Fox River Bridge

The $95 million Fox River Bridge replacement project was one of the largest single contract awards in the $2.5-billion Jane Addams Memorial Tollway (I-90) Rebuilding and Widening Project. Each day over 100,000 vehicles cross the 1315-foot-long, 8-lane twin bridge designed by Stanley Consultants. The combination of a novel bridge-under-bridge design with a gantry system for beam erection resolved a plethora of complex requirements – maintain six lanes of traffic during construction, protect the adjacent forested fen, avoid impacts to the river and endangered fish species, reduce the number of piers and expansion joints and avoid overhead lines. The award-winning bridge-under-bridge design permitted construction of the new substructure underneath the existing superstructure with no impact to the traffic above. A space-saving gantry system eliminated the need for a large crane, avoiding impact to the forested fen.