WSP00377

• File Number: 8220.128.A
• Description: Silt Project
• State: CO
• Basin: Colorado Mainstem
• Water Division: 5
• Date: 10/1/1945
• Author: USDOI - BOR
• Title: Silt Project-Colorado ‎(Draft of Project Planning Report)‎ Part 2 of 2
• Water Supply Pro - Doc Type: Report/Study

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C\J to exceed 27% of the water available at the end of the canal or at the

reservoir, making a requirement at such points of 3.00 acre-feet per

acre. Losses between the point of diversion on East Rifle Creek and

releases from the reservoir including reservoir losses have been estimated

at approximately 10% of the diversion at the head of the canal. Thus

the total diversion requirement for Grass Valley land is estimated to be

3.40 ac~e-feet per acre. Davie Ditch land has been estimated to require

a similar diversion from the Rifle Gap Reservoir.

A diversion requirement of 3.40 acre-feet compares very favorably

with the requirement on other lands with similar soil a.nd climate. It

is less than that now used on the lands irrigated by the lower ditches

of Rifle Creek which hold the prior water rights of the creek., The

lower Rifle Creek land. on the average, has higher transmission and

distribution losses than project lands and there is always a tendency

on the part of prior right water users to divert more water from a

stream than is actually required for full irrigation. A:n est,imate of

replacement water required for the prior right land of lower Rifle Creek

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a figure of 4.5 acre-feet per acre has been used to insure ample coverage.

The monthly pattern of water use will be somewhat governed by the

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crop program of the land irrigated. For crops anticipated as discussed

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in Appendix C, the following quantities are estimated as ideal demand

requirements for the Grass Valley Canal land, the Davie Ditcp land, and

the lower Rifle Creek land:

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