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<br />e <br /> <br />e <br /> <br /> <br />The upstream concrete face of the existing embankment would be <br />removed and if possible stockpiled for use as rip rap on the <br />enlarged dam. Also the pipeline on the north side of the <br />embankment would be removed and replaced if needed. <br /> <br />The dam would be raised by placing material on the upstream face. <br />The downstream slope includes a toe drain that was installed about <br />15 years ago and a pond, both of which must be removed if the <br />enlargement fill is placed on the downstream face. Also, the <br />concrete face is a structural concern which should be removed. <br /> <br />The downstream slope of 2.0H:1.0V would be extended upward at the <br />same slope, an additional height of 8 feet. The crest would be 21 <br />feet wide then the upstream slope would be placed at a 3.5H:1.0V <br />slope, extending about 100 feet further into the reservoir. The <br />material between the toe of the existing and new embankments must <br />be excavated down to suitable material. A core trench 20 feet <br />deep, 20 feet wide would be excavated most of the length of the <br />embankment and upstream of the centerline of the embankment. If <br />there is any unsuitable material, e.g. excess rocks or humus, the <br />material would be wasted near the reservoir. <br /> <br />The volume of fill to enlarge the dam is estimated by determining <br />the volume of the existing embankment, Table 2, which is subtracted <br />from the volume of the enlarged embankment, Table 3. The volume <br />difference is increased by 30% to account for compaction. <br /> <br />Embankment material would be obtained from a 40 acre parcel of land <br />east of the dam, owned by the District. The borrow area is <br />expected to be impervious material so that the entire enlarged <br />embankment will be the same impervious material. <br /> <br />The material would be <br />Proctor. Adequate <br />compaction. <br /> <br />placed in lifts and compacted to 95% Standard <br />testing will be required to monitor the <br /> <br />The concrete facing on the darn is assumed to be suitable for rip <br />rap on the face of the enlarged dam. <br /> <br />The existing toe drain will be used to control seepage through the <br />embankment. <br /> <br />OUTLET PIPE: The existing 34 inch diameter steel outlet pipe will <br />be extended about 100 feet to the upstream toe of the enlarged <br />embankment. The operator chamber will also be extended about 10 <br />feet to the crest of the enlarged embankment in order to operate <br />the existing gate. <br /> <br />prospect Dam <br /> <br />7 <br />