PROJC01820 ‎(2)‎

• Contract/PO #: C150189
• Contractor Name: Larimer and Weld Irrigation Company, The
• Contract Type: Loan
• Water District: 2
• County: Weld
• Loan Projects - Doc Type: Feasibility Study

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partially demolished and new retaining walls constructed as the existing walls have tilted in so
much they have essentially failed. The check structure at the Big Windsor Inlet would have to
have the right wingwall stabilized and the stoplog supports would have to be demolished and
replaced. The Finley Check would require stabilization of the wing walls and would require the
addition of a gate and supports orstoplog guides to make it a viable check.

In addition to the repairs, the ditch company has a need to be able to measure the flow downstream
of the Lake Lee Dam and also measure the inflow into Big Windsor Reservoir. So, in addition
to the repair, a Parshall measuring flume is needed at each location and will be included in the cost
of this option.

The estimated construction cost to repair the structures and add a Parshall flume at the Lake Lee
Dam and Big Windsor Inlet is estimated to be $ 471,100 as shown in Table 2. This cost is
approximately 35 % of the cost to replace all the structures with new concrete structures.

This alternative, although less expensive initially than the replacement alternative, has several
disadvantages when compared to the third alternative. The structures will be patched and
repaired, but will have a shorter life span than a new structure. We would estimate the structures
would most likely be ready for complete replacement in approximately 25 to 30 years. The new
structures would be expected to last on the order of 100 years with repair on the gates and controls
required every 25 years. The repaired check structures would utilize the same method of
checking the ditch by using stoplogs which is difficult and dangerous on this size of ditch. No
improvements in operational efficiency can be achieved with the repaired alternative using stoplogs
for the checks. The addition of gates to the old check structures is not feasible due to the
condition of the structure walls and the lack of reinforcing steel in the walls and slab.

Larimer & Weld Feasibility Study
Lake Lee & Big Windsor - 03.043

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