WSP06922

• File Number: 8027
• Description: Section D General Correspondence - Federal Agencies - US DOI-BOR - Region 4
• State: CO
• Basin: Statewide
• Date: 11/1/1971
• Author: DOI-BOR
• Title: Final Environmental Statement - Crystal Dam Reservoir and Powerplant - Curecanti Unit - Colorado River Storage Project
• Water Supply Pro - Doc Type: Report/Study

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through the Gunnison Tunnel for irrigating Uncompahgre Project
lands. Therefore, one of the prime functions of Crystal Reser-
voir in the plan was to reregulate fluctuation of Morrow Point
releases to maintain a constant 24-hour flow of about l,OOO
second-feet through the Gunnison Tunnel and provide at least
200 second-feet in the river below the Gunnison Tunnel diver-
sion works for fish and wildlife without reducing power pro-
duction at the Morrow Point Powerplant.

Historically the Gunnison River has produced a great volume of
ice which contributed to bank erosion and flooding of inhabi-
ted areas near the river between its confluence with North
Fork and below the city of Delta, Colorado. Since construc-
tion of Blue Mesa and Morrow Point this reach of the river has
been ice free. Crystal releases will help insure this ice
free stretch through Delta.

B. General Description of Key Features in the Project

1. Existing features.--The Curecanti Unit is comprised of
three reservoirs located in the 40-mile reach of the Gunnison
River upstream from the boundary of the Black Canyon of the
Gunnison National Monument to the town of Gunnison, Colorado.
The Curecanti National Recreation Area has been established
to include the three Curecanti reservoirs and their appurtenant
recreational facilities. The Recreation Area is being admin-
istered by the National Park Service.

The two upper dams with powerplants have been constructed to
date and are in operation--Blue Mesa and Morrow Point. The
attached Project Map No. 622-400-l20 indicates the locations
of these features.

The Blue Mesa Dam is at the upstream end of the unit. The dam
is an earth and rockfill structure with a reservoir capacity
of about 940,800 acre-feet. The Blue Mesa Powerplant has an
installed capacity of 60,000 kw.

Blue Mesa is followed downstream by Morrow Point--a concrete-
arch dam with a reservoir capacity of 117,190 acre-feet and a
powerplant with an installed capacity of 120,000 kw.

Morrow Point is followed immediately downstream by the Crystal
Dam and Reservoir site. The dam will be constructed under a
two-stage construction program. The first stage will consist
of a diversion tunnel to bypass the river during construction.
The anticipated date of initiating tunnel construction is
January 1972, and the contract will run approximately 14 months.
The second stage will be contracts for the darn and powerplant.
It is anticipated that the prime contract for the dam and

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