Missouri Route 141 and Interstate 64 Interchange Improvements in St. Louis

What is the problem?

The interchange between southbound Route 141 and I-64 is congested. Regularly, traffic on the north I-64 outer road backs up on the ramp to southbound Route 141 during afternoon rushes, as does the ramp from eastbound I-64 to southbound Route 141.  This congestion can potentially lead to increased crashes along the corridor. At this time, this area sees about three times the crashes that one might see on similar roadways across the state of Missouri, mostly on the ramp from eastbound I-64 to northbound and southbound Route 141. 

What work is planned?

To reduce congestion near the westbound I-64 ramp, the plans include widening the exiting ramp to add another turn lane, which will split into two right turn lanes at the signal for northbound Route 141 to westbound I-64 with the right most lane being able to make a yielding right turn onto Route 141. This will give three lanes to southbound 141 from westbound I-64 (two of those lanes will be able to make a yielding right turn onto southbound 141.) 

To improve safety for those making a right turn from eastbound I-64 to route 141, the plans include widening the existing ramp from the bridge underpass to Route 141. The turn lane will also be widened, and Route 141 will be widened between that exit ramp and the roundabout at Woods Mill. This will provide a dedicated lane for people turning right. In addition, the current barrier wall will be shortened to a six-inch median to provide better visibility for those people turning right.