UP Marquette Avenue Bridge (South Milwaukee)

Located in South Milwaukee, this small through plate girder bridge carries the former Chicago & North Western Railway mainline over Marquette Avenue (Wisconsin Highway 32). It is unknown if there was a bridge at this location prior to 1897. In 1897, a new four track through plate girder span was constructed to cross the newly constructed Milwaukee, Racine & Kenosha Electric Railway. This bridge consisted of a typical through girder span, set onto stone abutments and fabricated by the American Bridge Works of Chicago, Illinois. In the late 1920s and early 1930s, the C&NW invested significant capital into this line, replacing lighter bridges with new heavier steel and concrete structures. In approximately 1930, the present structure was constructed to replace the 1897 bridge. One portion of the 1897 bridge was later reused at Bridge #C-25 across the Wolf River at Shawano, Wisconsin.. Currently, the bridge consists of a four track 45-foot through plate girder span, set onto stone abutments which have been encased with decorative concrete. The superstructure uses a shallow design, with shallow girders and a heavy floor system. An unknown contractor fabricated the superstructure, and an additional unknown contractor constructed the abutments. Through plate girder bridges were commonly used by railroads, as they were durable and easy to construct. Since the c. 1930 reconstruction, the only major alteration to the bridge came in approximately 2015, when the original stone abutments were covered with concrete. Currently, only one track of the bridge remains in use. Overall, the bridge appears to be in fair condition, with no significant deterioration noted. The author has ranked this bridge as being locally significant, due to the common design.