National Dam Inspection Program. Union Pond Dam (CT 00013), Upper Connecticut River Basin, Hockanum, Manchester, Hartford County, Connecticut. Phase I Inspection Report.
CORPS OF ENGINEERS WALTHAM MA NEW ENGLAND DIV
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The dam is a concrete gravity structure with the spillway constructed in an L shape. The total length of the dam is approximately 590 feet including the earth dike. The top of the dam is approximately 33 feet above the bed of the Hockanum River. The spillway is a broad crested compound weir of trapesoidal cross-section consisting of an outer concrete shell over an inner earth and rubble core. In 1972 No. 8 reinforcing bars grouted into 2 inch diameter holes 20 feet long and spaced at 10 foot intervals were installed through the top of the old dam, probably in an attempt to stabilize the upper portion of the present dam. The spillway crest is four feet below the top of the dam abutments. There are four outlets from the dam. Based upon the visual inspection and its past performance, the dam appears to be in poor condition. The stability of the structure appears to be marginal based on existing data, and the downstream concrete facing of the spillway is heavily deteriorated. The condition of the dike appears good, however the gatehouse adjacent to the dike and dam, is partially demolished. The condition of the 9 foot conduit and the gate controlling it are questionable and warrant attention. There are other minor areas requiring attention as well. Based upon our hydraulics computations, the spillway capacity is 8400 cubic feet per second cfs, which is equivalent to 28 of the Test Flood.
- Hydrology, Limnology and Potamology
- Civil Engineering