C150094 Application ‎(2)‎

• Contract/PO #: C150094
• Contractor Name: La Plata Water Conservancy District
• Contract Type: Grant
• County: La Plata
• Loan Projects - Doc Type: Application

evaluate funding sources such as construction loan from the CWCB; a
construction grant from the Colorado Water Resources and Power
Development Authority authorized on November 30, 2001,which included
$15 Million for grants and loans to fund projects to improve irrigation and
domestic water management on the La Plata River; funding to support a
wildlife/instream flow; funds from irrigators; and other water user
payments.
Formulation of Alternatives
A. WWE will formulate and evaluate alternatives to increase the height of the
dam based upon the available data. Results will be presented for:
1. Available borrow material, in situ properties and suitability for use as
compacted fill material in zones of the embankment.
2. The suitability of material in proposed borrow areas for compared
embankment, riprap and concrete aggregate.
3. Preliminary embankment section including zones compatible with the
available fill material(s).
4. Methods to reduce seepage at the abutments and beneath the foundation
of the dam.
5. Slope protection.
6. Alternate emergency spillway and outlet alignments and configurations
based upon cost, safety and subsurface conditions.
7. Other geotechnical and geologic considerations for design and
construction.
Hydraulics &Hydroelectric
Hydraulics issues related to the dam construction will be evaluated. These issues will
include inlet conditions, sizing of outlet works, spillway needs, and conditions in the
receiving channel. In addition,the condition of the existing outlet works will be
evaluated. Consideration of these issues is intended to identify potential hydraulics
related fatal flaws for the site and will be incorporated into the alternatives analysis.
In the case of the spillway, the design storm used in the evaluation will be based upon a
classification that is related to the size of reservoir, the height of the dam and the
potential for property damage or loss of life downstream in the event of a failure. The
outlet structure must be sized to draw the reservoir down quickly during an emergency.
Both the spillway and the outlet works must be sized for anticipated flows and provided
with suitable energy dissipation structures at the downgradient outlet.
The feasibility study will also include limited evaluation of the potential for the enlarged
reservoir to be used for hydroelectric generation. The evaluation will focus on financial
feasibility but will also consider feasibility of construction.
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