National Program for Inspection of Non-Federal Dams. Northfield School Upper Reservoir Dam (MA 00051), Connecticut River Basin, Northfield, Massachusetts. Phase I Inspection Report.
Abstract
Northfield School Upper Reservoir Dam is a 45-year old earth embankment dam which impounds water for the Northfield - Mt. Hermon School and the Town of East Northfield. The dam is approximately 240 feet long and has a maximum height of about 37 feet. A gatehouse located on the top of the dam provides access to outlet works for the dam. The dam appears to be in fair condition. No obvious signs of settlement or misalignment are evident; however, clear seepage and erosion are apparent at each of the abutments and at the toe of the dam. Lack of a comprehensive operation and maintenance program is also apparent, as evidenced by the presence of small trees and brush on the dam and large trees in close proximity to the dam. In addition, only one of the outlet valves was found to be operable. (Since the date of inspection, the Owner has notified us that all of the valves have been made operable.) The test flood peak inflow to Northfield School Upper Reservoir Dam was computed to be approximately 550 cfs. The corresponding outflow was also 550 cfs and resulted in a 0.5 foot depth of flow over the dam. The spillway (with the flashboards in place) has a discharge capacity of about 180 cfs, or roughly 33 percent of the routed test flood outflow, assuming the reservoir pool is at the top of the dam. Assuming the flashboards are removed or fail prior to overtopping of the dam, the spillway capacity would then be approximately 790 cfs or about 44 percent in excess of the routed test flood outflow.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 1981
- Accession Number
- ADA145241
Entities
Organizations
- New England District, U.S. Army Corps of Engineers