Summary Testimony Provided by Gary Lacy for Eagle River and Sanitation District

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The structures are designed to divert and control the flows to create whitewater boating features, particularly at high flows. These structures function even if they are partially or completely inundated. I designed the Course to work the best at 400 cfs. This flow rate was based upon numerous factors, including the physical parameters of the stream channel, my working knowledge of Gore Creek, hydraulic formulas, the purpose to be served by the Course, and the available flows. Basic hydraulic formulas were used to determine the necessary design parameters of the structures to ensure complete control of the stream flow at 400 c.f.s. and higher, and to provide low flow passage as discussed below.. The design of the structures are such as to produce the optimum waveforms at flows of 400 c.f.s. and above. Structures included in the Whitewater Course include "U" drops and "V" drops. Each of these is followed by a self - scouring pool. These structures are designed to divert and control the flow at specific points to create surf waves, rodeo holes, standing waves, eddies, and j ets of water for squirt boating. As water flows increase, these wave forms become larger, more powerful, and conducive to the sport of whitewater rodeo, playboating, and slalom racing. The structures also work in tandem to create the desired features. All of-these features provide a better boating experience at the higher flow rates at 400 cfs, and therefore draw more boaters at those rates. The Course also works to allow passage during low flow. The structures and their elevation/configuration were designed to provide depth for boating during very low flows, even when the whitewater wave features are not present. This is best demonstrated by the continuing use of the Course at low flows. This low flow passage is an important improvement over the pre - course condition. Gore Creek is now navigable through the Course at low flow rates where passage was not possible in the pre - course condition. The low flow passage is now possible by diverting all of the stream flow through a low flow channel to allow boat passage. At higher flows, the water fills the high flow channel which, as discussed above, is designed to control and divert the entire high flow to create the desired whitewater features. I will prepare plan, profile and section view drawings of certain representative structures to help explain how the structures create the desired wave forms at high flows and allow passage at low flows. In addition, I have personal observations to demonstrate how the Course is working. In summary, though natural in appearance, the area of Gore Creek through the Course is now a highly engineered system of diversion dams and drops that completely control the water for whitewater boating, and this area of Gore Creek is no longer a natural environment. Lacy Report Page 2