6 ms·

Freeways are mass transportation, it might not be the kind you like, but they are pretty effective at getting large numbers of people from origin to destination

by dsl 7y ago

Freeways are mass transportation, it might not be the kind you like, but they are pretty effective at getting large numbers of people from origin to destination. The peak capacity of a mile of track will always be less than that of a mile of highway. But we don't have anywhere to put either because we refuse to build up and ruin a bunch of NIMBYs views.

jacques_chester 7y ago
> The peak capacity of a mile of track will always be less than that of a mile of highway. I'd be interested to hear why you think this.
melling 7y ago
Where are you getting your numbers? Are you making them up? How many passenger cars can you get down a mile of highway per hour? I love freeways. It’s just that during rush hour (and holiday weekends), they’re extremely congested. We’ve got local lanes, express lanes, and Waze to help figure out which one to take. Roads don’t scale very well. Mass transit would more acceptable if we can increase the speed. China has low-medium speed maglevs, for example, that will travel 100-120 miles per hour. https://www.cnn.com/travel/article/china-driverless-maglev-trains/index.html https://www.cnn.com/travel/article/china-driverless-maglev-t...
- rayiner 7y ago
  To use some example numbers. VA7, which goes from the Dulles area where many DC-area data centers are located, through Reston where many tech companies' offices are located, to near DC, carries 50,000-100,000 vehicles per day, and is congested pretty much all day. The Metro Silver line, which follows roughly the same route, theoretically destroys that. An 8-car Metro train carries 1,400 people. With 8-minute headways, that's 7.5 trains per hour, 90 trains over a 12-hour commuting day, or 126,000 people. Except the actual ridership of the Silver Line is just about 17,000 people per day, and declining. Why? Because it's useless for most people. It takes you to DC at one end, and the airport at the other, and a few places that happen to be on the way. But most people who live in that area don't commute to DC. People take VA7 to go from say Sterling (where there is no metro station) to Tyson's Corner. They have to get in a car to use Metro anyway, and by the time they do that, it's faster to just drive to Tysons instead of getting on the Metro for the segment of the trip Metro covers. On the other side of DC, the Maryland suburbs are served by no fewer than 37.5 trains per hour (15 on the Green/Yellow, 15 on the Blue/Silver, and 7.5 on the Orange). That's 50,000 people per hour! But the cars are pretty much empty in Maryland, because few people commute into DC. In the height of irony, Metro is moving one of its main employment centers to Lanham Maryland, located on the terminus of the orange line. That means it's not actually commutable by Metro for most part. Folks who work for WMATA aren't living in DC and doing a reverse commute. They're living in Bowie or Largo or College Park or Hyattsville (the surrounding towns). Taking Metro would involve going all the way to DC, switching from the Green/Yellow or Blue/Silver to the Orange, then going back all the way.
  - melling 7y ago
    Hang on... you’re giving me confirmation bias. You’re cherry picking one example that confirms your bias. No first principles reasoning. You’re giving some specific example about a setup in Washington DC. This has absolutely nothing to do with how well mass transit can do versus cars. It’s one specific implementation. In NYC, for example, 5.5 million people take the subway per day. How much highway will you need to carry that many people?
