A major Missouri Department of Transportation (MoDOT) investment is transforming the Interstate 55 corridor in Jefferson County, improving safety, reducing congestion, and strengthening one of eastern Missouri’s key freight corridors. The $246 million design-build project will expand capacity, reconstruct bridges, improve interchanges, and eliminate long-standing traffic bottlenecks that have impacted commuters and commercial carriers alike.
Construction began in early 2024, with approximately 80% of the project expected to be complete by fall 2026. While coordination with rail partners has shifted final completion to spring 2027, the project remains on budget and is expected to accommodate approximately 82,000 vehicles per day once finished.
The improvements will enhance travel reliability and support more efficient freight movement throughout the St. Louis region, reinforcing the area’s role as a critical multimodal logistics hub.
