Eli5 How are carpool lanes supposed to help traffic? It seems like having another lane open to everyone would make things better?

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I live in Los Angeles, and we have some of the worst traffic in the country. I’ve seen that one reason for carpool lanes is to help traffic congestion, but I don’t understand since it seems traffic could be a lot better if we could all use every lane.

Why do we still use carpool lanes? Wouldn’t it drastically help our traffic to open all lanes?

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Anonymous 0 Comments

I studied this for a paper years ago. The numbers I saw for LA in the 80s there were 1.2 persons per vehicle. If that number went up to 1.4 there would be no congestion. Yes that would mean 17% fewer cars.

If traffic is flowing at 60mph with 1 second between each car 3,600 cars per hour can travel per lane. That is fine until someone wants to change lanes, haha. If your carpool lane requires 3 people per car 1,200 cars will carry as many people. Or if there are 10 buses in that hour even more can travel in that lane.

Traffic monitors have a number of cars per lane they expect for free flowing traffic, once they get beyond that they know things will slow down. How many times have you had to come to a dead stop on the freeway, only to see no evidence of a problem when you finally get back to speed? That is due to PMS. Poor Merging Syndrome.

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