On July 6, the U.S. Army Corps of Engineers approved a project by Denver Water to raise the dam at Gross Reservoir by 131 feet.
If it gets built, the dam at Gross Reservoir would be tallest in the state. It would constitute the biggest construction project in Boulder County history. Denver Water says the expansion would increase the reservoir’s capacity by about 25 billion gallons, or about six times the size of Boulder Reservoir. They say the dam needs to be expanded in order to meet the needs of the one million new people they project will be in their metro Denver service area by 2040.
But opponents say if the dam is expanded, it will effectively kill the Colorado and Fraser rivers, and other smaller waterways, by diverting up to 80 percent of the water in the Upper Colorado River basin.
The area in question is in and around the Fraser Valley and the water would be pumped through the mountains into Gross Reservoir in Boulder County by way of a tunnel.
Critics of the plan point to studies that indicate global warming will sap the entire Colorado River of up to 30 percent of its water by mid-century, making it impossible to divert the planned amount of water. And, they say, Denver Water doesn’t need more supply: the company has reduced consumption by 22 percent since 2002 despite a 10 percent increase in population, according to its own data.
Denver Water says it has a plan to mitigate the environmental effects of the project. Opponents don’t believe it and the two sides disagree on population and environmental impact studies used to justify the expansion. They even disagree on whether or not Denver Water needs to receive a permit from Boulder County to expand the dam.
So, who’s right? And what obstacles remain in Denver Water’s way before shovels hit the ground at Gross Reservoir?
Read more here.