National Program for Inspection of Non-Federal Dams. Lake Winnemaug Dam (CT 00123), Naugatuck River Basin, Watertown, Connecticut. Phase I Inspection Report.
CORPS OF ENGINEERS WALTHAM MA NEW ENGLAND DIV
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Lake Winnemaug Dam is an earth embankment approximately 500 feet long with a maximum height of about 15 feet. The upstream slope of the embankment is approximately 1H1V and the downstream slope is about 1.5H1V. The top of the dam is about 20 feet wide and it is a paved road. The overflow drop spillway is located about 100 feet from the right abutment and consists of an 18.5-foot long concrete weir, a cascading step section and a 4-foot high by 10-foot wide culvert through the embankment. The original purpose of the dam is unknown however, the lake is currently used for recreation purposes. The peak test flood inflow for Lake Winnemaug Dam is 3,460 cfs. The routed test flood outflow of 2,010 cfs overtops the dam by about 0.8 feet. The spillway is capable of discharging 770 cfs or about 38 percent of the routed test flood outflow prior to overtopping of the dam. A breach of the dam would result in a 7.8-foot increase in the stream depth 3.8 feet above the channel banks at the initial downstream damage area. The dam appears to be in poor condition. Numerous structural deficiencies, such as slope failures, seepage, and toe erosion were observed during the visual inspection. The embankment is overgrown with brush and trees and contains a number of rodent holes. The reservoir cannot be drained in an emergency because the outlet pipe control valve is inoperable.
- Hydrology, Limnology and Potamology
- Civil Engineering