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All this means is that capacity is so far behind demand that current spending doesn't come close to establishing a reasonable equilibrium. Which is what you'd e

All this means is that capacity is so far behind demand that current spending doesn't come close to establishing a reasonable equilibrium. Which is what you'd expect after decades of major population growth, accompanied by infrastructure neglect.

nickles 9y ago
> All this means is that capacity is so far behind demand that current spending doesn't come close to establishing a reasonable equilibrium. I'd hesitate to specify that certain equilibria are reasonable while others are not. Building more roads to reduce congestion does not achieve that goal, in part because of the latent demand you describe (see [0] "Effect in transportation systems"). Ultimately, if your goal is to decrease time spent traveling, you will see more benefit from alternative policies. Such policies may include: * increasing cost of using the roads (e.g. congestion pricing) * constructing alternate, denser forms of public infrastructure (e.g. subways) * increasing the density of passengers in vehicles (buses, carpooling, etc.) * funding technological advances that increase the density of vehicles utilizing the road (e.g. self driving cars) [0] https://en.wikipedia.org/wiki/Induced_demand https://en.wikipedia.org/wiki/Induced_demand
- AmericanChopper 9y ago
  There’s lots of ways to approach defining a ‘reasonable’ equilibrium. You could set a target for average time spent communing, but to address a problem like the one described in the article, you’d just need to build enough freeways to ensure that using a freeway is on average faster than winding through suburban streets. You could do this by decreasing the efficiency of the non-freeway roads, or increasing the cost of using the roads, which both only ‘solve’ the problem by reducing general quality of life (especially for poorer people, who might just get even poorer if they can’t commute affordably). Or you can increase road capacity to keep up with population growth, and invest in alternative transport that people actually want to use. That means no cycle lanes or buses, because people really don’t want to use them (buses are only really efficient for short trips, if you have to change buses to get to work then it ends up taking so long you may as well just be inefficiently sitting in the comfort of your own car).
  - kalleboo 9y ago
    > Or you can increase road capacity to keep up with population growth This doesn't work because in a city you'll eventually you end up with more roads and parking lots than buildings. US cities were built like this, and the more road capacity you build, the more sprawl you get (everything is further apart), which increases how much people have to drive which increases the traffic... It's an evil spiral of congestion.
danmaz74 9y ago
In dense city environments, it's just physically impossible to build enough capacity to meet the potential demand for car rides at peak hours without congestions. You may hate public transportation, but than is the only solution that demonstrably work, together with scooters and yes, even bikes where geography and weather make them viable.
hcurtiss 9y ago
Exactly. I live in a small town. We have no traffic jams, and never have. I believe that proves it’s possible to build sufficient infrastructure to eliminate or reduce traffic jams. It’s just that most large cities elect not to.
- wjnqx 9y ago
  I don't think the cost of that is justified in large cities. LA already dedicates more land area to automobile infrastructure than anything else, and the region is still plagued by traffic jams. At the end of the day, a single rail line can bring an amount of people in and out a city equivalent to multiple lanes of traffic. That's a lesson Americans forgot after 1945 for whatever reason, and now we have to re-learn it from the rest of the world now that we've hit the limits of car-oriented development.
- mantas 9y ago
  Dense large cities are economically unviable if you try to accommodate car traffic. The tale of them being cheaper is true only if you give up large living spaces and personal transport.
- dmoy 9y ago
  Or perhaps for a large enough city, you can't build enough roads, because you'd need like >70% of all area for roads and parking. The scaling doesn't work. For another similar example, think of how much percentsge space you need in a 2 story building devoted to elevators (almost none) vs a 200 story building (a significant percentage of the middle core of the building is nothing but elevators). Take that and scale it even worse, and you have roughly the small town vs big city traffic issue.
- deleted 9y ago
  [deleted]
- quotemstr 9y ago
  Yep. Induced demand is a nuanced concept that's been perverted by a certain community of activists into "science says you can't build enough roads so let's not build any!!!!1111". The truth is that you can, in fact, build enough roads to reduce congestion. It may be too expensive. The road land use fraction may be too high. There may be political problems. All of these factors have to be taken into account before deciding to build more roads. Nevertheless, it is physically possible to build enough roads, and anyone who doesn't acknowledge this basic reality isn't having a serious conversation.

