September 01, 2021

The Latest Chapter in the Waters of the US Saga

3 min

On August 30, 2021, District Court Judge Rosemary Marquez from the District of Arizona authored the latest chapter in the lengthy "waters of the United States" (WOTUS) saga, when she issued an order reversing major changes to the WOTUS definition made by the Trump administration in 2020.

The CWA regulates the discharge of pollutants from point sources into "navigable waters." The CWA defines "navigable waters" as "waters of the United States, including the territorial seas." The meaning of WOTUS has been the subject of protracted debate and litigation for decades.

In 2015, the Obama administration promulgated the Clean Water Rule, which redefined "waters of the United States" to include certain waters with a significant nexus to traditionally navigable waters, following Justice Kennedy's analysis in Rapanos v. United States, 547 U.S. 715 (2006). In October 2019, the Trump administration repealed the 2015 Clean Water Rule and, in April 2020, promulgated the Navigable Waters Protection Rule (NWPR), which itself redefined "waters of the United States" to be consistent with Justice Scalia's plurality opinion in Rapanos, excluding certain waters from the definition, such as ephemeral streams.

In the Arizona litigation, Pasqua Yaqui Tribe v. EPA, the plaintiffs asked the court to vacate the 2020 NWPR and remand the rule back to the EPA and the Army Corps. The EPA and the Corps also sought voluntary remand (although the agencies did not seek vacatur of the NWPR). In its ruling, the Court sided with the plaintiffs, vacating the NWPR and remanding the rule back to the agencies for reconsideration.

The Court noted that when promulgating the NWPR, the government made several significant errors that could not be easily remedied with just additional procedure. For example, the Court noted that the NWPR disregarded "established science and the advice of the Agencies' own experts." The Court also concluded that keeping the NWPR in force "would risk serious environmental harm," noting that more than 300 projects that would have required CWA permitting before the enactment of the NWPR no longer required permitting.

The Court concluded that "[t]he seriousness of the Agencies' errors in enacting the NWPR, the likelihood that the Agencies will alter the NWPR's definition of 'waters of the United States,' and the possibility of serious environmental harm if the NWPR remains in place upon remand, all weigh in favor of remand with vacatur."

Finally, the Court concluded that vacating the NWPR did not pose an unjustifiable risk of regulatory uncertainty, stating that "[t]he pre-2015 regulatory regime is familiar to the Agencies and industry alike, and the Agencies have expressed an intent to repeal the NWPR and return to the pre-2015 regulatory regime while working on a new definition of 'waters of the United States,' [and the] consequences of an interim change do not support the unusual remedy of remand without vacatur."

As the court applied Ninth Circuit precedent concerning regulatory vacatur, it remains to be seen how far-reaching this analysis will be. There certainly is no shortage of cases where plaintiffs have sought vacatur on various Trump-era environmental rules, even with assurances from the Biden administration that new rules were being proposed in their stead. With respect to the WOTUS rule, however, this recent decision does have nationwide impact.

Venable will continue to track the latest developments in the WOTUS journey, including the most recent regulatory actions this summer, when the EPA and the Corps announced their intention to again revise the "waters of the United States" definition, and followed up with an announcement that the EPA would be providing a series of engagement opportunities, including an opportunity for stakeholders and the public to provide written recommendations about the definition.

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