Project Images Tri-State Tollway reconstruction Project Summary The Illinois Tollway selected Hanson to provide engineering services for the largest construction contract ever awarded by the Illinois Tollway. Hanson completed one of the first phases of the Illinois Tollway’s $5.3 billion, 10-year Congestion-Relief Program — a $136 million reconstruction of a section of the South Tri-State Tollway through Chicago’s south suburbs — providing design-section engineering services for the widening and reconstruction of approximately 3.6 miles. The project included a complicated combination of constraints including heavy traffic, poor soil conditions, shallow bedrock, an urban setting with tight rights-of-way and utility conflicts, and other environmental considerations such as wetlands impacts, archaeological findings and sensitive resources. Hanson’s design included roadway and bridge reconstruction and widening, providing an eight-lane pavement section from the I-80/94/SR394 Interchange to the Halsted Interchange as well as a 10-lane pavement section from the Halsted Interchange to the Markham Yard Bridge. The reconstruction of the Halsted Interchange included adding a southbound collector-distributor road, modifying the existing toll plaza, and constructing a new toll plaza with non-stop electronic toll collection capabilities. Additionally, the 3.6-mile section included four pairs of mainline bridges; three bridges carrying local streets over the tollway; two bridges carrying railroads over the tollway; a full cloverleaf interchange at Halsted Street (Illinois Route 1); and a smaller service interchange (Lincoln Oasis). Hanson also provided: geotechnical recommendations, rock cut evaluation and retaining wall design, traffic engineering, field survey and survey data processing, erosion and sediment control design and grading plans, permanent and temporary roadway lighting, drainage design, permanent and temporary relocation of the Illinois State Toll Highway Authority’s communication network, fiber optics and utilities, noise abatement barriers and differential height median barriers, geometric design alternative evaluation, and conceptual planning for maintenance of traffic for 5.2 miles and detailed design for maintenance of traffic for 3.6 miles including temporary signal design. To accelerate project delivery, Hanson used innovative delivery methods — specifically, performance specifications — to allow the Tollway to benefit from a competitive construction marketplace.