National Dam Safety Program. Gudaitis Lake Dam (MO 30702), Mississippi - Kaskaskia - St. Louis Basin, Washington County, Missouri. Phase I Inspection Report

摘要

Gudaitis Lake Dam is in the small size classification based on its maximum height of 25 ft and on its reservoir storage volume of about 180 ac-ft. The small dam classification includes dams between 25 and 40 ft in height or having storage capacities between 50 and 1000 ac-ft. The inspection and evaluation indicate the dam is in fair condition. This evaluation is primarily based on hydrologic analyses that indicate that a flood greater than 12 percent of the PMF will effectively overtop the dam. The dam will also be effectively overtopped by the one percent probability-of-occurrence (100 year) flood event. A 40 ft wide zone of slow seepage was noted at the toe of the dam, but the seepage water was not transporting any soil particles at the time of our inspection. The downstream face of the dam is heavily vegetated with relatively young trees up to 12 in. in diameter. This vegetation obscured portions of the dam from inspection. The spillway discharge channel is narrow and shallow and is bordered by many large trees. Deep gulley erosion is occurring where this channel traverses steeper slopes. Flood flows in this channel could cause overtopping of the channel and erosion of the channel walls, resulting in possible erosion at the toe of the dam.