National Dam Inspection Program. Spruce Reservoir Dam (NDI I.D. PA-487, DER I.D. 60-7) Susquehanna River Basin, Spruce Run, Union County, Pennsylvania. Phase I Inspection Report.
Abstract
Based on the evaluation of the existing conditions, the condition of Spruce Reservoir is considered to be fair. In view of indications of surficial slumps on the downstream face of the main embankment, combined with the observations that the embankment does not have any internal drainage system to control seepage through the embankment and the downstream slope is relatively steep (2H:1V), concern exists as to the actual location of the phreatic surface through the embankment and its effect on the stability of the dam. Based on these observations, reevaluation of the stability of the embankment is recommended. According to the recommended criteria, intermediate size dams in the high hazard category are required to pass full probable maximum flood (PMF) without overtopping the embankment. The flood discharge capacity was evaluated according to the recommended criteria and the bypass channel spillway was found to pass 60% of the PMF without overtopping the embankment on the upstream side of Spruce Reservoir. For 80% of the PMF, it was found that flow entering the reservoir over the upstream embankment can pass through the reservoir overflow spillway without overtopping the main embankment.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1980
- Accession Number
- ADA091164