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Executive Summary summer months. This corresponded to minimum storage of 35,000 of during June, July and August. A recreation pool of 16,400 of was defined at Stagecoach to be consistent with historical operating criteria. Although there is not a minimum release requirement below the existing Elkhead Dam, a minimum release of 10 cfs or inflow was defined in this Study for the enlarged reservoir. An existing release requirement below Stagecoach of the minimum of 40 cfs or the reservoir inflow was also represented. This Study defined the Juniper Project contemplated draft (adjusted to consider the drafts of existing reservoirs) as an instream flow right at Juniper Canyon. Water Supply Several model revisions and sensitivity tests were made which were designed to test the effects of various reservoir operating criteria imposed on the recommended enlargements. The final results of the revised model runs are presented in Tables S-6 through S-8. Table S-5 shows the shortages to demands under the 2015 and 2040 demand conditions with only the development of the 46,500 of Elkhead Reservoir. As shown in Table S-8, with the development of the Stagecoach Reservoir enlargement to 52,000 af, most of the 2040 demand shortages were eliminated. Table S-6 compares the water delivery shortages in these final model runs with those generated in Scenarios III and IV. As can be seen, the imposition of more specific minimum release and recreation pool operations at Elkhead had relatively little effect on modeled shortages. Table S-6 Comparison of Delivery Shortages Between Initial and Final Model Runs Assuming Phased Enlargement of Reservoirs Demand Category Scenario III Scenario IV Final Runs Potential 1989 Maximum 5,841 * n.a. 6,595* Average 1,955* 1,368* Projected 2015 Maximum 6,413* n. a. 7,167* Average 2,084* 1,532* Projected 2040 Maximum n.a. 6,629 7,153 Average 247 255 * = With near-term project only Reservoir Water Levels Figures S-4 and S-5 show modeled reservoir contents over the study period for the 2015 and 2040 demand conditions, respectively. Under 2015 demand conditions with only the enlargement of Elkhead Reservoir, Elkhead was drawn down an average of approximately 10,000 of each year; this drawdown typically occurred in the month of February. Stagecoach S-26