UP Oak Creek Bridge (South Milwaukee)

Located in South Milwaukee, this large stone arch bridge carries the former Chicago & North Western Railway mainline over Oak Creek and Oak Creek Parkway. The first bridge at this location likely consisted of a timber pile trestle, constructed when the line was first built. In the late 1870s and early 1880s, the C&NW invested significant capital into this line, replacing timber bridges with iron and stone structures. In 1883, much of the trestle would be filled, and a two span stone arch bridge constructed in its place. Between 1890 and 1892, the C&NW double tracked much of this line. In 1890, the bridge was widened on the east end, giving the structure its present configuration. Currently, the bridge consists of two 32-foot stone arches, set onto stone substructures and constructed at a width of 43 feet. The superstructure uses a standard design, with two semicircular arches. The substructures also use a standard design, with stepped wing walls which extend diagonally from the bridge. An unknown contractor constructed the initial structure, and an additional unknown contractor constructed the east extension in 1890. Stone for the bridge consists of a white limestone, likely quarried at Duck Creek, Wisconsin. Since the 1890 construction, a number of alterations have been made to the bridge to help stabilize the structure. In 1951, a corrugated metal plate was added underneath the south arch, and the faces braced by a steel beam. The north arch was repaired in the same manner in 1955. Currently, only the west track remains in use. Overall, the bridge appears to be in fair to good condition, with no significant deterioration noted. The author has ranked this bridge as being moderately significant, due to the large size and age of the bridge.