eli5: would adding more lanes to a freeway/busy street really ease congestion or would you still get bottlenecks?

Question

I mean theoretically adding a lane or two should allow more cars to flow through, or would bad drivers still cause bottlenecks/gridlock despite the added capacity?

In: 28

Answer 1

There’s a thing called induced demand. If you build more lanes, you won’t get less congestion, you’ll just get more people driving, using up the extra capacity and causing the same amount of congestion.

That why LA can have 8 lane highways and still get traffic jams just like a city with much smaller highways.