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It's a great channel that puts words to just why American cities are so dystopic. It really helps understand exactly what "induced demand" means. If you add an

It's a great channel that puts words to just why American cities are so dystopic. It really helps understand exactly what "induced demand" means. If you add another lane, some of the people on the bus will take the car, and thus the new lane is almost immediately full again. If you remove the bus lane, bike lane, sidewalk, same thing. Adding capacity for cars actually makes travelling by car worse. It also gives hope. Like just because a city was destroyed to make it more car centric doesn't mean it can't be fixed to be livable again. There's more to strongtowns than this, but it's all interesting.

bluGill 5y ago
Induced demand is nonsense. If people leave the bus to drive it indicates your bus system is providing bad service. If more people drive it indicates that your city isn't filling its purpose as being a place where there are a lot of things to do. Cities need to figure out how to get ahead of induced demand not how use it as an excuse to be a worse city.. sure, this is a hard problem, with many options that make something else work, but induced demand is still a terrible excuse to be a bad city.
- knorker 5y ago
  Induced demand is not nonsense at all. I don't have a car. If there were capacity to drive, I would. If a bunch of capacity to drive was added, I'd buy a car. So that's one data point. > If more people drive it indicates that your city isn't filling its purpose as being a place where there are a lot of things to do. This sounds like an argument from someone who's never heard any alternative to American status quo. > Cities need to figure out how to get ahead of induced demand Wait, you said it's nonsense? I'm starting to think you're misunderstanding me. Induced demand is not an excuse, it's an antipattern no be avoided, and it's not irreversible. It's about how adding lanes to a road doesn't help traffic (see Katy, Texas). Or the I101. Adding a lane, or improving the Caltrain? Clearly the latter will improve 101 traffic more.
  - bluGill 5y ago
    At no point did I say what the solution was. You incorrectly assumed I'm advocating more lanes of traffic, that is one possible solution - if you do it be prepared to go up (or down), as you will need many layers of layers over layers (bridges) that way. There are many other possible solutions though. It didn't work in Katy Texas because they didn't build enough. Improving transit would be my preferred option. The point is if adding a lane of anything doesn't solve your traffic problem (or makes it worse) then you are not thinking big enough.
    - knorker 5y ago
      You did say "Induced demand is nonsense". And it's not. > It didn't work in Katy Texas because they didn't build enough. The Katy Freeway is literally the widest highway in the world. The biggest in the world. Adding lanes doesn't help. This is not controversial. > Improving transit would be my preferred option. There are many solutions, and you don't have to pick just one. Better transit. Dedicated bus lanes. Mixed zoning (so much this). Separate bike lanes. Etc.. etc.. It's not that we should force people to use the bus. It's that if you're stuck in traffic and had a magic wand that could turn 30 cars into one bus, would you use it? Well, clearly yes. Many times. Ok, so now that this driver agrees that they want other people to use the bus, it's just a matter of making the bus experience better, so that they do. But yes, that falls under (as you say) "improving transit". But there's more. Anyway, "Not Just Bikes" says this so much better than I could.
- occz 5y ago
  >Induced demand is nonsense. It's been shown to be real in studies upon studies - what are you trying to say here?
  - bluGill 5y ago
    Sure it has been shown: because people have places they would like to get to that the city is making too difficult for them. It clearly exists, it is just a stupid excuse.
    - knorker 5y ago
      Adding lanes has been shown (as you agree) to not help the people who want to use the road, as is just induces more demand. So how is it an excuse? If spending billions on new lanes doesn't actually help anyone, that's just government waste.
      - bluGill 5y ago
        > Adding lanes has been shown (as you agree) to not help the people who want to use the road, as is just induces more demand. Only when you don't add enough lanes. It hurts some people who are already using the existing lanes, but it helps other people who previously found the trip so painful they didn't take make it at all, but now the level of pain is low enough that they make it. Focusing only on those who are already using the road isn't the answer, we need to focus on everyone.
        emodendroket 5y ago
        I think the point here is it's not practical to build enough lanes to ever saturate demand someplace like LA, so it would make sense to build other options besides driving your car everywhere (and then make these options more attractive than driving). These will of course induce demand of their own, but it's easier to meet just because each person traveling in his own car is one of the least space-efficient means of getting around imaginable. That's not necessarily a big deal in the middle of the day, but at rush hour, with countless people heading in the same direction, it doesn't necessarily make sense to keep doubling down on the same strategy over and over.
