St. Charles Times

The Missouri Department of Transportation (MoDOT) has announced the commencement of its largest project to date, a $600 million initiative aimed at improving Interstate 70. The contractor team for this extensive endeavor has been selected, with construction set to begin in spring 2025 and an anticipated completion in 2028.

The improvements will take place primarily in St. Charles County and include significant enhancements to I-70 from Wentzville to Warrenton. Among the planned upgrades is the addition of a third lane in each direction and the reconstruction of existing lanes with new concrete and subgrade.

At Wentzville, I-70 will be expanded to five lanes in each direction through a current railroad bottleneck, which necessitates the construction of a new railroad bridge. Furthermore, there will be a complete reconfiguration of the westbound I-70 exit at Route Z. This change aims to prevent traffic exiting I-70 from "weaving" through incoming traffic from I-64.

Significant changes are also planned for the I-64/I-70 interchange at Wentzville. Two dedicated lanes will be built for the exit ramp from westbound I-64 to westbound I-70. Additionally, traffic will be directed into collector lanes that are physically separated from main traffic lanes on I-70 by barriers. These collector lanes will not merge with westbound I-70 until after Route Z exit, reducing current traffic weaving issues.

In Foristell, major expansions are intended to accommodate heavy truck traffic and growth in western St. Charles County. A new interchange featuring two separate bridges for northbound and southbound traffic and large roundabouts on both sides of I-70 is planned. These features aim to connect ramps to outer roads efficiently.

This comprehensive upgrade also includes adding a third lane in each direction along this stretch of highway.