CN Fox River Bridge (South Elgin)

Located near the former station of Coleman, this large deck truss bridge carries the former Illinois Central Railroad over the Fox River, Fox River Trail and the former Aurora, Elgin & Fox River Electric Company alongside Stearns Road. The first bridge at this location was constructed in 1887, when the line was built. This bridge consisted of six 88-foot riveted Warren deck truss spans, set onto stone substructures. The superstructure was fabricated by Union Bridge Company, which constructed many of the truss bridges for the Chicago, Madison & Northern Railroad. W.G. Darwin & Company constructed the stonework for the bridge. According to railroad records, an additional truss line would be added in 1931, and the outer trusses would be reconstructed in 1931, giving the structure its current configuration.

Currently, the bridge consists of six 88-foot, 10-panel riveted Warren deck truss spans, set onto the 1887 stone substructures. During construction of the current bridge, the tops of the substructures would receive a concrete cap to accommodate the new spans. The truss spans are heavily constructed, using three truss lines per span. The outer truss lines use solid members and riveted connections. The inner truss line uses built up members, which consist of a tight lacing and heavier connections. All three truss lines use a variation of the Warren pattern, which includes alternating vertical members. Historic photos from 1923 show a slightly different design, with no large plates at the connections on the outer trusses. This photograph also shows that the original outer trusses utilized similar members to the current structure. It is unknown if the original 1887 outer trusses were strengthened, or if they were replaced entirely. It appears that the stringers were replaced in 1931, but the floorbeams appear to be original to the 1887 bridge.

Railroads often rebuilt truss and girder bridges by adding additional lines of structure, which greatly increased the loading capacity of the bridge. These additional lines could either be reused from another structure, or fabricated new for installation at an existing structure. On this bridge, it appears that the center truss was fabricated new, and is considerably heavier than the outer trusses. The Warren truss pattern became popular for railroad use in the early 20th Century. This simple design provided sufficient strength and durability without sacrificing economy, and quickly became the favorite truss design of railroads. Since the 1931 construction, the bridge appears to have had few alterations. A timber helper bent has been added along the west abutment to support cracking pedestals, and some repairs can be noted throughout the bridge. Overall, the bridge appears to be in fair to good condition, with no significant deterioration noted. The author has ranked the bridge as being regionally significant, as it is an excellent example of a large multispan truss bridge.