C153773 Feasibility Study

• Contract/PO #: C153773
• Contractor Name: Morrison, Town of
• Contract Type: Loan
• Water District: 9
• County: Jefferson
• Bill Number: HB 95-1155
• Loan Projects - Doc Type: Feasibility Study

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Operating Reservoir. The treatment plant would continue to take water from the intake at a
controllable rate adjusted by a valve, or water could flow backward from the operating reservoir
to the treatment plant.

Connecting the existing 12-inch cast iron pipe gravity intake line directly to a new 14-inch ductile
iron pipe would fill the Morrison Operating Reservoir at a flow rate of 2.5 cfs without pumping.
The new pipeline would connect directly to the existing 8-inch (to be increased later) outlet
pipeline at the reservoir. These capacity calculations assume improvements to the upper intake
pipeline at the headgate to increase the pressure head. If this capacity to the reservoir becomes
inadequate near full build-out, a simple booster pump installed in the future at the treatment plant
would increase the flow rate. Note that this transmission line would be 14-inch size if the
existing water treatment plant site is used (Options C-1 or C-3) and 16-inch size with a new
higher plant (Option C-2).

The project cost for the 2,000 lineal feet of new 14-inch ductile iron pipe is expected to be
approximately $100,000. The same pipeline alignment could be used so no new easements
would be required. This project should be completed prior to filling the Cooley Reservoir to
provide greater water supply capacity. The operational reservoir should be completely filled prior
to construction and the treatment plant will operate directly on intake diversions during the
construction period.

Pumping from the Operating Reservoir to Cooley Reservoir
Water will be pumped from the Morrison Operating Reservoir to the Cooley Reservoir as needed,
or at a rate to match supply with demand so that the Morrison Operating Reservoir is not
drained. With the improvements to the intake pipe, and the reach between the plant and the
operating reservoir, the supply will be in excess of the peak 2.5 cfs pumping rate to Cooley
Reservoir. Level sensors in both reservoirs will be used to control the operation of the pumps.

The Morrison Operating Reservoir is at elevation 5955 feet, approximately 502 feet in elevation
lower than the Cooley Reservoir. The total pump power requirement is assumed to be 224
horsepower. Two pumps would likely be used, each with 112 horsepower. The daily cost of
pumping at 2.5 cfs would be $280, or $56.50 per acre-foot, and the total cost to fill 500 acre-feet
in the Cooley Reservoir would be $28,250.

The pipeline alignment from the operating reservoir to Cooley Reservoir should follow the
shortest route to: (1) use less pipe, (2) minimize friction losses in the pipe, (3) avoid utilities to
the extent possible during construction, (4) minimize disturbance to roadways, and (5) eliminate

70.0aO.035:MSTR-PLN

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