National Dam Inspection Program. Steel Dam (NDI I.D. Number PA-00495, PENNDER I.D. Number 63-63), Ohio River Basin, Center Branch of Pigeon Creek, Washington County, Pennsylvania

摘要

The visual inspection, operational history and hydrologic/hydraulic analysis indicate that the facility is in good condition. The size classification of the facility is small and its hazard classification is considered to be high. In accordance with the recommended guidelines, the Spillway Design Flood (SDF) of the facility ranges between the 1/2-PMF (Probable Maximum Flood) and the PMF. Due to the high potential for damage to downstream structures and possible loss of life, the SDF is considered to be the PMF. Results of the hydrologic and hydraulic analysis indicate the facility will pass and/or store approximately 51% of the PMF prior to embankment overtopping at the low top of dam. Thus, the spillway system is considered to be inadequate, but not seriously inadequate. Should the embankment crest be regraded to design elevation, the spillway would be capable of passing approximately 60% of the PMF prior to embankment overtopping.