Cairo Mississippi River Bridge

Information and Findings From Missouri's Historic Bridge Inventory

Bridge Features

superstructure: steel, rigid-connected cantilevered through truss; 21 plate girder approach spans on Illinois side; 13 plate girder approach spans on Missouri side

substructure: concrete abutments, wingwalls and piers

 floor/decking : asphalt/ concrete deck over steel stringers

Alterations: deck replaced, 1981

Other Features: upper chord and inclined end post: 2 channels with cover plate and double lacing; lower chord: 2 channels with lacing, top and bottom; vertical: 4 angles with lacing ( 4 angles with continuous plate at some points); diagonal: 2 channels with double lacing; lateral bracing: 4 angles with lacing - top, 2 angles - bottom; strut: 2 angles with lacing and "X" bracing; portal strut: 2 angles with lacing; floor beam: plate girder; guardrail: 3 channels; Missouri approach bridge plate: American Bridge Co. USA 1928

Erection Cost: $3,109,311.86

Discussion of Bridge

Cairo, Illinois, located at the confluence of the Mississippi and Ohio rivers, was faced with the problem of bridging not one, but two, major rivers to link with outlying areas. A railroad bridge over the Ohio was completed in October 1889 by the Illinois Central Railroad. Consisting of a series of pinned Whipple through trusses, supported by stone piers, it was the longest metallic bridge in the world when completed, and its 518-foot channel spans represented the ultimate extension of the Whipple truss. A vehicular bridge was a long time coming, however. While ferryboats carried wagons and cars across the two rivers, the citizens of Cairo hopefully promoted a single structure with a Y-shaped configuration, with one leg over the Mississippi and one over the Ohio. The structure would be paid for by the government, and its construction and maintenance costs would be defrayed by tolls.

When the government was not forthcoming with the funds in the 1920s, the community instead turned to Harry E. Bovay, an Arkansas capitalist. Bovay had built one successful toll bridge in his home state, and he was looking for a larger bridge project, when he contacted the Cairo Chamber of Commerce. Under Bovay's direction, an organization was established to promote the bridge, a Congressional charter was secured, bonds were sold, and the venerable J.A.L. Waddell, of Waddell and Hardesty, was commissioned to design it. The contract for the substructure was awarded to the Missouri Valley Bridge and Iron Company of Leavenworth, Kansas, a veteran of several Mississippi and Missouri River bridge projects. The silicon steel superstructure was to be fabricated and erected by the American Bridge Company of New York.

Work on the piers began in July 1927. The channel piers were sunk with agonizing tedium by means of pneumatic caissons. Work on the cantilever spans began in 1928. "The steel work progressed much faster than the foundation work," reported the Cairo Evening Citizen. "You could almost see the bridge creep across the river. The span was cantilevered out over the water half way to the next pier, and a support was put in, resting upon a cluster of piles and the rest of the distance was jumped .... There was no long stretch of piling filling the entire span, as in the construction of the Illinois Central bridge. The method of construction showed the progress made in bridge building between 1887 and 1927, forty years." After several weather-related delays, the trusses were completed and the bridge opened ceremoniously in October 1929. The original Cairo Bridge and Terminal Company operated it as a toll structure until the Cairo Bridge Commission acquired it in 1942. This quasi-public agency held the bridge until the bonds were retired in May 1954 and it was turned over to the states of Missouri and Illinois. The original deck was replaced in 1981, but the Birds Point Bridge remains otherwise intact as a pivotal interstate crossing.

Almost a mile long, the Cairo was a stunning achievement for the citizens in southern Illinois and the bootheel of Missouri - the fulfillment of some forty years of boosting. It played a critical role in transportation and commerce in a three-state region, as it linked Cairo with Missouri and Kentucky. The bridge is noteworthy as a superlative example of long-span truss construction. With its 700- foot, silicon steel spans, it is the longest of Missouri's cantilevered through trusses - a historically and technologically significant highway-related resource.

Bridge Considered Historic By Survey: Yes

View Original PDF Historic Bridge Inventory Sheet