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Table 16. Continued. Reservoir Salvage Percent Cost Volume Volume Suppression ($/ Acre feet) Basin Reservoir (Acre feet) (Acre feet) 10 Ash Creek 9928 77 13.9 32.75 9 Lake Powell 27162000 152.264 31.2 .39 8 Joe's Valley 62500 268 18.5 19.82 10 Gunlock 10884 156 16.9 16.93 4 Total with costs under $5 Total with costs under S5 5 Total with oosts of $5 to S10 10 Total with costsofSlO 10$20 10 Total with costs oC $20 to $40 205.969 (seasonal model) 162.589 (long term model) 4.639 3.185 969 There are 29 reservoirs in Utah (Table 16) which have the potential for water salvage at costs under $40 per acre foot (1970 dollars); 19 reservoirs under $20; 9 reservoirs under $10 and 4 reservoirs under $5. The major quantity of salvage would be in the under $5 category because it includes the major reservoirs. Powell. Flaming Gorge. Bear Lake and Strawberry. Bear Lake. or course is deleted in the long term analysis because its suppression would be only temporary, as discussed previously. The regression equation for costs indicates very large economies of scale for Lake Powell ($0.39 cost per acre foot). An extrapolation this far out of the empirical da:a range is probably not accurale and a cost of $1 to $2 would likely be more reasonable for Lake Powell. Since Powell represents the major potential in the state, a more detailed discussion of the probable costs and benefits of destralifying Lake Powell is given in a separate section. The flaming Gorge cost of $1.51 is ;;"ely also too low because of a significant extrapolation. The volume of flaming Gorge is 3.8 million acre feet while the largest impountment included in deriving the cost function was 0.5 million acre feet. Strawberry reservoir at 0.87 million acre feet represents only a slight extrapolation and is computed al $2.81. It is likely that a reasonable cost to expect on flaming Gorge is $2.00 to $2.50. Several smaller reservoirs have costs which would likely make destratification cost effective. The five reservoirs with costs between $5 and $10 are Pineview, Deer Creek, Starvation. Sevier, and Mona. In the Weber Basin there is a current surplus of water making the $7.37 cosl at Pineview of questionable feasibility; however, $8 to $10 costs in the two Sevier Basin reservoirs should be lower than the marginal cost of water there. There are several other reservoirs included in Table 16 which have costs which appear to be lower than the value of the water salvaged. for example, the value of water in the Virgin River Basin is undoubtedly higher than the $17 cost at Gunlock Reservoir and probably also higher than the $33 at Ash Creek. Several of the $10 to $20 costs are at reservoirs in the Weber and Bear River Basins. The marginal value of irrigation water in both of these basins is presently less that $20 and probably less than SIO at most reservoirs. Lake PoweU cost effecdveness As discussed previously, a reasonable cost of salvaged water at Lake Powell appears to be $1 to $2 per acre foot. Using the higher figure, the cost of salvaging 140,000 acre feet annually would be $280,000. If this water is worth $10 per acre foot, the net profit of such an operation would be $1,120,000 per year. Since destratification of Lake Powell would require a large amount of energy. an interesting aspect of such a project is the impact on the energy supply/demand quantities of this area. Extrapola- lion of the energy demand curve given in the Symons report (1971) suggests that compressors or pumps totaling 3200 H.P. would be required to destratify Lake Powell. Because of uncertainties in such an extrapolalion, 6,000 H.P. will be used in the following analysis as a conservative estimate of the energy requirement. The annual model for Lake Powell indicates thaI 6 months of continuous pumping would be required for optimum results. 46