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I I I I I I I I I I I I I I I I I I I 3 moved adequately through the wave without any noticeable bow or stern hits. Recreational boaters are not on the river at rates in excess of 1,500 cfs. However, when the flow was in excess of Z ,000 cfs, Gary Lacy felt the wave would provide some sport for expert kayakers (not rec reational boaters). These improvements to the boating charecteristics also allowed USBR personnel to shorten the length of chute needed and eliminate additional rock on the face of the existing USACE dam. This will tend to control the cost of construction. USACE DAM CREST At all flow rates tested, 30 cfs was being removed through the Englewood intaKe. At a flow rate of 300 cfs in the river upstream, only a slight tricKle of water was overtopping the dam crest. At flows up to 1,000 cfs, all canoes, kayaks, and rafts would hang up on the dam crest, either on the sill or on the rOCKS immediately downstream of the sill. However, the placement of the sill greatly improved the flow characteristics over the dam crest from what had been observed previously without the sill in place, i.e., with only rocks in place downstream of the dam crest. The sill eliminates the keeper wave that existed with flow rates less than about 1,500 cfs. Several participants were involved in placing boats of various types over the crest and observing their actions at the several flow rates tested. The conclusions reached by the participants were twofold. 1. The sill definitely improves the flow characteristics over the existing dam crest. Z. The rocks immediately downstream of the sill should be smaller and grouted in place. The surface of these rocks should be fairly smooth so that the boats can ride over the tops of them and not get hun9 up. These rocks should be carried downstream to the point that the tailwater provides sufficient depth to allow the boats to continue on their way.