The stubborn snow is melting, and that means construction season can commence in Minnesota. A decade ago, the Minnesota Department of Transportation introduced the "zipper merge" to encourage easy traffic flow in construction zones, but the term continues to baffle motorists.
"I've never heard of the zipper merge," admitted taxi driver Bill Schmaus.
Moving over right away seems like it would be an extension of Minnesota Nice, but MnDOT says it makes traffic worse. That's why when a lane is closed in a construction zone, MnDOT instructs drivers to use both lanes of traffic until reaching the lane closure, then alternate cars like slats on a zipper into the open lane.
"Traffic flows very smoothly when that happens," Ken Johnson, with MnDOT told FOX 9 News. "You don't have to constantly accelerate, constantly brake."
A survey conducted by MnDOT three years ago found more than 60 percent of those who discuss transportation on MnDOT-sponsored online forums said they didn't know the zipper merge was the gold standard cited in the latest Minnesota Driver's Manual.
The issue lies in early merging. When drivers see a sign indicating a future lane closure, they quickly slow and move to the free lane. MnDOT says this sudden lane switch can cause backups and road rage.
MnDOT says benefits of employing the zipper merge include reduction in speed differences between lanes, reduction in traffic backup and reduction of freeway interchange congestion.
Merging late and taking turns as the zipper merge dictates means drivers won't be frustrated by passing motorists who are already in the open lane -- drivers ultimately wind up going the same speed as they merge together fairly and seamlessly.
The Star Tribune says the zipper merge will be used:
- On Highway 169 at the Bloomington Ferry Bridge
- Between Crosstown and Highway 7
- At Interstate 694 and Highway 55
Additionally, it will be used on Interstate 35 and Interstate 35E through Lakeville and Eagan as well as on Interstate 494 between Highway 100 and Cedar Avenue.
MnDOT reminds motorists they can merge early instead of the zipper merge when traffic is moving at normal speeds are there are no backups.