National Dam Safety Program. Ephratah Dam (Inventory Number NY 178), Mohawk River Basin, Fulton County, New York. Phase I Inspection Report,
Abstract
The Ephratah Dam is 760 feet long, buttressed concrete and cyclopean masonry dam containing an ogee spillway, 3 arched sections, a concrete gravity section and an earth embankment section. The maximum height of the dam is 65 feet. The ogee spillway is 251 feet long and has a crest elevation of 974.15. A 3 feet diameter reservoir drain is located at the base of the middle arched section. The flow of the drain is controlled by a manually operated butterfly valve located in the building at the toe of the dam. The power generation intake system is located on the upstream face of the south abutment. A 6.5 feet diameter wood stave pipe carries water from the intake 2 miles to the power plant. All regulating outlets are operational. The concrete portions of the dam exhibit signs of major deterioration as indicated by the extensive seepage which appears on the downstream face. Gunite and epoxy injection treatments have failed to control the flow. The discharge capacity of the spillway is inadequate for all flow in excess of 17% of the Probable Maximum Flood (PMF). The spillway is not considered seriously inadequate, based on the Corps of Engineer's Screening Criteria, since the dam is a gravity structure and the stability analyses indicate that the dam is not unstable during a PMF event.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 17, 1979
- Accession Number
- ADA078042
Entities
People
- George W. Koch
Organizations
- New York State Department of Environmental Conservation