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• above. As a concession to Staff on this issue, Silverthorne, as discussed above, has agreed to <br />incorporate trigger flows in any decree that it seeks in this case. <br />B. Appropriate stream reach. <br />Only the CWCB Staff, and no actual water users, contest whether the stream reach at <br />issue is appropriate based on flooding potential and stream access. With respect to flooding <br />potential, Staff asks the Board to make a finding that the Blue River Whitewater Park is not <br />within an appropriate reach of the Blue River because Silverthorne has not demonstrated that the <br />RICD structures do not adversely impact the flood plain. (Staff Prehearing 5tatement at 3.) This <br />is not a legitimate reason to recommend against the Silverthorne RICD. Flood control issues <br />have never been a basis to deny a water right. Every traditional direct flow diversion, not to <br />mention every storage facility, potentially impacts the flood plain. Though such impacts should <br />certainly be considered in the appropriate context, they are the subject of different regulatory <br />regimes and simply have never been an issue in the appropriation of water rights. The plain <br />language of section C.R.S. §37-92-102(6)(b)(II) directs the CWCB to make a finding concerning <br />the "appropriate reach of stream required for the intended use." (Emphasis added.) The plain <br />language requires only that the CWCB make a finding on whether the stream reach is <br />appropriate when tested against the purposes for which the RICD is claimed. As an aside, we <br />find it somewhat ironic that the implication of the Staff s position is that absent the Staff's <br />oversight, that Silverthorne would mindlessly build structures in the River that would flood the <br />Town. We believe that the CWCB can rely on the enlightened self-interest of the Town, not to <br />. mention common sense, to prevail. <br />Moreover, as indicated in the attached Rebuttal Testimony, Brown and Caldwell has <br />concluded that there is no chance that floodplain regulations will be violated by the RICD <br />because: <br />The structures will be designed to meet all applicable floodplain regulations. They will <br />not be permitted for construction unless they meet these regulations. As depicted in <br />Silverthorne Exhibits F, G, and H, the structures will each consist of a grouted-rock <br />control section and an excavated pool immediately downstream. The grouted-rock <br />control section will not project significantly into the existing channel cross section during <br />high flow events. <br />• Numerous similar structures that do not impact 100-year water surface elevations have <br />been constructed in Colorado and other states. <br />• The 100-year water surface profile at the project site is partially controlled by backwater <br />from the Highway 9 river crossing just downstream of the site. The 100-year water <br />surface profile of the Blue River upstream of the Highway 9 crossing is controlled in part <br />by the conveyance capacity of that crossing. Review of the FEMA flood insurance study <br />for this reach suggests that backwater caused by the Highway 9 crossing propagates <br />upstream during the 100-year flood event into at least part of the reach in which the <br />• proposed structures will be constructed. Preliminary review of hydraulic modeling for <br />design of fish habitat just upstream of the Highway 9 crossing tends to reinforce this <br />2