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>> I believe the argument would be that not creating induced demand will provide market effects to encourage the use of transit Induced demand is a concept tha

>> I believe the argument would be that not creating induced demand will provide market effects to encourage the use of transit Induced demand is a concept that anti-car people use, but I don't think it makes much sense. Imagine a library that only has a few copies of some best selling children's books. There's a very long queue to check out those books. Someone might argue that, "We should buy more copies of the best selling children's books". The induced demand argument in this case would be: "If we buy more copies of those books, the queue wont disappear, since it is so long, but also, if the queue gets shorter, we might have people who don't use the library because of the queue start using it. We would be no better off!". Of course in this analogy, we realize the fallacy. People are better off because more kids get to read books. Even if the queue stays the same length, we have more throughput, more kids get the benefit. Now if we translate that to cars, of course, we see the difference. People who write books like "Paved Paradise" or "The High Cost of Free Parking" hate cars. They really do. They hate the suburbs too. So when they see something that would enable people who don't currently drive cars to drive cars, or for people who live in urban areas to live in suburban areas, they're of course going to be against that. "Induced demand" is being used here by languagehacker, as it is used by other people who are opposed to private property, as some sort of technical term that supports their case. But that isn't true. By adding more copies of popular books to libraries, we want to induce demand. We want people to read the books, and we want people who don't currently use libraries to consider using them. The induced demand is not bad. We had a queue, it was too long, we shorten the queue, and by doing so some people who thought the queue was too long will no longer think that. This is good. What languagehacker is saying, by referring to induced demand, is that, in the opinion of languagehacker cars are bad. It is as simple as that. It sounds super-scientific when you use terms like "induced demand", but it is not, in fact, super-scientific. It's just a value judgement. To me, if you build a highway in an area that has high traffic congestion, and after you build the highway, it still has high traffic congestion, it means more people are getting where they want to be. It's called "induced demand". Induced demand is good. We should have more of it.

