National Program for Inspection of Non-Federal Dams. Sawmill Pond Dam (CT 00627), Thames River Basin, Voluntown, Connecticut. Phase I Inspection Report.

Sawmill Pond dam is a 180 foot long earth embankment including a 51.5 foot long spillway and 15.5 foot wide intake structure. The dam has a maximum height of 20 feet and an impoundment capacity of 40 acre-feet. The downstream face of the earth embankment is a vertical stone masonry wall and the upstream face has a slope of 21. A 15.5 foot wide headrace extends from the intake structure at the left abutment to about 100 feet downstream. The maximum spillway capacity is equal to 1,120 CFS which represents only 9 of the test flood outflow. It is recommended that the owner engage the services of a registered engineer experienced in the design of dams to accomplish the following 1 Perform detailed hydrologic and hydraulic studies to assess further the potential for overtopping the dam and the need for and means to increase the project discharge capacity 2 Inspect the downstream face of the principal spillway with no water flowing over it 3 Evaluate the seepage from the right embankment and the left side of the principal spillway 4 Evaluate the need for, and design as required, a low level outlet to control the pond level 5 Recommend and supervise the placement of riprap on the upstream face and abutments 6 Remove trees and their root systems from the dam to a distance of 15 feet downstream and backfill the holes with appropriate compacted soil.