Merging and slow zones — Colorado Permit Test

At a zipper merge each car should alternate into the remaining open lane until just before the point of closure, and drivers should continue to drive in both lanes equally when there is a lane closure ahead.

Using both lanes to the end shortens the backup and keeps it moving. Merging early leaves half the road empty and the other half stopped.

Each car should alternate in zipper fashion into the remaining open lane until just before the point of closure

In a zipper merge you should be respectful of those who wait to merge until just before the lane ends, because they are doing it correctly.

The driver who goes to the front is not cutting in. Blocking them is what turns an orderly merge back into a standstill.

In a Zipper Merge, please be respectful of those who wait to merge until just before the lane ends

Slow zones are places where people or traffic gather that require slower speeds and increased attention, such as shopping centers, schools, parks, playgrounds, residential streets, rush hour traffic, narrow bridges, toll plazas and rail crossings.

They have nothing in common except that people are close to the road. That is enough to make every one of them worth slowing for.

Places where people or traffic gather that require slower speeds and increased attention

How should traffic behave approaching a lane closure?

Use both lanes, then take turns at the closure. Using both lanes to the end shortens the backup and keeps it moving. Merging early leaves half the road empty and the other half stopped. Colorado Driver Handbook, p.19: “Each car should alternate in zipper fashion into the remaining open lane until just before the point of closure”