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<br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br /> <br />5. Inadequate freeboard to fill to Gage Height 24 feet. <br /> <br />The general overall condition of the embankments and their <br />foundations is good with no serious problems. The embankment and <br />the foundation are composed primarily of clays and weathered <br />shales with no sand or gravel layers found by the investigations. <br /> <br />Considering the problems noted above. three alternatives were <br />developed to provide a range of choices and solutions to the <br />problems noted. Cost estimates were prepared for each alternative <br />utilizing all existing information and the information developed <br />for this report. The costs are based upon the bid costs for Clark <br />Lake and other similar projects in the area. A 30% factor for <br />engineering, legal fees, and contingencies are included in the <br />cost estimates. The principal features of each alternative and <br />their costs are summarized as follows. <br /> <br />Alternative <br /> <br />Description <br /> <br />Estimated Cost <br /> <br />1. Raise the dam to Gage Height 29.0', flatten <br />the upstream and downstream slopes to 3 to 1, <br />replace the outlet. provide a toe drain, <br />riprap and bedding, and construct 250 wide <br />spillway. <br />A. <br />B. <br /> <br />Spillway Located At West Dam <br />Spillway Located At East Dam <br /> <br />$621,643 <br />$744,451 <br /> <br />2. Same conditions as <br />except flatten the <br />to 4 to 1. <br />A. <br />B. <br /> <br />alternative 1 above <br />upstream slope <br /> <br />Spillway Located At West Dam <br />Spillway Located At East Dam <br /> <br />$689,860 <br />$812,668 <br /> <br />3. Raise the dam to Gage Height 34.0' to in- <br />crease the storage by 3367 acre-feet, <br />4 to 1 upstream slope, 3 to 1 downstream <br />slopes, replace outlet. provide riprap <br />and bedding. provide a toe drain, and <br />construct a 250 foot wide spillway. <br />A. Spillway Located At West Dam <br />B. Spillway Located At East Dam <br /> <br />$1,077 ,978 <br />$1.134,615 <br /> <br />SMITH GEOTECHNICAL recommends Alternative 1.A above for a <br />total estimated cost of approximately $622,000. This recommenda- <br />tion is based on the total cost plus the fact that no right-of-way <br />will have to be purchased. Also. the additional cost of $68,217 <br />to flatten the upstream slope to 4 to 1 to go from Alternative No. <br />1 to Alternative No. 2 is not worth the extra cost to reduce the <br />long term riprap maintenance costs. The 4 to 1 slope is not <br />required for stability but was included as an alternative due to <br />the positive effect the flatter slope has on long term riprap <br /> <br />ii <br />