National Dam Safety Program. Cole Lake Dam, No Name 249 (MO 30430), Mississippi - Kaskaskia - St. Louis Basin, Jefferson County, Missouri. Phase I Inspection Report

Download or read book National Dam Safety Program. Cole Lake Dam, No Name 249 (MO 30430), Mississippi - Kaskaskia - St. Louis Basin, Jefferson County, Missouri. Phase I Inspection Report written by Henry M. Reitz and published by . This book was released on 1978 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt: No-Name 249 Dam was inspected by an interdisciplinary team of engineers. The purpose of the inspection was to make an assessment of the general condition of the dam with respect to safety, based upon available data and visual inspection, in order to determine if the dam poses hazards to human life or property. Failure would threaten the life and property of four families and cause appreciable damage to associated buildings and one county road to the junction with an east-trending branch (3 miles) and 10 more families within one mile below the junction. Our inspection and evaluation indicates that the dam is deficient in that the spillway does not meet the criteria set forth in the guidelines for a dam having the above size and hazard potential. Considering the potential volume of water impounded, the narrow floodplain and the four groups of buildings downstream, and the potential for future development in or near the floodplain downstream, the Probable Maximum Flood (PMF) is the appropriate spillway design flood. The Probable Maximum Flood is defined as the flood discharge that may be expected from the most severe combination of critical meteorological and hydrologic conditions reasonably possible in the region. The dam will begin to be overtopped by a flood having a discharge (peak and volume) equal to 30% of the PMF. The spillway will pass a 1% chance flood (100-year flood) without overtopping which is a flood that has a 1% chance of being exceeded in any given year.