Yes, zipper merging is more efficient than early merging

Zipper merging in construction zones can save drivers time and reduce traffic congestion.

A zipper merge occurs when drivers use both lanes of traffic until reaching a merging point, where motorists then take turns moving into a single lane. Early merging is when motorists move to the open lane as soon as possible before a lane closure.

The Minnesota Department of Transportation said zipper merging can reduce the length of backups by 40% and limit crashes. Another study said congestion can be reduced by up to 50%. Several states have encouraged zipper merging by using signage and public awareness campaigns.

In Sioux Falls, Mayor Paul TenHaken held a news conference June 11, 2025, while wearing a shirt saying, I feel the urge to zipper merge.

For some reason (in South Dakota), its considered rude (to zipper merge), TenHaken said. And its not rude, its very effective, TenHaken said.

Sources

• Minnesota DOT,What is a zipper merge?
• Dakota News Now,TenHaken wants Sioux Falls to feel the urge to zipper merge
• Institute for Transportation Research and Education,ITRE studying how zipper merges reduce congestion at sites across North Carolina

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