From The Denver Post (Scott Willoughby):

“We do a lot of guiding on the Fraser and Colorado rivers, and even before this we’ve lost a lot of insects. The green drakes on the Fraser are completely gone, a whole insect class that’s just disappeared,” said Ehlert, owner of Winter Park Fly Fisher and a 20-year guide with Grand County Fishing Company. “The other one was the salmonfly hatch on the Colorado. We still have them below Kremmling. But we used to get them on the river above Kremmling and now they are completely gone.” Ehlert believes he knows the culprit behind the mystery, and he’s not alone in pointing his finger squarely at trans-mountain water diversions he believes are sucking the life out of the Fraser River and Colorado headwaters. Shallow rivers and rising water temperatures have pushed the ecosystem to the brink, he said. “We’re fighting right now just to keep the water we have in the river, but I personally think we’re not being aggressive enough. We need to get the water back that’s gone,” he said. “If we lose any more, I think the whole system is going to crash. It may be too late now. Once the insects and food are gone, the fish are going to follow.”

Concerns over the health of the entire Upper Colorado River drainage have been magnified in recent months by proposals from Denver Water and Northern Colorado Water Conservancy District to annually draw an additional 45,000 acre feet from the Fraser, Williams Fork and Blue rivers through the Moffat Collection System Project and Windy Gap Firming Project. If approved, the water that would otherwise make its way into the Upper Colorado will instead be diverted across the Divide primarily for residential use among multiple municipalities along the Front Range from Greeley to Denver.

As part of the proposal, the water districts are expected to submit both a Fish and Wildlife Mitigation Plan and an Enhancement Plan to the Colorado Wildlife Commission at the April 7 workshop in Meeker. While the required FWMP addresses expected future impacts from the two projects, the optional enhancement plans are designed to address past and ongoing impacts to the river suffering the combined effects of development, agriculture, sediment loading, whirling disease and diversions, among others. The formal presentation of the plan starts a 60-day clock in which the Wildlife Commission will determine its official recommendation for or against the projects to the state.

More Colorado River basin coverage here.