18c

• Board Meeting Date: 3/18/2008
• Description: CF Section - New Project Loans - Supply Irrigating Ditch Company - Knouth Reservoir Dam Rehabilitation
• Board Meetings - Doc Type: Memo

Supply Irrigating Ditch Company - Knouth Reservoir
March 11, 2D08
Page 3 of 5
Project Description
Agenda Item 18c
The purpose of this project is to enhance the means for the Company to continue providing irrigation
water to shareholders by adding another storage option. This will be achieved through the
rehabilitation of the Reservoir to its original capacity. Three alternatives were considered:
1. The no-action alternative.
2. Rehabilitation of the entire dam and all appurtenant structures.
3. Rehabilitation of areas of dam that have seepage problems.
Alternative No. 1 No action was considered unacceptable because if the dam improvements are not
completed the SEO could require the breach of the dam. This would eliminate this Reservoir site as
a storage option; therefore not achieving the project goal.
Altef°native No. 2- Rehabilitating the entire dam was ruled out because the scale of the project and
associated costs were greater than necessary (when compared to Alt. 3) to achieve the goal of
restoring the reservoir to its original capacity. This option involved reshaping the upstream face of
the dam, removing the existing outlets, constructing a new box culvert inlet and improving a section
of the Supply Ditch.
Alternative No. 3 Rehabilitation of seepage areas of dam and improvements to supply ditch was
the selected alternative because it is the most cost effective way to repair the dam so the Company
can use the Reservoir for storage.
The selected alternative, Alternative No. 3, includes construction of a spillway, removing vegetation
from the embankment of the dam, lining select areas on the upstream dam face with a clay liner,
placing riprap along the upstream dam face, enclosing an irrigation ditch within a pipe, and installing
dam instrumentation.
URS has begun preparation of engineering design and cost estimates for the project. The design is
scheduled to be completed and submitted to the SEO for approval in May 2008. Pending SEO
approval of the plans, construction is expected to begin in the fall of 2008.
Project Cost Estimate
Engineering Design
Construction Engineering
Construction
$64,000
$65,000
$866,000
Total $995,000
Financial Analysis
Table 1 shows a summary of the financial aspects of the loan request. The Company shareholders
are a mix of agricultural, commercial and municipal owners; therefore the interest rate was
determined on a weighted basis based on share ownership (per the CWCB Financial policy #7).