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I I I I I I I I I I I I I I I I I I I reservoi r. It consi sts of an 825-foot long embankment dike, wi th a crest elevation of 9517, and a 350-foot long rock-armored overflow section at elevation 9511 near the center. The dam has been repaired and modified several times over the years, most significantly in 1972 and 1973, when the crest elevation was lowered six feet, the service and auxiliary spillways added, and the outlet works repaired. Fi gure V. 2 in Section 2 of thi s chapter represents the exl sti ng dam and reservoir in plan and section. 1.2.2 Crest The crest of the dam is roughly 20 f'eet wi de and the servi ce road that runs along its length is well maintainect, with only minor vehicle rutting and irregularities in elevation. A widening of the dam crest to about 25 feet occurs just to the left of the main outlet works wet well. 1.2.3 Upstream Face The upstream face of the dam is generally in good condition. The slope is approximately 2.1H to 1V and is protected with hard angular riprap approximately 18 to 24 inches in di ameter deri ved from a quarry wi thi n the eastern limits of the reservoir and glacial erratics scattered throughout the reservoir. The riprap was added during the 1972 repairs and the drawings show it to be underlain by a blanket of impervious material. Debris on the upstream face is limited to an occasional piece of driftwood, with no vegetati ve growth. A berm has been constructed across the 1 ower part of the upstream face at approximately elevation 9490 to allow access across the creek. It appears to consi st of sandy gravel fill material covering the riprap and does not significantly affect slope stability. 1.2.4 Downstream Face The downstream slope of the dam is uniform at 3H to lV. from erosion by sandy gravel with cobbles to six inches, It has been protected and seeded. However, ~37-