Letter to CWCB Members May 10 2005 Re RICD For Buena Vista and Salida, Caffee County, Arkansas River

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Colorado Water Conservation Board Members Mr. Thomas Browning, P.E., CWCB Review of Lacy Report for Chaffee County Whitewater RICD May 10, 2005 Page 5 of 9 reaches? Would a commercial rafter, private rafter, recreational or competitive kayaker come to use this reach, when other river segments may not be boatable? What is the flow ranges when this would occur? Could the design in the RICD reach be optimized for conditions when low flows severely restrict usage elsewhere, thereby help to sustain boating activities and income in the region, and still provide a great boating experience during high water? Are there design features which can be incorporated to mitigate the problems and/or provide a satisfactory design with less flow? Is there a design trade -off where lesser flows can be used at the expense of loss of isolated major competitive events? Can freestyle or slalom competitive events be held at alternative locations along the Arkansas, under lower flow conditions? Can special releases be arranged for such events, rather than a sustained flow of 1,800 cfs for one and a half months? Are there other natural reaches where competitive events can be provided that are more appropriate? Is the site a realistic candidate for high level competition when there are inherent limitations to creating the fall, length and character needed without impacting flood levels, properties, or infrastructure? Would there be a higher usage level with features and flows that served a greater percentage of the potential or existing users, and for longer periods of time? Questions such as these aren't addressed, thus the design is not adequately substantiated and certainly not optimized. There are viable alternatives to the Lacy design. For example, the Lacy schematic design calls for a wide weir cross the entire waterway. This approach has disadvantages of creating shallow flow across the entire waterway that in effect reduces stream power for much of the waterway while raising flood levels. It inherently requires more flow than other feasible designs to achieve quality and competitive boating conditions. More satisfactory boating could be provided with narrower, deeper notch(s) and other features. Besides the shallow flow problem over the structure, the weir section shown will allow flow to drop to the river bottom, potentially forming a keeper (submerged hydraulic jump that can traps floating objects, including upsetting boaters). The sketch shown will result in flow diving to the bottom along the entire weir, which isn't reasonable for hydraulics or safety of the typical boater. C13 12596 WEST SAYAUD AVENUE, SUITE 200, LAKEWOOD, CO 80228 303.458.5550 FAX 303.480.9766