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Comment by theluketaylor | Hacker News Reader

Montreal's new REM is running pretty short trains at 30 trains per hour and still has capacity for over 40,000 people per hour. 60 trains per hour with longer trains can do even more. Only a handful of places on earth have the density to require any more capacity than a fully automated double track metro can deliver, and those places all have the tax base to easily support quad tracking or actually better is building multiple parallel lines nearby with strong connectivity.

Nearly all metros with capacity issues have old, slow sections that limit the entire network (NYC looking at you) or have paused on expanding the network for generations (NYC looking at you again, 2nd ave subway notwithstanding).

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> Nearly all metros with capacity issues have old, slow sections that limit the entire network (NYC looking at you) or have paused on expanding the network for generations (NYC looking at you again, 2nd ave subway notwithstanding).

You're posting this on an article about a line that runs at 158% occupancy during peak times, in a city that certainly hasn't shirked on modernisation or expansion. If you expand far enough then even metros hit their limits.

(Admittedly that city, or rather metropolitan area, is also the most populous in the world).

Not to mention Yamanote line also shares the same route with many other train lines that serve as extra capacity and express service along segments of the route (Shonan Shinjuku Line, Saikyo Line, Keihin Tohoku Line, etc), as well as multiple other alternate lines that more or less duplicate segments of Yamanote Line (Shibuya-Ikebukuro is also served by Fukutoshin Line with local and express service on a parallel route, for instance). And yet basically all of these lines exceed max capacity daily.

So mass transit isn't exempt from induced demand, but for the width of track it produces much more capacity than equivalent roads. I wonder if Tokyo decided to build a few more lines/expand the capacity of the existing ones (e.g. by building extra tunnels or elevated lines on existing rights of way), if there is a point where the train capacity really could exceed the peak demand the city could produce; but more interestingly, I wonder how many trips don't happen in car-dependent cities (or ones with decrepit transit like NYC) because of how inefficient their infrastructure is at moving people.

A noticeable effect to me of all this transit is that the car traffic on the roads usually is pretty minimal.

>A noticeable effect to me of all this transit is that the car traffic on the roads usually is pretty minimal.

I don't think that's a direct effect. Within most of Tokyo, using a car just isn't a viable option for many trips for most people. Lots of people don't own a car to begin with (a parking space at your home is usually very expensive, in addition to the costs of the car itself). And if you try to use it to go somewhere, where are you going to park it? Some big stores and malls of course have parking garages, but most other places don't, or there's paid parking that's expensive. And if you're going to work on a typical day, there's probably no place to park there: companies don't provide parking for employees, they give you a pass for the transit system to get to work.

I think, overall, the reason car traffic is pretty minimal in Tokyo is because using a car just isn't very convenient most of the time, so people don't.

> I wonder if Tokyo decided to build a few more lines/expand the capacity of the existing ones (e.g. by building extra tunnels or elevated lines on existing rights of way), if there is a point where the train capacity really could exceed the peak demand the city could produce

I doubt it - more capacity just means more population growth and more demand. Central London has reached a point where they're worried about the pedestrian capacity on some central bridges. But in what's already the most populous and second most economically productive metro area in the world, of course there are very real benefits to growing further.

> more interestingly, I wonder how many trips don't happen in car-dependent cities (or ones with decrepit transit like NYC) because of how inefficient their infrastructure is at moving people.

NYC does pretty well, but yeah of course available transport affects what people can do. I saw an interesting conception of this as the "effective size" of a city, e.g. how many people and jobs there are within a 30- or 60-minute commute radius.

> A noticeable effect to me of all this transit is that the car traffic on the roads usually is pretty minimal.

Not my experience. Tokyo gets as gridlocked as anywhere else during rush hour, and they're constantly building new roads as well (including e.g. a fourth expressway ringroad).

Under JR's definitions 150% capacity means people have enough space to read a newspaper. It's 200%+ that is the image of Japanese people being pushed onto the train by the white gloved staff.

> Under JR's definitions 150% capacity means people have enough space to read a newspaper.

Having ridden on the Yamanote in peak time, I don't believe that.

How many years ago? Yamanote was above 200% average peak capacity as recently as the mid '00s

This year.

neither agreeing nor disagreeing - there's actually a design passenger count for train cars like any vehicles, rarely mentioned, and percent capacity is relative to that number.

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