Discover the 4 Longest Bridges in Montana

Lake Koocanusa Bridge

The Lake Koocanusa Bridge is the longest and tallest bridge in Montana. The bridge goes across the entire Lake Koocanusa, and it’s 2,437 feet long. This specific bridge is 270 feet above the water. However, it can vary based on the lake’s depth. Lake Koocanusa Bridge connects Montana’s Highway 37 with the reservoir’s western side.

This bridge was constructed in the early 1970s by the Army Corps of Engineers. The purpose of the bridge was so that people who lived on the western side of the lake could get to the eastern side quicker than driving around the entire lake. Due to its length, the bridge requires six truss spans on five piers. Both sides of the bridge are also tied into some bedrock. Lake Koocanusa Bridge won the American Institute of Steel Construction award for the “Most Beautiful Bridge” in 1972.

Before the bridge was built, the western Montana citizens had issues getting around a new Libby Dam built on the Kootenai River. The dam provides hydroelectric power and flood protection within the area.

Yellowstone River Bridge

The Yellowstone River Bridge underwent recent reconstruction. This 1,142-foot-long bridge goes across the Yellowstone River and has some issues due to wear and tear. It began this decade, and some of its construction involved fixing chip damage, roadway striping, chip sealing, and two vehicular lanes going in each direction. There will also be a 10-foot shared path on the west side of the bridge to connect the Dover Park Trails. Its anticipated opening will occur in 2024 as soon as the Railroad Overpass project segment is completed.

The bridge was first constructed in 1902 but was known as a famous fishing bridge in 1914. In 1919, the bridge was reconstructed to have walkways on each side of the roadway across the bridge. There were several additions to the bridge, such as a boathouse and further renovations for structural purposes.

Tenth Street Bridge

The Tenth Street Bridge is a Great Falls bridge across the Missouri River. Montana natives and historians alike recently celebrated its 100th anniversary back in 2020. The need for the 1,275-foot-long bridge came about in 1918. It connected the Black Eagle community, outlying rural towns, and farms to the town proper. The Tenth Street Bridge served Montana citizens until the mid-90s when the Ninth Street Bridge was built. There were plans to demolish the Tenth Street Bridge because it wasn’t being used as much as the Ninth Street Bridge. However, a group of activists helped to divert the demolition. The bridge began being used as a pedestrian bridge along with other purposes to connect the Great Falls and the Black Eagle communities.

Lewis And Clark Bridge

The Lewis and Clark Bridge is 1,074 feet long. It helps connect the former Montana Highway 13 at Wolf Point. It is a Pennsylvania through truss bridge that was completed in 1930. The Lewis and Clark Bridge is still one of the oldest truss bridges in the United States. Also, it is one of the longest truss bridges in Montana. When completed, it provided access to the Great Northern Railway station at Wolf Point for isolated farmers and rural citizens on the south side of the Missouri River. The bridge’s opening drew in over 10,000 visitors and five bands and finished with a fireworks display. This Lewis and Clark Bridge was registered in the Nationa Register of Historic Places in 1997. The bridge spans the McCone and Roosevelt Counties.