    - rayiner 7y ago
      “How much highway would you need to move 5.5 million people into and through a dense downtown core” is a question almost no city in the US besides New York needs to ask. NYC is uniquely dense: https://www.austincontrarian.com/austincontrarian/2012/09/the-50-densest-american-metropolitan-areas-by-weighted-density.html https://www.austincontrarian.com/austincontrarian/2012/09/th.... The weighted population density (the density in the parts of the metro area where people live) is 30,000 people per square mile. LA and SF, the next most dense, are less than half as dense, at 12,000. DC, at 6,400, is about 1/5 the density of New York. Portland and Seattle are even less dense, at 4,000-5,000, which is about the national average. The Silver Line example is much more illustrative of a typical place in the US. In these places, the higher theoretical capacity of rail is irrelevant, because the commuting pattern isn’t about bringing a large number of people along a few major paths to a downtown job center. It’s about shuttling people between job clusters spread out among the suburbs: http://www.robertmanduca.com/projects/jobs.html http://www.robertmanduca.com/projects/jobs.html (scroll over to Northern VA, west of DC). There might be heavily used corridors like VA7, but the commutes both start and end in suburban locations. You couldn’t pick out a few key paths where being able to move 100,000 people a day from point A to point B and intermediate points would really be all that helpful.
      - melling 7y ago
        Someone made this claim: “The peak capacity of a mile of track will always be less than that of a mile of highway. ” All we’re doing is arguing by examples. Clearly, depending on the population it’s simply not true. I don’t know the specifics in each case. I’ve been stuck in huge traffic jams in Seattle, New York/New Jersey, Washington DC, Virginia, Philadelphia, etc. I’d say we need more mass transit in those places. Yes, mass transit needs to go where a certain number of people want to go. However, we’ve ignored mass transit in the US and we complain that it doesn’t work, when it seems to work everywhere else in the world. So, we’ve mostly build minimal mass transit and lots of roads in the US and are using that as an example that mass transit doesn’t work.
deleted 7y ago
[deleted]
dheera 7y ago
Not sure I agree with this. Freeways carry about 2K cars per hour per lane [0], which in the USA translates to about 2-3K people per hour per lane. Rail transit systems can serve much, much more than thas -- typically 20K to 30K per hour per track in Europe and upto 54K in NYC and 81K in Hong Kong [1]. These are actual competent train systems that run trains every couple of minutes, not the idiotic once-per-hour Caltrain. [0] http://onlinepubs.trb.org/onlinepubs/circulars/EC018/08_52.pdf http://onlinepubs.trb.org/onlinepubs/circulars/EC018/08_52.p... [1] https://books.google.com/books?id=NbYqQSQcE2MC&pg=PA136&lpg=PA136&dq=hong+kong+passengers+per+hour+per+track&source=bl&ots=mcjCYmyqX3&sig=ACfU3U3RcUGl_U1__8wsSybAxhWD1X-y_w&hl=zh-TW&sa=X&ved=2ahUKEwjt_c-C5t3iAhU-HDQIHW-PCXwQ6AEwCXoECAkQAQ#v=onepage&q=hong%20kong%20passengers%20per%20hour%20per%20track&f=false https://books.google.com/books?id=NbYqQSQcE2MC&pg=PA136&lpg=...
francisofascii 7y ago
Don't forget about buses, which use highways but are much more efficient. Buses with dedicated bus lanes and high frequency service (every few minutes) is the way to go.

