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Pathfinder Municipal Account <br />(Average yield = 4,800 acre-feet per year at the reservoir) <br />The input to the North Platte River EIS model was modified such that the municipal demand is <br />4,800 acre-feet per year. The demand is 9,600 in dry years, 0 in wet years and 5,664 in the <br />remaining years. The annual flows into Seminoe Reservoir for 1941-1994 were ranked from <br />lowest (1954) to highest (1984) and the top 33% were considered wet and the bottom 25% were <br />considered dry. After determining the Pathfinder Municipal demand, the remaining delivery <br />(9,600 minus the municipal demand) was made available to the program and delivered in <br />September. <br />Glendo Storage <br />(Average yield = 2,650 acre-feet per year at the reservoir) <br />The North Platte EIS model has a demand for the 10,600 acre-feet of Glendo conservation <br />storage. In order to provide water for the Program, an additional demand had to be put on the <br />system. The Program would not receive any storage during dry years as described above. In the <br />remaining years, the Program could take up to the difference between the existing demand and <br />the maximum 10,600 acre-feet delivery. In order to achieve a yield of 2,650 acre-feet at the <br />reservoir, approximately 50% of the difference was delivered to the Program. <br />Water Leasing <br />(Average yield is approximately 8,200 acre-feet per year at the reservoir) <br />Given the declaration by the Water Committee that water leasing should be tied to storage, water <br />leasing in reaches 1, 2, 3, and 4 was concentrated in the Kendrick Project. In order to achieve the <br />reduction in consumptive use of approximately 6,100 acre-feet, the deliveries to the Kendrick <br />Project were reduced by 17% or around 12,200 acre-feet per year. This incorporates the <br />assumption that approximately 50% of any diversion returns to the North Platte River, which is <br />different from Boyle's analysis. Boyle's analysis includes conveyance losses which are <br />considered to be 100% consumptive use. The EIS analysis uses the assumptions that are <br />included in the North Platte River EIS model, which are that 50% of any diversion returns to the <br />river. Water leasing in reach 6 is assumed to be tied to the storage associated with the Wheatland <br />Irrigation District and the consumptive use portion of the leasing is added as an inflow to the <br />North Platte River EIS model at the Laramie River. <br />CENTRAL PLATTE RIVER EIS OPSTUDY MODEL <br />CNPPID Re-Re u??lating Reservoir <br />("Score" = 6.2 kaf) <br />Following receipt of Central's Depletion Mitigation Study Phase I(HDR Engineering, Apri17, <br />2000), Boyle advised using the J-2 Forebay project as an example project with a capacity of <br />3,436 acre-feet. The project included an inflow rate (when instream flow excess existed at <br />Overton, Grand Island, and the J2 return) of 100 cfs to the reservoir, and an outflow rate of 50 cfs <br />whenever shortages were occurring. In the monthly OPstudy model, the average annual release <br />was approximately 3,100 acre-feet. Based on EI5 team comparisons of monthly and daily flow <br />data for a reregulating project in the vicinity of the J2-Forebay area (and the size of the inlet & <br />outlet), the EIS team scored this project by multiplying by a factor of 2.0. This resulted in a <br />"score" of 6,200 acre-feet for this example project.