National Program for Inspection of Non-Federal Dams, Gorton Pond Dam (CT 00157), Connecticut Coastal Basin, East Lyme, Connecticut. Phase I Inspection Report

摘要

The dam at Gorton Pond is an earth embankment with the crest approximately 225 feet in length including a spillway length of 62 feet. The dam consists of a 120 foot long main embankment, an overflow spillway and a 1-2 foot high earthen berm to the right of the spillway. The main embankment has a riprap crest and a downstream rock shell to a 1 1/2:1 slope. This section was reportedly designed to withstand occasional overtopping during high flows, however, no design data was found in the available files to substantiate this. The maximum height of the dam is 10 feet. The spillway is an uncontrolled concrete ogee weir and is located about 43 feet from the right dam abutment. The outlet works consists of a sluice gate controlled 36 inch square outlet and is located near the center of the embankment section. The sluice gate is manually operated. The dam has a storage capacity of 450 Ac-Ft at the spillway elevation of 27.0 NGVD and the reservoir and dam are used for recreation. The maximum spillway capacity is equal to 450 CFS which represents only 11% of the test flood outflow, therefore, the spillway capacity is considered inadequate.