- LeChuck 5y ago
  I agree with you. I think people are downvoting you because they misunderstand your first sentence. Using the concept of induced demand to justify building fewer roads is bullshit, if you don't figure out why there's so much pent up demand to begin with. The way forward should be making all the alternatives more attractive, so that the demand for cars disappears.
  - xorfish 5y ago
    To avoid induced demand, you need to make other modes of transport more attractive than driving. So if there are two routes from A to B and one is longer, then the shorter route should be reserved for the modes of transports that have a higher capacity. (That usually means banning cars) Another really good option is to have dedicated bus lanes so buses don't get stuck in traffic. As a car driver you massively benefit if other people take the bus or bikes instead of their car. Plus you and especially the ones who are to old, young, poor, disabled to drive a car have good options of getting around.
  - knorker 5y ago
    > Using the concept of induced demand to justify building fewer roads is bullshit Well, you don't have infinite money, or space. Adding a bus lane and a car lane clearly will add more capacity than doing just one of them, but adding a bus lane will likely reduce traffic so much in the other lanes that you don't even have to add another car lane. And adding just a car lane means people would rather be stuck in their car, than stuck in the bus, in the same lane, and we have tragedy of the commons. So adding a car lane just means emptier busses, but same slow traffic. So what value did adding the lane add? It'd just be government waste.
    - bluGill 5y ago
      > Adding a bus lane and a car lane clearly will add more capacity than doing just one of them, but adding a bus lane will likely reduce traffic so much in the other lanes that you don't even have to add another car lane. The first is true, but the second doesn't follow. For a bus lane to make a difference you need more than a lane, you also need good bus service using that lane. Bus service in many cities horrible and so nobody sane will ride it. A lane of empty buses running around helps nothing. If you propose a bus lane you need to do it with all the service that will happen so we can evaluate it.
- throwawaysea 5y ago
  I agree that induced demand is nonsense, but for a different reason. Demand either exists or it doesn't. It is either fulfilled or unfulfilled. Building more lanes into a road doesn't "induce" demand. It fulfills it. People use up that road space because they genuinely get a benefit from it. It's really that simple. After all, if you built 100 lanes there wouldn't magically be 100 lanes of traffic. Demand is fulfilled only up to the point that the demand exists. There's no magical induction that urbanists vaguely gesture at.
  - knorker 5y ago
    > I agree that induced demand is nonsense It's not. This is a fact. It sounds like you are trying to reason about this from pure logic, and are not aware that this is an empirical fact. You can only go so far armchair guessing about how city planning "ought to" work. > Demand either exists or it doesn't. To get to the place, yes. To get to the place in a car, no. If you double the capacity of a road network, that means more people will choose to drive. Example: If the city I live in doubled the car capacity, I would buy a car and drive it. But since everyone else would too, it'd actually stabilize to the same congestion. (I forget, but the actually observed phenomenon has a name) Or let's say you had some billions of dollars to improve the situation of the I-101 in California. What do you think will happen if you add a lane? More people who currently take a tech company shuttle will start driving instead. More people who currently take Caltrain will start driving instead. And then you're back. I'm not guessing, this is established knowledge. No matter how hard people try to double down on a failed strategy (see Katy Freeway), it just doesn't help traffic. It just makes more people drive. Now spend those billions on making the Caltrain experience better, and you'll start seeing existing lanes on the 101 free up. > After all, if you built 100 lanes there wouldn't magically be 100 lanes of traffic. A 100? Maybe not. But apparently 26 lanes is not enough (Katy Freeway). But there are other aspects to this too, other than roads and transit. E.g. zoning. It greatly reduces traffic on existing roads if you can just walk over to the store to buy some groceries, because it's a 5min walk. Instead of driving and being stuck in traffic for 10 minutes because it's too far to walk and crosses an 8 lane highway. Every person who went shopping in the local store is another car not on the road, both ways. > Demand is fulfilled only up to the point that the demand exists. This is only true in the sense that it's irrelevant. If you widen every street and avenue in NYC to 26 lanes, then maybe that's enough. But only because there will barely be any houses left to go to. > There's no magical induction that urbanists vaguely gesture at. That's not what's happening.

