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Need for the Project <br />The WVDC is undertaking upgrades to their Cottonwood Draw flume <br />to ensure that it can continue to divert water to the lower third <br />of their system. The WVDC currently has two flumes used to convey <br />water over other waterways. The first flume on the Weldon Valley <br />ditch is the Jackson Lake flume. This flume diverts WVDC water <br />over the outlet canal of the Jackson Lake Reservoir. This flume <br />has undergone upgrades and repairs back in 2000. The second flume <br />on the Weldon Valley ditch is the Cottonwood Draw flume which <br />diverts water over the Cottonwood Draw. These two flumes are <br />critical components for the delivery of water to the WVDC <br />shareholders. The Cottonwood Draw flume is the focus of this <br />study. <br />The Cottonwood flume is a metal channel (half pipe) supported <br />with large wooden members bracing up the channel at multiple <br />locations through the Draw. The current flume was built in 1965 <br />after the original structure was destroyed in a flood. In 1991 a <br />synthetic liner was added to the channel to prevent corrosion of <br />the metal and thus extending the life of the flume. Excessive <br />wear and tear on the liner caused the Company to remove what <br />remained of the liner in 2007. The wood supports are also <br />experiencing failure due to their age along with failure in the <br />foundations of the supports. Support and foundation failure at <br />the east end of the flume are starting to disrupt the flow in the <br />channel. Due to the nature of its construction, the flume is <br />still very susceptible to flood damage. <br />Alternatives Evaluated <br />A range of alternatives were considered including 1) don't build <br />the project, 2) perform remedial repairs on the existing flume, <br />and 3) replace the existing flume with a siphon. <br />An evaluation of the alternatives follows: <br />1. Don't build the project: <br />If the project were not pursued, the WVDC would leave the <br />existing flume in place and continue operating their system <br />like normal. Due to the deteriorated condition of the flume, <br />it is not a matter of if it will fail but when it will fail. <br />A failure of the Cottonwood Draw flume would mean that half <br />of the Company's shares could not be delivered. This <br />alternative is not acceptable to the Company. <br />Feasibility Study <br />Weldon valley Ditch Company <br />Cottonwood Draw Flume <br />September 2008 <br />