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W. Monroe Street

Passing Monroe St bridge on the way to winter storage - 2014

This is the first and only bridge built at West Monroe Street. Planning and design work began in 1913 and construction started in 1915. Labor strikes, court injunctions, and material shortages all contributed to the long construction period for this bridge.

Initially, the Union Station Company had oversight responsibility of the bridge construction. The Chicago Division of Bridges took over this responsibility in 1917.

Bridge tender houses are placed on the southwest and northeast corners of the bridge and were rebuilt in 2008. Railings have been restored to near "original."

The designers of this bridge faced some unique issues. The west side of the bridge abutted the railroad tracks for Union Station which would have been the “normal” location for the bridge abutment and tail pit for the fixed trunnion bascule bridge. In addition, there was a cross town water tunnel crossing the river diagonally here, and on the east bank there were two freight tunnels.

Initially a single leaf bascule was considered for this location but Edward Bennett of the Chicago Plan Commission was against such a design because it lacked the symmetry of a double leaf bascule. The compromise was to custom build each leaf of the double leaf bridge.

On the west bank, a heavier than usual counterweight was used to provide for a shorter radius of rotation which avoided interference with the railroad. The east leaf was similar to earlier bridges, with the exception of some of the foundation details.