The DeRuyter Reservoir Dam is owned by the State of New York under the jurisdiction of the NYSCC. The DeRuyter Dam is located at the north end of the DeRuyter Reservoir at the border of Madison and Onondaga County, New York. This dam is classified by the NYSDEC as a large, Class C, High Hazard dam. Bergmann Associates and McMahon & Mann teamed to complete a dam safety inspection and engineering assessment for the dam in 2012, as required by NYCRR Part 673.16.
The DeRuyter Reservoir Dam is owned by the State of New York under the jurisdiction of the NYSCC. The DeRuyter Dam is located at the north end of the DeRuyter Reservoir at the border of Madison and Onondaga County, New York. This dam is classified by the NYSDEC as a large, Class C, High Hazard dam. Bergmann Associates and McMahon & Mann teamed to complete a dam safety inspection and engineering assessment for the dam in 2012, as required by NYCRR Part 673.16.
DeRuyter Dam was originally constructed in the years 1861-63. The dam’s original construction is an embankment of random, largely silty, fill. Prior to rehabilitation in the 1950’s, seepage including some piping and slope failures occurred at the dam. In the early 1950’s, a major rehabilitation and stabilization effort was undertaken. The rehabilitation included installing an internal drainage system and constructing an earthen buttress against much of the downstream embankment slope. Maintenance work on the drainage system was completed in the late 1980’s.
After seepage, slope stability, and hydraulic deficiencies were identified in the engineering assessment, rehabilitation design efforts were made between 2014 and 2018. The designed improvements included installing seepage control blankets and buttresses on the downstream slope, reconstructing a majority of the primary spillway, decommissioning the low-level outlet and replacing it with a siphon pipe system through the existing embankment, reconstructing the roadway crest, and installing seepage measurement devices at each of the seepage collection discharge points.
Construction occurred in 2019 and 2020, with McMahon & Mann observing geotechnical construction activities on a part-time basis. This monitoring included a stability evaluation of the western buttress construction and embankment fill was placed over a soft clay deposit beneath the site. This included regular monitoring of the piezometers and an inclinometer at the site. McMahon & Mann coordinated with Bergmann and NYSCC representatives to review construction activities and changes in conditions related to the earthwork aspect of the project.
