WSP11446

• File Number: 8220.112.I
• Description: Dallas Creek Participating Project
• State: CO
• Basin: Gunnison
• Water Division: 4
• Date: 10/1/1979
• Author: USDOI-BOR
• Title: Endangered Species Assessment: Dallas Creek Project Colorado
• Water Supply Pro - Doc Type: Report/Study

The majority of this entitlement is already in use and the present

flow regime of the Colorado River system differs significantly from that

of one hundred years ago.

More specifically the flow regime in the Gunnison River and the

Colorado River has been greatly altered by transmountain diversion, private

and public irrigation projects, storage reservoirs, and hydroelectric

developments. On the Gunnison River drainage irrigation began before 1900.

The Gunnison Tunnel began diverting approximately 1,000 cfs from the

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Gunnison River for irrigation in 1910. Taylor Park Reservoir, the first

major storage reservoir in the drainage, was operational in 1938; and Blue

Mesa Reservoir, the largest of the three Curecanti Reservoirs, was operation-

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al by 1966. Table 5 illustrates some of these changes, particularly the

effect of the Curecanti Unit in reducing springflows and increasing other

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flows.

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In the Colorado River drainage upstream from the Colorado-Gunnison

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River confluence,over 200,000 acres of irrigated land has been developed;

storage reservoirs have capacities over 750,000 acre-feet, and transmountain

diversions remove over 300,000 acre-feet from the basin.

Water of the State of Colorado that remains uncommitted within its entitle-

ment as provided in the 1948 compact is over appropriated many times by

conditional decrees and recent claims. Potential depletions of the Colorado

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River system by the Dallas Creek Project are considered to be within the

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state's entitlement. The use of the remaining entitlement represents the

cumulative impact of water development in Colorado by all water users.

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