National Program for Inspection of Non-Federal Dams. Upper Pond Dam (CT 00433), Lower Connecticut River Basin, Haddam, Connecticut. Phase I Inspection Report.
Abstract
Upper Pond Dam is an earth embankment dam with a maximum height of 17 feet and a length of 390 feet. The dam embankment left of the spillway is approximately 10 feet in width, with 2 horizontal to 1 vertical upstream and downstream embankment slopes. The centrally located spillway is 72 feet in length and is a stone masonry structure. Stone masonry training walls approximately 5 feet in height are located at each side of the spillway. The outlet works consist of a concrete gate structure and an outlet channel. Based on the visual inspection, the Upper Pond Dam appears to be in poor condition. There was no movement or settlement of the crest observed. The horizontal alignment is good. The top of the outlet gate structure, however, is lower than the embankment crest. Some erosion was noted at the abutments, adjacent to the spillway section and adjacent to the outlet works. Trespassing on the slopes was not significant. Erosion scarps on the upstream slope extending 1-2 feet above waterline were noted. Several areas of broad shallow erosion on the upstream slope and upstream side of abutments were observed. Brush and many large trees (up to 2.5-ft.-dia.) with extensive root systems were noted on the slopes and crest of the dam. Standing water was observed in an area 35 feet downstream of the toe on the right side of the dam. The capacity of the spillway is inadequate to pass the 1/2 PMF test flood outflow of 5,195 CFS and would overtop the dam by about 0.9 feet. The spillway can pass about 33 percent of the test flood.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 1980
- Accession Number
- ADA144584
Entities
Organizations
- New England District, U.S. Army Corps of Engineers