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<br />provide,data to determine if there is excess seepage which requires <br />structural modifications. Presently the area is very wet but that <br />could be because of the flat land. <br /> <br />Most of the length of the south dike wilrrequire recontour- <br />ing to remove water that has ponded on or near the toe. The <br />ditches that exist to drain the ponds are not working and need to <br />be cut much deeper. Each of the three sections has a drainage <br />ditch. The ditches on the west dike and east and west sections of <br />the south dike will be able to carry 0.5 cis and the middle drain <br />'of the south dike will carry 1.0 cfs. Parshall flumes with six <br />inch throats will be installed at suitable locations on each of <br />the drains. <br /> <br />. .The rec.ontouring and drainage work can be accomplished by a <br />crawler tractor and backhoe. Staking and subsequent inspection <br />will be required on the areas that include drains and flumes. The <br />other areas have sufficient slope, such that the recontouring can <br />be done by visual inspection. The flumes will be installed <br />following completion of the earth work. <br /> <br />2. Raise Dike Crest ~ .The crest elevation of the dam and <br />dikes varies considerably. 'The highest portion is the first <br />quarter mile of the dam, beginning at the north end near the <br />campground, with elevations above 7403 feet MSL..' The remainder of <br />the dam and dike fluctuates between elevation 7400 and 7402 with <br />the exception of one location that is below.7400. The maximum <br />water surface is about 7397.6. <br /> <br />As part of the crest survey, permanent markers were installed <br />at about 200 feet intervals. the elevation of the top of the <br />marker and the dike at the base of the,marker was surveyed. In <br />later years the crest can' be resurveyed and the .elevations of the <br />markers checked to determine if the crest has sagged. <br /> <br />The required freeboard on reservoirs'the size of Summit is <br />generally three feet. This is sufficient to protect against over- <br />lapping from wave action. There are six locations on the crest <br />that have less than three feet of freeboard. Five locations are <br />on the west dike and total 620 linear feet. There is one location <br />on the south dike that is 240 feet long. (See Drawing V-D) . <br /> <br />Material for raising the crest will come from a borrow area <br />just west of the outlet works or the reservoir basin. The materi- <br />al will be excavated and hauled ~o the proper locations. Material <br />for the areas will be placed in one lift because the thickness is <br />about one foot or less. The material will be compacted with a <br />roller. No rocks larger than 1 1/2" diameter will be in the fill. <br /> <br />3. Backfill below west.outlet - Summit Reservoir has two <br />outlet pipes, east and west. The east outlet takes water from a <br />lower elevation than the west outlet and is used exclusively. The <br />west outlet is about 10 feet higher and has been unused for a <br />number of years. Presently the west outlet and the channel below <br />the outlet are in a state of disrepair. Summit decided that it <br />was more prudent to abandon the west outlet rather than repair it. <br />-25- <br />