The Minnesota/Wisconsin 243 bridge over the St. Croix River will close to traffic for about a year starting in mid-October so crews can remove the existing structure and build a new $25 million bridge in the same location.

The current bridge, at Osceola, Wis., was built in 1953. The new bridge, which will be a concrete beam structure with three bridge piers, will address aging infrastructure and drainage issues.

The bridge will feature a shared-use bicycle and pedestrian path on its north side. The project also includes a new pedestrian and bicycle path linking Osceola Landing to the Village of Osceola.

Earlier this month, specialized dive teams relocated 8,500 native freshwater mussels from the construction area to a site beyond the in-stream work area, transportation officials said. Some of the 33 mussel species that were moved are protected or endangered and provide ecological benefits, they said.

Crews from Lunda Construction will be bringing equipment and materials on site through the end of this month. They will then build a temporary access road across the water, which will be used to reach the work area over the next year. During this time, boats and other river traffic should follow buoys marking a safe route through the work zone.

Reducing the length of the bridge closure was a project priority based on community feedback, transportation officials said. Lunda’s construction plan will allow the bridge to reopen sooner than originally planned, according to officials.

Weather and schedule permitting, the new bridge is expected to open in late 2027. Seasonal flooding, river water levels and other factors could impact the construction schedule, officials said.

During the bridge closure, motorists will be detoured to the U.S. 8 bridge at Taylors Falls and the Minnesota 36 bridge at Oak Park Heights. The travel time between the Osceola and Taylors Falls bridges is approximately 15 minutes, according to transportation officials. The travel time between the Osceola and Oak Park Heights bridges is approximately 30 minutes.