Traffic Q&A: Merging early may be nice, but it’s not always best for traffic

Question: I’ve stopped trying to convince my brother-in-law what the best thing to do is when a freeway narrows and the right lane ends. We have two completely different schools of thought.

When I see a sign that says “Lane Ends Ahead” – like on eastbound Highway 16 at Union Avenue – I move to the left fairly quickly and, yes, I often end up waiting my turn in a line of other patient souls.

He’s one of the jerks who stay in the right lane as long as possible, speeding past all the waiting cars and merging left at the last possible minute. He saves maybe a minute and makes a hundred people mad.

He says he’s not bothered by all the people who flip him off because the road is designed for that and it’s more efficient. He says I’m a sucker for waiting in line like an idiot.

Who’s right?

– William, University Place

Answer: You might not like this.

Rude as it may seem, your brother-in-law may have a point, at least when traffic is heavy.

Ray Crumbley, a traffic design engineer at the state Department of Transportation, says that, from a pure engineering point of view, the overall efficiency of the merge in situations like the one you describe depends on the volume of traffic and how traffic is flowing.

According to Crumbley, studies show that if traffic is light and free flowing, traffic moves better if people begin merging at the point where they first see the “Land Ends Ahead” sign – the way you do it, in other words.

However, if the freeway is crowded, he says traffic moves better overall if people fill both lanes and then zipper at the end where the merge is, taking turns.

If it’s any consolation, you’re not alone in your reaction.

“People’s merging behaviors are a source of great frustration for drivers in general,” said Claudia Bingham Baker, communications manager in WSDOT’s Olympic Region.

“People are passionate about this,” she said “They call; they write. They want us to change the merge point, but at some point you still have to merge. If we moved it, we would still have the problem; it would just be in a different place.”