hammock 2y ago
> The induced demand argument in this case would be: "If we buy more copies of those books, the queue wont disappear, since it is so long, but also, if the queue gets shorter, we might have people who don't use the library because of the queue start using it. We would be no better off!". https://en.wikipedia.org/wiki/Jevons_paradox# https://en.wikipedia.org/wiki/Jevons_paradox#
tromp 2y ago
Except that having more car traffic induces more pollution, more casualties, and more time spent unproductively (you can do other things on public transit, or get exercise commuting by bike), whereas more book reading has few downsides.
- rufus_foreman 2y ago
  >> you can do other things on public transit, What can I do on public transit that people don't do in a car in traffic?
  - Jensson 2y ago
    Browse your phone? Everyone does that in public transit, drivers don't do that in cars. You could read HN and post messages for example.
    - tekla 2y ago
      > drivers don't do that in cars See the problem is that they do, right before they drive into a pedestrian or stationary object.
  - basil-rash 2y ago
    Get harassed by homeless? Or just men in general, if you’re a remotely attractive female (using the broadest term available as it certianly isn’t restricted to what we’d appropriately call “women”).
    - Jensson 2y ago
      Do you think public transit is full of drunkards? Its mostly tired people getting to or from work, those doesn't harass a lot of people. When its late and its a lot of drunks on public transit sure, but not on normal commutes. Columns I've read from women getting harassed its mostly about dance floors at clubs, not commute trains, when people aren't drunk they mostly keep their hands to themselves.
currymj 2y ago
i think the point of "induced demand" is that you sometimes can't really fix -- specifically -- traffic or parking congestion problems by building more. if you widen the roads, in many cases it won't make your commute any quicker. if you add more parking spots downtown, more people will drive downtown. it's not that there's no benefit to the wider road or parking spots, just that the benefit people really care about -- less traffic and quicker trips, less time searching for a parking spot -- often fails to materialize.
- rufus_foreman 2y ago
  >> if you add more parking spots downtown, more people will drive downtown But that's good if you wan't more people to drive downtown, isn't it? What am I missing here?
  - Jensson 2y ago
    > What am I missing here? That downtown is now a concrete hellscape instead of a pleasant place to be. Your solution ensures that always happens, overall people prefer less infrastructure built for cars, but if it is there of course they will use it.
    - HDThoreaun 2y ago
      This just isnt true. Every metro area in the US has highways. Including the dense ones. NYC and Chicago are not concrete hellscapes
      - Jensson 2y ago
        You say NYC and Chicago has enough highways to fill demand so there is no congestion? I am fairly certain that isn't true, I've read so much about congestion problems in NYC at least. Adding enough roads to fill all demand leads to concrete hellscapes, that was the point, the guy I responded to thought it was reasonable to add roads until all demand was satisfied.
thefaux 2y ago
This is a flawed analogy and I think there is a false dichotomy by framing skepticism around building more highways as inherently anti-car. I'm going to go out on a limb and say most drivers do not enjoy traffic and most residents near busy roadways do not enjoy the effects of traffic on their neighborhood. The question is what is the best policy approach that manages all people's concerns. For me, the question is how can we get people to live and work in areas where it isn't necessary to inefficiently, and very expensively, move people to and from work. Since the 1950s, we have optimized for essentially the least efficient form of transit available. It seems completely bonkers to me that in the bay and other high density areas, you have many, many workers, particularly at the low end of the income scale, driving over an hour each way to work. It is an understandable and rational decision for the driver, but crazy to me for society.
- cebert 2y ago
  > For me, the question is how can we get people to live and work in areas where it isn't necessary to inefficiently, and very expensively, move people to and from work. I cannot comprehend why more firms aren’t embracing remote work more than they do. It helps alleviate a lot of these traffic challenges and can result in reduced carbon footprints as well as more happy employees. I hope we start considering remote work as a solution to some of these problems more in the future.
- deleted 2y ago
  [deleted]
- throwaway2037 2y ago
  Yeah, I agree. Most built up areas in California are horribly planned!
lkurtz 2y ago
I don’t think this analogy is quite correct. Driving on a particular route is not a driver’s objective like reading a particular book is a reader’s objective. The driver’s objective is arriving at a destination. The objective in driving is not a finite resource, but the multiple route options to the objective can be, which differs substantially from a library queue.
- thereisnospork 2y ago
  Let's consider a library with both a manned librarian and a self checkout, two different queues, same objective. Let's call the self checkout the 'highway' queue and the manned one the 'surface street' queue. Each of which could be expanded to improve throughput (more lanes:more self checkout lanes, more streets:more librarians). Ultimately the problem with anti-car rhetoric is that it seeks to limit access to the objective because it is "wrong" to use a self checkout lane and people must be forced to check books out in the morally correct manner. No one (reasonable) has a problem with the library adopting a mobile checkout app, which let's call mass transit. But crippling self checkout to force adoption of the mobile checkout app could be at best described as a 'dark pattern', forcing people to check out books 'the right way' at the cost of overall readership.
  - troupo 2y ago
    The people who freely use terms like "anti-car" always assume that the car is always the fastest most efficient way of getting anywhere... and then sit stuck in standstill on a 6-10-lane highway
    - fragmede 2y ago
      don't forget driving around looking for parking for 20 mins as well
  - lkurtz 2y ago
    In your example, replacing bulky self-checkout machines (analogous to removing road/surface parking real estate) offers a significant benefit to everyone. More room for what everyone actually wants most: books. The preference for self-checkout machines forces a cost on everyone for the benefit of a few.
tidbits 2y ago
Books are not a finite resource? Obviously there is a finite number of trees but there are enough for it not to be a bottleneck. Land on the hand is a finite resource, especially in large, urban cities. There is no way to design a highway or other car infrastructure that will meet the demands of any reasonably sized city without dedicating an unreasonable amount of land to cars. Anyway, Ray explains it better than I could and he agrees that the term is bad: https://youtu.be/za56H2BGamQ https://youtu.be/za56H2BGamQ
ksplicer 2y ago
What you are missing is that every time we widen roads to allow more car throughput we are making every other type of transit and mobility less attractive. Busy streets with big parking lots are unpleasant to walk or bike along, so people just drive to their destinations instead, which makes the street even busier, louder, and smellier starts this cycle all over again. Every time a road is widened or a new parking lot is added the city also becomes less dense, making getting anywhere useful more time consuming. Drivers have to spend longer on the road to get where they want to go, public transit gets more expensive as routes get longer, and walking and biking quickly become too time consuming. There is just a maximum density that cars can support which works totally fine for suburbs but breaks down in denser cities. Personally I think Park and Ride programs are the most reasonable compromise.
