Traffic congestion is expected through Friday, October 4, at Highway 13 and Route O north of Springfield.
MODOT is working on a new J-turn at the intersection, which will replace the traffic signal there. One northbound lane of 13 is closed, and drivers are urged to find alternate routes such as Highway 160, Route H and Route 65.
The work is expected to be finished by noon on Friday.
Once the work is finished, there will no longer be a traffic signal at the Highway 13 and Route O intersection.
MODOT officials are making the changes to improve safety. J-turns are "a much safer alternative to traditional intersections on a four-lane high-speed highway," according to MODOT.
Drivers at a J-turn intersection who want to make a left turn must first turn right, traveling in the same direction of traffic, merge into the left lane and then make a U-turn.
A University of Missouri study found that J-turn intersections can reduce injury and fatality crashes by up to 53 percent.
