CPKC Irving Park Road Bridge (Irving Park)

Located in the Irving Park neighborhood of Chicago, this through plate girder bridge carries the Metra Milwaukee District North line over Irving Park Road. During the late 19th Century, railroad traffic within the City of Chicago posed a serious hazard to the general population. Starting in the mid-1890s, the City of Chicago passed a number of ordinances mandating the elevation of tracks within the city. As a general rule, these ordinances required the railroad line to be elevated, and underpasses to be constructed at street crossings. An ordinance was passed on February 21st, 1898 requiring the elevation of the Mayfair Division of the Chicago & North Western Railway (C&NW) and the Chicago Division of the Chicago, Milwaukee & St. Paul Railway between Milwaukee Avenue and Irving Park Road. Contracts for the work were let in 1898, and the project would be completed in 1899. This section of track elevation required few retaining walls, and the elevation was mainly accomplished by lowering the streets.

The bridge carrying the Milwaukee Road over Irving Park Road consists of a three span through plate girder bridge, set onto concrete abutments and steel bent piers. The roadway span of the bridge is 64 feet in length, while the two sidewalk spans are each 24 feet in length. Typical of track elevation structures along this line, the bridge utilizes a deep taper on the ends of the girders, and the floor of the bridge is constructed of parallel floorbeams, covered by a sheet metal deck. Lassig Bridge & Iron Works fabricated the steel for the bridge, and railroad labor constructed the abutments of the bridge. This type of structure was initially popular for grade separations in Chicago, but fell out of favor as trough floor spans and concrete spans became more economical. The metal floor of this design of bridge was susceptible to pooling water, which would cause corrosion to the steel. In addition, the through girder design limited horizontal clearances on the bridge. Numerous repairs have been made on the bridge, including replacement of the bracing between the columns of the piers. Overall, the bridge appears to be in fair to poor condition, with deterioration noted throughout the structure. The author has ranked this bridge as being locally significant, due to the common design.