Traverse County Bridge, County Road 76 SAP 078-598-037

In cooperation with the Minnesota State Aid, Region 4, Traverse County replaced an existing bridge with a 100-foot, 3-span bridge over the Mustinka River on Traverse County Road 76 during the 2019 construction season.

The old bridge was built in 1954 and classified as structurally deficient, with a sufficiency rating of 41.0. The existing center span superstructure consists of steel beams topped with a treated timber deck, and the approach end spans consist of deteriorated timber beams and a timber deck.

The bridge’s roadway width was 24.2 feet, totaling 97.89 feet. Due to its deteriorated condition, it was posted for 11-17-17 vehicle maximum loads.

Interstate Engineering analyzed the existing structure and proposed three replacement alternative structures with USACE HEC-RAS hydraulic modeling. Traverse County ultimately selected to proceed with the final design of a 130-foot, 3-span continuous concrete bridge having a 32-foot bridge opening. Interstate Engineering completed the bridge design per MnDOT criteria.