A reminder from MoDOT on how to Merge Safely
Merging on highways can occur on highway entrance ramps, at exit ramps connecting two major roads or at work zones or crash sites where lanes are restricted. The safest merging is to think about two lanes merging into one. Not one lane merging into the other.
Most motorists start to merge as soon as they see warning signs and learn which lane ahead is closed. When the highway is not heavily congested and traffic is able to move at the speed limit, it is best to merge early into the open lane.
However, in dense, slow-moving traffic, the open lane fills quickly. Motorists are forced to slow in the closed lane and may become anxious to merge. When a driver in the closed lane can’t move into the open lane in time, the closed lane ends, forcing the vehicle to suddenly stop. The vehicle must now join traffic from a dead stop. This driving behavior can lead to sudden lane switching, inconsistent driving speeds that cause crashes, long back-ups and road rage.
Research shows these behaviors decrease and traffic moves more smoothly when motorists use both lanes until reaching the defined merge area and then alternate merging every other vehicle in “zipper” fashion into the open lane.
By using two full lanes of traffic until the merge, you reduce the difference in speed between the two lanes. The length of back-ups is reduced 40-50 percent. When both lanes continue to move slowly, everyone is equally delayed, which reduces road rage.
Watch for signs instructing motorists to resist the urge to merge and do the “zipper” merge where the lane closure occurs.