Muskingum River Lock and Dam No. 7 Replacement

Muskingum Lock and Dam No. 7 (also known as McConnelsville Dam) is located on the Muskingum River in the Village of McConnelsville, in Morgan County, Ohio. The dam is a Class II structure that is owned and maintained by the Ohio Department of Natural Resources, Division of Parks and Watercraft. The existing dam is 65 years old and consists of multi staged dam with 24-foot diameter cellular sheet piles filled with sand and gravel and capped with concrete. Adjacent to the dam is Lock Number 7, which provides travel in the Muskingum River between other lock structures.  The current dam is in poor condition requires a complete replacement. The replacement dam is currently in final design stages with the construction anticipated to start in the summer of 2024.

The project encountered several engineering challenges including limited options for the replacement dam location, constructability concerns caused by the highly variable river conditions, and the limited access to the site.  After thorough evaluations, the team chose to design a stepped dam downstream of the current structure.  This unique approach differs from other dams along the Muskingum River and aims to effectively manage dissipation as water flows over the dam.  To minimize the impact on aquatic resources, the dam’s footprint was reduced through the incorporation of rock anchors for structural stabilization. The project is being delivered through a Construction Manager at Risk delivery method and marks one of the first dam replacements on the Muskingum River that is anticipated over the next several years.