National Program for Inspection of Non-Federal Dams. Bevins Pond Dam (CT 00360), Connecticut River Basin, East Hampton, Connecticut. Phase I Inspection Report

摘要

The dam, completed in 1898, is an earth embankment with a total length of approximately 500 feet, including a 21.6 foot wide masonry rectangular weir spillway near the center of the dam. Above the spillway crest, permanent stop planks backfilled with gravel raise the pond level 1.6 feet. With the pond level to the top of the dam, the dam impounds approximately 240 acre-feet of water. At the right abutment of the dam is an abandoned grass emergency spillway which is blocked by an earth berm. A 24 inch low-level outlet passes through the embankment to outlet at the toe of the spillway wall and is operated from the gatehouse adjacent to the spillway. From the left gatehouse a 36 inch penstock passes through the embankment to the factory building as a supply line for a water wheel. Based upon the visual inspection at the site and past performance, the project is judged to be in fair condition. However, there are items which require maintenance and/or evaluation, such as irregularities and protection of the upstream and downstream embankment slopes. Peak inflow to the reservoir at the full PMF is 3800 cubic feet per second (cfs); peak outflow is 3700 cfs with the dam overtopped by 2.5 feet. The spillway capacity with the reservoir level to the top of the dam is 250 cfs, which is equivalent to 6.8% of the routed test flood outflow.