Opening South Metro Access

Crawford, Murphy & Tilly (CMT), designed the largest and, arguably, most complex section of the I-355 south extension projects, targeted to accommodate the needs of the growing south suburban communities of the Chicago metro area.

CMT developed multiple interchange/configurations, prepared an interchange design study and provided plans, specifications and cost estimates for the 2.5 mile, six-lane highway that included an interstate to interstate interchange at I-55. Interchange improvements enhanced an existing four ramp trumpet interchange making it a major eight ramp interchange with three directional flyovers. CMT completed the $170 million project design under budget and on time taking just 13 months from the official notice-to-proceed to update contract documents, prepared by CMT in 1996, to current standards. The Illinois Tollway split the project into three separate, major design/construction contracts. This section of the Tollway program represents a monumental effort of coordination of six subconsultants, five CMT offices and 12 reviewing agencies. As project managers, CMT engineers coordinated the efforts of the subconsultants, the Illinois Tollway, the Illinois Department of Transportation and the three counties touched by this project.