December 21, 2021

EPA, Army Corps Release Proposed Rule Redefining “Waters of the United States” Under the Clean Water Act


On December 7, 2021, the Environmental Protection Agency (EPA) and the Department of the Army, Corps of Engineers (Army Corps), published a Proposed Rule to define the scope of waters covered by the Clean Water Act. The widely expected proposal follows upon the announcement by the agencies in June of this year to overturn the 2020 Navigable Waters Protection Rule enacted by the prior Administration.

The agencies’ announcement provided the following background for the proposal:

Congress enacted the Clean Water Act in 1972 with the statutory objective “to restore and maintain the chemical, physical, and biological integrity of the Nation’s waters.” One of the Act’s principal tools in achieving that objective is a prohibition on the discharge of pollutants from a point source to “navigable waters” unless otherwise authorized under the Act. “Navigable waters” are defined in the Act as “the waters of the United States, including the territorial seas.” Thus, “waters of the United States” (WOTUS) is a threshold term establishing the geographic scope of federal jurisdiction under the Clean Water Act. The term “waters of the United States” is not defined by the Act but has been defined by EPA and the Army in regulations since the 1970s and jointly implemented in the agencies’ respective programmatic activities.

The new proposal marks the latest twist in a back-and-forth regulatory drama that, in its latest iteration, dates back to the Administration of President Barack Obama. In 2015 the Clean Water Rule was enacted, which included in the scope of the Act’s coverage those waters with a “significant nexus” to navigable waters. The 2015 rule was enjoined[1] prior to taking effect, and was subsequently repealed in 2019. Thereafter, the Administration of President Donald Trump enacted its own rule, the Navigable Waters Protection Rule, which limited the scope of the Act to a set of defined “jurisdictional” waters while eliminating the “significant nexus” test. This rule was subsequently vacated by a federal district court, leading the agencies to announce that they were halting “implementation of the Navigable Waters Protection Rule nationwide and are interpreting ‘waters of the United States’ consistent with the pre-2015 regulatory regime.”[2]

The Proposed Rule generally adheres to the “waters of the United States” definition that existed prior to the 2015 Clean Water Rule and which dates to 1986. Under the proposal the term includes:

“Traditional navigable waters, interstate waters, and the territorial seas, and their adjacent wetlands; most impoundments of ‘waters of the United States’; tributaries to traditional navigable waters, interstate waters, the territorial seas, and impoundments that meet either the relatively permanent standard or the significant nexus standard; wetlands adjacent to impoundments and tributaries, that meet either the relatively permanent standard or the significant nexus standard; and ‘other waters’ that meet either the relatively permanent standard or the significant nexus standard.”

Under the proposal the ‘‘significant nexus standard’’ covers waters that “either alone or in combination with similarly situated waters in the region, significantly affect the chemical, physical, or biological integrity of traditional navigable waters, interstate waters, or the territorial seas (defined as the ‘foundational waters’).” The agencies seek comment on the “similarly situated,” “region,” and the types of functions that should be analyzed for purposes of the “significant nexus” test.

In contrast to the Navigable Waters Protection Rule, the proposal does not eliminate “ephemeral streams” from CWA coverage, and likely portends greater coverage for wetlands.

The Proposed Rule is open for comment until February 7, 2022, and the agencies have announced public hearings on the rule on January 12, 13, and 18. Once final the new proposal is likely to face its own legal challenges, and the definition of Waters of the United States will likely remain a point of contention.

Jordan Ramis attorneys stand ready to help those interested in participating in the comment process, or better understanding the proposal and its likely impacts.

Gregory Zerzan is an attorney with Jordan Ramis PC. Zerzan has served in a wide range of roles in the U.S. government, including as Acting Assistant Secretary of the U.S. Treasury; Counsel to the House Committees on Agriculture, Financial Services, and Energy and Commerce; and as Principal Deputy Solicitor of the U.S. Department of the Interior. Contact him at or (503)-598-7070.

[1] North Dakota v. U.S. Environmental Protection Agency, No. 3:15-cv-00059 (D.N.D. Aug.

27, 2015)

[2] For more information see the recent update U.S. Army Corp of Engineers Halts Some Permit Applications by Jordan Ramis Shareholder Elizabeth Rosso.

Tags: Water, Agriculture, Local Governments and Special Districts

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