National Dam Inspection Program. Crystal Dam,(NDS ID Number PA-00677, DER ID Number 54-15). Municipal Authority of the Township of Blythe. Delaware River Basin, West Branch Schuylkill River, Schuylkill County, Pennsylvania. Phase I Inspection Report.

摘要

Based on the visual inspection, available records, calculations and past operational performance, Crystal Dam is judged to be in good condition. However, the spillway will not pass the Probable Maximum Flood (PMF) or one-half of the PMF without overtopping. If Crystal Dam should fail due to overtopping, the hazard to loss of life downstream from the dam would be significantly increased from that which would exist just prior to overtopping. Based on criteria established for these studies by the Department of the Army, Office of the Chief of Engineers (OCE), the spillway capacity is rated as seriously inadequate. The existing spillway can accommodate a flood with a peak inflow of 37 percent of the PMF peak flow. If the low areas of the top of the embankment were brought up to design grade, the spillway could accommodate a flood with a peak inflow of 61 percent of the PMF peak inflow. The spillway would then be rated as inadequate instead of seriously inadequate.