Plans for I-70 widening relatively final. Here's when construction is expected to start

New, but familiar highway elements in the next three years will change the landscape of Columbia as construction readies to start on projects that will expand Interstate 70 to six lanes.

Design-build firm Millstone Weber in partnership with Jacobs Engineering plan to start work in the area of the I-70 and U.S. Highway 63 connector after July 4, said Jeff Gander, Missouri Department of Transportation project director for the Columbia to Kingdom City section of Improve I-70.

"We're not totally locked in. Our plan is to start sometime after the Fourth of July. Construction has to be completed by the end of 2027," he said.

Columbia area residents particpate in a public input meeting Wednesday regarding Improve I-70 projects that will impact Columbia to Kingdom City.
Columbia area residents particpate in a public input meeting Wednesday regarding Improve I-70 projects that will impact Columbia to Kingdom City.

While plans are relatively finalized for the project, MoDOT and Millstone Weber still wanted to get some final public feedback on finer details of the plans, Gander said. Meetings were held Wednesday and Thursday in Columbia and Kingdom City, respectively. For those that missed the meetings and plans, a video rendering and more information is available through the project website. An online public comment form is available through May 23.

Plans for the connector

Plans at the connector have some distinct differences to what MoDOT previously had presented. Previous plans used a single-point urban interchange. This is an interchange where only left-hand turns are stopped by a traffic light. All right-hand turns are yielding turns to keep the flow of traffic moving around those waiting to turn left. Plans also include flyover ramps with direct connections from I-70 to U.S. 63 and vice versa.

The flyover ramps remain in plans, but what is now new from what was proposed by Millstone Weber are an underpass leading from Conley Road and onto Business U.S. 63; modifying the Business Loop 70 East and Conley Road intersection into a roundabout; a roundabout on Clark Lane at Hanover Boulevard with ramps off and onto I-70, including a Hanover underpass with pedestrian access; removing the left-hand exit ramp from westbound I-70 onto the Business Loop and instead putting in a roundabout where traffic comes off eastbound 70 into the roundabout or from the Business Loop to eastbound I-70 via the roundabout; and a roundabout on Clark Lane adjacent to the Socket Internet office leading on and off of I-70.

"When we put our (request for proposals) for this project we said you have to have two direct connects, improve traffic at the connector, improve traffic flow at U.S. 54 and you have to add a third lane in between there," Gander said, adding Millstone Weber took those parameters and ran with it. "The underpasses you see, that is all their idea."

Bob Leingang, center leaning over in black shirt, executive vice president and chief engineer with Millstone Weber, points to a section of plans Wednesday focused on the Interstate 70, U.S. Highway 63 connector to answer questions from area residents.
Bob Leingang, center leaning over in black shirt, executive vice president and chief engineer with Millstone Weber, points to a section of plans Wednesday focused on the Interstate 70, U.S. Highway 63 connector to answer questions from area residents.

The main section of the connector also rather than the MoDOT SPUI proposal, under Millstone Weber plans has it as a half-diamond interchange.

The underpasses and roundabouts "takes so much traffic away from the connector that it makes it function so much better," Gander said.

Rather than motorists having to contend with a three left turn lanes from Conley Road onto the connector, the Conley underpass will funnel motorists directly to the connector, Gander explained.

Construction timeline

The connector construction project is expected to take up the entire three year timeline. I-70 lane widening in this first section of the project will happen from Paris Road to St. Charles Road.

The second section is the I-70 lane from St. Charles Road to Cedar Creek. This is not expected to start until the later half of 2026 and conclude by project end in 2027.

More: These are the interchange enhancements sought for the I-70/U.S. 63 connector

Section three for the I-70 lane addition is from Cedar Creek to Route M, expected to start in late 2024 and run through early 2026.

The fourth section for the I-70 lane addition is from Route M to Kingdom city, where two new bridges and a roundabout interchange will be built on U.S. 54. This is expected to start in the latter half of 2025 and run through early 2027.

I-70 is expected to have two lanes open in both directions throughout construction. Work will be done behind barrier walls, so there may be some lane shifts, but overall traffic should not be impacted to heavily, except for construction zone motorist speed limits.

More: MoDOT names contractor for Columbia section of I-70 project. Here's when work will begin

Charles Dunlap covers local government, community stories and other general subjects for the Tribune. You can reach him at cdunlap@columbiatribune.com or @CD_CDT on Twitter. Subscribe to support vital local journalism.

This article originally appeared on Columbia Daily Tribune: I-70 construction expansion starts after July 4, will take 3 years