The Volokh Conspiracy

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Clean Water Act

EPA/Army Corps Propose to Formalize Waters of the United States Definition

Perhaps surprisingly, the Biden Administration is not pushing an expansive interpretation of federal regulatory jurisdiction under the Clean Water Act.


Last week, the Environmental Protection Agency and U.S. Army Corps of Engineers proposed the third new definition of "waters of the United States" in the past six years. Unlike the Obama Administration, however, the Biden Administration is taking a modest and somewhat conservative approach that does relatively little to redefine the scope of federal regulatory jurisdiction under the Clean Water Act, perhaps with an eye toward eventual Supreme Court review.

The new EPA/Army Corps proposed rule is basically a revision of the pre-2015 regulatory definition that seeks to account for the Supreme Court's decisions in SWANCC v. U.S. Army Corps and Rapanos v. United States. In this respect, the rule is something the Army Corps and EPA could have (and likely should have) done long ago. It is also likely to be significantly less vulnerable to legal challenge than was the Obama Administration's so-called WOTUS rule (or the Trump Administration's replacement).

The biggest change to the regulations is to replace the pre-2015 rule's overbroad invocation of federal regulatory authority under the Commerce Clause with language referencing the jurisdictional tests proposed by Justices Scalia and Kennedy in Rapanos. In other words, the EPA and Army Corps seem more interested in providing regulatory certainty and conforming their regulations to relevant judicial opinions than with asserting the broadest regulatory authority possible.

The pre-2015 rule, which had been in place since the mid-1980s, had asserted federal regulatory authority over all waters "the use, degradation or destruction of which could affect interstate or foreign commerce." Such a broad assertion of jurisdiction went far beyond the scope of the federal commerce power—which requires "substantial effects," not merely effects (let alone potential or speculative effects)—and had been rejected in SWANCC and Rapanos. The new rule both rejects this expansive formulation, and aligns itself with the Supreme Court's pronouncements on how the CWA should be interpreted.

The greatest legal vulnerability of the new rule is likely its reliance on Justice Kennedy's Rapanos concurrence. While this opinion defines the outer bounds of federal CWA jurisdiction at the moment, there are reasons to doubt whether the current Supreme Court would embrace as broad a conception of federal regulatory authority. Three of the current justices (Roberts, Alito & Thomas) signed on to Justice Scalia's more narrow plurality, and Justice Kavanaugh seemed to endorse the Scalia approach in his Maui v. Hawaii Wildlife Federation concurrence. On top of that, Justice Gorsuch also embraced a narrow conception of federal regulatory jurisdiction in Maui. So even if Justice Barrett is not inclined to follow her former mentor's approach to the CWA, there may be five votes to make Justice Scalia's plurality the law.

The timing of the new proposed rule is also convenient for the Department of Justice, which will soon be filing a brief opposing certiorari in the Sackett case (which I wrote about here). The Sacketts, represented by the Pacific Legal Foundation, are asking the Court to revisit the scope of CWA jurisdiction and adopt the Scalia Rapanos plurality. One of the stronger arguments for doing so is the continuing uncertainty over the scope of federal regulatory jurisdiction—uncertainty that has swirled for the past fifteen years and has not been helped by the Obama and Trump Administration's efforts to redefine waters in radically different ways and the rough treatment both rules received in federal court.

With the proposal of this new rule, however, the federal government can now argue that the EPA and Army Corps are in the process of adopting a new rule that will increase regulatory certainty and ensure that both agencies adopt sufficiently narrow assertions of regulatory authority to satisfy the courts. Further, DOJ can argue that Supreme Court review of CWA jurisdiction is premature, and should await the finalization of the new rule. Of course, similar arguments did not dissuade the Supreme Court from accepting review of a major clean air act and climate change case, so we will have to see whether the justices find these arguments persuasive here.

Update: As initially posted I inadvertently wrote "increase regulatory uncertainty," instead of "increase regulatory certainty." My bad. This rule, DOJ will argue, will increase regulatory certainty, both by adopting a definition consistent with Supreme Court precedent, as well as by building off the definition that has been in place since the 1980s, instead of adopting a wholly new definition based upon new criteria.