- kjkjadksj 2y ago
  People always seem to forget the bus takes advantage of having multiple travel lanes and faster intersection clearance too. City of LA is starting to take advantage of their wide roads and put in bus only lanes, something they could easily do with some paint since the pavement already exists.
  - ksplicer 2y ago
    You don't need more than two lanes to dedicate one to buses.
seadan83 2y ago
Perhaps a library vs a commercial book store might have worked as a better analogy. The queue theory part of it I think breaks down a lot. Induced demand is not only about queue theory, but also choosing between options. In short though, induced demand is somewhat simple. If it takes 10 minutes to drive and 30 minutes to take a bus, then I drive. If it takes 30 minutes to drive and 10 minutes to take a bus, then I take the bus. Eventually enough people choose to drive, or take a bus, that that mode becomes congested/inconvenient enough that people start making other choices. In other words, there are some people who avoid highways during rush hour because the traffic jams are bad. If the highway is widened, then they would join the rush hour once again and be part of the traffic jams. Induced demand is about taking away the reason why people avoid something, and thereby doing so they change their behavior to start doing that thing.
- HDThoreaun 2y ago
  Yea but really the choice here is "go somewhere vs stay home", not "car vs bus". Highway expansion leads to more people travelling because bus service is non existent in the vast majority of the country. Of course some people need to go where theyre going, but on the margins more people will go to the city or what not if traffic is lower.
  - seadan83 2y ago
    Good points. Yeah, as the cost of travel goes up, people make various decisions: bite-the-bullet, find alternatives, delay, consolidate, and/or go without. As the cost decreases, the incentives to find alternatives, delay or consolidate trips goes down (which means roads are then used for less important reasons and less efficiently - why go to the grocery store once a week if you can go every day in half the travel time?) I would agree, at some point when all alternatives are equally unattractive (or non-existent), then going without is a more attractive option. Though, the "consolidate" option is a big one to consider. Rather than going to the city every day, perhaps people could do so every other day for the same benefit. If traffic is bad, then people will go less often (frequency of travel is a function of cost). Thus, in some cases, highway expansion is filled by people that want to go to the grocery store every day rather than going once a week. Meanwhile, those that commute to work, are still going to do so because they have to. If the commute gets too bad, then some people will decide to move. On the other side of the spectrum, at some point there are so many people that want to go into the city every day - you can't do it with single occupancy vehicles and roads. It's a scaling problem. For example, someone did an analysis of parking decks in Seattle and whether there were not enough of them. They found if there were all filled and everyone then tried to leave - it would take 2 days for all the vehicles to exit the city. There are certainly many aspects to consider.
l2silver 2y ago
I agree with the urban planning bias here, especially the idea that you shouldn't build more roads to fight congestion because more people will use them, and thus they'll reach the same saturation point anyways. Mind boggling that this is an accepted principal, and one that is completely disregarded when it comes to any form of transport that isn't a car.
- kiba 2y ago
  Roads are incredibly low capacity for the value we get out of them.
HDThoreaun 2y ago
Absolutely agree. I really think the concept of induced demand with highways is misleading. Im not even sure reducing traffic is the point of highway expansion, pretty sure induced demand is literally the goal.
ilyagr 2y ago
I agree, "induced demand" is a word phrase to rally behind. The argument must be (and, I believe, is) that induced demand for buses and trains is far cheaper to a society than induced demand for cars. Adding a train car at a peak time serves a lot more people than adding a highway lane at a peak time. I'm actually curious to compare them. Apparently, 100 people is a reasonable capacity for a train car (200 is possible for BART at rush hour). A lane of 100 single-occupancy cars in a traffic jam is about a third of a mile. So, an extra car lane a mile long is about an extra half a train, give it take.
- AnthonyMouse 2y ago
  > So, an extra car lane a mile long is about an extra half a train, give it take. The problem with this math is the last mile. With a road network you have highways with multiple lanes and a lot of traffic, and those branch out into streets with fewer lanes but more destinations. You can run a train next to the highway and it will achieve much more throughput, but as soon as you get to the offramp, what now? Those 100 passengers all have different destinations that fork off in every direction. You can't run 100 train cars one for each passenger, that's even worse than the road cars. But you also can't just dump them all right there, miles away from where they want to be. The reason this works in NYC is the density. You can actually get 100 people who are all going to the same place at the same time. Which is also the only way to make it work anywhere else: Build higher density housing. It cannot work in the suburbs because there isn't enough density to run high-occupancy mass transit at a viable frequency. Whereas in that environment having the occasional four or eight lane highway increases carrying capacity along more than its own length. The single-lane surface streets that branch off in every direction have a vast amount of otherwise unused carrying capacity, which a highway lane unlocks by connecting low-density destinations together. And which you can't unlock with mass transit because those destinations don't have the density for mass transit, even if the path directly parallel to the highway does. The problem isn't cars or highways, it's zoning density restrictions.
  - ilyagr 2y ago
    These are all good points. High-density housing makes trains easier. Conversely, trains induce demand for high-density housing near the stations. There are many other considerations that need to be taken into consideration to make trains useful: frequency, right-of-way on road crossings (often a problem for light rail), right-of-way vs cargo trains (long-distance trains in the US), ... > The single-lane surface streets that branch off in every direction have a vast amount of otherwise unused carrying capacity, which a highway lane unlocks by connecting low-density destinations together. And which you can't unlock with mass transit because those destinations don't have the density for mass transit, even if the path directly parallel to the highway does. In a lot of suburbia, there are large parking lots near train stations. In theory, your point is a great advertisement for this setup. In practice, I never lived in a place where driving to the train station was convenient, but it's quite possible that is an accident. For one, parking lots have to be truly large to fit the number of people that would fit in a train car.
throwaway2037 2y ago
From my personal experience, growing up, people used the term induced demand in a strictly negative sense to describe road expansion plans. Then I lived in cities as an adult where new metro lines opened. The effect is real! Whole neighborhoods would get much more foot traffic after a new station opens. In this case, most people would describe the induced demand as positive.
bluecalm 2y ago
You can think of it in terms of simpler concept: "giving people free stuff causes more people to take free stuff". Cars and infrastructure for them is heavily subsidized so building more if it (giving free stuff away) induces more people to use it. As car infrastructure has a cost which car drivers don't cover building more if it is very expensive for everyone else that's why we shouldn't want more if it.

