Laserfiche WebLink
IL <br />Memorandum <br />January 3, 1992 <br />Page 4We- -c M re-e. <br />,Yand bedding. Additionally, the floor and sidewalls of the channel should be armored <br />with riprap for the first 50 feet or so. It would not be necessary to remove either the <br />existing boulders across the channel inlet or the timber crib overflow section buried <br />in the channel floor. The riprap should be keyed into the channel bottom at the <br />downstream end. Total cost for excavation, riprap, and bedding at anticipated area <br />prices, would be about $20,000. <br />If additional protection for the channel were desired, rock riprap could be placed over <br />the entire reach of the channel from the overflow to the county road bridge, a distance <br />of about 110 feet. This could be done for a total cost of about $40,000. <br />It should be noted that, according to Bob Hurd, Hinsdale County Road Dept. <br />Supervisor, private interests own all of the lake shore at the outflow area. To lay back <br />the channel inlet slopes at 3:1 would require encroachment on that property, all of <br />which is unimproved. The costs, if any, associated with that are not included in the <br />above. <br />If no immediate action is taken to stabilize the channel inlet, as a minimum, the <br />existing boulders across the channel inlet should be removed to provide needed <br />capacity, to lower the water surface on the crib sidewalls, and to reduce turbulence <br />and scour at the crib overflow structure. <br />DM /dbr <br />dr0090.mem <br />