Tuesday, May 30, 2023

Illinois 146 widening, roundabout construction to begin in 2023

By Jordan McBride

The Illinois Department of Transportation is in the planning and early design stages for dramatic roadway improvements in Vienna. The project will take place on the east side of town and consists of widening Illinois Route 146 to three lanes: two travel lanes and a two-way left turn lane.

The widening will begin west of Vienna City Park and continue to the east to the intersection of Illinois 146 and Red Bud Lane. The intersection of Red Bud Lane, Old Metropolis Road, and Illinois 146 will be the site of a roundabout.

The project will also feature a 10-foot wide shared-use path that will tie into the Tunnel Hill State Trail and end at the roundabout. The road will be resurfaced beginning east of the intersection with U.S. 45 and ending at the ramps for eastbound Interstate 24.

Pictured above is the proposed widening of Illinois Route 146 from just West of the Vienna City Park to the entrance and exit ramps of Interstate 24. The project will also include resurfacing of Route 146 from the intersection at Illinois Route 45 to the interstate. The maps are provided by IDOT and are available for public viewing online and at the Vienna City Hall. Landmarks have been added for clarity.


There are two separate projects scheduled for Illinois 146 inside these project limits. The first project replaces the bridge over Little Cache Creek and construction on that bridge will begin in late summer 2021 and extend through 2022. Construction on the widening project will begin spring 2023 and is estimated to be completed within that year.

IDOT released a statement laying out the planning phase of the project:

“In the early stages of the design process, there were different options considered for the project. For example, one option looked at widening on both sides of the road and installing the trail on the [north] side of Illinois 146. Another option consisted of widening on the [south] side and installing the trail on [that side]. The option that was chosen has the lane widening on the [north] side and two different trail offsets, depending on the available right –of way. This option was selected because it had the smallest right-of-way impact and allows for the least amount of traffic impact during construction, and it had smaller utility impacts of the other scenarios.”

The agency takes care to note that the intersection portion of the project will feature construction of a “modern roundabout”.

Modern roundabouts differ from traditional traffic circles or rotaries in that they have much slower traffic flow and are safer. Safety is a key part of the choice to use the roundabout. IDOT reports at least 29 separate crashes at the intersection since 2016. According to federal transportation officials roundabouts like the one proposed for this project essentially eliminate high-speed and right-angle crashes, which are often the most fatal.

Initial construction costs can be somewhat higher with a roundabout compared to a traditional four-way signal intersection, but maintenance is often much cheaper. Without signal lights to maintain and with the reduced number of potential accidents, more and more state and local governments are looking to integrate roundabouts for safety future cost-saving purposes.

A website will be available until May 17 and in-person displays are available at the Vienna City Hall at 205 N 4th Street. The website features several images of the proposed construction, as well as animations of traffic flow and informational videos.

Questions about the project can be directed to: Carrie Nelsen, District 9 Program Development Engineer at (618) 549-2171 ext. 280. There is also an online comment form available.