WSP00031

• File Number: 8200.776
• Description: Uncompahgre River General
• State: CO
• Basin: Gunnison
• Water Division: 4
• Date: 1/1/1972
• Author: DOI-BLM
• Title: Uncompahgre Project Colorado - Special Report on Need for Improvement and Extension
• Water Supply Pro - Doc Type: Report/Study

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CHAPTER II

RESOURCES AND USES

General Description

Many interesting and diverse topographic features surround the
project irrigated area. To the southwest, the irrigated valley lands
are joined by the long gentle slopes of the Uncompahgre Plateau that
are broken occasionally by deep canyons eroded by tributaries of the
Gunnison and Uncompahgre Rivers. The plateau reaches elevations of
over 9,000 feet and is a large geologic uplift that separates the
drainage basins of the Gunnison and Dolores Rivers.

The headwaters of the Uncompahgre River drain from the precipi-
tous slopes of the scenic San Juan Mountains that reach elevations of
over 14,000 feet. At the base of the mountains, the river is joined
by Dallas Creek and other tributaries in a system of valleys. The
river then enters a canyon about 10 miles long from which it emerges
near the southern end of the project land area.

The Black Canyon uplift rises along the northeastern side of the
Uncompahgre Valley and is named for the deep spectacular canyon eroded
by the Gunnison River into the crest of this large anticline. Much
of the canyon area is included within the boundaries of the Black
Canyon of the Gunnison National Monument. The area between the crest
of the anticline and the project irrigated area, includes a band of
badlands topography that has resulted from natural erosion of the
exposed Mancos shale formation. From many parts of the project area,
the rugged West Elk Mountains are visible beyond the Black Canyon
uplift.

Grand Mesa, a large flat-topped mountain rising to an elevation
of over 10,000 feet, dominates the horizon north of the project lands
and forms a part of the drainage divide between the Gunnison and
Colorado Rivers. Sedimentary formations of the basal portion of
Grand Mesa are capped by volcanic rock and glacial activity has created
numerous small lakes nesr the top of the mesa.

The region has a dry continental climate with warm summers and
moderately cold winters. During warm summer periods temperatures of
the lower valleys, occasionally exceed 1000 F. but usually drop to
o
60-70 F. range during the early morning hours. For short periods
during the winter, the minimum temperatures drop below 00 F. but
usually rise to the 20_jOO F. range in the afternoons.

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