The I-355 South Tollway Extension will connect one of Illinois’ fastest-growing counties to the Chicagoland area, increasing economic opportunity in the area and greatly reducing commuter times and congestion on local roads. CMT was selected by the Illinois State Toll Highway Authority as lead consultant for the planning and design of the largest section of the 12.5-mile extension.

CMT coordinated the work of two other consultants to widen a section of the existing tollway from four lanes to as many as ten, reconstruct the existing I-55 trumpet interchange into a three-flyover directional interchange, and develop a new tollway mainline on the south extension.

The South Tollway Extension Project was named the #1 North American Road Project for 2006 by Roads & Bridges magazine.