National Program for Inspection of Non-Federal Dams. Grupes Reservoir Dam (CT 00057), Connecticut Coastal Basin, New Canaan, Connecticut. Phase I Inspection Report.
CORPS OF ENGINEERS WALTHAM MA NEW ENGLAND DIV
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The dam, built in 1871, is a 225 foot long stone and mortar masonry gravity dam used for water supply. There are two spillways a main spillway section at the left end of the dam and an auxiliary spillway approximately 40 feet upstream from the right end of the dam. The two outlets are 24 inch and 16 inch cast iron pipes. The 24 inch pipe is located at the left end of the dam and serves as a low-level outlet or a supply line. The 16 inch pipe is located at the right end of the dam and is used as an emergency supply line. Based upon the visual inspection at the site and past performance, the dam is judged to be in fair condition. The masonry of the dam and training walls appears to be in fair condition. There are areas requiring maintenance and monitoring such as cracks in the mortar joints of the masonry in the dam and spillway walls and seepage at the right end and central portion of the dam. The spillway capacity with the reservoir level to the top of the dam is 2900 cfs, which is equivalent to 18 of the PMF outflow. The spillway capacity does not include flow over the low area in the service road.
- Hydrology, Limnology and Potamology
- Civil Engineering