Denver Water can finish its Gross Dam expansion and fill the controversial reservoir in western Boulder County, the 10th U.S. Circuit Court of Appeals ruled Tuesday, lifting an injunction by a lower court judge and confirming the dam’s permits as sound.
The appeals court said the U.S. Army Corps of Engineers had acted responsibly in issuing construction permits for the $600 million expansion, which is largely complete and will be filled using water rights Denver holds in the Colorado River basin on the western side of the Continental Divide.
A federal district judge in Denver had issued the injunction after declaring the Corps had failed to consider less-damaging alternatives, or the fact that climate change could dramatically reduce the amount of Colorado River water available to fill the storage pool. But the appeals court rejected that view.
“We do not think the Corps’s choice of cost methodology was arbitrary or capricious,” the appeals court ruling said. The plaintiffs, including nonprofit Save the Colorado, argued the Corps rejected clear evidence of climate change, but the appeals court ruled the Corps gave the research fair consideration.
“The Corps considered — and rejected — the reliability of that and similar studies, one of which showed that in the Colorado River Basin, ‘no consistent trends in annual precipitation have been detected over the last 100 years,’” the appeals court said.
“In the end, the environmental groups ask us to substitute our judgment for the Corps’s. They point out scientific studies that, in their view, rebut the Corps’s reading of the scientific literature and ask us to opine on what the scientific research establishes,” the appellate ruling said. “But our job is not to second-guess the Corps’s assessment as long as it rests on a reasoned basis.”
Denver Water said it looked forward to completing a crucial water supply project it began permitting 23 years ago.
“We’re pleased to see the 10th Circuit Court of Appeals confirm that the Gross Reservoir Expansion Project was lawfully permitted by the U.S. Army Corps of Engineers and that Denver Water can proceed with the final stages of this critical project to ensure a safe, secure water supply for the 1.5 million people we serve,” according to a statement from spokesperson Todd Hartman. “With this decision, Denver Water can move forward with completion of construction, site preparation and eventual filling of the expanded reservoir. An expanded Gross Reservoir is vital to the future of the Denver region.”
“It’s nonsensical to be putting more straws in, and further draining, the Colorado River at this point in history,” Wockner said. “That the law allows it to happen doesn’t make it right, it just makes it legal. I saw something wrong, I stood up, spoke out and took action. It was the right thing to do and I would do it all over again.”
Wockner said Tuesday the plaintiffs would not be appealing the decision to the U.S. Supreme Court.
Gross Reservoir Dam backs up South Boulder Creek, while also taking in water through the Moffat Tunnel under the divide, from the Fraser and Williams Fork rivers in the Colorado River basin. Denver Water has said the expansion is needed to balance its water storage system currently heavily concentrated on the southern end of the metro area.

Print