Board Meeting 10/07/1982

• Board Meeting Date: 10/7/1982
• Description: CWCB Meeting
• Board Meetings - Doc Type: Meeting

It was originally anticipated that an economic evaluation of
the proposed project would be accomplished. !lowever, during the
data-gathering phase of the study, it was found that material
from an early 1960's geotechnical investigation of the Hardin Dam
site was no longer available. Since this information is crucial
for embankment design, it was decided to undertake qeotechnical
field investigations. In light of the fact that s.a. 439 limits
the expenditures which can be made on a study, the economic
analyses had to be deleted in favor of the geotechnical work.

To date, water yields analyses as well as most of the
technical work associated with dam and spillway design, reservoir
design, reservoir operations, and cost estimates have been
completed. preliminary unit cost estimates per acre-foot of
storage capacity have also been developed.

It has been found that COnservation storage at the Hardin
site could range from about 200,000 to 600,000 acre-feet
(conservation storage is that portion of total reservoir capacity
which would store water for agricultural and municipal uses). It
was decicjed to proceed with reconnaissance-level de~igns for a
project with 400,000 acre-feet of conservation storage, both with
and without 200,000 acre-feet of storage for flood control. In
addition to the specific design and cost estimate for a reservoir
with 400,000 acre-feet of conservation storage, the study will
include information which will enable one to estimate the cost
and yield of any sized reservoir between 200,000 and 600,000
acre-feet of conservation storage.

Una Dam proiect

This proiect would consist of an earthfilled dam, concrete
spillway, and associated hydropower facilities located on the
mainstem of the Colorado River upstream of DeBeque, with a
reservoir extending upstream ~o the Town of Parachute. The
Objective of this study is to evaluate, at a reconnaissance level
of detail, the engineering feilsibility and cost of the proposed
project. The primary purpose of this project would be to develop
water fOr industrial use, with some municipal uses also being
possible.

The majority of the wor~ completed to date has centered
around water rights and reservoir yield analyses, geotechnical
fiel" investigations, and project layout and design. It is
estimated that the reservoir '-'iill orovide a firm annual vie:;'d of
about 175,000 acre-feet under a sc;nario that assumes th~
transfer of the Placita Reservoir conditional storage decree from
the Crystal River to the Una site and the "most likely" level of
development of conditional decrees which are senior to the
Placita decree. The project layout is near completion, with a
dam nearly 150 feet high, a 3~ megawatt hydroelectric power plant
and a reservoir capacity of 196,000 acre-feet.

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