I-294 Tri State Tollway aerial view.

I-294 Roadway Reconstruction / Bridge Rehabilitation and Widening, O’Hare Oasis to Balmoral Avenue

As part of the 15-year, $14 billion “Move Illinois” capital program, the Central Tri-State Tollway (I-294) in Illinois is being reconstructed to increase capacity, alleviate congestion, and improve travel reliability. The tollway is a vital link to O’Hare International Airport, serving 220,000 travelers every day. Reconstruction will add a fifth general-purpose lane to the four-lane highway and convert the median shoulders into flex lanes for emergency use and potential future traffic management and/or transit uses.

Gannett Fleming was asked by the client to expedite phase II engineering services for the preparation of contract plans and specifications and project-related permits for reconstruction of 2.3 miles of I-294 between the O’Hare Oasis and Balmoral Avenue. The scope of the firm’s work included roadway, retaining wall, and noise wall design, as well as the reconstruction and rehabilitation of four bridges in the project area. New drainage structures and the modification of existing drainage system will handle storm runoff to alleviate roadway flooding and meet flex lane design criteria. A detailed maintenance of traffic plan kept all mainline travel lanes open during construction.

What We Did

Construction of this segment of I-294 was originally planned to start in 2023, allowing for an extended five-year design phase. When the Illinois State Toll Highway Authority decided to advance construction to meet expedited program goals, the Gannett Fleming team rose to the challenge. The firm delivered contract documents for $40 million of construction in less than four months, followed by a second contract for $60 million of construction less than 10 months later, allowing the authority to meet its revised construction targets.

Accelerated design required project rephasing from planned one-direction per year to inside reconstruction in the first year and outside reconstruction in the second. This provided time to secure permits and complete necessary right of way acquisitions and utility relocations. The rephasing also created a maintenance of traffic challenge: Four lanes of the tollway had to be kept open in each direction at all times. The solution was to provide temporary outside widening to shift traffic enough so that adequate workspace was created while maintaining four-lane travel.

Key Features

  • Delivered highly accelerated design of interstate reconstruction project meeting toll highway authority stimulus objectives.
  • Contract documents for $40 million out for construction in less than four months, with remaining $60 million out for construction less than 10 months later.
  • Temporary widening allowed maintenance of all mainline travel lanes during construction.
  • Daily coordination with Tollway, numerous adjacent project team consultants, and key stakeholders, including O’Hare International Airport, Federal Aviation Administration, Canadian National Railroad, Village of Rosemont, and Schiller Park.


  • Reduced traffic congestion for 220,000 daily motorists.
  • Added flex-lane median and new fifth lanes enhance mobility.
  • Improved access to and from O’Hare International Airport.


Illinois State Toll Highway Authority


Cook County, Ill.


Phase I Validation, Phase II Design

What are you looking for?
Privacy Preferences

When you visit our website, it may store information through your browser from specific services, usually in the form of cookies. Here you can change your Privacy preferences. It is worth noting that blocking some types of cookies may impact your experience on our website and the services we are able to offer.

Our website uses cookies, mainly from third-party services. Define your Privacy Preferences and/or agree to our use of cookies.