National Dam Inspection Program. St. Mary's River Watershed, Site Number 1, (NDI-ID Number MD-28) Potomac River Basin, Western Branch of St. Mary's River, St. Mary's County, Maryland. Phase I Inspection Report

摘要

St. Mary's River Watershed, Site No. 1, completed in 1975, is a zoned earth fill embankment with an impervious core, a cutoff trench, and a toe drain. The embankment is 38 feet high at its maximum section and is approximately 1670 feet long. The flood discharge facilities for the dam consist of the principal spillway comprised of a drop inlet spillway and two manually operated sluice gates located in the spillway riser structure, and a 300 foot wide emergency spillway located adjacent to the right abutment of the dam. According to the hydrologic and hydraulic analyses, the St. Mary's River Watershed, Site No. 1 dam will pass 100 percent of the Probable Maximum Flood without overtopping, and therefore its spillway is rated adequate.