hammock 2y ago

> The induced demand argument in this case would be: "If we buy more copies of those books, the queue wont disappear, since it is so long, but also, if the queue gets shorter, we might have people who don't use the library because of the queue start using it. We would be no better off!". https://en.wikipedia.org/wiki/Jevons_paradox# https://en.wikipedia.org/wiki/Jevons_paradox#

tromp 2y ago

Except that having more car traffic induces more pollution, more casualties, and more time spent unproductively (you can do other things on public transit, or get exercise commuting by bike), whereas more book reading has few downsides.

rufus_foreman 2y ago
>> you can do other things on public transit, What can I do on public transit that people don't do in a car in traffic?
- Jensson 2y ago
  Browse your phone? Everyone does that in public transit, drivers don't do that in cars. You could read HN and post messages for example.
  - tekla 2y ago
    > drivers don't do that in cars See the problem is that they do, right before they drive into a pedestrian or stationary object.
- basil-rash 2y ago
  Get harassed by homeless? Or just men in general, if you’re a remotely attractive female (using the broadest term available as it certianly isn’t restricted to what we’d appropriately call “women”).
  - Jensson 2y ago
    Do you think public transit is full of drunkards? Its mostly tired people getting to or from work, those doesn't harass a lot of people. When its late and its a lot of drunks on public transit sure, but not on normal commutes. Columns I've read from women getting harassed its mostly about dance floors at clubs, not commute trains, when people aren't drunk they mostly keep their hands to themselves.

