This four-span Pratt through truss rests on three stone piers in the river and concrete footings at each end. 712 feet in length, it would have been built before the turn of the century. The Northern Pacific Railroad pushed the line through the area in 1883, driving the final spike on September 8, 1883 near Independence Creek, MT.
If this bridge is original it would be at least 131 years old today.
One text, on page 677, in discussing archaeology of Chinese encampments which followed the construction of the railroad, mentions the
Perma Bridge encampment being first occupied in April of 1883. This suggests that this is, indeed, the original bridge, built in 1883.
Initially known as the Perma Bridge, after Perma, Montana, the chief engineer for this bridge was E.H. McHenry, while the engineer of bridges was K.E. Hilgard.
This bridge became part of the Burlington Northern Railway on March 2, 1970, with the merger of four railroads, the Great Northern Railway, Northern Pacific Railway, Spokane, Portland and Seattle Railway and the Chicago, Burlington and Quincy Railroad. Later, with another merger, the Burlington Northern became the Burlington Northern & Sante Fe (BNSF). It is now used by Montana Rail Link, which leases the line from the BNSF.
Coordinates are at a viewpoint by Highway 200.