by dsl 7y ago

jacques_chester 7y ago

> The peak capacity of a mile of track will always be less than that of a mile of highway. I'd be interested to hear why you think this.

melling 7y ago

Where are you getting your numbers? Are you making them up? How many passenger cars can you get down a mile of highway per hour? I love freeways. It’s just that during rush hour (and holiday weekends), they’re extremely congested. We’ve got local lanes, express lanes, and Waze to help figure out which one to take. Roads don’t scale very well. Mass transit would more acceptable if we can increase the speed. China has low-medium speed maglevs, for example, that will travel 100-120 miles per hour. https://www.cnn.com/travel/article/china-driverless-maglev-trains/index.html https://www.cnn.com/travel/article/china-driverless-maglev-t...

rayiner 7y ago
To use some example numbers. VA7, which goes from the Dulles area where many DC-area data centers are located, through Reston where many tech companies' offices are located, to near DC, carries 50,000-100,000 vehicles per day, and is congested pretty much all day. The Metro Silver line, which follows roughly the same route, theoretically destroys that. An 8-car Metro train carries 1,400 people. With 8-minute headways, that's 7.5 trains per hour, 90 trains over a 12-hour commuting day, or 126,000 people. Except the actual ridership of the Silver Line is just about 17,000 people per day, and declining. Why? Because it's useless for most people. It takes you to DC at one end, and the airport at the other, and a few places that happen to be on the way. But most people who live in that area don't commute to DC. People take VA7 to go from say Sterling (where there is no metro station) to Tyson's Corner. They have to get in a car to use Metro anyway, and by the time they do that, it's faster to just drive to Tysons instead of getting on the Metro for the segment of the trip Metro covers. On the other side of DC, the Maryland suburbs are served by no fewer than 37.5 trains per hour (15 on the Green/Yellow, 15 on the Blue/Silver, and 7.5 on the Orange). That's 50,000 people per hour! But the cars are pretty much empty in Maryland, because few people commute into DC. In the height of irony, Metro is moving one of its main employment centers to Lanham Maryland, located on the terminus of the orange line. That means it's not actually commutable by Metro for most part. Folks who work for WMATA aren't living in DC and doing a reverse commute. They're living in Bowie or Largo or College Park or Hyattsville (the surrounding towns). Taking Metro would involve going all the way to DC, switching from the Green/Yellow or Blue/Silver to the Orange, then going back all the way.
- melling 7y ago
  Hang on... you’re giving me confirmation bias. You’re cherry picking one example that confirms your bias. No first principles reasoning. You’re giving some specific example about a setup in Washington DC. This has absolutely nothing to do with how well mass transit can do versus cars. It’s one specific implementation. In NYC, for example, 5.5 million people take the subway per day. How much highway will you need to carry that many people?
  - rayiner 7y ago
    “How much highway would you need to move 5.5 million people into and through a dense downtown core” is a question almost no city in the US besides New York needs to ask. NYC is uniquely dense: https://www.austincontrarian.com/austincontrarian/2012/09/the-50-densest-american-metropolitan-areas-by-weighted-density.html https://www.austincontrarian.com/austincontrarian/2012/09/th.... The weighted population density (the density in the parts of the metro area where people live) is 30,000 people per square mile. LA and SF, the next most dense, are less than half as dense, at 12,000. DC, at 6,400, is about 1/5 the density of New York. Portland and Seattle are even less dense, at 4,000-5,000, which is about the national average. The Silver Line example is much more illustrative of a typical place in the US. In these places, the higher theoretical capacity of rail is irrelevant, because the commuting pattern isn’t about bringing a large number of people along a few major paths to a downtown job center. It’s about shuttling people between job clusters spread out among the suburbs: http://www.robertmanduca.com/projects/jobs.html http://www.robertmanduca.com/projects/jobs.html (scroll over to Northern VA, west of DC). There might be heavily used corridors like VA7, but the commutes both start and end in suburban locations. You couldn’t pick out a few key paths where being able to move 100,000 people a day from point A to point B and intermediate points would really be all that helpful.
    - melling 7y ago
      Someone made this claim: “The peak capacity of a mile of track will always be less than that of a mile of highway. ” All we’re doing is arguing by examples. Clearly, depending on the population it’s simply not true. I don’t know the specifics in each case. I’ve been stuck in huge traffic jams in Seattle, New York/New Jersey, Washington DC, Virginia, Philadelphia, etc. I’d say we need more mass transit in those places. Yes, mass transit needs to go where a certain number of people want to go. However, we’ve ignored mass transit in the US and we complain that it doesn’t work, when it seems to work everywhere else in the world. So, we’ve mostly build minimal mass transit and lots of roads in the US and are using that as an example that mass transit doesn’t work.

deleted 7y ago

[deleted]

dheera 7y ago

Not sure I agree with this. Freeways carry about 2K cars per hour per lane [0], which in the USA translates to about 2-3K people per hour per lane. Rail transit systems can serve much, much more than thas -- typically 20K to 30K per hour per track in Europe and upto 54K in NYC and 81K in Hong Kong [1]. These are actual competent train systems that run trains every couple of minutes, not the idiotic once-per-hour Caltrain. [0] http://onlinepubs.trb.org/onlinepubs/circulars/EC018/08_52.pdf http://onlinepubs.trb.org/onlinepubs/circulars/EC018/08_52.p... [1] https://books.google.com/books?id=NbYqQSQcE2MC&pg=PA136&lpg=PA136&dq=hong+kong+passengers+per+hour+per+track&source=bl&ots=mcjCYmyqX3&sig=ACfU3U3RcUGl_U1__8wsSybAxhWD1X-y_w&hl=zh-TW&sa=X&ved=2ahUKEwjt_c-C5t3iAhU-HDQIHW-PCXwQ6AEwCXoECAkQAQ#v=onepage&q=hong%20kong%20passengers%20per%20hour%20per%20track&f=false https://books.google.com/books?id=NbYqQSQcE2MC&pg=PA136&lpg=...

francisofascii 7y ago

Don't forget about buses, which use highways but are much more efficient. Buses with dedicated bus lanes and high frequency service (every few minutes) is the way to go.