This week, the Tenth Circuit Court of Appeals held that the Navigable Waters Protection Rule (NWPR) issued by the Trump administration redefining what waters are protected by the federal Clean Water Act must now be enforced in Colorado.  Until the ruling, Colorado was the only state in the country where the NWPR was not being implemented since becoming effective in June 2020.  Though the NWPR is now the law of the land in Colorado, the Tenth Circuit did not address the underlying legality of the NWPR or clarify ongoing uncertainty regarding the jurisdictional scope of the Clean Water Act.

The Tenth Circuit’s decision overruled U.S. District Judge William Martinez’s ruling granting the State of Colorado’s request for a preliminary injunction that stayed the effective date of the NWPR pending the court’s decision on the merits of the case.  Along with numerous other plaintiffs nationwide, Colorado challenged the NWPR in May 2020, arguing that it unlawfully narrows the definition “waters of the United States” under the Clean Water Act.  The NWPR excludes categories of waters that were previously protected by the Act, including certain wetlands and ephemeral and intermittent streams, which account for a majority of Colorado’s stream miles. 

Colorado requested that the Tenth Circuit affirm the lower court’s ruling that enjoined the NWPR because the state had demonstrated irreparable harm from the rule.  Like most states, Colorado relies on the federal Environmental Protection Agency and Army Corps of Engineers to regulate discharges of dredged and fill material in waters covered by the Clean Water Act.  Colorado argued that the rule leaves a significant portion of the state’s waters without federal protection and would impose a significant burden on the state by forcing it to establish its own regulatory program for dredge and fill activities in state waters unprotected under the NWPR.  Without any existing state program, Colorado contended that the NWPR created a “permitting gap” that  would lead to the unmitigated discharge of fill in waters no longer federally-protected, resulting in significant environmental harm.

The Tenth Circuit rejected Colorado’s argument of irreparable harm and held that the lower court abused its discretion by blocking the implementation of the NWPR in the state.  The court found insufficient evidence of any enforcement burden on the state and concluded that it was “pure speculation” to conclude that the NWPR’s narrowing of waters protected by Clean Water Act would lead to more illegal fill activities in Colorado.  The Tenth Circuit reversed and remanded the lower court’s decision based solely on Colorado’s failure to show harm and without addressing other preliminary injunction factors, including the likelihood of Colorado’s success on the merits.

Though the lower court’s stay of the NWPR had gained national attention, the Tenth Circuit’s ruling did little to help clarify the fate of the NWPR or provide direction for regulated entities that must continue to navigate an unpredictable regulatory landscape.  The NWPR is now effective across the country, but remains subject to numerous legal challenges.  It is also under review by the Biden administration, that does not seem inclined to defend the rule.  The federal agencies had requested that the Tenth Circuit hold the case in abeyance pending the administration’s review of the NWPR, which the court declined to do this week. 

Developers, farmers, and others affected by the NWPR should continue to proceed with caution in planning any activities that may impact waters protected by the NWPR and the substantial amount of state waters now excluded from federal protection.  Colorado also faces uncertainties with the NWPR.  It could pursue legislation establishing its own dredge and fill regulatory program, which failed in the 2020 legislative session, or it may wait to see what regulatory action the Biden administration takes, which will invariably lead to additional legal challenges.

One thing is clear:  uncertainty regarding the meaning of “waters of the United States” will continue in Colorado and beyond for the foreseeable future.

If you have questions regarding the regulation of waters under the Clean Water Act should contact Nate Hunt, Sara Mogharabi, or Sarah Judkins.