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Comment by Retric

9 years ago

A well managed train system can manage 1 car per line per 5 minutes. 2000 * 60 / 5 = 24,000 people per hour. Highways can handle 2,000 - 2200 vehicles per lane or so at the low end 1/12 but that's very much an edge case. Most lines are closer to one train every 20 minutes and you can average 3 people per car which makes them equivalent.

The real issue is not highways, but what happens when people try and get off or onto them. It's possible but rare to do this well.

Do you mean a shitty managed train system, right? In London at peak time there is one train every two minutes, in Moscow one per minute. One train every 5 minutes is the off peak frequency in London when you are actually complaining that you are waiting too long.

  • At the peak times for the most used stations there is a car that frequently sure, but if use look at the overall system they don't send anywhere close to 60 * 24 = 1440 trains past every station in each direction per day. Further trains going to different stations often share the same track because you need more throughput in the city center than at the furthest stations. But, just because the edge stations get less use does not mean the track is cheaper to construct.

    • The max throughout is the number that we should care about - they provide fewer cars per minute not because they're physically incapable of doing it, just because there isn't demand. And it would be the same in a car-centric situation as well - lower throughput in off hours.

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It's less of an edge case than you may think, given solo ridership numbers here in the USA. 75% commute alone.

https://www.census.gov/hhes/commuting/files/2014/acs-32.pdf

  • The average over the full US is kind of meaningless as most areas don't have traffic problems. It's only large city's that actually matter in this assessment.

    On page 4, 2006: 80% used a carpool or single occupancy car. 2013: 76% used a carpool or single occupancy car which is counter to their narrative. Further, metro areas are rather large, I commute less than 3 miles on secondary roads in the DC metro area from just outside the beltway to just inside of it and encounter approximately zero traffic.