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• Board Meeting Date: 7/19/2009
• Description: CF Section - New Project Loans - Farmer's Reservoir and Irrigation Company - Milton Reservoir and Barr Lake Improvements Project
• Board Meetings - Doc Type: Memo

Farmers Reservoir and Irrigation Company Agenda Item 10
July 14, 2009
Page 5 of 8
TABLE 1
PROJECT COST - MILTON RESERVOIR OUTLET WORKS
Construction $ 59 1 , 0 00
Testing $ 11, 0 00
Contingency $ 5 6, 0 00
Constr uction Management $ 40 , 0 00
TOTAL $ 69 8,0 00
B. Milton Reservoir Spillway
The SEO has indicated that the existing spillway at Milton Lake is not adequate to safely
pass the design storm event and has directed the Company to design and construct a
large r spillway to meet State standards.

Alternative No. 1 No Action:
– This alternative was considered unacceptable because by
not increasing the capacity of the spillway, the Company would be ignoring the
requirements of the SEO and Milton Reservoir would li kely be put under a fill restriction.
Alternative No. 2 (SELECTED) – Enlarge the Spillway with a Concrete Control
Structure and Earthen Channels Upstream and Downstream from the Spillway Crest :

This alternative involves enlarging the existing spillway. This alternative would meet the
Company ’s objective of improving the spillway to safely pass the design storm event as
dictated by the SEO ; thereby allow ing the Company to continue to operate Milton
Reservoir to its full decreed amount without the concern of the dam overtopping. The
estimated cost for this alternative was $98 4,0 00.
Alternative No. 3 – Enlarge the Spillway with a Concrete Control Structure and
Concrete Channels Upstream and Downstream from the Spillway Crest:
This
alternative involved modi fying the existing spillway by expanding it just as in Alternative
No. 2. In addition, 400 feet of channel downstream of the spillway crest would be
armored with a concrete lining to prevent erosion downstream from the spillway crest
section. This would e liminate spillway maintenance if an event was to occur. The
estimated cost of this alternative was nearly $3,900,000.
The Company selected Alternative No. 2 because it meets its objectives of continued safe
operations of the dam, it complies with the SEO ’s directive that the spillway be enlarged ,
and it will allow the Company to continue to store its maximum decreed water volume,
all in a cost effective manner.
This portion of the Project involves widening the spillway from 350 feet to 586 feet and
lower ing the elevation of the spillway by 1.5 feet. Areas upstream and downstream of the
spillway will be graded to provide an efficient flow path from the reservoir through the
spillway and on downstream of the dam. Appropriate hydraulic cutoff walls w ill be a dded
downstream from the spillway to prevent erosion during the design storm event.