Clean Water Act Definition for Waters of the United States Vacated After Challenge From Tribes


The District of Arizona ruled in favor of six tribes in a challenge to Clean Water Act rules, specifically the definition of “waters of the United States” and whether wetlands are included in the definition, ruling to remand and vacate the definition. 

Pascua Yaqui Tribe, Quinault Indian Nation, Fond du Lac Band of Lake Superior Chippewa, Menominee Indian Tribe of Wisconsin, Tohono O’Odham Nation, and Bad River Band of Lake Superior Chippewa challenged two final rules in their lawsuit filed against the U.S. Environmental Protection Agency and the U.S. Army Corps of Engineers. 

One of the rules defined “waters of the United States” in pre-existing rules and repealed the 2015 Clean Water Rule. The second rule, the Navigable Waters Protection Rule (NWPR), specifically re-defined waters of the United States in the Clean Water Act. These rules determine which waters are protected under the Clean Water Act, and the plaintiffs purported that under the definition the bodies of water they use were not being sufficiently protected which caused harm to their tribes. 

The defendants reportedly did not file a response to the plaintiffs’ motion for summary judgment, instead asking for the NWPR to be voluntarily remanded to them for reconsideration without vacatur. The plaintiffs agreed with the motion to remand the NWPR, but argued that it should be vacated on remand. A hearing on the issue was held on August 4, leading the court to determine that it would grant the motion for remand, but with the vacatur that the plaintiffs requested. 

The defendants were reportedly working on developing a regulatory definition for “waters of the United States,” and had given notice that pursuant to an executive order from President Joe Biden they intended to restore the definition that was used before the 2015 Clean Water Rule. 

The plaintiffs argued that the vacatur was necessary in order to “prevent irreversible harms.” The court agreed with the plaintiffs, and concluded that equity in this instance did not demand that it be remanded without vacatur. 

The order explained that the concerns with the rule “are not mere procedural errors or problems that could be remedied through further explanation … rather they involve fundamental, substantive flaws that cannot be cured without revising or replacing the NWPR’s definition of ‘waters of the United States.’” 

The plaintiffs are represented by Earthjustice and the defendants by the U.S. Department of Justice.