Tollway committee recommends $35.27 million master-plan contract for I‑355/I‑88 interchange study

The Development Oversight Committee of the Toll Highway Authority on Jan. 28 recommended a $35,269,281.30 contract to Hansen Professional Services Incorporated to perform master‑plan and design services for improvements at the I‑355/I‑88 interchange.

The master plan contract, the committee heard, will fund traffic, environmental and roadway studies, structure inspections, cost estimating, scheduling and stakeholder coordination needed to define the interchange footprint and enable follow‑on design and construction contracts. "This contract initiates our efforts for providing congestion relief and improving travel efficiency through this interchange, which is one of the most heavily traveled on the system," Chief Engineering Officer Manon Nasher said.

The interchange connects two Tollway interstates and serves a mixed commercial and residential area including Downers Grove, Glen Ellyn, Lisle, Lombard, Wheaton and Woodridge. Nasher told directors the interchange carries about 300,000 vehicles per day and estimated a planning cost range for the overall project between $1.5 billion and $2.5 billion; that range will be refined by the master plan. She said the study will evaluate roughly 11 miles of mainline tollway in the area (about 6 miles on I‑355 and 5 miles on I‑88), 33 bridges and 74 retaining walls.

The study is expected to follow three primary phases, with the master plan itself anticipated to take about two years. Nasher said the program team intends to overlap phases where practical and bring design contracts to the board before the master plan is fully complete to accelerate construction where feasible.

A board member asked whether portions of construction could begin sooner than the full plan timeline. Nasher replied the team aims to "get to construction as soon as possible" and to identify early enabling contracts that avoid lengthy utility relocations or intergovernmental agreements.

Nasher also said the consultant team will plan contract packaging to maximize opportunities for small and diverse businesses; the Hansen contract includes a stated commitment of $15,000,000 to diverse and veteran‑owned firms. The presentation noted coordination will be required with roughly 20 agencies and that the project footprint is constrained by existing utilities and the Morton Arboretum property adjacent to the interchange.

Executive Director Cassandra said the Bridging the Future program, which the board approved last month, fully funds the master plan contract. "It's fully funded by the bridging program," Cassandra said, calling the program the catalyst that allows the Tollway to advance the studies.

The committee recommendation to award the Hansen contract was taken as part of a consolidated vote on engineering items 1–10 and advanced to the board; the consolidated approval was recorded by voice vote and individual roll‑call tallies were not specified in the transcript.

The master plan will set a framework for future design and construction contracts; Nasher said the goal is to deliver benefits to customers by improving mobility and access while planning for long‑term reconstruction needs.

Next steps include executing the Hansen contract, conducting the multi‑discipline studies, and returning recommendations and design contracts to the board for subsequent approval and contracting.