nickles 9y ago

> All this means is that capacity is so far behind demand that current spending doesn't come close to establishing a reasonable equilibrium. I'd hesitate to specify that certain equilibria are reasonable while others are not. Building more roads to reduce congestion does not achieve that goal, in part because of the latent demand you describe (see [0] "Effect in transportation systems"). Ultimately, if your goal is to decrease time spent traveling, you will see more benefit from alternative policies. Such policies may include: * increasing cost of using the roads (e.g. congestion pricing) * constructing alternate, denser forms of public infrastructure (e.g. subways) * increasing the density of passengers in vehicles (buses, carpooling, etc.) * funding technological advances that increase the density of vehicles utilizing the road (e.g. self driving cars) [0] https://en.wikipedia.org/wiki/Induced_demand https://en.wikipedia.org/wiki/Induced_demand

AmericanChopper 9y ago
There’s lots of ways to approach defining a ‘reasonable’ equilibrium. You could set a target for average time spent communing, but to address a problem like the one described in the article, you’d just need to build enough freeways to ensure that using a freeway is on average faster than winding through suburban streets. You could do this by decreasing the efficiency of the non-freeway roads, or increasing the cost of using the roads, which both only ‘solve’ the problem by reducing general quality of life (especially for poorer people, who might just get even poorer if they can’t commute affordably). Or you can increase road capacity to keep up with population growth, and invest in alternative transport that people actually want to use. That means no cycle lanes or buses, because people really don’t want to use them (buses are only really efficient for short trips, if you have to change buses to get to work then it ends up taking so long you may as well just be inefficiently sitting in the comfort of your own car).
- kalleboo 9y ago
  > Or you can increase road capacity to keep up with population growth This doesn't work because in a city you'll eventually you end up with more roads and parking lots than buildings. US cities were built like this, and the more road capacity you build, the more sprawl you get (everything is further apart), which increases how much people have to drive which increases the traffic... It's an evil spiral of congestion.

danmaz74 9y ago

In dense city environments, it's just physically impossible to build enough capacity to meet the potential demand for car rides at peak hours without congestions. You may hate public transportation, but than is the only solution that demonstrably work, together with scooters and yes, even bikes where geography and weather make them viable.

hcurtiss 9y ago

Exactly. I live in a small town. We have no traffic jams, and never have. I believe that proves it’s possible to build sufficient infrastructure to eliminate or reduce traffic jams. It’s just that most large cities elect not to.

wjnqx 9y ago
I don't think the cost of that is justified in large cities. LA already dedicates more land area to automobile infrastructure than anything else, and the region is still plagued by traffic jams. At the end of the day, a single rail line can bring an amount of people in and out a city equivalent to multiple lanes of traffic. That's a lesson Americans forgot after 1945 for whatever reason, and now we have to re-learn it from the rest of the world now that we've hit the limits of car-oriented development.
mantas 9y ago
Dense large cities are economically unviable if you try to accommodate car traffic. The tale of them being cheaper is true only if you give up large living spaces and personal transport.
dmoy 9y ago
Or perhaps for a large enough city, you can't build enough roads, because you'd need like >70% of all area for roads and parking. The scaling doesn't work. For another similar example, think of how much percentsge space you need in a 2 story building devoted to elevators (almost none) vs a 200 story building (a significant percentage of the middle core of the building is nothing but elevators). Take that and scale it even worse, and you have roughly the small town vs big city traffic issue.
deleted 9y ago
[deleted]
quotemstr 9y ago
Yep. Induced demand is a nuanced concept that's been perverted by a certain community of activists into "science says you can't build enough roads so let's not build any!!!!1111". The truth is that you can, in fact, build enough roads to reduce congestion. It may be too expensive. The road land use fraction may be too high. There may be political problems. All of these factors have to be taken into account before deciding to build more roads. Nevertheless, it is physically possible to build enough roads, and anyone who doesn't acknowledge this basic reality isn't having a serious conversation.