C&NW Eighteen Mile Creek Bridge

Located on the west side of Grand View, this large deck truss viaduct carries the former Chicago, St. Paul, Minneapolis & Omaha Railway over Eighteenmile Creek. The first bridge at this location was likely a tall timber trestle bridge. During the late 1880s and early 1890s, the Omaha Road made significant upgrades to this route, replacing timber bridges with steel and stone. This bridge was constructed in 1889 to replace the previous timber bridge. Currently, the bridge consists of three 80-foot, 7-panel riveted double intersection Warren deck truss spans, with four 50-foot, four 20-foot and two 10-foot deck plate girder spans. The bridge is set onto steel towers, stone substructures and is approached by three timber pile trestle spans on the east end. The east approach was added at a later date, and the timber pile pier supporting the eastern deck girder span is set onto a concrete footing, which appears to have been constructed in approximately 1920. The center towers, supporting the trusses use the 20-foot spans, while the outer towers supporting the 50-foot spans use 10-foot spans. The towers are composed of a combination of laced and slender solid members, which rest on stone pedestals and piers. Lassig Bridge & Iron Works fabricated the truss span, while an unknown contractor completed the substructures. Typical of bridges in this area, the stonework was quarried at an unknown location, and consists of a reddish colored stone. The truss span consists of a combination of solid and laced members, typical of spans of this design. The viaduct is an impressive 60-plus feet above the surrounding valley, and is the largest structure on this line.

While lattice truss spans were relatively uncommon through the United States, the Chicago & North Western Railway (C&NW) and Omaha Road used the design extensively. Other railroads in the Midwest also occasionally used the design, although not as frequently. Engineers for the C&NW and Omaha Road favored the design, due to its resilience and greater strength without sacrificing economy. Metal lattice truss designs were initially developed for railroad use in the 1870s, often using deep spans with numerous intersections. Through the mid-1880s, short to medium length spans were simplified into double intersection spans, as seen on this bridge. Most lattice spans through the 1880s and 1890s were constructed by the Lassig Bridge & Iron Works, which produced a vast majority of iron and steel bridges for the C&NW and Omaha Road during this era. While the Omaha Road stopped using lattice trusses in the early 20th Century, the C&NW continued to use lattice truss designs nearly exclusively into the 1920s. This shift represents one of the few known instances where C&NW and Omaha Road engineers had differing opinions on bridge design. Since abandonment, the bridge has been converted into an ATV/snowmobile trail, and is currently owned by Bayfield County. Overall, the bridge appears to be in fair to poor condition, with significant failure to the west abutment. Repairs have been made using chains under tension, but further repairs will be needed to stabilize the abutment. The remainder of the structure appears to be in fair to good condition, and the superstructure retains excellent structural and historic integrity. The author has ranked this bridge as being regionally significant, due to the truss design, age and imposing nature of this bridge.