This dam has been classified as unsafe, non-emergency by the St. Louis District as a result of the application of the following criteria: the combined capacity of the spillways will not pass 50 percent of the Probable Maximum Flood without overtopping the dam; overtopping of the dam could result in failure of the dam; and dam failure significantly increases the hazard to loss of life downstream.

Lynch Lake Dam was inspected. Based on the criteria in the guidelines, the dam is in the high hazard potential classification, which means that loss of life and appreciable property loss could occur in the event of failure of the dam. The estimated damage zone extends approximately three miles downstream of the dam. Within the first two miles of the damage zone are nine dwellings, Highway NN and bridge which may be subjected to flooding, with possible damage and/or destruction, and possible loss of life. Lynch Lake Dam is in the small size classification since it is less than 40 feet high and impounds less than 1,000 acre-feet of water.

This report was prepared under the National Program of Inspection of Non-Federal Dams. This report assesses the general condition of the dam with respect to safety, based on available data and on visual inspection, to determine if the dam poses hazards to human life or property. (Author).

Lake Serene Dam is an earthfill structure approximately 37 ft high and 1200 ft long at the crest. The appurtenant works consist of a rock cut spillway with a concrete weir control structure located at the south abutment, and a 12-in. diameter siphon pipe located near the north end of the dam. Our inspection and evaluation indicates that the spillway does not meet the criteria set forth in the guidelines for a dam having the above size and hazard potential. The spillway will pass 27 percent of the Probable Maximum Flood without overtopping. Deficiencies visually observed by the inspection team were: (1) erosion at the contacts of the dam with the north and south abutments; (2) tree and brush growth on downstream face of dam; (3) animal burrows on face of dam; (4) concrete debris on dam face near spillway; and (5) debris in spillway outlet channel.

This report assesses the general condition of the dam with respect to safety, based on available data and on visual inspection, to determine if the dam poses hazards to human life or property. The inspection team concluded that the dam is unsafe. Based on the criteria in the guidelines, the dam is in the high hazard potential classification, which means that loss of life or appreciable property loss could occur in the event of failure of the dam. A subdivided recreational development with several dozen numbered lots is located adjacent to the creek within a mile below the dam. These lots are apparently in frequent use for camping. Several downstream residences would also be subject to possible damage. The dam is in the intermediate size classification since it is more than 40 feet high. A major earth slide was present on the downstream face. Excessive seepage was occurring through and beneath the dam and its abutments. The spillway in the right abutment is inadequate to pass any flow without overtopping, because the invert of the spillway is higher than the top of the dam.

This report was prepared under the National Program of Inspection of Non-Federal Dams. This report assesses the general condition of the dam with respect to safety, based on available data and on visual inspection, to determine if the dam poses hazards to human life or property. (Author).