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Yeah it's a known thing now that widening highways / adding more throughput does not ease congestion etc. https://www.nytimes.com/2023/01/06/us/widen-highways-

Yeah it's a known thing now that widening highways / adding more throughput does not ease congestion etc. https://www.nytimes.com/2023/01/06/us/widen-highways-traffic.html#:~:text=But%20while%20adding%20lanes%20can,along%20with%20it%20%E2%80%94%20often%20returns https://www.nytimes.com/2023/01/06/us/widen-highways-traffic....

gotoeleven 3y ago
[flagged]
- InitialLastName 3y ago
  Why is the argument from proponents of road widening always "It will ease congestion" rather than "more people will be able to drive"?
- ebabani 3y ago
  The fuck are you going on about? You think everyone driving is ever going to be sustainable?
  - throwawa14223 3y ago
    Out of curiosity why wouldn't it be? Technology is improving all the time. We'll solve CO2 in the atmosphere and at the point every person on earth will want a green car.
    - Tomis02 3y ago
      There's physically not enough room. It's not a matter of technology.
chrisco255 3y ago
Yes, it really does. Traffic engineering is an entire field of civil engineering. This has been studied for over a century, and the effect of widening highways and increasing speed limits can be simulated mathematically: [1] https://en.wikipedia.org/wiki/Traffic_engineering_(transportation) https://en.wikipedia.org/wiki/Traffic_engineering_(transport... [2] https://www.sciencedirect.com/science/article/abs/pii/S0191261508000180?via%3Dihub https://www.sciencedirect.com/science/article/abs/pii/S01912...
- Kim_Bruning 3y ago
  Right, as can the effect of adding bicycle lanes, smart traffic lights, buses, bus lanes, traffic calming, different road surfaces, and etc etc. And- apparently it gets interesting if you start computing throughput in terms of per person instead of per vehicle.
- getwiththeprog 3y ago
  Here in Sydney, we just got a massive 'size' upgrade and well well, it slowed traffic! https://www.smh.com.au/politics/nsw/the-rozehell-interchange-a-spaghetti-junction-that-doesn-t-pasta-test-20231206-p5epmm.html https://www.smh.com.au/politics/nsw/the-rozehell-interchange... Unfortuantely maths and the real world don't always add up..
- stephen_g 3y ago
  It's the psychology that they don't take into account. Making travel times better in one area makes more people take more trips or change when they take trips, making it worse again until some kind of equilibrium is reached over a year or a couple of years (which is often around the same kind of travel times you had before the upgrade). You could absolutely make traffic better by increasing lanes somewhere where the population was generally decreasing at a decent rate, of course, but population growth is another source in many places - you can't build enough new capacity in a lot of areas to keep up with the growth. The fundamental problem is that cars are a very space inefficient way of moving people - that's why we see this problem in cities but don't tend to see it in rural areas (because they don't have many people but have plenty of space, so the volumetric inefficiency doesn't matter), and why you don't tend to see the issue much with rail other transit - since they have so much passenger capacity for the space they take up, if there's induced demand there's often scope for increasing service frequency.
mdon 3y ago
perhaps the goal isn't eliminating congestion, but allowing more mobility. meaning people can accomplish more things, make more trips.
dex69420 3y ago
Are you proposing the for the first time ever The NY Times printed something factual on January 6, 2023? Or is this more of their bullshit?
- eesmith 3y ago
  The NYT is far from the first to publish on the topic of "induced demand". https://en.wikipedia.org/wiki/Induced_demand https://en.wikipedia.org/wiki/Induced_demand If you don't like them, try any of many other sources. Quoting "If you build it, they will drive: Measuring induced demand for vehicle travel in urban areas" (2018) at https://www.sciencedirect.com/science/article/abs/pii/S0967070X18301720 https://www.sciencedirect.com/science/article/abs/pii/S09670... : > There is little dispute among transportation researchers that expanding highway capacity increases vehicle use. This phenomenon is commonly known as induced demand, and it demonstrates a fundamental economic principle: individuals tend to consume more of a good as the price of the good falls. In other words, wider highways increase traffic speeds and reduce the time cost of driving, thereby inducing additional vehicle travel. In the short run, when residential and employment locations are fixed, faster peak period highway speeds attract drivers from alternate routes, modes, and times of day. Then, in the long-run, faster speeds encourage additional social and economic behavior in areas made more accessible by the new highway capacity, which further increases traffic volumes. > Research studies since the 1960s have suggested that, because of induced demand, the hoped-for benefits from highway expansion tend to be short-lived and do not provide lasting relief to traffic congestion. Early studies by Downs (1962), Smeed (1968), and Thomson (1977) go so far as to argue that, over time and without any other offsetting deterrent, rush-hour traffic speeds tend to revert to their pre-expansion levels. The finding has even been dubbed the Fundamental Law of Road Congestion (Downs, 1962), which asserts that the elasticity of vehicle miles traveled with respect to lane mileage is equal to one, implying that driving increases in exact proportion to highway capacity additions.

