National Dam Inspection Program. Ligonier Dam (NDI Number PA-00477, PennDER Number 65-117), Ohio River Basin, South Fort of Mill Creek, Westmoreland County, Pennsylvania. Phase I Inspection Report,
Abstract
Ligonier Dam (Ligonier Township Reservoir) is classified as a 'High' hazard - 'Small' size dam. The dam and reservoir, owned by the Ligonier Township Municipal Water Authority, are used for water supply. The dam was found to be in good overall condition at the time of inspection. Hydraulic/hydrologic evaluations, performed in accordance with procedures established by the Baltimore District, Corps of Engineers, for Phase I Inspection Reports, revealed that the spillway will pass approximately 35 percent of the Probable Maximum Flood (PMF) before overtopping will occur. A spillway design flood (SDF) in the range of the 1/2 Probable Maximum Flood (1/2 PMF) to the PMF is required for Ligonier Dam. Because of the relative small size of the impoundment the 1/2 PMF was chosen as the SDF. It was determined that during the 1/2 PMF the low area on the embankment would be overtopped by a depth of 0.66 foot and a duration of 4.50 hours. Because a limiting criteria of one foot or greater depth of overtopping and a duration of 2 hours was estimated for this dam, it was concluded that a dam failure during the 1/2 PMF is unlikely to occur.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 1980
- Accession Number
- ADA085236
Entities
People
- John A. Dziubek