WSP09828

• File Number: 8276.852
• Description: Moapa Valley Subevaluation Unit - Colorado River Salinity Control Project
• State: NV
• Basin: Colorado Mainstem
• Date: 6/1/1980
• Title: USDA Salinity Control and Environmental Assessment
• Water Supply Pro - Doc Type: EIS

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1 (17,390 tons), and (3) reducing erosion by shaping and seeding channel banks
2 with protective measures at road crossings (270 tons) and irrigation manage-
3 ment with return flow structures (5 tons). Installation of the erosion
4 control measures is estimated to reduce the annual sediment yield by 5,000
5 tons. These components are explained in Alternative 2, the recommended plan.
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7 Implementation of the recommended plan, Alternative 2 would require
semi automated onfarm irrigation systems with a total installation cost of

$3,040,900 or $263,900 annual cost. The annual operation and maintenance

cost would increase from $5,000 to $22,000 because of operation and additional
maintenance (and replacement) cost needed by the automated systems. These
increased costs would be offset by increased efficiency of crop production.

The exi sti ng canal and 1 atera 1 systems in Upper Moapa Va 11 ey need,

improvement. The improvement of distribution systems in Upper Moapa Valley

is needed to obtain onfarm improvements. A pipeline distribution system

in Lower Moapa Valley is recommended for the automated onfarm irrigation

systems. Total installation cost of the off-farm distribution system is

estimated to be $4,671,400 or $405,400 annual costs. Presently, about $12,000

is spent annually for operation and maintenance. This cost does not include

replacement commensurate with needs of the existing distribution system.

Operation, maintenance and replacement cost of the recommended off-farm
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distribution system would be $30,300 annually.

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