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v """'3 ~' ,~ ~J Table 8, Mr. McLaughlin's Table containing information about artificial courses is interesting for several reasons. In fact, all of the courses listed in the table are built in artificial channels. None of these courses are subject to the same environmental, flood plain, and other constraints as a course constructed in an existing riverbed in the United States and therefore allow for a more constrictive geometry than that allowed in the Boating Park. As noted above, these courses are often so expensive that considerable pre-construction design work is justified in order to reduce construction and operation costs. Table 8 is also interesting in the context of the flows shown. The flows shown for the Dickerson course are solely determined by the cooling needs of the adjacent power plant and are therefore not relevant to this discussion. The low operating discharge at both of the remaining courses corresponds to flows used for beginning kayaking, inflatable and raft traffic. Competitive events, daiiy kayak training, and rafting take place at the upper level of flows shown in this Table. This occurs in an operational model similar to the one proposed for the RICD on the Yampa River. A key fact that relates flow rates in Table 8 to flow rates in the Boating Park is that, at flow rates labeled as "Competitive Discharge" in Mr. McLaughlin's Table 8, flow depths are similar to those flow depths at the Boating Park at the upper range of the requested RICD. It is significant that Mr. McLaughlin does not cite the only in-channel whitewater park he has designed, the 1996 Olympic Course on the Ocoee River in Tennessee. This multi- million dollar whitewater park is not included in the list in spite of the facts that 1) every other Olympic Course is listed, and 2) this Whitewater Park, like the Boating Park and unlike any of the courses he cited, is located in a natural channel in the United States. The difference between a constructed artificial course and a course in a natural river channel is important to this discussion. Mr. McLaughlin has compared apples to oranges. In an artificial channel the channel shape need only consider the specified amount of flow. For these types of courses the dimensions of the channel can be tailored to exactly fit the supplied flow. In a natural channel the structures must be subtler and more expandable. As shown in my earlier January 2004 report, low and high flow channels are 20