PROJ00116

• Contract/PO #: C153477
• Contractor Name: Victor, City of
• Water District: 0
• County: Teller
• Bill Number: XB 99-999
• Loan Projects - Doc Type: Feasibility Study

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Alternatives Description

According to the hydrologic analysis completed for this report, the existing
spillway has the capacity to pass the 100-year storm event with approximately 1.8
feet of freeboard. However, the Probable Maximum Flood (PMF) would overtop the
dam crest by approximately 3.8 feet and 1/2 of the Probable Maximum Flood would
overtop the dam by approximately 2.7 feet. The existing emergency spillway will
pass only about 20% of the Probable Maximum Flood without overtopping the dam.

Under the State Engineer's current rules and regulations for dam safety and
construction, any proposed modifications to improve the emergency spillway should
be designed to accommodate the full PMF. However, the State Engineer is currently
considering several hydrologic criteria for inclusion in the rules and regulations
for dam safety and construction. Under these new hydrologic criteria the Victor
No.2 dam would be classified as a Class III dam, allowing spillway improvements
to be designed for one-half of the PMF. It is expected that the new criteria
will be adopted in late December 1986 or early January 1987. Therefore, four
improvement alternatives were evaluated for rehabil itation of the Victor No. 2
Dam which include both the PMF and 1/2 of the PMF. A brief description of the
alternatives follows:

Alternative #1 - Alternative #1 examines the feasibility of enlarging the existing
emergency spillway in order to safely pass the full PMF. Figure 5.3 presents a
sketch of this alternative. The spillway crest will be raised 1.5 feet to its
previous elevation of 10,392 feet. This elevation is at a reservoir capacity of
210 acre-feet which is approximately the amount allocated for water storage
according to the water rights owned by the City of Victor. The proposed spillway
will have a 350 foot bottom width and 2H:1V sideslopes. The top width of the
spillway will be 378 feet. Riprap protection will be placed along the emergency
spillway sideslope adjacent to the dam embankment to protect against erosion of
that slope. The south sideslope of the emergency spillway is cut into natural
ground and will not require riprap protection. A concrete grade beam 2-feet wide
and 6-feet in depth will be required along the emergency spillway crest to
maintain the crest elevation and to prevent erosion of the spillway during
operation. The beam will be buried and will have a trapezoidal configuration

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