Kent Lake Dam Repairs

Kent Lake Dam is an earthen dam in New Kent County, Virginia, owned by the Woodhaven Property Owners Association, topped by a road and having a total head of 24 feet. It was constructed in the early 1960’s. The emergency spillway is on the northwest portion of the dam and is a lowered section of the crest of the dam armored on the upstream side by rip-rap and on the downstream side a concrete apron. A sluice gate, supported by a metal frame and structure, is located near the upstream toe of the dam to allow the water to be lowered. The gate is attached to a corrugated metal pipe outfall sluice approximately 153 feet in length traversing the dam and opening into a wetland, the continuation of Toe Ink Creek on the downstream side. We were first contacted due to a high velocity leak through the outfall despite their best efforts to close the gate. Inspection by diver and submersible video camera showed a rotational failure from the right wedge, with water entering in a crescent from where the valve had been displaced. The corrugated metal pipe was in poor, deteriorated condition, and had been displaced at the joint nearest the downstream, creating a sinkhole that had been filled with brush and debris. The inspection had established the need for slip-lining, but draining the lake during this drought year was not tolerable to the owner. A method for slip-lining without lowering the pool was devised. 5 pp., 6 figures.