WSP08880

• File Number: 8277.500.10
• Description: Price and San Rafael Basin Unit - Colorado River Water Quality Improvement Program
• State: UT
• Basin: Colorado Mainstem
• Date: 3/1/1986
• Title: Evaluation of the Incremental Cost Effectiveness of Building a Combined Pressurized Sprinkler Irrigation System to Reduce Salt Loading to the Colorado River
• Water Supply Pro - Doc Type: Report/Study

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Soil Conservation Service Estimates

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~.:3~er and salt budgets developed by the SCS for present conditions are pre-

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sented 1n Figure II-2.

Based on an inflow to the ground water system of

57,821 acre-feet from irrigation deep percolation and canal loss, and a salt

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pickup i, the ground water system of t~e irrigation sector of 149,175 tons per

year, a sal t load ing factor was developed.

This factor indicates that based

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on SCS data that for each acre-foot of water that can be prevented from

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entering the ground water system in the agricultural area, 2.6 tons of salt

per year will be prevented from entering the Colorado River.

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This analysis was completed to compare budget estimates by the SCS and

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Reclamation.

This comparison was based

on the deep percolation into the

ground water

system.

The salt loading

factor of 2.4 tons/acre-foot by

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Reclamation agrees closely with the salt loading factor of 2.6 tons/acre-foot

developed by the SCS.

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The SCS has based their salt reduction on differences in return flow; however,

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the SCS water budgets provide sufficient data to determine the changes in deep

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percol at ion for various on- farm improvement opt ions.

For both on- farm and

off-farm systems a loading factor of 2.4 tons/acre-foot was used to determine

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salt reduction.

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