City Home > News

Monitoring Services of the Union Street Dam to Begin

by Colleen Paveglio
Friday, November 19, 2021

Contracted Consultant Monitoring Services of the Union Street Dam to Begin  

Monitoring necessary due to a recent MDEQ downgrade of dam condition

Update: Mobilization for sampling and monitoring will begin on Monday, November 29th. A drill rig and and additional equipment will be onsite to perform the work.

The pedestrian route across the bridge on the dam will be obstructed for 5-7 days while the equipment is onsite and work is being performed. Pedestrians should utilize the Union Street Bridge as an alternative route.


Beginning Monday, November 22, 2021, the City of Traverse City will have monitoring services conducted of the Union Street Dam.  A required MDEQ Dam Safety Unit inspection was recently performed and indicated a downgraded rating from Good to Fair/Poor condition. The Michigan Dam Safety Unit inspected the Union Street Dam on May 27, 2021 and recommended several maintenance activities and investigatory tasks in their June 18, 2021 inspection report.

The City of Traverse City has been permitted through a Joint Permit Application process with the USACOE and MDEQ for the replacement of the Union Street Dam. Due to unexpected delays, because of the litigation against the city in connection with the FishPass Project, the City has contracted with AECOM to perform monitoring services at the Union Street Dam. The scope of work is as follows;


  • 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 two (4) quarterly inspections of the dam and project structures; including survey of monuments

“While the planned FishPass Project is on hold, to continue to maintain public safety, it is necessary to provide services to monitor the condition of the Union Street Dam,” says City Manager Marty Colburn

Initial work will include surveyors and engineers onsite 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.