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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Climate

Mos~of the Uncompabgre Valley is semiarid, but rainfall and

temperature vary widely with elevation. Tbe prevailing wind

is from tbe west, but a wide range of surface wind condi-

tions exists as influenced by specific topographic features.

Average annual precipitation ranges from 8 inches at Delta

and 13 inches in tbe upper valley south of Montrose to as

much as 110 inches in tbe mountains. The frost-free period

averages about 127 days annually and varies from 112 days in

the upper valley to 1118 days in the lower valley area.1

Water Quality ~ Salinitv
As a part of the Colorado River Water Quality Improvement

Program (CRWQIP) 1, the U.S. Department of tbe Interior

Bureau of Reclamation prepared a feasibility report and

draft environmental impact statement to determine a feasible

plan for improving the water quality in the Lower Gunnison

Basin Unit which includes the Uncompahgre River Valley. The

intent of the Lower Gunnison Basin Unit investigations, com-

pleted in December 1982, was to determine a feasible plan

for improving tbe quality of water in tbe Uncompabgre River,

a tributary of tbe Gunnison River which in turn flows into

the Colorado River. Tbe large amount of salt pickup is

attributable to conveyance system seepage and deep percola-

tion as the water passes through the weathered and fractured

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