bluGill 5y ago

Induced demand is nonsense. If people leave the bus to drive it indicates your bus system is providing bad service. If more people drive it indicates that your city isn't filling its purpose as being a place where there are a lot of things to do. Cities need to figure out how to get ahead of induced demand not how use it as an excuse to be a worse city.. sure, this is a hard problem, with many options that make something else work, but induced demand is still a terrible excuse to be a bad city.

knorker 5y ago
Induced demand is not nonsense at all. I don't have a car. If there were capacity to drive, I would. If a bunch of capacity to drive was added, I'd buy a car. So that's one data point. > If more people drive it indicates that your city isn't filling its purpose as being a place where there are a lot of things to do. This sounds like an argument from someone who's never heard any alternative to American status quo. > Cities need to figure out how to get ahead of induced demand Wait, you said it's nonsense? I'm starting to think you're misunderstanding me. Induced demand is not an excuse, it's an antipattern no be avoided, and it's not irreversible. It's about how adding lanes to a road doesn't help traffic (see Katy, Texas). Or the I101. Adding a lane, or improving the Caltrain? Clearly the latter will improve 101 traffic more.
- bluGill 5y ago
  At no point did I say what the solution was. You incorrectly assumed I'm advocating more lanes of traffic, that is one possible solution - if you do it be prepared to go up (or down), as you will need many layers of layers over layers (bridges) that way. There are many other possible solutions though. It didn't work in Katy Texas because they didn't build enough. Improving transit would be my preferred option. The point is if adding a lane of anything doesn't solve your traffic problem (or makes it worse) then you are not thinking big enough.
  - knorker 5y ago
    You did say "Induced demand is nonsense". And it's not. > It didn't work in Katy Texas because they didn't build enough. The Katy Freeway is literally the widest highway in the world. The biggest in the world. Adding lanes doesn't help. This is not controversial. > Improving transit would be my preferred option. There are many solutions, and you don't have to pick just one. Better transit. Dedicated bus lanes. Mixed zoning (so much this). Separate bike lanes. Etc.. etc.. It's not that we should force people to use the bus. It's that if you're stuck in traffic and had a magic wand that could turn 30 cars into one bus, would you use it? Well, clearly yes. Many times. Ok, so now that this driver agrees that they want other people to use the bus, it's just a matter of making the bus experience better, so that they do. But yes, that falls under (as you say) "improving transit". But there's more. Anyway, "Not Just Bikes" says this so much better than I could.
occz 5y ago
>Induced demand is nonsense. It's been shown to be real in studies upon studies - what are you trying to say here?
- bluGill 5y ago
  Sure it has been shown: because people have places they would like to get to that the city is making too difficult for them. It clearly exists, it is just a stupid excuse.
  - knorker 5y ago
    Adding lanes has been shown (as you agree) to not help the people who want to use the road, as is just induces more demand. So how is it an excuse? If spending billions on new lanes doesn't actually help anyone, that's just government waste.
    - bluGill 5y ago
      > Adding lanes has been shown (as you agree) to not help the people who want to use the road, as is just induces more demand. Only when you don't add enough lanes. It hurts some people who are already using the existing lanes, but it helps other people who previously found the trip so painful they didn't take make it at all, but now the level of pain is low enough that they make it. Focusing only on those who are already using the road isn't the answer, we need to focus on everyone.
      - emodendroket 5y ago
        I think the point here is it's not practical to build enough lanes to ever saturate demand someplace like LA, so it would make sense to build other options besides driving your car everywhere (and then make these options more attractive than driving). These will of course induce demand of their own, but it's easier to meet just because each person traveling in his own car is one of the least space-efficient means of getting around imaginable. That's not necessarily a big deal in the middle of the day, but at rush hour, with countless people heading in the same direction, it doesn't necessarily make sense to keep doubling down on the same strategy over and over.
