Video: The Zipper Merge Is a Snap

CARS.COM — A popular Northern saying is that there are two seasons: winter and construction. But no matter where you travel by car this summer, chances are you’re gonna run into some roadwork requiring lane closures.

And with record numbers of Americans hitting the highways this year, your safety — and sanity will be markedly improved by learning to play nice with the other cars. Perhaps nowhere is the spirit of cooperation among drivers better illustrated than the zipper merge.

Related: As States Fall in Line, Does Zipper Merge Still Push Drivers’ Buttons?

This controversial congestion-control maneuver calls for all drivers in slower-moving traffic ahead of a lane closure to remain in their respective lanes up until the merge point, then take turns moving through the continuing lane, one-by-one, in an orderly fashion coming together like the teeth of a zipper.

Loved by some and loathed by others, the controversial zipper plays right into each individual driver’s sense of fairness with many seeing the drivers who continue in the ending lane up to the last moment as entitled jerks who should’ve gotten over 2 miles back.

But according to studies by federal and state transportation agencies across the country, the maneuver improves traffic flow through a construction zone by as much as 15 percent and reduces the total length of backups by 50 to 75 percent.

Researchers note that everyone moving over into the continuing lane in advance simply doubles the length of that single line of cars while potentially miles of perfectly good asphalt go unused not to mention the brake-tapping-induced slowdown caused by early mergers.

In the growing number of states where the zipper is encouraged, signs instructing drivers to stay in their lane up to the merge point help take the pressure off those in the closing lane maybe sparing them some side-eye, obscene gestures and even drivers playing “lane cop” by straddling the line to block other cars from passing.

But the real keys to keeping traffic flowing through a pinch point are awareness and collaboration with your fellow traveler. Keep in mind that a little cooperation goes a long way, and getting through the zipper … will be a snap.

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Former Assistant Managing Editor-News Matt Schmitz is a veteran Chicago journalist indulging his curiosity for all things auto while helping to inform car shoppers. Email Matt Schmitz

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