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MoDOT recommends drivers merge “like a zipper” in construction zones

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ST. LOUIS (KTVI) - Spring is here and work zones have popped up on nearly every major highway in the St. Louis area. To protect contractors and other workers along these routes, the Missouri Department of Transportation is urging to rethink how they merge into work-zone traffic and “merge like a zipper.”

“It’s called a zipper merge,” said Bill Schnell, MoDOT Assistant District Engineer for St. Louis. “The theory is, instead of trying to get in the lane you want to be in ‘early,’ wait – merge at the last opportunity and each lane takes a turn. That way it doesn’t matter which lane you’re in. Both of them move at the same pace.”

Traffic studies have shown it works amazingly well.

“It’s more efficient. You can actually move 40 percent more traffic if people do that: if they don’t try to get in early or play that game where one car hangs way back,” Schnell said.

And it’s safer. In the past five years, MoDOT reports 61 people have been killed in state and local work zones; more than 4,000 injured, with 16 MoDOT workers killed since the year 2000.

So, please, resist the urge to get over early in moderate or heavy traffic.

“Some people think you should, that that’s the polite thing to do. It actually just backs everything up,” Schnell said. “You should merge at the right location and take turns, just like in grade school, one at a time.”

Transportation departments across the country were recommending this approach, he said.

You'll get plenty of practice in Missouri: I-44 and I-70 alone will have more than a dozen work zones each in Missouri this year.