SEATTLE'S MORNING NEWS

How to zipper merge properly? ‘I-5 commuters’ share dos and don’ts

May 23, 2025, 5:01 AM | Updated: 7:07 am

Charlie Harger, co-host of “Seattle’s Morning News” on KIRO Newsradio, dug into the correct use of a zipper merge and the daily territorial war for drivers with the “I-5 commuters” Joe and Craig.

“If it’s a checkered line, zipper merge all you want, but you won’t talk me out of a double white line,” Joe said.

The zipper merge—when two or more cars on the roadway take turns converging into the same lane, likely due to a blockage—has become one of the most debated topics in traffic.

Harger mentioned his strategy on Washington roads.

“My policy is that I will let one person in front of me if I am in the line, and then after that, nobody else is getting in,” Harger said.

I-5 commuters talk zipper merge in basketball terms

Harger summed it up as a lack of understanding, rather than incompetence.

“Why don’t people (zipper merge)? I don’t understand. Do we not teach how to merge?” Harger said. “I think that’s one of the big issues. People think you’re cheating, and you’re cutting the line. No, it cuts down on the congestion, and it’s safer.”

Joe linked the battle for a spot in traffic to playing defense on a basketball court, with a playful homage to a former Seattle Supersonic.

“Sometimes it’s Craig, and sometimes it’s Gary Payton in the driver’s seat, playing some good defense, and not letting people in,” Joe said.

KIRO Newsradio traffic reporter gives his thoughts

KIRO Newsradio’s traffic reporter, Chris “Sully” Sullivan, chimed in and offered his opinion on the matter.

“A double white line is illegal. You cannot cross that,” Sully said. “If we got some signage, indicating that this is a zipper merge area, by all means, get in the lane. Let’s be a team out here.”

Listen to “Seattle’s Morning News” with Charlie Harger and Manda Factor weekday mornings from 5-9 a.m. on KIRO Newsradio. Subscribe to the podcast here.

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