Zipper merges are used when a lane is closed ahead due to road construction or maintenance work. Zipper merges are designed to keep traffic moving by allowing drivers to use both lanes until reaching the merge point.
Zipper merges work exactly as they sound – like a zipper!
As drivers see “lane closed ahead” signs, they should stay in their current lane up to the designated merge point. Then drivers should take turns moving into the open lane. This practice is much safer than merging early, which causes congestion and more significant changes in speed.
When a zipper merge is in place, be respectful of other drivers who wait to merge until just before the lane ends – they’re doing it right!