Denver Water vows to take Gross Reservoir Dam expansion fight to the U.S. Supreme Court

Denver Water vowed this week to take the high-stakes battle over a partially built dam in Boulder County to the U.S. Supreme Court if necessary to defend what it sees as its well-established right to continue construction and deliver water to its 1.5 million metro-area customers.

“It would be irresponsible not to do that,” Denver Water’s General Manager Alan Salazar said in an interview Tuesday as a tense month of legal maneuvering continued.

Senior U.S. District Court Judge Christine Arguello on April 3 put a halt to construction of the $531 million Gross Reservoir Dam raise nearly four months after Denver Water and the river-defending nonprofit Save the Colorado failed to negotiate a settlement that would add new environmental protections to the project. When settlement talks stalled, Save the Colorado asked for and was granted an injunction.

This Fresh Water News story is a collaboration between The Colorado Sun and Water Education Colorado. It also appears at wateredco.org/fresh-water-news.

Almost immediately, Denver Water filed for temporary relief from the injunction, saying, in part, that it would be unsafe to stop work as the incomplete concrete walls towered above Gross Reservoir in western Boulder County. 

Arguello granted that request, too.

Now the water agency, the largest utility in the Intermountain West, has filed an emergency request with the federal appeals court, seeking to permanently protect its right to continue construction as the legal battle continues.

A decision could come as early as this week as a 10th Circuit Court of Appeals panel considers Denver Water’s emergency request, according to environmental advocate Gary Wockner. Wockner leads Save The Colorado, a group that has financed and led litigation against Denver Water and many other agencies seeking new dams or river diversions. Wockner said he is ready to continue the fight as well.

“We are prepared to defend the district court’s decision,” Wockner said, referring to the construction halt.

The high-profile dispute erupted in Denver just weeks after Northern Water agreed to a $100 million settlement with Save The Colorado and its sister group, Save The Poudre, to allow construction of the Northern Integrated Supply Project, or NISP, to proceed. 

The money will be used to help restore the Cache la Poudre River, including moving diversion points and crafting new agreements with diverters that will ultimately leave more water in the river. Northern Water, which operates the federally owned Colorado-Big Thompson Project for the U.S. Bureau of Reclamation, is overseeing the permitting and construction of NISP.

But two years of talks and negotiations between Save The Colorado and Denver Water failed to yield a similar environmental settlement over the Gross Reservoir Dam expansion project. It was after the talks failed that Federal District Court Judge Arguello agreed to halt construction on the dam.

Whether a new environmental deal will be forthcoming now isn’t clear. Both sides declined to comment on whether settlement talks had resumed.

Salazar also declined to discuss whether a deal similar to the $100 million NISP settlement would emerge over the Gross Reservoir lawsuit.

“I don’t want to get into the cost of a settlement,” Salazar said. “But the impact on ratepayers would be significant.”

Case sets the stage for future water projects in Colorado

Across the state, water officials are closely watching the case play out.

For fast-growing Parker Water and Sanitation, the preliminary injunction to stop construction, though temporary, is worrisome.

Its general manager, Ron Redd, said he wasn’t sure how his small district, which is planning a major new water project in northeastern Colorado, would cope with a similar injunction or a U.S. Supreme Court battle.

“In everything permitting-wise you need consistency in how you move projects forward,” Redd said. “To have that disrupted causes concern. Is this going to be the new normal going forward? That bothers me.”

Denver Water first moved to raise Gross Dam more than 20 years ago when it began designing the expansion and seeking the federal and state permits required by most water projects. 

After years of engineering, studies and federal and state analyses, construction began in 2022. It has involved taking part of the original dam, built in the 1950s, and raising its height by 131 feet to nearly triple the reservoir’s storage capacity to 119,000 acre-feet from 42,000 acre-feet. An acre-foot of water equals 326,000 gallons, enough to serve up to four urban households each year.

The giant utility has said it needs the additional storage to secure future water supplies as climate change threatens stream flows in its water system, a key part of which lies in the Fraser River, a tributary to the Upper Colorado River in Grand County. The expansion was also necessary to strengthen its ability to distribute water from the northern end of its system, especially if problems emerged elsewhere in the southern part of its distribution area, as occurred during the 2002 drought.

And the judge agreed climate change is a factor but she said it’s not clear the water would ever even materialize as flows shrink. She overturned Denver Water’s permits because she said the Army Corps had not factored in Colorado River flow losses from climate change, and whether Denver would ever actually see the water it plans to store in an expanded Gross. Arguello also ruled the Army Corps had not spent enough time analyzing alternatives to the Gross Reservoir expansion.

Wockner said forcing Denver Water and the U.S. Army Corps of Engineers to re-analyze water projections under new climate change scenarios, as his group has asked, is critical to helping protect the broader Colorado River and stopping destructive dam projects.

Whether the questions the case raises about permitting and environmental protections ultimately make their way to the U.S. Supreme Court isn’t clear yet.

But James Eklund, a water attorney and former director of the Colorado Water Conservation Board, the state’s lead agency on water planning and funding, said Denver Water has the expertise and financial muscle to take it there.

“They have really sharp people over there,” he said. “I would say they are not only willing, they would have the facts to present a case they believe would be successful.”

Colorado Sun reporter Michael Booth contributed to this story.