Laserfiche WebLink
<br />tunnel between the dam and the treatment plant) not be built <br />but that delivery of water to the treatment plant be made by <br />way of an existing tunnel owned by the City of Aurora (Rampart <br />Tunnel No.2) which would have to be modified and improved <br />to accommodate both Denver's and Aurora's present needs, <br />with a parallel tunnel being required later to accommodate <br />Denver's full demand for a 500 mgd plant. <br /> <br />It is significant to note that Mr. Sherman's idea was <br />not novel. Both Denver and Aurora recognized the possibility <br />as early as 1964 when the two cities entered into an agree- <br />ment giving Denver the right to make such a use of the <br />tunnel. Thereafter, Denver initiated evaluations of the <br />possibility which led to a report dated October 24, 1966, <br />which rejected the possibility (See Exhibit 3). Denver <br />conducted a second and more detailed evaluation of the <br />concept in 1971 after the tunnel was completed, and again, <br />in March of 1971, rejected it because of excessive costs and <br />technical difficulty (See Exhibit 2). <br /> <br />In explaining their analysis of the work needed to be <br />done on the Rampart Tunnel and the resultant costs, repre- <br />sentatives of the United States Bureau of Reclamation <br />indicated that their work was done on the assumptions that: <br /> <br />1. The geology of the tunnel was adequate: <br /> <br />2. The existing lining could be pressurized rather <br />adequately: <br /> <br />3. Slow closing valves would be used to avoid having <br />to construct a surge chamber; and <br /> <br />4. The work could be done in five-month increments <br />with Aurora receiving no water service during those periods. <br /> <br />They have acknowledged that they had given no consideration <br />to the fact that filter plant operation does not permit the <br />use of slow closing valves; indeed, their entire discussion <br />revealed a total ignorance of water utility operating problems. <br />As a result of these erroneous assumptions, cost estimates <br />made by the United States Bureau of Reclamation for the <br />improvements to the tunnel are necessarily distorted and far <br />too low. <br /> <br />ERRONEOUS U.S. BUREAU OF RECLAMATION ASSUMPTIONS <br /> <br />1. Geology <br /> <br />Aware that assumptions concerning the geology of the <br />tunnel could be misleading, Denver sought the advice of a <br />nationally recognized geologist and professor at the famous <br />Colorado School of Mines who had personal knowledge of the <br /> <br />-8- <br />