gotoeleven 3y ago

[flagged]

InitialLastName 3y ago
Why is the argument from proponents of road widening always "It will ease congestion" rather than "more people will be able to drive"?
ebabani 3y ago
The fuck are you going on about? You think everyone driving is ever going to be sustainable?
- throwawa14223 3y ago
  Out of curiosity why wouldn't it be? Technology is improving all the time. We'll solve CO2 in the atmosphere and at the point every person on earth will want a green car.
  - Tomis02 3y ago
    There's physically not enough room. It's not a matter of technology.

chrisco255 3y ago

Yes, it really does. Traffic engineering is an entire field of civil engineering. This has been studied for over a century, and the effect of widening highways and increasing speed limits can be simulated mathematically: [1] https://en.wikipedia.org/wiki/Traffic_engineering_(transportation) https://en.wikipedia.org/wiki/Traffic_engineering_(transport... [2] https://www.sciencedirect.com/science/article/abs/pii/S0191261508000180?via%3Dihub https://www.sciencedirect.com/science/article/abs/pii/S01912...

Kim_Bruning 3y ago
Right, as can the effect of adding bicycle lanes, smart traffic lights, buses, bus lanes, traffic calming, different road surfaces, and etc etc. And- apparently it gets interesting if you start computing throughput in terms of per person instead of per vehicle.
getwiththeprog 3y ago
Here in Sydney, we just got a massive 'size' upgrade and well well, it slowed traffic! https://www.smh.com.au/politics/nsw/the-rozehell-interchange-a-spaghetti-junction-that-doesn-t-pasta-test-20231206-p5epmm.html https://www.smh.com.au/politics/nsw/the-rozehell-interchange... Unfortuantely maths and the real world don't always add up..
stephen_g 3y ago
It's the psychology that they don't take into account. Making travel times better in one area makes more people take more trips or change when they take trips, making it worse again until some kind of equilibrium is reached over a year or a couple of years (which is often around the same kind of travel times you had before the upgrade). You could absolutely make traffic better by increasing lanes somewhere where the population was generally decreasing at a decent rate, of course, but population growth is another source in many places - you can't build enough new capacity in a lot of areas to keep up with the growth. The fundamental problem is that cars are a very space inefficient way of moving people - that's why we see this problem in cities but don't tend to see it in rural areas (because they don't have many people but have plenty of space, so the volumetric inefficiency doesn't matter), and why you don't tend to see the issue much with rail other transit - since they have so much passenger capacity for the space they take up, if there's induced demand there's often scope for increasing service frequency.

mdon 3y ago

perhaps the goal isn't eliminating congestion, but allowing more mobility. meaning people can accomplish more things, make more trips.

dex69420 3y ago

Are you proposing the for the first time ever The NY Times printed something factual on January 6, 2023? Or is this more of their bullshit?

eesmith 3y ago
The NYT is far from the first to publish on the topic of "induced demand". https://en.wikipedia.org/wiki/Induced_demand https://en.wikipedia.org/wiki/Induced_demand If you don't like them, try any of many other sources. Quoting "If you build it, they will drive: Measuring induced demand for vehicle travel in urban areas" (2018) at https://www.sciencedirect.com/science/article/abs/pii/S0967070X18301720 https://www.sciencedirect.com/science/article/abs/pii/S09670... : > There is little dispute among transportation researchers that expanding highway capacity increases vehicle use. This phenomenon is commonly known as induced demand, and it demonstrates a fundamental economic principle: individuals tend to consume more of a good as the price of the good falls. In other words, wider highways increase traffic speeds and reduce the time cost of driving, thereby inducing additional vehicle travel. In the short run, when residential and employment locations are fixed, faster peak period highway speeds attract drivers from alternate routes, modes, and times of day. Then, in the long-run, faster speeds encourage additional social and economic behavior in areas made more accessible by the new highway capacity, which further increases traffic volumes. > Research studies since the 1960s have suggested that, because of induced demand, the hoped-for benefits from highway expansion tend to be short-lived and do not provide lasting relief to traffic congestion. Early studies by Downs (1962), Smeed (1968), and Thomson (1977) go so far as to argue that, over time and without any other offsetting deterrent, rush-hour traffic speeds tend to revert to their pre-expansion levels. The finding has even been dubbed the Fundamental Law of Road Congestion (Downs, 1962), which asserts that the elasticity of vehicle miles traveled with respect to lane mileage is equal to one, implying that driving increases in exact proportion to highway capacity additions.