The Natural Pier Bridge


Alberton 59820,Missoula Area,Mineral County

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Historical Markers/Interpretive SignHistoric Sites
General info

Location: I-90 Exit 75 just west of Alberton.

This structure is an example of how engineers incorporated a natural feature into the design of a bridge. Designed by Montana Highway Commission bridge engineers, the bridge is a standard riveted Warren through truss. The bridge is unusual in that one of the piers is anchored to a rocky outcrop in the Clark Fork River. The bridge was once a component of the Yellowstone Trail—which traversed Montana from Lookout Pass to North Dakota.

Responding to pressure from the lumber companies and the Yellowstone Trail Association, Mineral County embarked on an ambitious bridge-building program in 1916. Although the county was responsible for the construction of the bridge, fiscal limitations and its location near the Lolo National Forest forced the county commissioners to seek financial aid from the federal government. In early 1917, the county contracted with the Wisconsin-based Wausau Iron Works Company to build the bridge. Work progressed steadily on the bridge for several months when the county ran out of money for its construction. After securing additional federal funds, the county commissioners called a referendum to raise money to

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