Change lanes carefully to avoid collisions

​February Law of the Month: Safe Merging

The Wisconsin State Patrol encourages motorists to brush up on their driving fundamentals with the February Law of the Month: Safe Merging. 

Merging includes changing lanes, joining traffic on another road, or entering a roadway from the curb or shoulder. State law requires drivers to stay in their lane and wait to merge until they are certain they have enough space to do so safely.

“Merging is second nature for many drivers. We do this on almost every trip behind the wheel, but it shouldn’t be spontaneous. Each maneuver on the road must be intentional and planned to keep you and others safe on the roads,” State Patrol Superintendent Tim Carnahan said. “Always look before merging and wait for a safe gap in traffic so you won’t cut off other drivers.”

Before changing lanes: 

• Check for traffic to the side and behind your vehicle by using your rear view and side mirrors. Turn and look over your shoulder to check your blind spot before merging. 
• Scan quickly. Do not take your eyes off the road for more than an instant because traffic around you may stop suddenly as you look away.
• Look carefully for other road users like motorcyclists, bicycles and pedestrians who are harder to see than cars and trucks. 
• Use your turn signals. Signaling gives other drivers time to react to your planned move. You must use turn signals before you change lanes, turn right or left, merge into traffic, or park. It’s required by state law.

Merging onto a highway

When merging onto another road, like an interstate or highway, drivers must yield to traffic already moving on the roadway. 

When using an entrance ramp, aim to enter the highway at the same speed that traffic is moving. High-speed roadways generally have an acceleration lane to give you time to build up your speed before you merge into traffic. 

If you have to wait for space to enter a roadway, slow down on the ramp so you have some room to speed up before you have to merge. You must yield to traffic already moving on the roadway.

Zipper merge for lane closures

When traffic patterns change and lanes are closed for construction or emergencies, drivers are asked to use the zipper merge technique to reduce traffic congestion.

When you see a lane closed sign, continue to drive in your lane until you are prompted to merge. When you reach this point, take alternating turns with other drivers to merge into the single lane of traffic.

The zipper merge is a safer way to reduce lanes. When a vehicle slows down to merge early in heavy traffic, it can slow traffic down too quickly, leading to unexpected crashes. The zipper merge allows everyone to move at the same rate, minimizing delays for all.

A zipper merge is not necessary when traffic is moving at highway speeds and there are no backups. Drivers can move over sooner, as long as it is safe to do so.

​Review the Wisconsin Motorists Handbook for more safe driving recommendations and driving requirements. ​

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