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<br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br /> <br />This option of pumping directly from a point on Bear Creek to the Cooley Reservoir was <br />eliminated from further consideration due to high operation and maintenance costs as <br />well as the impracticality of pumping all water high up to Cooley Reservoir for use mostly <br />in the base pressure zone regions of Morrison. Pumping directly from Bear Creek at a <br />point nearest the treatment plant on Denver Mountain Parks land along the circular drive <br />(elevation 5850 feet) to the Cooley Reservoir an approximate elevation of 6457 feet <br />(according to the Haley & Aldrich report dated September 12,1994) would require a high- <br />performance, high-head pump to lift water up the 607 feet. With friction losses and a <br />pump efficiency of 70%, a total pumping power of approximately 267 horsepower would <br />be necessary. This would likely be satisfied with two pumps each at 150 horsepower. <br />Pumps this size would be costly, and therefore, extensive measures would be required <br />to minimize maintenance costs on the pump. Suspended sediment in the creek would <br />quickly damage the pump unless an efficient stilling basin was constructed at the pump <br />site. Operating costs are expected to be $67 per acre-foot or $33,600 total to fill the 500 <br />acre-foot reservoir, assuming a cost of $0.07 per kilowatt hour. Evaluating the cost of <br />a large stilling basin, high power requirements and other facilities to pump directly from <br />the creek to Cooley Reservoir, it becomes evident that a better location for a high head <br />pump to fill Cooley Reservoir is at the existing Morrison Operating Reservoir. The <br />Morrison Operating Reservoir is needed to act as a large stilling/flow leveling basin, and <br />it would be much easier from a permitting, operational and obtaining power standpoint <br />to locate the high head pump facility at the Morrison Operating Reservoir. <br /> <br />Note also that this option would require two sets of pumps and a separate pipeline if a <br /> <br />lower level treatment plant is used. <br /> <br />4. Use two diversion points: one gravity (the existing) and one lower intake which would <br />require pumping to the operating reservoir elevation. The option of maintaining both the <br />gravity intake and constructing a supplemental pumped intake on Bear Creek near the <br />treatment plant was eliminated when the computer model indicated the maximum <br />diversion rate allowed by the water rights and the modified capacity of the gravity intake <br />with improvements would be nearly identical. With adequate capacity in the gravity intake <br />system, there would be no need to construct a new intake. It has been pointed out that <br />the gravity intake may not be completely reliable due to the possibility of landslides and <br />rock slides. However, with the construction of the Cooley Reservoir a crisis situation <br />would be eliminated since Morrison would have enough water in storage to support <br />demand for a sustained period (depending upon the level of development) while the <br />gravity intake line is repaired. <br /> <br />70-080.035:Msrn-PLN <br /> <br />11I-6 <br />