[bwhiting2356]

Adding lanes may not cut congestion in the long term, but it can increase throughput and overall utility by moving more people and goods.

[array_key_first]

Each additional lane has less and less impact because of lane switching. Ultimately, you can still only enter or exit on the left or right, regardless of if you have 100 lanes. And having people move across 100 lanes to exit is much slower than moving across one or two.

[ronbenton]

I don't doubt it. It is quite a while ago so I don't fully recall the talk that my professor gave, but I don't believe he intended to mean adding lanes was useless, just that they didn't help with congestion of the particular roadway

[bluGill]

If adding lanes doesn't help you didn't add enough. People live in a city to do things and you need to enable that by preventing congestion.

i don't know how to afford the 50 more lanes that most cities need though. I suggest better transit.

[CarVac]

Road throughput doesn't solve congestion when road throughput isn't the issue.

They are trying to widen the NJ Turnpike but the congestion isn't because 6 lanes aren't enough, the congestion is because the three Hudson crossings into Manhattan cannot ingest 6 lanes worth of traffic.

[simonra]

Look up «Braess's paradox», more throughput when removing capacity is long established (century +) in systems with simplistic greedy agents like humans

[ronbenton]

how do you see that something is downvoted? I don't see points on any comments but my own