Thomas, J., concurring
Court leaves off.
I
The CWA’s jurisdictional terms have a long pedigree and are bound up with Congress’ traditional authority over the channels of interstate commerce. Solid Waste Agency of Northern Cook Cty. v. Army Corps of Engineers, 531 U. S. 159, 168, and n. 3, 172, 173–174 (2001) (SWANCC). That traditional authority was limited in two ways. First, the water had to be capable of being used as a highway for interstate or foreign commerce. Second, Congress could regulate such waters only for purposes of their navigability—by, for example, regulating obstructions hindering navigable capacity. By the time of the CWA’s enactment, the New Deal era arguably had relaxed the second limitation; Congress could regulate navigable waters for a wider range of purposes. But, critically, the statutory terms “navigable waters,” “navigable waters of the United States,” and “waters of the United States” were still understood as invoking only Congress’ authority over waters that are, were, or could be used as highways of interstate or foreign commerce. The CWA was enacted, and must be understood, against that key backdrop.
A
As the Court correctly states, “land and water use lies at the core of traditional state authority.” Ante, at 23; see also ante, at 2. Prior to Independence, the Crown possessed sovereignty over navigable waters in the Colonies, sometimes held in trust by colonial authorities. See R. Adler, The Ancient Mariner of Constitutional Law: The Historical, Yet Declining Role of Navigability, 90 Wash. U. L. Rev. 1643, 1656–1659 (2013); R. Walston, The Federal Commerce and Navigation Powers: Solid Waste Agency of Northern Cook County’s Undecided Constitutional Issue, 42 Santa Clara L. Rev. 699, 721 (2002) (Walston). Upon Independence, this