currymj 2y ago

i think the point of "induced demand" is that you sometimes can't really fix -- specifically -- traffic or parking congestion problems by building more. if you widen the roads, in many cases it won't make your commute any quicker. if you add more parking spots downtown, more people will drive downtown. it's not that there's no benefit to the wider road or parking spots, just that the benefit people really care about -- less traffic and quicker trips, less time searching for a parking spot -- often fails to materialize.

rufus_foreman 2y ago
>> if you add more parking spots downtown, more people will drive downtown But that's good if you wan't more people to drive downtown, isn't it? What am I missing here?
- Jensson 2y ago
  > What am I missing here? That downtown is now a concrete hellscape instead of a pleasant place to be. Your solution ensures that always happens, overall people prefer less infrastructure built for cars, but if it is there of course they will use it.
  - HDThoreaun 2y ago
    This just isnt true. Every metro area in the US has highways. Including the dense ones. NYC and Chicago are not concrete hellscapes
    - Jensson 2y ago
      You say NYC and Chicago has enough highways to fill demand so there is no congestion? I am fairly certain that isn't true, I've read so much about congestion problems in NYC at least. Adding enough roads to fill all demand leads to concrete hellscapes, that was the point, the guy I responded to thought it was reasonable to add roads until all demand was satisfied.

thefaux 2y ago

This is a flawed analogy and I think there is a false dichotomy by framing skepticism around building more highways as inherently anti-car. I'm going to go out on a limb and say most drivers do not enjoy traffic and most residents near busy roadways do not enjoy the effects of traffic on their neighborhood. The question is what is the best policy approach that manages all people's concerns. For me, the question is how can we get people to live and work in areas where it isn't necessary to inefficiently, and very expensively, move people to and from work. Since the 1950s, we have optimized for essentially the least efficient form of transit available. It seems completely bonkers to me that in the bay and other high density areas, you have many, many workers, particularly at the low end of the income scale, driving over an hour each way to work. It is an understandable and rational decision for the driver, but crazy to me for society.

cebert 2y ago
> For me, the question is how can we get people to live and work in areas where it isn't necessary to inefficiently, and very expensively, move people to and from work. I cannot comprehend why more firms aren’t embracing remote work more than they do. It helps alleviate a lot of these traffic challenges and can result in reduced carbon footprints as well as more happy employees. I hope we start considering remote work as a solution to some of these problems more in the future.
deleted 2y ago
[deleted]
throwaway2037 2y ago
Yeah, I agree. Most built up areas in California are horribly planned!

lkurtz 2y ago

I don’t think this analogy is quite correct. Driving on a particular route is not a driver’s objective like reading a particular book is a reader’s objective. The driver’s objective is arriving at a destination. The objective in driving is not a finite resource, but the multiple route options to the objective can be, which differs substantially from a library queue.

thereisnospork 2y ago
Let's consider a library with both a manned librarian and a self checkout, two different queues, same objective. Let's call the self checkout the 'highway' queue and the manned one the 'surface street' queue. Each of which could be expanded to improve throughput (more lanes:more self checkout lanes, more streets:more librarians). Ultimately the problem with anti-car rhetoric is that it seeks to limit access to the objective because it is "wrong" to use a self checkout lane and people must be forced to check books out in the morally correct manner. No one (reasonable) has a problem with the library adopting a mobile checkout app, which let's call mass transit. But crippling self checkout to force adoption of the mobile checkout app could be at best described as a 'dark pattern', forcing people to check out books 'the right way' at the cost of overall readership.
- troupo 2y ago
  The people who freely use terms like "anti-car" always assume that the car is always the fastest most efficient way of getting anywhere... and then sit stuck in standstill on a 6-10-lane highway
  - fragmede 2y ago
    don't forget driving around looking for parking for 20 mins as well
- lkurtz 2y ago
  In your example, replacing bulky self-checkout machines (analogous to removing road/surface parking real estate) offers a significant benefit to everyone. More room for what everyone actually wants most: books. The preference for self-checkout machines forces a cost on everyone for the benefit of a few.

