Reservoir agreement helps trout by borrowing endangered fish water — The Grand Junction Daily Sentinel

From The Grand Junction Daily Sentinel (Dennis Webb):

Some rejiggering of reservoir operations in the upper Colorado River watershed is taking the heat off trout in Grand County through the early release of water that had been set aside for endangered fish in Mesa County.

The approach is being made possible by storing water elsewhere so it can be released for the endangered fish when they need it later.

Under the agreement involving the U.S. Fish and Wildlife Service, the U.S. Bureau of Reclamation and Colorado River District, an additional 35 cubic feet per second of water started being released last week from Lake Granby, also known as Granby Reservoir, in the Colorado River headwaters. That nearly doubled Colorado River flows immediately downstream.

The increased flows help reduce daytime temperatures in the river, which had begun topping 60 degrees and threatening the health of trout. The releases involve water normally stored in Granby for use in boosting flows in the river near Grand Junction for endangered fish such as the humpback chub and razorback sucker.

The endangered fish still will get water under the deal, however. In exchange for the additional water coming out of Granby, the river district is withholding 35 cfs of water from Wolford Mountain Reservoir, which sits above Kremmling on Muddy Creek, a Colorado River tributary. That’s below the problem stretch of the Colorado River, thanks to inflows to the river coming from Muddy Creek and other tributaries, so the Wolford water that’s being withheld doesn’t hold the importance to the trout that the released Granby water does.

“There’s plenty of water in the river except for in that stretch below Granby,” said Jim Pokrandt, a river district spokesman.

Pokrandt said the Colorado River is currently a “free river” right now in Colorado. There are no calls on it to meet the needs of senior water rights holders when flows are more limited. But the upper stretch in Grand County in the Hot Sulphur Springs area is depleted due to transmountain diversions to the Front Range.

Withholding the Wolford water means it will be available for the endangered fish during lower-flow periods on the Colorado River in Mesa County, in lieu of the water that is being released from Granby.

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