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I I I I I I I I I I I I I I I I I I I Riprap protection of the emergency spillway crest appeared to be adequate in size to provide overflow erosion protection. However, the containment berm on the left side of the converging channel appeared to be insufficient in height and length to protect the downstream toe of the dam from possible erosion duri ng spi 11 i ng. If overtoppi ng of the emergency spi 11 way were to occur, flows would endanger the main access road, private cabins, and safety of the dam. This deficiency has been noted in several inspection reports prepared by the SEO. 1.7 Chambers Lake Inlet Channel Field inspection and surveying revealed that a portion of the man-made dike of the Chambers Lake i n1 et channel woul d actually functi on as an embankment dam if full storage were allowed in Barnes Meadow Reservoir, and especially during the routing of a major flood event. This dike does not meet any of the SEO's requirements for embankment dams. The crest is too narrow, the slopes oversteepened, dense vegetation is present, and numerous animal burrows exist. It is MKE's opinion that the dike should be reconstructed over the length that would serve as a reservoir retention structure. 1.8 Summary of Deficiencies This section summarizes the technical deficiencies at Barnes Meadow Dam, as noted during the site inspection and review of project records. The deficiencies are listed in order of potential impact on the safety of the exi sti ng reservoi r. Thi s pri oriti zed 1 i st was used to 1 end focus to the geotechnical evaluation and hydrologic analysis, and served as a guide for the development of rehabilitation alternatives. o Uncertainties associated with overtopping of the emergency spi 11 way. o Poor condition of the outlet works conduit. o Inadequate ri prap protecti on and 1 ack of beddi ng between the earthfi11 and riprap on the auxiliary spillway dikes. 1231 H -45-