tidbits 2y ago

Books are not a finite resource? Obviously there is a finite number of trees but there are enough for it not to be a bottleneck. Land on the hand is a finite resource, especially in large, urban cities. There is no way to design a highway or other car infrastructure that will meet the demands of any reasonably sized city without dedicating an unreasonable amount of land to cars. Anyway, Ray explains it better than I could and he agrees that the term is bad: https://youtu.be/za56H2BGamQ https://youtu.be/za56H2BGamQ

ksplicer 2y ago

What you are missing is that every time we widen roads to allow more car throughput we are making every other type of transit and mobility less attractive. Busy streets with big parking lots are unpleasant to walk or bike along, so people just drive to their destinations instead, which makes the street even busier, louder, and smellier starts this cycle all over again. Every time a road is widened or a new parking lot is added the city also becomes less dense, making getting anywhere useful more time consuming. Drivers have to spend longer on the road to get where they want to go, public transit gets more expensive as routes get longer, and walking and biking quickly become too time consuming. There is just a maximum density that cars can support which works totally fine for suburbs but breaks down in denser cities. Personally I think Park and Ride programs are the most reasonable compromise.

kjkjadksj 2y ago
People always seem to forget the bus takes advantage of having multiple travel lanes and faster intersection clearance too. City of LA is starting to take advantage of their wide roads and put in bus only lanes, something they could easily do with some paint since the pavement already exists.
- ksplicer 2y ago
  You don't need more than two lanes to dedicate one to buses.

seadan83 2y ago

Perhaps a library vs a commercial book store might have worked as a better analogy. The queue theory part of it I think breaks down a lot. Induced demand is not only about queue theory, but also choosing between options. In short though, induced demand is somewhat simple. If it takes 10 minutes to drive and 30 minutes to take a bus, then I drive. If it takes 30 minutes to drive and 10 minutes to take a bus, then I take the bus. Eventually enough people choose to drive, or take a bus, that that mode becomes congested/inconvenient enough that people start making other choices. In other words, there are some people who avoid highways during rush hour because the traffic jams are bad. If the highway is widened, then they would join the rush hour once again and be part of the traffic jams. Induced demand is about taking away the reason why people avoid something, and thereby doing so they change their behavior to start doing that thing.

HDThoreaun 2y ago
Yea but really the choice here is "go somewhere vs stay home", not "car vs bus". Highway expansion leads to more people travelling because bus service is non existent in the vast majority of the country. Of course some people need to go where theyre going, but on the margins more people will go to the city or what not if traffic is lower.
- seadan83 2y ago
  Good points. Yeah, as the cost of travel goes up, people make various decisions: bite-the-bullet, find alternatives, delay, consolidate, and/or go without. As the cost decreases, the incentives to find alternatives, delay or consolidate trips goes down (which means roads are then used for less important reasons and less efficiently - why go to the grocery store once a week if you can go every day in half the travel time?) I would agree, at some point when all alternatives are equally unattractive (or non-existent), then going without is a more attractive option. Though, the "consolidate" option is a big one to consider. Rather than going to the city every day, perhaps people could do so every other day for the same benefit. If traffic is bad, then people will go less often (frequency of travel is a function of cost). Thus, in some cases, highway expansion is filled by people that want to go to the grocery store every day rather than going once a week. Meanwhile, those that commute to work, are still going to do so because they have to. If the commute gets too bad, then some people will decide to move. On the other side of the spectrum, at some point there are so many people that want to go into the city every day - you can't do it with single occupancy vehicles and roads. It's a scaling problem. For example, someone did an analysis of parking decks in Seattle and whether there were not enough of them. They found if there were all filled and everyone then tried to leave - it would take 2 days for all the vehicles to exit the city. There are certainly many aspects to consider.

l2silver 2y ago

I agree with the urban planning bias here, especially the idea that you shouldn't build more roads to fight congestion because more people will use them, and thus they'll reach the same saturation point anyways. Mind boggling that this is an accepted principal, and one that is completely disregarded when it comes to any form of transport that isn't a car.

kiba 2y ago
Roads are incredibly low capacity for the value we get out of them.

