Drought, Schmought: Shoshone Protocol Spells Higher-than-Average Flows in Upper Colorado

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Believe it or not, in this year of historically low runoff in Colorado, the state’s main artery, the Colorado River, is running higher than average in Class V Gore Canyon and Class II Lower Gore Canyon downstream (1,150 cfs), and perfect for rafters in Shoshone Canyon near Glenwood Springs. And paddlers owe it all to something called the Shoshone Outage Protocol…

Initiated in June, the release came as an agreement worked out between the Colorado River District, Denver Water and the Bureau of Reclamation, who cooperated to add flows for the benefit of fish, rafting and crop irrigation along the entire stretch of the mainstem from Parshall in Grand County to Grand Junction in Mesa County.

The extra water is the result of the Shoshone Outage Protocol, a part of the Colorado River Cooperative Agreement that was hammered out over the last six years by 42 West Slope entities and Denver Water.
The three reservoir operators are increasing river flows by about 450 cubic feet a second (cfs) through releases from Wolford Mountain Reservoir, Williams Fork Reservoir and Green Mountain Reservoir, respectively.

Flows in Glenwood Canyon should hover around 1,100 cfs, to improve rafting and to aid farmers and ranchers in the Grand Valley, helping to boost flows that are too low. The 71‐year average of flows for this time of the year in Glenwood Canyon is more than 6,000 cfs.
Additionally, the flows are helping to lower water temperature levels in the river along the Pumphouse area of the river in Grand County to help trout survive.

“This makes a real difference in the river,” said Colorado River District General Manager Eric Kuhn. “Since we started, you can see by the gage that the temperature of the water has come down 4 degrees Fahrenheit.”

The Protocol is designed to add water to the Colorado River when the Shoshone Hydro Plant in Glenwood Canyon is down for maintenance and not using its senior water right, which normally would have the river flowing at about 1,250 cfs through the canyon, absent the usual runoff flows. The Protocol is taking place even though all the parties have yet to sign the agreement.
“This is a good example of how the Colorado River Cooperative Agreement can work when everybody is pitching in to help the river in a time of need,” said Lurline Underbrink Curran, the Grand County Manager.

Said Jim Lochhead, CEO/Manager of Denver Water, “This is exactly why we all came together to sign the Colorado River Cooperative Agreement – to provide benefit to the Colorado River. Denver Water is proud to be part of an effort that fulfills our goal to operate our system in a way that benefits the environment.”

Currently, the Shoshone Hydro Plant is operating at about half capacity, which requires about 700 cfs of water. Xcel Energy is unable to run Shoshone at full capacity while it works on repairs to the tunnel that runs about two miles from the Hanging Lakes power plant dam to the power plant itself. The work could last until early September.

A call on the river, such as the Shoshone 1,250 cfs water right, forces junior water rights holders to replace diverted water from reservoir storage or to stop diverting, thus boosting flows as they decline with the natural drop of the runoff throughout the summer.

And, as it turned out, it didn’t have to last long. “The protocol operated for less than a week before a Grand Junction area irrigation water right came active on the river and accomplished the same result under the water rights system,” says CRD’s Jim Pokrandt.