9570

• UCREFRP Catalog Number: 9570
• Author: U.S. Department of the Interior.
• Title: Preliminary Analysis
• USFW Year: 2000.
• USFW - Doc Type: Wayne N. Aspinall Unit Operations and the Federal Water Right Claim, Black Canyon of the Gunnison National Park.
• Copyright Material: NO

The Colorado Water Court has awarded the United States a 1933 Federal reserved water right for
flow in the Gunnison River for the National Park (formerly National Monument). The
Department of Justice has requested that Interior agencies formulate a quantification of this right
that is supported Department-wide.
Aspinall Unit Facility Statistics
Blue Mesa Morrow Point Crystal
Capacities (af)
Dead 111,200 165 7,700
Inactive 81,070 74,905 4,650
Active 748,430 42,120 12,890
Live 829,500 117,025 17,540
Total 940,700 117,190 25,240
Elevation range (ft)
Dead 7186-7358 6747-6808 6547-6670
Inactive 7358-7393 6808-7100 6670-6700
Active 7393-7519.4 7100-7160 6700-6755
Total 7186-7519.4 6747-7160 6547-6755
Outlet capacity (cfs)t
Power plants (max.) 2,600-3,400 5,000 1,900
Bypass 4,000-5,100 1,500 1,900-2,100
Combined max. 6,000'- 6,500 4,000
Spillway 34,000 41,000 41,350
I Capacities vary with reservoir elevations.
- Shared penstock limits the combined maximum capacity of power plant and bypass outlets at Blue Mesa.
Hydrology
The Gunnison River originates where the East and Taylor Rivers join in Gunnison County. From
that point, the river flows 25 miles to Blue Mesa Reservoir and on through Morrow Point and
Crystal Reservoirs. From Crystal Reservoir, it flows approximately 2 miles to the Gunnison
Tunnel. From the Gunnison Tunnel, the river flows 29 miles to the North Fork confluence. It
then travels 75 miles to its confluence with the Colorado River at Grand Junction, Colorado.
About 40 percent of the annual flow of the Colorado River at the Colorado-Utah state line comes
from the Gunnison River.
The area of the watershed that flows into the Aspinall Unit is approximately 4,000 square miles.
At the U. S. Geological Survey gage (tunnel gage) in the National Park, historical average annual
flows have been 1,320 cfs for the period of record since 1911; daily flow extremes ranged from a
few days of no flows to 19,000 cfs, both before the Unit was constructed. These ranges have
been moderated under Unit operations. Another important measurement point on the river is the
Whitewater gage, 8 miles upstream from the Colorado River confluence. At this point the
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