HDThoreaun 2y ago

Absolutely agree. I really think the concept of induced demand with highways is misleading. Im not even sure reducing traffic is the point of highway expansion, pretty sure induced demand is literally the goal.

ilyagr 2y ago

I agree, "induced demand" is a word phrase to rally behind. The argument must be (and, I believe, is) that induced demand for buses and trains is far cheaper to a society than induced demand for cars. Adding a train car at a peak time serves a lot more people than adding a highway lane at a peak time. I'm actually curious to compare them. Apparently, 100 people is a reasonable capacity for a train car (200 is possible for BART at rush hour). A lane of 100 single-occupancy cars in a traffic jam is about a third of a mile. So, an extra car lane a mile long is about an extra half a train, give it take.

AnthonyMouse 2y ago
> So, an extra car lane a mile long is about an extra half a train, give it take. The problem with this math is the last mile. With a road network you have highways with multiple lanes and a lot of traffic, and those branch out into streets with fewer lanes but more destinations. You can run a train next to the highway and it will achieve much more throughput, but as soon as you get to the offramp, what now? Those 100 passengers all have different destinations that fork off in every direction. You can't run 100 train cars one for each passenger, that's even worse than the road cars. But you also can't just dump them all right there, miles away from where they want to be. The reason this works in NYC is the density. You can actually get 100 people who are all going to the same place at the same time. Which is also the only way to make it work anywhere else: Build higher density housing. It cannot work in the suburbs because there isn't enough density to run high-occupancy mass transit at a viable frequency. Whereas in that environment having the occasional four or eight lane highway increases carrying capacity along more than its own length. The single-lane surface streets that branch off in every direction have a vast amount of otherwise unused carrying capacity, which a highway lane unlocks by connecting low-density destinations together. And which you can't unlock with mass transit because those destinations don't have the density for mass transit, even if the path directly parallel to the highway does. The problem isn't cars or highways, it's zoning density restrictions.
- ilyagr 2y ago
  These are all good points. High-density housing makes trains easier. Conversely, trains induce demand for high-density housing near the stations. There are many other considerations that need to be taken into consideration to make trains useful: frequency, right-of-way on road crossings (often a problem for light rail), right-of-way vs cargo trains (long-distance trains in the US), ... > The single-lane surface streets that branch off in every direction have a vast amount of otherwise unused carrying capacity, which a highway lane unlocks by connecting low-density destinations together. And which you can't unlock with mass transit because those destinations don't have the density for mass transit, even if the path directly parallel to the highway does. In a lot of suburbia, there are large parking lots near train stations. In theory, your point is a great advertisement for this setup. In practice, I never lived in a place where driving to the train station was convenient, but it's quite possible that is an accident. For one, parking lots have to be truly large to fit the number of people that would fit in a train car.

throwaway2037 2y ago

From my personal experience, growing up, people used the term induced demand in a strictly negative sense to describe road expansion plans. Then I lived in cities as an adult where new metro lines opened. The effect is real! Whole neighborhoods would get much more foot traffic after a new station opens. In this case, most people would describe the induced demand as positive.

bluecalm 2y ago

You can think of it in terms of simpler concept: "giving people free stuff causes more people to take free stuff". Cars and infrastructure for them is heavily subsidized so building more if it (giving free stuff away) induces more people to use it. As car infrastructure has a cost which car drivers don't cover building more if it is very expensive for everyone else that's why we shouldn't want more if it.