5 ms·

If you go over 3 lanes per direction you have absolutely failed at designing a road.

jcranmer 7y ago
Or you have the traffic density required to move that many cars. The George Washington Bridge, which essentially carries all traffic that travels through New York City that isn't going to/from Manhattan and some parts of Long Island, carries 9 lanes in each direction on two levels, and absolutely needs that many lanes.
- tty2300 7y ago
  If you ever fill 3 lanes than you need to seriously invest in public transport. More than 3 lanes is never a sane idea. 9 lanes is an absolute atrocity.
  - 0x54D5 7y ago
    Or you live in a megalopolis. I-95 between NYC and Philadelphia is 4 or 5 lanes wide at times and that's in the middle of nowhere New Jersey. Even if you build public transportation people won't use it. You'll just be shifting the problem. Now instead of wider highways you need more trains and bigger parking lots at the train stations. Going further south I-95 between Philadelphia and Wilmington is 4 lanes wide near major interchanges. Approaching Baltimore it reaches 6 lanes wide at times. In DC the Beltway is itself 4-6 lanes wide and always packed. Your off the cuff "just do this" comments are not helpful.
  - pdonis 7y ago
    > If you ever fill 3 lanes than you need to seriously invest in public transport. Um, you do realize that the George Washington Bridge is in New York City, one of the largest cities in the world, with an extensive system of public transportation? The idea that if NYC would just invest in some public transport those 9 lanes would go down to 3 is laughable.
    - Tepix 7y ago
      I somewhat agree with the parent poster. The city's design should not require 9 lanes. I didn't see 9 lanes roads in Tokyo and it's bigger than NYC.
      - pdonis 7y ago
        > I didn't see 9 lanes roads in Tokyo and it's bigger than NYC. That's because Tokyo and NYC are different cities in different countries, populated by people with very different preferences. My point was not that NYC's public transportation and highway systems are optimal by the criterion of "optimal" that the poster I responded to appears to be using. My point was that the fact that NYC doesn't look optimal to him is not that NYC has simply failed to consider public transportation as an alternative. It's that, as I said, NYC is populated by people with different preferences from his, and NYC's public transportation and highway systems reflect those preferences.
        baroffoos 7y ago
        That's because NYC and most of America is dysfunctional to the point where people think that a 18 lane road is not just necessary but actually a good idea. Not a single place in the US has good public transport. Maybe good to US standards but thats a low bar.
        pdonis 7y ago
        > That's because NYC and most of America is dysfunctional Not to those of us who live in America. That's the nice thing about having different countries, and different states, cities, etc. within countries: it enables people with widely different definitions of "functional" to all find a place to live, instead of everybody having to conform to somebody's fixed idea of how people should live.
        baroffoos 7y ago
        Well I guess if you enjoy spending hours stuck in traffic and having air that slowly kills you.
maxxxxx 7y ago
Come to LA and you will see 5 or 6 easily. And LA has the added bonus of having left and right exits which they tell you about only a few hundred meters before. You see plenty of cars going from all the way right to all the way left in a hurry...
- ajmurmann 7y ago
  Great example of the failed road design the parent is referencing. Not to mention the failed protocols (traffic rules) the US has that further diminish throughput.
m463 7y ago
US roads have low speed limits, which limits shortening of the vehicle at relativistic speeds. (= capacity)

Or you have the traffic density required to move that many cars. The George Washington Bridge, which essentially carries all traffic that travels through New York City that isn't going to/from Manhattan and some parts of Long Island, carries 9 lanes in each direction on two levels, and absolutely needs that many lanes.

tty2300 7y ago
If you ever fill 3 lanes than you need to seriously invest in public transport. More than 3 lanes is never a sane idea. 9 lanes is an absolute atrocity.
- 0x54D5 7y ago
  Or you live in a megalopolis. I-95 between NYC and Philadelphia is 4 or 5 lanes wide at times and that's in the middle of nowhere New Jersey. Even if you build public transportation people won't use it. You'll just be shifting the problem. Now instead of wider highways you need more trains and bigger parking lots at the train stations. Going further south I-95 between Philadelphia and Wilmington is 4 lanes wide near major interchanges. Approaching Baltimore it reaches 6 lanes wide at times. In DC the Beltway is itself 4-6 lanes wide and always packed. Your off the cuff "just do this" comments are not helpful.
- pdonis 7y ago
  > If you ever fill 3 lanes than you need to seriously invest in public transport. Um, you do realize that the George Washington Bridge is in New York City, one of the largest cities in the world, with an extensive system of public transportation? The idea that if NYC would just invest in some public transport those 9 lanes would go down to 3 is laughable.
  - Tepix 7y ago
    I somewhat agree with the parent poster. The city's design should not require 9 lanes. I didn't see 9 lanes roads in Tokyo and it's bigger than NYC.
    - pdonis 7y ago
      > I didn't see 9 lanes roads in Tokyo and it's bigger than NYC. That's because Tokyo and NYC are different cities in different countries, populated by people with very different preferences. My point was not that NYC's public transportation and highway systems are optimal by the criterion of "optimal" that the poster I responded to appears to be using. My point was that the fact that NYC doesn't look optimal to him is not that NYC has simply failed to consider public transportation as an alternative. It's that, as I said, NYC is populated by people with different preferences from his, and NYC's public transportation and highway systems reflect those preferences.
      - baroffoos 7y ago
        That's because NYC and most of America is dysfunctional to the point where people think that a 18 lane road is not just necessary but actually a good idea. Not a single place in the US has good public transport. Maybe good to US standards but thats a low bar.
        pdonis 7y ago
        > That's because NYC and most of America is dysfunctional Not to those of us who live in America. That's the nice thing about having different countries, and different states, cities, etc. within countries: it enables people with widely different definitions of "functional" to all find a place to live, instead of everybody having to conform to somebody's fixed idea of how people should live.
        baroffoos 7y ago
        Well I guess if you enjoy spending hours stuck in traffic and having air that slowly kills you.

maxxxxx 7y ago

Come to LA and you will see 5 or 6 easily. And LA has the added bonus of having left and right exits which they tell you about only a few hundred meters before. You see plenty of cars going from all the way right to all the way left in a hurry...

ajmurmann 7y ago
Great example of the failed road design the parent is referencing. Not to mention the failed protocols (traffic rules) the US has that further diminish throughput.

m463 7y ago

US roads have low speed limits, which limits shortening of the vehicle at relativistic speeds. (= capacity)