WSP00691

• File Number: 8142.700
• Description: Trinidad Project - Annual Operating Plans and Reports
• State: CO
• Basin: Arkansas
• Water Division: 2
• Date: 12/1/1996
• Author: US DoI BoR
• Title: Review of Operating Principles and Project Operations Final Report
• Water Supply Pro - Doc Type: Operating Principles/Plan

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allowance has been made for individual ditch transportation losses. provided, the allocation

shall not exceed the irrigation requirement at the farm headgate. The District water supply

allocations must be strictly administered and enforced to attain optimum beneficial use of the

District water supply. Article IV.B.3.(c) provides that after the irrigation capacity is empty, as

determined by the District, the District will relinquish exercise of the direct flow water rights;

provided, that if reservoir inflow plus divertable stream gains below Trinidad Dam exceed the

irrigation requirement. and the excess flows are storable the District will resume the exercise of

the direct flow rights and exercise the District's storage rights.

As indicated in the paragraph above, determination of a canal and lateral transportation

loss allowance for the individual ditch systems and the irrigation requirements are important

elements in operation of the Project for optimum beneficial use of the District water supply. The

District has not determined transportation losses for the individual ditch systems, but has assumed

the equivalent value for all the Project ditch systems that was determined and used in the project

planning studies; thus using the same value of 30 percent for all the ditch systems. The District

should either use the theoretical values (Appendix E) for the individual ditch systems used in the

planning studies or determine values with field measurements. The use of the equivalent

transportation loss value effectively allocates the District water supply prorata on acres contracted

and does not result in an equitable share of the District water supply at the farm headgate

considering individual ditch losses.

The District has not developed a methodology for determining a current real time

irrigation requirement. The irrigation requirement limits the water supply allocation, determines

when the irrigation season is opened and closed and when the District resumes exercise of the

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