LeChuck 5y ago
I agree with you. I think people are downvoting you because they misunderstand your first sentence. Using the concept of induced demand to justify building fewer roads is bullshit, if you don't figure out why there's so much pent up demand to begin with. The way forward should be making all the alternatives more attractive, so that the demand for cars disappears.
- xorfish 5y ago
  To avoid induced demand, you need to make other modes of transport more attractive than driving. So if there are two routes from A to B and one is longer, then the shorter route should be reserved for the modes of transports that have a higher capacity. (That usually means banning cars) Another really good option is to have dedicated bus lanes so buses don't get stuck in traffic. As a car driver you massively benefit if other people take the bus or bikes instead of their car. Plus you and especially the ones who are to old, young, poor, disabled to drive a car have good options of getting around.
- knorker 5y ago
  > Using the concept of induced demand to justify building fewer roads is bullshit Well, you don't have infinite money, or space. Adding a bus lane and a car lane clearly will add more capacity than doing just one of them, but adding a bus lane will likely reduce traffic so much in the other lanes that you don't even have to add another car lane. And adding just a car lane means people would rather be stuck in their car, than stuck in the bus, in the same lane, and we have tragedy of the commons. So adding a car lane just means emptier busses, but same slow traffic. So what value did adding the lane add? It'd just be government waste.
  - bluGill 5y ago
    > Adding a bus lane and a car lane clearly will add more capacity than doing just one of them, but adding a bus lane will likely reduce traffic so much in the other lanes that you don't even have to add another car lane. The first is true, but the second doesn't follow. For a bus lane to make a difference you need more than a lane, you also need good bus service using that lane. Bus service in many cities horrible and so nobody sane will ride it. A lane of empty buses running around helps nothing. If you propose a bus lane you need to do it with all the service that will happen so we can evaluate it.
throwawaysea 5y ago
I agree that induced demand is nonsense, but for a different reason. Demand either exists or it doesn't. It is either fulfilled or unfulfilled. Building more lanes into a road doesn't "induce" demand. It fulfills it. People use up that road space because they genuinely get a benefit from it. It's really that simple. After all, if you built 100 lanes there wouldn't magically be 100 lanes of traffic. Demand is fulfilled only up to the point that the demand exists. There's no magical induction that urbanists vaguely gesture at.
- knorker 5y ago
  > I agree that induced demand is nonsense It's not. This is a fact. It sounds like you are trying to reason about this from pure logic, and are not aware that this is an empirical fact. You can only go so far armchair guessing about how city planning "ought to" work. > Demand either exists or it doesn't. To get to the place, yes. To get to the place in a car, no. If you double the capacity of a road network, that means more people will choose to drive. Example: If the city I live in doubled the car capacity, I would buy a car and drive it. But since everyone else would too, it'd actually stabilize to the same congestion. (I forget, but the actually observed phenomenon has a name) Or let's say you had some billions of dollars to improve the situation of the I-101 in California. What do you think will happen if you add a lane? More people who currently take a tech company shuttle will start driving instead. More people who currently take Caltrain will start driving instead. And then you're back. I'm not guessing, this is established knowledge. No matter how hard people try to double down on a failed strategy (see Katy Freeway), it just doesn't help traffic. It just makes more people drive. Now spend those billions on making the Caltrain experience better, and you'll start seeing existing lanes on the 101 free up. > After all, if you built 100 lanes there wouldn't magically be 100 lanes of traffic. A 100? Maybe not. But apparently 26 lanes is not enough (Katy Freeway). But there are other aspects to this too, other than roads and transit. E.g. zoning. It greatly reduces traffic on existing roads if you can just walk over to the store to buy some groceries, because it's a 5min walk. Instead of driving and being stuck in traffic for 10 minutes because it's too far to walk and crosses an 8 lane highway. Every person who went shopping in the local store is another car not on the road, both ways. > Demand is fulfilled only up to the point that the demand exists. This is only true in the sense that it's irrelevant. If you widen every street and avenue in NYC to 26 lanes, then maybe that's enough. But only because there will barely be any houses left to go to. > There's no magical induction that urbanists vaguely gesture at. That's not what's happening.