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Sorry, the figure of 1600 cars per hour is complete and utter bullshit. If just 5 cars get through a signal on a 30 second cycle, that’s 600 cars per hour. For

Sorry, the figure of 1600 cars per hour is complete and utter bullshit. If just 5 cars get through a signal on a 30 second cycle, that’s 600 cars per hour. For a single intersection. How many intersections are there in a city? A well designed intersection can easily get 20 cars through per cycle. Don’t get me wrong, I’m a fan of bus lanes and really a fan of light rail. But I really hate this type of hype where basic assumptions don’t pass the smell test. And if you want to get into some real economics, a system like the LA Metro Authority operates at about 20% Fare Box Recovery. That means for every $1 of fare collected, a subsidy of $4 is required to keep the system running. At least when someone drives their own car, they are actually paying their own way.

jackvalentine 9y ago
> At least when someone drives their own car, they are actually paying their own way. Do they? The sheer amount of infrastructure for cars and parking make me question that statement.
- CodeWriter23 9y ago
  Taxes
  - jackvalentine 9y ago
    That doesn’t really answer the question.
    - CodeWriter23 9y ago
      How does it not? People pay their taxes, income, sales and use tax, gasoline, whatever form their local government uses to fund roads, and their fair share of the road use comes out of their pocket. So, yes, driving your own car IS actually paying your own way.
      - jackvalentine 9y ago
        Do people not pay their taxes for public transport too? You had quite specific numbers for the amount of the journey cost that the user pays for public transport, what are the equivalent numbers for drivers? My intuition is road and parking projects are so spectacularly expensive I doubt drivers are paying their full costs via petrol excise and registration fees. Obviously it's different in every city, but if we're going to have a conversation about the merits of subsidizing (or not) public transport then we should probably have figures for comparison on privately driven cars. "taxes" doesn't cut it. I can't vouch for the quality of this post, but it illustrates my thinking: https://www.citylab.com/transportation/2015/05/debunking-the-myth-that-only-drivers-pay-for-roads/393134/ https://www.citylab.com/transportation/2015/05/debunking-the... Perhaps you have better figures.
TheCoelacanth 9y ago
The numbers appear to be for how much traffic can pass in a single lane's worth of space. Their numbers make sense for a single traffic lane[1], one subway line[2] and one 2.5 meter (a bit narrower than a standard traffic lane) bike path[3], all of which take up pretty close to the same amount of space. [1] http://www.mikeontraffic.com/numbers-every-traffic-engineer-should-know/ http://www.mikeontraffic.com/numbers-every-traffic-engineer-... [2] https://www.thoughtco.com/passenger-capacity-of-transit-2798765 https://www.thoughtco.com/passenger-capacity-of-transit-2798... [3] https://nacto.org/wp-content/uploads/2016/04/5_Zhou-Xu-Wang-and-Sheng-Estimating-Capacity-of-Bicycle-Path-on-Urban-Roads-in-Hangzhou-China_2014.pdf https://nacto.org/wp-content/uploads/2016/04/5_Zhou-Xu-Wang-...
- CodeWriter23 9y ago
  A single lane does not tell the traffic story for an entire city.
  - TheCoelacanth 9y ago
    It would be nonsensical to state numbers for the total number of people can who move through an entire city because it is heavily dependent on how much space is dedicated to each mode of travel. They are making a comparison of how many people who can move through a given amount of space depending on what mode of transportation they are using.
    - CodeWriter23 9y ago
      The figure of 25,000 people/hour in buses makes sense to me in a city like L.A. This is where I'm taking issue with the whole article, their basis for analysis is apples-to-oranges.
      - TheCoelacanth 9y ago
        If you look at the sources I linked they give the estimates of 1900 vehicles per hour as the theoretical maximum capacity for a lane of traffic, 30k people per hour as the maximum capacity for a single subway line and 10k people per hour as the maximum capacity for a 2.5 meter bike path. Those are all pretty close to the numbers they gave for each mode of transit, so it seems reasonable to assume that they are basing their numbers on something similar to that. That is an apples-to-apples comparison because each of those things takes up very close to the same amount of space.

jackvalentine 9y ago

> At least when someone drives their own car, they are actually paying their own way. Do they? The sheer amount of infrastructure for cars and parking make me question that statement.

CodeWriter23 9y ago
Taxes
- jackvalentine 9y ago
  That doesn’t really answer the question.
  - CodeWriter23 9y ago
    How does it not? People pay their taxes, income, sales and use tax, gasoline, whatever form their local government uses to fund roads, and their fair share of the road use comes out of their pocket. So, yes, driving your own car IS actually paying your own way.
    - jackvalentine 9y ago
      Do people not pay their taxes for public transport too? You had quite specific numbers for the amount of the journey cost that the user pays for public transport, what are the equivalent numbers for drivers? My intuition is road and parking projects are so spectacularly expensive I doubt drivers are paying their full costs via petrol excise and registration fees. Obviously it's different in every city, but if we're going to have a conversation about the merits of subsidizing (or not) public transport then we should probably have figures for comparison on privately driven cars. "taxes" doesn't cut it. I can't vouch for the quality of this post, but it illustrates my thinking: https://www.citylab.com/transportation/2015/05/debunking-the-myth-that-only-drivers-pay-for-roads/393134/ https://www.citylab.com/transportation/2015/05/debunking-the... Perhaps you have better figures.

TheCoelacanth 9y ago

The numbers appear to be for how much traffic can pass in a single lane's worth of space. Their numbers make sense for a single traffic lane[1], one subway line[2] and one 2.5 meter (a bit narrower than a standard traffic lane) bike path[3], all of which take up pretty close to the same amount of space. [1] http://www.mikeontraffic.com/numbers-every-traffic-engineer-should-know/ http://www.mikeontraffic.com/numbers-every-traffic-engineer-... [2] https://www.thoughtco.com/passenger-capacity-of-transit-2798765 https://www.thoughtco.com/passenger-capacity-of-transit-2798... [3] https://nacto.org/wp-content/uploads/2016/04/5_Zhou-Xu-Wang-and-Sheng-Estimating-Capacity-of-Bicycle-Path-on-Urban-Roads-in-Hangzhou-China_2014.pdf https://nacto.org/wp-content/uploads/2016/04/5_Zhou-Xu-Wang-...

CodeWriter23 9y ago
A single lane does not tell the traffic story for an entire city.
- TheCoelacanth 9y ago
  It would be nonsensical to state numbers for the total number of people can who move through an entire city because it is heavily dependent on how much space is dedicated to each mode of travel. They are making a comparison of how many people who can move through a given amount of space depending on what mode of transportation they are using.
  - CodeWriter23 9y ago
    The figure of 25,000 people/hour in buses makes sense to me in a city like L.A. This is where I'm taking issue with the whole article, their basis for analysis is apples-to-oranges.
    - TheCoelacanth 9y ago
      If you look at the sources I linked they give the estimates of 1900 vehicles per hour as the theoretical maximum capacity for a lane of traffic, 30k people per hour as the maximum capacity for a single subway line and 10k people per hour as the maximum capacity for a 2.5 meter bike path. Those are all pretty close to the numbers they gave for each mode of transit, so it seems reasonable to assume that they are basing their numbers on something similar to that. That is an apples-to-apples comparison because each of those things takes up very close to the same amount of space.