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0111170 33 Maximum capa.;jty of the Staget:oacl1 outlet works is 450 cfs, Additional water may be drawn from the reservoir through a penstock and power hOllse at a maximum ~alc 'of 109 cfs. In the model, reservoir releas~s are rOUled first through the penstock up to its capacity of 109 cis. Stagecoach Reservoir is currently operated so that an average drawdown of 10 to 12.feet occurs during the fall and winter months. This translates to approximately 7,000 af if the drawdown is initiated when the reservoir is full. This is done in order to generate power, accommodate spring inflows, and avoid reservoir spills. The reservoir has generally refilled by the end of July. These drawdown operations are not currently operated in the model but may be represented by adjusting fall and winter month storage targets or by ,imposing a higher minimum release La simulate power operations. Steamboat lake Steamboat Lake is owned and operated by the Colorado Division of Parks (DOP). Total capacity of the reservoir is 26,379 af, including j,:, 11 af which may be stored if the reservoir is operated up to the level of its emergency spillway. The DOP has operated the reservoir in such a manner for the past several years, This additional water has been released on an informal basis to augment flows in the Yampa River during low flow periods, gencrally in the carly {'all months. The DOP is in the process of formalizing a lease agreement with the USFWS to continue t(> SlOre and release this additional water. Ownership in Steamboat Lake by Colorado Ute is 5.000 af. This water has historically never been used. The remaining capacity of the reservoir, 18,068, is currently uncontracted and has been used as a recreational pool. although ir might be assumed active a.nd available to meet downstream demands. However, it should be noted that Steamboat Lake is a very popular recreational area; although there, is no formal commitment to maintaining the water level of the reservoir, nop personnel have indicated that the reservoir has been operated in such a manner. Accordingly, the represen'tation of active and inactive storage in the model is accomplished using the following storage targets: Colorado Ute Augmentation flow Recreation Pool 5,000 af 3,311 af 18,068 af Total Cap'aeity 26.3 79 af I The Colorado Ute account has not been used in the past but contractually is available to serve only the Hayden Station water requirements. At this time the recreation pool is modeled as inaccessible to any demands. If the results of model runs show significant shortages, access to the recreational pool might be reconsidered. The j,:,11 af pool available to augment flows in the Yampa River will be used only in the months of September and Oc.tober. Although the current augmentation agreement uses 2,.000 af of this amount, discussjons with DOP suggest that a conservative but reaiistic assumption is that the entire 3311'afis used annually for flow augmentation. Maximum capacity of the outlet works is 725 crs; Steamboat Lake has no' power generating facilities. There are several instream flow filings on the Elk River and Willow Creek, Willow Creek enters the Elk River in the reach between the North Fork of the Elk River and Rock Cret'k. Those filings below Steamboat lake include: .';r,,-_.