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determine the width of the opening to maintain 2 feet of depth. Using • <br />Equation 2 above and solving for L <br />L = -Q (2) <br />3.3 * h3?2 <br />Because approximately 100 cfs is passing through the low flow opening, Q in <br />Equation 2 is 500 cfs, for a total flow of 600 cfs. Therefore, the opening for <br />the high flow rate is 54 feet. This width, along with the depth and flow rates, <br />conforms to commonly accepted design practice for white water kayak <br />courses. This is discussed further in Mr. Lacy's testimony. Control <br />structures narrower than this width would not create the downstream wave <br />characteristics required for an adequate white water recreational experience. <br />High flows are requested for three, three-day weekends (Memorial Day, <br />Independence Day, and Labo:r Day) and for daylights hours (7:00 am to 8:00 <br />pm). These dates and times a.re consistent with the Town of Silverthorne's <br />plans to create event oriented recreational experience in the Blue River <br />h. Frequency and Duration of Requested Amounts of Water for the <br />RICD <br />As shown in Exhibits I, J and K, there are sufficient unappropriated flows • <br />available for diversion by the Course to,meet the goals and objectives for the <br />Course. <br />Historical average monthly flows in the proposed reach of the Blue River for <br />the Course are presented in Exhibit I for the period, October 1, 1986 through <br />September 30, 2004. These data show that, historically, the requested low <br />flows (100 cfs) are available. Exhibit J provides the number of days per <br />month that flow greater than 1100 cfs were historically available for this time <br />period. The period (May - Sf;ptember) and times (7:00 am to 8:00 pm) <br />requested will minimize the ilnpact on exchanges upstream of Dillon <br />Reservoir. Exchanges can be made during the winter months or during the <br />nighttime hours in the summer without any effect from the Silverthorne <br />RICD. Exhibit K presents the; number of days per month for the period <br />October 1, 1986 to September 30, 2004, during which the flow was greater <br />than 600 cfs in Blue River below Dillon Reservoir. Figure L presents <br />historical flows for the May 1 to September 30, 2004 period. In September, <br />the flows averaged 400 to 500 cfs for the Labor Day weekend. These higher <br />flows results from an offer by Denver Water in 2004 to coordinate releases <br />from Dillon Reservoir to Green Mountain Reservoir. This offer by Denver <br />Water allowed the Town to plan events for the 2004 Labor Day weekend. <br />These higher flows indicate triat periodic, planned increased releases are <br />possible from Dillon Reservoir even during historically low flow years. These <br />high flows have the added betiefit of flushing the Blue River which can be • <br />beneficial to fish habitat.