Missouri broke ground Thursday on a major infrastructure project: the long-awaited expansion and modernization of Interstate 70.

Running east to west across the state and connecting Kansas City to Columbia and St. Louis, I-70 is a significant thoroughfare for commuters, commercial truckers and travelers alike. The project will widen the interstate to three lanes in each direction alongside other improvements.

The I-70 improvement championed by Gov. Mike Parson is broken up into six segments between Blue Springs and the St. Louis suburb of Wentzville. The first segment, a 22-mile stretch from Columbia in central Missouri to Kingdom City, will begin construction in July and is expected to wrap up in 2027. Altogether, the statewide project is expected to take around seven years to complete.

“We look forward to completion of the entire I-70 corridor by late 2030,” state highways and transportation commission chair W. Dustin Boatwright said Thursday in a press release for the ground-breaking.

So how will traffic affected on the interstate in the near future, and when will construction come to the Kansas City area? Here’s what to know about the I-70 expansion.

How does Missouri plan to improve and expand I-70 across the state?

The biggest upgrade I-70 will see on its way through Missouri is the addition of an extra lane in each direction, growing the interstate into a three-lane divided highway.

“Expanding I-70 to six lanes has been needed for decades. It has been talked about for decades,” Missouri state Senator Lincoln Hough of Springfield said Thursday. “Today, decades of talk turns to action.”

The project will also repave roads, modernize bridges, and improve interchanges between I-70 and other major roads. This work will be completed in six segments:

• Project 1: Columbia to Kingdom City

• Project 2: Warrenton to Wentzville

• Project 3: Blue Springs to Odessa

• Project 4: Kingdom City to Warrenton

• Project 5: Odessa to Marshall

• Project 6: Marshall to Columbia

Project spokesperson Lairyn McGregor said that crews plan to keep both lanes of I-70 open during peak times as construction begins, but that drivers may see traffic reduced down to one lane overnight.

“Since the Columbia to Kingdom City section of this project is in the middle of the state, motorists traveling across the state could see impacts during construction,” she wrote in an email to The Star. “We would ask that motorists plan ahead, drive the posted speed limits, buckle up and put their phones down.”

When will Kansas City be most impacted by the I-70 expansion?

The segment of the project closest to Kansas City will expand I-70 between Blue Springs and the small city of Odessa around 19 miles east. This segment is scheduled to begin construction third out of the project’s six total segments.

According to the Missouri Department of Transportation, a contract for this segment will be awarded around the spring of next year, with construction beginning soon afterward. This segment should be complete around the fall of 2028.

“We won’t know what the Blue Springs to Odessa project will look like or what traffic impacts it will have until we select a best-value proposer in 2025,” project spokesperson Lairyn McGregor told The Star.

Do you have more questions about infrastructure initiatives in Missouri or Kansas? Ask the Service Journalism team at kcq@kcstar.com.