A federal judge has granted a temporary reprieve for the Gross Reservoir Expansion Project, allowing construction to continue for two more weeks while a legal appeal is considered. The decision, issued on Sunday, offers a short-term stay of an earlier ruling that ordered an immediate halt to the project, which plays a crucial role in providing water to the Denver metro area.

The project, overseen by Denver Water, involves expanding the Gross Reservoir located near Boulder, Colorado. The $531 million effort is intended to increase water storage capacity in response to growing demand, climate change-related droughts, and extreme weather conditions. As of now, construction is approximately 60% complete.

The temporary stay comes just days after U.S. District Court Judge Christine M. Arguello issued a preliminary injunction on Thursday, citing violations of federal environmental law in the approval process. Judge Arguello ruled that the U.S. Army Corps of Engineers failed to comply with required federal standards when it granted the project a permit.

In response to that injunction, Denver Water filed an appeal with the 10th Circuit Court of Appeals and requested the stay to allow construction to resume. The agency emphasized that the project was set to begin seasonal work on April 10 and that halting progress at this stage poses serious risks.

“We view this decision as a radical remedy that should raise alarm bells with the public, not only because of its impacts to water security in an era of longer, deeper droughts, catastrophic wildfire and extreme weather, but because it serves as an egregious example of how difficult it has become to build critical infrastructure in the face of relentless litigation and a broken permitting process,” Denver Water said in a statement on Friday. “In this case, the order is even more appalling with the project so deep into construction.”

The utility further warned that suspending construction could compromise both the safety of the site and the region’s water supply. These concerns were acknowledged by Judge Arguello in her Sunday order granting the two-week stay.

Denver Mayor Mike Johnston also expressed concern over the potential consequences of the injunction. In a statement on Friday, he said, “Denverites, businesses and visitors depend on reliable, clean and safe drinking water every day. The completion of Denver Water’s Gross Reservoir Expansion Project means that Denver and its surrounding communities will have the necessary water security for years to come.”

The Gross Reservoir Expansion has been a point of legal contention for several years. Environmental groups including Save The Colorado, The Environmental Group, WildEarth Guardians, Living Rivers, the Waterkeeper Alliance, and the Sierra Club first filed suit in 2018 to challenge the project’s approval. The plaintiffs argue that the expansion would negatively impact the South Boulder Creek ecosystem and wildlife, and that alternative solutions were not adequately explored.

Opponents of the expansion claim that the project could set a harmful precedent for future water development in the West and that the environmental toll of damming and diverting rivers has not been fully addressed. They point to longstanding concerns about over-allocation of water in the Colorado River Basin, which supplies Gross Reservoir, as a warning that the region's water strategy needs serious reform.

Denver Water maintains that the expansion is necessary to meet future water needs for its 1.5 million customers and that it has followed all required environmental and regulatory steps throughout the process. The agency argues that further delays in construction will not only increase costs but could also prevent the region from being adequately prepared for future droughts.

For now, work can resume — at least temporarily — as the 10th Circuit Court weighs the appeal. The final outcome could have far-reaching implications for both infrastructure development and environmental permitting across the region.

Originally reported by Derek Draplin in The Center Square.