US 31–Island Lake Outlet Bridge

The US 31-Island Lake Outlet Bridge is a bascule bridge with two steel leaves that each span 45 feet across the waterway connecting Lake Charlevoix to Lake Michigan. The structure lifts vertically to allow boat traffic to pass underneath while supporting highway traffic when closed.

The bridge opened in 1949 as a replacement for a swing truss structure that had operated since 1901. Wartime construction delays pushed back the completion of this newer bascule design.

The bridge serves as a working connection between communities on both shores, with residents and visitors routinely experiencing the coordinated rhythm of road and water traffic. This intersection of transportation modes shapes how people move through the area.

The bridge regularly opens for boats during the boating season from June through September, causing delays for vehicle traffic on US 31. Plan to cross at quieter times like early morning or evening to minimize waiting.

Each steel leaf contains a 73-ton concrete counterweight system that keeps the bridge balanced during raising and lowering. This mechanical design allows the heavy spans to operate smoothly without excessive engine power.

Location: Charlevoix

GPS coordinates: 45.31890,-85.25870

Latest update: December 14, 2025 11:24