WSP11214

• File Number: 8200.776
• Description: Uncompahgre River General
• State: CO
• Basin: Gunnison
• Water Division: 4
• Date: 1/1/1983
• Author: West Slope Hydro Par
• Title: Before the United States of America Federal Energy Regulatory Commission - Application for License for Major Project - Uncompahgre Valley Hydroelectric Project Number 2
• Water Supply Pro - Doc Type: Report/Study

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ooo's:Si

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with the Gunnison River at Delta.

West of the Uncompahgre

RivEtr a series of nearly level stream terraces separated by

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small valleys 50 to 100 feet deep have been carved by Uncom-

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pahgre

River

tributaries

as they traverse the area in a

northeasterly

direction.

These terraces or mesas are pre-

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dominantly stream deposits of varying ages and are remnants

of a once large outwash plain.

Three distinct terrace levels

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are

evident including the present flood plain or lower

ter-

races

about 5 to 10 feet above the river.

The higher

ter-

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races

are,

for the most part,

west of and about 300

feet

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above

the river while the middle terraces are only about

50

feet above the stream.

The area east of the river is undula-

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ting to rolling and is formed by the irregular erosion sur-
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face of the underlying Mancos Formation.

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The

surface formations

in the San Juan Mountains and

Uncompahgre Valley are composed of both igneous and sedimen-

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tary rock,

with the igneous material predominating in the

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mountains and the sedimentary in the valley.

In the Uncom-

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pahgre Valley there are significant volumes of gravelly
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material which were deposited by glacial melt-waters.

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