AASHTO Journal - Illinois DOT Finishes Major I-55 Interchange Project

The Illinois Department of Transportation recently hosted an event celebrating the completion of a $93.5 million project to reconstruct a new interchange at I-55 and Illinois 59, which also incorporated other highway corridor improvements.

[Above photo by the Illinois DOT]

Located between the towns of Joliet and Shorewood, the project converted an interchange with partial access between I-55 and Illinois 59 into a full diverging-diamond design to enhance traffic flow and safety throughout the area.

Prior to rebuilding the interchange, only northbound I-55 could exit to northbound Illinois 59 and from southbound Illinois 59 to southbound I-55. Now, thanks to the new interchange design, both directions of I-55 can access both directions of Illinois 59 and vice versa.

Additionally, the project relocated and reconstructed East Frontage Road; providing necessary distance from the interchange, with auxiliary lanes added to I-55 between Illinois 59 and U.S. 52 improving safety, boosting efficiency and reducing conflict points by better accommodating vehicles entering and leaving the interstate.

“The completion of the interchange at I-55 and Illinois 59 will soon provide a safer and more efficient transit experience for the Will County community while simultaneously boosting the local economy,” Governor J.B. Pritzker (D) in a statement. “This milestone marks another step forward in our mission to improve safety, mobility and quality of life throughout Illinois.”

“The new interchange with Illinois 59 combined with other improvements to I-55 will greatly improve the flow of people, goods and commerce through the region while setting the stage for more jobs and economic development,” added Illinois DOT Secretary Omer Osman. “This project is a long-term investment that makes Will County an even better place to work, play, grow your business and raise a family.”

Other components of the project include the modernization of the Illinois 59 intersection with Seil Road; the addition of new sidewalks and connections to the existing local system of trails, including improved pedestrian and bicycle access across I-55; plus new lighting, modernized traffic signals, and the construction of noise/retaining walls along I-55.

The Illinois DOT noted that, as construction of the project winds down, work will continue on the multiuse path, installation of a new traffic signal at Illinois 59 and Seil Road, landscaping and other miscellaneous items into early 2025.

The agency added that this interchange reconstruction effort is part of its overall I-55 at Illinois 59 Access Project, funded in turn by the “Rebuild Illinois” capital program passed in June 2019.