The large bridge-repair project on Interstate 470 that the Missouri Department of Transportation has been warning motorists about will start this week.

The resulting lane closures will affect I-470/Missouri 291 from 39th Street south to across the Little Blue River, as well as ramps at I-470/Interstate 70 and could cause traffic delays as long as 50 to 75 minutes during peak travel times, by MoDOT estimates.

MoDOT announced Monday that intermittent lane closures will begin starting at 8 p.m. Thursday along that stretch of I-470/M-291, as well 39th Street between Viking Drive and Arrowhead Avenue on either side of the overpass, for pavement marking, striping and barrier work.

By Monday morning (Aug. 13), the outside (right) lanes of I-470/M-291 will be closed until approximately early September. All loop ramps at the I-470/I-70 interchange will be closed as early as Friday until early September. For detours, MoDOT suggests using 39th Street, Lee's Summit Road and Blue Parkway to make elongated U-turns.

MoDOT advises motorists to avoid the area if possible, leave early if necessary and use the zipper merge when the highway goes down to one lane.