Opinion of the Court
water connected to traditional interstate navigable waters and, second, wetlands with such a close physical connection to those waters that they were “as a practical matter indistinguishable from waters of the United States.” Id., at 742, 755 (emphasis deleted). Four Justices would have deferred to the Government’s determination that the wetlands at issue were covered under the CWA. Id., at 788 (Stevens, J., dissenting). Finally, one Justice concluded that jurisdiction under the CWA requires a “significant nexus” between wetlands and navigable waters and that such a nexus exists where “the wetlands, either alone or in combination with similarly situated lands in the region, significantly affect the chemical, physical, and biological integrity” of those waters. Id., at 779–780 (Kennedy, J., concurring in judgment).
In the decade following Rapanos, the EPA and the Corps issued guidance documents that “recognized larger grey areas and called for more fact-intensive individualized determinations in those grey areas.”[1] As discussed, they instructed agency officials to assert jurisdiction over wetlands “adjacent” to non-navigable tributaries based on fact-specific determinations regarding the presence of a significant nexus. 2008 Guidance 8. The guidance further advised officials to make this determination by considering a lengthy list of hydrological and ecological factors. Ibid. Echoing what they had said about the migratory bird rule, the agencies later admitted that “almost all waters and wetlands across the country theoretically could be subject to a case-specific jurisdictional determination” under this guidance. 80 Fed. Reg. 37056 (2015); see, e.g., Hawkes Co., 578 U. S., at 596 (explaining that the Corps found a significant nexus between wetlands and a river “some 120 miles
- ↑ N. Parrillo, Federal Agency Guidance and the Power To Bind: An Empirical Study of Agencies and Industries, 36 Yale J. on Reg. 165, 231 (2019); see 2007 Guidance 7–11; EPA & Corps, Clean Water Act Jurisdiction Following the U. S. Supreme Court’s Decision in Rapanos v. United States & Carabell v. United States 8–12 (2008) (2008 Guidance).
