Monitoring work will start Monday on the Union Street Dam in downtown Traverse City, according to a city release.

The city is contracting with engineering consultant AECOM to complete the work. According to City Director of Public Services Frank Dituri, because of pending litigation in the Michigan Court of Appeals, the planned $19.3 million reconstruction of the dam as part of the FishPass project “is experiencing delays that are beyond the city’s control and at this time have no determinable length.” Dituri previously noted that a recent state inspection of the dam “downgraded the rating of the dam to fair-to-poor condition,” and that “to continue to maintain public safety it is necessary to secure engineering consultant services to monitor the condition of the dam.”

AECOM will be completing work at the Union Street Dam site including:

> Establishing a topographic survey and survey monuments on the dam
> Investigating slope stability and seepage and monitor piezometer levels
> Evaluating spillway capacity
> Evaluating and planning for tree removal
> Monitoring and developing sheet pile gap closure
> Monitoring and plan for repair of concrete surfaces
> Inspecting submerged portions of the dam through dive/video inspections
> Updating the project operations and maintenance plan
> Conducting quarterly inspections of the dam and project structures, including survey of monuments

Initial work will require surveyors and engineers to be on-site to measure, document, and photograph the site. Additional work will set reference monuments with hand tools on existing structures. The geotechnical "slope stability" component of this work will require a drilling equipment truck and vehicles on-site to facilitate the installation of water level monitoring devices. Future monitoring will include specially trained divers, who will conduct an underwater dive to inspect subsurface components of the dam. The monitoring work will enable reproducible measurements which when compared can indicate any change or movement in the conditions of the dam.