Attention Chicago-area drivers: Traffic on Kennedy is about to become more congested and “major delays are expected” as a year-long, major construction project will soon take over an already busy section of the freeway.

According to Illinois Department of Transportation officials, a $150 million rehabilitation project of the Kennedy Expressway from the Edens Expressway Junction to Ohio street is scheduled to begin March 20.

The project, which is divided into three phases and includes rehabilitation of sidewalks, express lanes, overhead sign structures, lighting and three dozen bridges, is expected to last through 2025.

While officials say the rehabilitation will “increase safety, reduce maintenance costs and improve traffic flow,” IDOT also warns that “travel delays are expected,” and “alternate routes are strongly encouraged.”

Here is an overview of what we know about the project, and when and where construction is expected to take place.

Where at Kennedy is construction taking place?

According to IDOT, the entire project will span approximately seven miles from the Kennedy Expressway (Interstate 90/94), from the Edens Expressway Junction (Interstate 94) to the Ohio Street exit.

In addition, work is also planned for Hubbard’s Cave — the tunnel beneath where Hubbard Street crosses the Kennedy Expressway — from Grand Avenue to Wayman Street.

Which lanes will be closed and when?

IDOT says the project will occur in three stages, with the first phase beginning March 20.

Step 1: Inbound lanes, Spring 2023 up to and including autumn 2023

The first phase of construction will affect the inbound Kennedy, with “two main line inbound lanes closed at a time.”

“Motorists should expect overnight lane changes and lane closures, along with various ramp closures,” an IDOT release said.

A press release from the agency further states that reversible express lanes will remain open in the inbound direction “to help minimize traffic impact.”

During the summer months, the inbound tunnel under where Hubbard Street crosses the Kennedy Expressway will also be affected.

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“Later this summer, painting and installation of new LED lighting will begin on the inbound Hubbard’s Cave between Ohio and Lake Streets,” IDOT says.

According to officials, Stage 1 projects are expected to be completed by the fall of 2023, with “all lanes and ramps reopening and express lanes resuming normal operations.”

Stage 2: Express Lanes, Spring 2024 through Fall 2024

IDOT says the second phase of the project will tackle the reversible express lanes.

According to the release, next year, the express lanes will be closed to accommodate a rehabilitation of the Reversible Lane Access Control System known as REVLAC.

“Additionally, major lane closures will be required to accommodate painting and installation of new LED lighting in both directions of Hubbard’s Hollow, between Ohio and Lake streets,” IDOT says.

According to officials, Phase 2 projects are expected to begin in the spring of 2024, and be completed in the fall of 2024.

Stage 3: Outgoing Kennedy, spring 2025 to late fall 2025

The third phase of construction, IDOT says, will address the outbound lanes of the Kennedy Expressway.

According to the release, two outbound lanes on the main line will be closed at a time, with lane changes, overnight lane closures and various ramp closures. However, “the reversible express lanes will remain open in the outbound direction,” IDOT says.

In addition, work on outbound Hubbard’s Cave will continue between Ohio and Lake Streets, IDOT says.

Officials say the third phase is expected to begin in spring 2025 and be completed by late fall 2025.

When will the construction be over?

According to IDOT, the overall project is expected to begin on March 20, 2023, beginning with inbound Kennedy lanes. It will be completed in stages, IDOT says, and is expected to be completed in “late 2025.”

“Motorists should expect significant delays and allow extra time for trips through this area,” IDOT says.

The Kennedy Expressway has been officially open since November 1960, but according to IDOT, the last major rehabilitation project on the roadway was completed in 1994.