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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 />The concrete service spillway is in poor condition. Several small cracks were <br />observed in the crest, chute, and apron sidewall s. Seepage emerges through <br />cracks in the lower portion of the chute and the apron sidewalls. Standing <br />seepage water and debris obscured the apron floor slab. <br /> <br />The auxi 1 i ary spi 11 way is in very poor conditi on, and if it were requi red to <br />operate, woul d probably fail due to: 1) inadequate protecti on of the <br />relatively steep 2H to lV downstream slope; 2) the lack of filtering and <br />bedding between the earthfill and slope protection; and 3) the high potential <br />for erosion of the earthfill beneath the riprap. The probability of the <br />auxiliary spillway operating, if full storage were allowed in the reservoir, <br />is high because of crest undulations along the dikes. Surveying performed <br />during the site inspection indicated that in many places the dike crest is <br />less than 0.5 feet above the service spillway crest, and in one location, <br />level with it. <br /> <br />The riprap protection at the emergency spillway is adequate and the structure <br />appeared to be in good condi ti on. However, the contai nment berm on the 1 eft <br />side of the converging discharge channel appears to be insufficient in height <br />and length to protect the downstream toe of the dam from possible erosion <br />duri ng spi 11 i ng. If overtoppi ng of the emergency spi 11 way were to occur, <br />flows would endanger the main access road, private cabins, and safety of the <br />dam. This deficiency has been noted in several inspection reports prepared by <br />the SEO. <br /> <br />Field inspection and surveying showed that a portion of the man-made dike <br />forming the left side of the Chambers Lake inlet channel would actually <br />function as an embankment dam if full storage were allowed in Barnes Meadow <br />Reservoir, and especially during the routing of a major flood event. This <br />di ke does not meet any of the SEO' s requi rements for embankment dams. The <br />crest is too narrow, the slopes oversteepened, dense vegetation is present, <br />and numerous animal burrows exist. <br /> <br />A geotechni cal i nvesti gati on was conducted in the fi el d and 1 aboratory to <br />evaluate the materials that comprise the dam, foundation, and reservoir. The <br /> <br />E-4 <br /> <br />l15lc <br />