It’s generally accepted that more lanes does not equal less traffic, and can often lead to the opposite effect due to the effect of induced demand [1]. I personally believe providing multiple alternative transport options is more effective but obviously that’s a matter of opinion...
Serious question but is there a reason more isn't invested in public transport? I've only ever lived in the UK before Tokyo but America is rich enough I don't see why they can't do what those places do.
The major reason seems to be a lack of cultural support. Despite everything, people still largely dislike the idea of public transit. I read a very good article that said to generate interest, transit must preemptively provide better service... its a catch 22
Simple: sprawl and ultra low density. Public transport thrives in areas where a single bus stop serves hundreds or more of people, but in rural areas it's cost-prohibitive.
The implicit context of this argument is that space is limited and we can't indefinitely expand roads. We almost certainly can indefinitely lay more fiber.
That said, the logic does apply to wireless spectrum, which is a limited resource. If we allocate enough spectrum that people can replace wired connections, there will definitely be significant and unsustainable demand for even more bands.
Am I the only one that finds that using that theory to justify not adding capacity is utterly idiotic?
If you add capacity and it ends up being all used up, it just means you didn't add enough and should add even more if possible!
Kind of like saying that in a famine it's useless to provide more food because it's going to be eaten all up anyway since some people are no longer dying of famine...
There's definitely a balance to be struck (you can't just build lane after lane after lane and expect linear improvement) but yeah, not adding capacity because the capacity will be used is just asinine. It's just something about personally owned vehicles that makes people dumb. Most of those same people wouldn't complain about people using the new capacity if the discussion was about extending bus routes or making subways run more frequently.
No, this canard gets raised in every traffic thread. The real reason why “induced demand” exists is because roads in urban areas are usually so under built that any reasonably good road is crushed by extra users once it is built. If governments actually kept sufficient roads available then there would not be induced demand.
Alternatively, the government should charge all road users a sufficiently high toll to keep the roads moving.
The fact that some growth has happened despite a lack of road-building does not disprove that more growth could have happened if more roads were built.
> it just means you didn't add enough and should add even more if possible!
houston has 16 lane highways and still has traffic. The population density of cities is simply too high to have cars be the primary form of transportation.
This canard is also used to justify taking taxes meant for road improvement and spending them on dubious public transport schemes. For some reason they are rarely invested in well run commuter buses, for instance.
Traffic doesn’t work like that. You seem to have a mental model where traffic is modeled like a liquid (traffic has a definite volume and does not expand to fill its container) while many studies show traffic behaves more like a gas (traffic expands to fill its container). Basically, more lanes doesn’t mean less traffic, it generally means the same amount of traffic.
