the United States cannot cover matters which exceed that constitutional source of authority. During the first two decades after the passage of the Clean Water Act, courts generally interpreted the act as having a wide jurisdictional reach. In recent decades, however, the Supreme Court has emphasized that “the grant of authority to Congress under the Commerce Clause, though broad, is not unlimited.” This modern Commerce Clause jurisprudence has informed federal courts’ approach to interpreting which “waters” are subject to the Clean Water Act.

Most recently, courts have taken up legal challenges to the Clean Water Rule. On October 9, 2015, the United States Court of Appeals for the Sixth Circuit stayed its enforcement, and the House version of the FY2017 Interior-Environment appropriations bill (H.R. 5538) would block its application by prohibiting the use of appropriated funds to implement changes to the meaning of jurisdictional waters beyond those that were in effect on October 1, 2012.