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I. I I I I I I I I I I I I I I I I I I Of)Z34~ Executive Summary Reservoir was drawn down each year due to hydropower operations in an amount of approximately 7,000 af, Under 2015 demand conditions the storage in Stagecoach was used infrequently, In the long-term demand scenario (2040) that includes the enlargement of Stagecoach Reservoir, Stagecoach was drawn down an average of 7,365 af per year as additional releases were made out of its enlargement pool, The average drawdown of Elkhead Reservoir in this scenario was approximately 17,000 at Instream Flow Conditions at Juniper Canyon Table S-9 shows the modeled average monthly flows (cfs) in Juniper Canyon under the No Action, 2015 and 2040 demand conditions, Minimum flow conditions typically occurred in the months of September through February, Table 5-9 Average Modeled Juniper Canyon Flows (ers) October November December January February March April May June July August September No Action 2015 2040 With Phased Enlargements 2015 2040 329 306 253 234 277 603 2,501 5,537 4,794 1,102 276 191 321 279 226 206 246 572 2,460 5,484 4,732 1,032 221 181 325 308 255 236 278 595 2,368 5,515 4,799 1,134 323 243 272 275 233 212 250 567 2,304 5,400 4,736 1,106 296 175 Recovery Program Integration and Recommended Flows An important criteria in evaluating near-term and long-term water development projects in the Yampa Basin was the effect of future development on streamflows in the Yampa River at Deerlodge Park. While transfer of a portion of the Juniper Project water rights to instream flow purposes at Juniper Canyon may be an important step towards protecting the habitat needs of the endangered fishes, depletions associated with future water uses were evaluated to assess their effects on the hydrograph of the river, A review of the future basin demands used to establish the interim flow recommendations suggested that the interim flow recommendations were based on a demand horizon which falls somewhere between the years 2015 and 2040. For this reason it was deemed more logical to focus on comparisons between flows predicted under near- and long- term projects and the No Action alternative, rather than the interim flow recommendations, This comparison is provided in Table S-9, which suggest that the effects of enlarging and operating Elkhead and Stagecoach Reservoirs will be to slightly reduce Juniper Canyon flows during the early runoff period and to slightly increase flows in the remainder of the year, S-3l j:-~;)'I