National Program for Inspection of Non-Federal Dams. West Lake Reservoir Dam (CT 00070), Housatonic River Basin, Danbury, Connecticut. Phase I Inspection Report.
CORPS OF ENGINEERS WALTHAM MA NEW ENGLAND DIV
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The West Lake Reservoir Dam is an earth embankment that is approximately 450 feet long and 31.7 feet high. The embankment has 1.51 side slopes and has a puddled clay and gravel core. The spillway is located through the northern abutment of the dam and consists of a 120-foot long concrete weir. There are upper and lower gate houses for the control of 30-inch water main and a 24-inch blowoff that passes through the base of the dam. The valves for the operation of the water main and the blowoff are in the lower gate house and are inoperable. The drainage area is 3.3 square miles and the reservoir has 3,430 acre-feet of available storage. The assessment of dam is based on the visual inspection, past operational performance and hydraulichydrologic computations. The dam is judged to be in fair condition with several areas that require attention. These areas include seepage through the dam and along the toe, steepness of the embankment, vegetation on the embankments, along the toe of the dam and in the spillway channel and the nonoperating status of the blowoff. The dam is classified as intermediate and has a high hazard potential in accordance with guidelines established by the Corps of Engineers. The test flood for this dam is 12 the Probable Maximum Flood PMF. The test flood inflow is 6,520 cfs and the routed test flood outflow is 3,890 cfs. The test flood outflow will overtop the dam by 1.0 feet.
- Hydrology, Limnology and Potamology
- Civil Engineering