The departments of transportation from Illinois and Missouri held a ribbon cutting ceremony on Monday to celebrate the completion of the $496.2 million Interstate 270 Chain of Rocks twin bridges project.
The bridges replace one built in 1966 with two lanes in each direction and narrow shoulders. Groundbreaking was held in 2023, and the eastbound span opened in late 2024. The westbound bridge will open on Nov. 16.
The bridges carry two lanes in each direction over the Mississippi River. After guardrails are installed next construction season along with median work and the painting of girders and beams, this will increase to three lanes in each direction.
The Illinois Department of Transportation oversaw the project with both states sharing costs. The project is part of a combined $531.6 million investment to improve safety and mobility along the I-270 corridor. Missouri is reconstructing the Riverview Drive interchange just west of the bridge for $35.4 million.
“The I-270 bridges are another transformational project under Gov. Pritzker that are preparing an entire region for long-term economic success,” Illinois Transportation Secretary Gia Biagi said. “We are especially proud to deliver this project with our partners in Missouri. Working together, we have positioned our two states as a freight hub that can support and create good-paying jobs well into the future.”