The Missouri Department of Transportation will celebrate the completion this month of an interchange near Warren County’s eastern limits as part of the Improve I-70 program.

The Interstate 70 and Highway W/T interchange in Foristell is a “divergabout,” which combines a “diverging diamond” type interchange and a roundabout, according to MoDOT. 

“At Foristell, the divergabout is open,” Improve I-70 East Team Project Director Kim Trainor told attendees at a construction update meeting for the project Monday, Oct. 5, in Wentzville.

“However, we do still need to do some overhead sign trusses. Those trusses and signs are still being manufactured, but we’re hopefully going to have them soon, and then we have some temporary lighting up, but permanent lighting will be placed up soon as well,” Trainor said. She added that there are various other tasks to take care of.

“We’re still nailing down a few things, but we are going to do some type of interchange celebration on Oct. 16,” she said. “The time has not been determined yet, but it will be sometime in the afternoon, and it will be held at the commuter parking lot right next to the interchange.”

Work on I-70 is also continuing in the Wentzville area, Trainor said, where MoDOT is rolling out a new striping configuration for the entire corridor, which will feature black paint alongside the more familiar white dashed lines to indicate where lane changes are allowed.

“If you’ve driven the eastbound segment, you’ll notice that the striping looks different, and this is going to be how we will stripe all of I-70, the whole 200 miles,” she said.

“It’s the introduction of more contrast and more of a lead-lag, so that during the day, sometimes it’s hard to to see the white stripe, but hopefully that black line will help make things more visible, especially when the sun is hitting the pavement just right in the mornings, but then at night the white should pop for everybody to see at night,” Trainor added. “This is something new that MoDOT is doing.”

Trainor also provided an update on continuing work on I-70 in Warren County. From the Route MM/West Warrenton Boulevard interchange to Highway 47, work is continuing from west to east, she said.

“We have I-70 in the Phase 2 condition, which has the eastbound traffic shifted to the right, and work is occurring in the median,” she said. “We have nightly lane closures in the eastbound direction and intermittent lane closures in that westbound direction. We’re going to be in this configuration through the spring or summer of next year.”

For the next segment, which begins east of Highway 47 and extends to the Wright City rest area, eastbound traffic was shifted to the left as of Monday, but Trainor said MoDOT was expecting the traffic configuration to change by the end of the week.

“So tentatively on Oct. 8, eastbound is going to shift right, then we need to redo the striping and some other things, and then on the 12th, westbound will shift left into this area,” Trainor said, adding that this would give the contractor the ability to completely remove the westbound lanes and do all the necessary construction at once. “We anticipate being in this configuration over the winter and into the spring or summer of next year,” she said.

For the segment from the Wright City rest area to the Route F/J interchange, MoDOT is currently in Phase 1 of its project, “which has the eastbound traffic shifted to the left and that work on the future shoulder is occurring, and no impacts to westbound,” Trainor said.

Tentatively, she said, in November, MoDOT plans to begin Phase 2 for this segment, shifting eastbound traffic to the right and allowing work in the median, with occasional lane closures for westbound traffic.

“We anticipate this configuration through the spring and summer of ‘27,” she said. 

“At Wright City, work continues on the new roundabout that is on the south side of I-70,” Trainor added.

As of Monday, the Wright City roundabout area remained closed, but MoDOT was hoping to partially reopen the area to traffic later in the week, Trainor said.

“Once we reopen Veterans Memorial Parkway, traffic will drive on the new pavement through the area, and that will allow the contractor to construct the northern half of the new roundabout that will serve the area,” she said.

“In the area east of Wright City to the St. Charles County Line, we are in that Phase 3 condition, which has the eastbound and westbound essentially shifted all to the one side, so that construction is occurring all in the westbound direction. We anticipate having this section complete before the end of the year.”