Laserfiche WebLink
<br />2 <br /> <br />chute and rock on the existing dam face required that this wall be raised. Subse- <br />quent operation of the model and changes to the rock configuration have eliminated <br />the need to raise this wall. Removal of this increased wall height does not affect <br />the flow characteristics for boating. One result of this change is to help control the <br />construction cost of the project. <br /> <br />The dam crest had been modified by installing a sill along the dam length, located <br />just downstream and below the existing crest. Smaller rocks (about 3 feet in dia- <br />meter) were placed just downstream of the sill. This improves the flow patterns if <br />boaters inadvertantly go over the crest itself rather than through the boatchute at <br />higher flow rates. The design is based on boaters only going through the chute, but <br />the dam crest provision represents prudent care for potential mishaps. <br /> <br />The partiCipants then viewed the operation of the boatchute and Englewood intake <br />through the range of flows from 50 cfs to 3500 cfs. Throughout this entire range of <br />flows, 30 cfs was being withdrawn from the flow through the Englewood intake. <br />Their comments and observations on various aspects of the proposed improvements <br />are listed in the following pages. <br /> <br />BOAT CHUTE AT EXISTING USACE DAM CREST <br />The current modifications to the boat chute by USBR personnel have resulted in a <br />chute which has the same flow pattern throughout the entire range of boating flows. <br />At flows less than 1,000 cfs, the flow is smooth through the chute with only a minor <br />wave at the point where the flow through the chute meets the tailwater. At flow <br />rates from 1,000 cfs to 3,500 cfs, the wave gets larger and is about 3 feet high at a <br />flow of 3,500 cfs. A 3-foot standing wave is too high for recreational boaters. In <br />1984, Wright Water Engineers recommended that peace officers close the river to <br />recreational boaters at 1,500 cfs. <br /> <br />At all the flow rates, several types and sizes of canoes, kayaks, and rafts were <br />floated through the boat chute. In all cases the boats floated straight through the <br />chute and continued downstream. At flow rates of 2,000 and 3,500 cfs, all boats <br />