New weight restrictions are in place for heavy vehicle and commercial truck operators on Traverse City's North Union Street Bridge due to corrosion on some of the bridge's steel beams. The city hopes to repair the bridge in the near future and is working to line up funding for the project.

According to the city's Bay Brief, a "recent special inspection of the bridge found corrosion that limits the load capacity of some of the steel beams. Using the findings of the inspection a load rating analysis was conducted, confirming that the bridge must be posted with weight restrictions. The weight limits are intended to prevent loads that cause stresses in the affected beams above the safe limit from crossing the bridge."

The weight restrictions will be posted by truck type using a standard sign type at both ends of the bridge as well as ahead of the bridge starting this month. The weight restrictions are as follows:

1-unit truck (e.g., concrete truck) – Maximum allowable weight: 31 tons
2-unit truck (e.g., semi-trailer truck) – Maximum allowable weight: 32 tons
3-unit truck (e.g., semi-trailer truck with an additional trailer) – Maximum allowable weight: 41 tons

The restrictions are in place to prevent damage to the load-restricted beams until repairs can be completed. For reference, a 2023 Subaru Outback base model reportedly weighs 1.8 tons and a 2024 Cadillac Escalade reportedly weighs 2.9 tons. One ton is 2,000 pounds.

The city has already repaired six of its seven vehicle bridges since 2021, including the  South Cass Street Bridge, the Eighth Street Bridge, the Park Street Bridge, the West Front Street Bridge (complete new bridge), the South Union Street Bridge, and the North Cass Street Bridge. Approximately $13.3 million was invested in bridge projects between 2021 and 2023. The city has North Union Street Bridge repairs listed in its capital improvement plan for fiscal year 2025-26 and is working to secure project funding.

Photo credit: City of Traverse City