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Comment by sofixa | Hacker News Reader

> I always thought trains (light rail, high speed, what ever) were so much better than cars. Have more traffic? Just add more trains, no extra rails needed. Yamanote line rush hour showed me how effective that is AND how you might need more rail eventually. Rush hour had a train there every ~2 minutes and they were still packed.

I mean they are much better, but this is only true to a point. You can't get better than 60-90s frequency per direction on a classic fully automated dual track line. Afterwards you need to add more tracks, or increase the length of the trains.

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> You can't get better than 60-90s frequency per direction on a classic fully automated dual track line.

Note that this is 40-60 trains per hour, and each Yamanote train holds 1724 people, giving a capacity of 69,000-100,000 passengers per hour per direction

A highway lane operating at peak capacity can carry fewer than 2000 vehicles per hour. If each vehicle held typical passenger loading of 2 passengers (average occupancy is actually lower in most cities), the yamanote line would need 17-25 highway lanes in each direction to replace one track in each direction (plus way more space for entering and exiting the highway than a subway station requires).

So while your fundamental point (train tracks have limits) is true, by that point a comparison with automobile infrastructure is truly absurd!

Oh of course, it's not even in the same league with extremely wasteful highways.

My point was just that tracks have limits too and at some point you need to add more of them / add more train cars / add new lines.

This can be seen in Paris where RER A was built in part to decongest line 1, which then resulted in both being heavily congested (RER A is one the most heavily used commuter rail line in Europe and the whole world). This led to the creation of line 14 to decongest the A and 1 inside of Paris, but it got congested too, so now there's also the RER E to decongest the 1, 14, A and B by taking over some trips between destinations that would have required doing a change 14+A or B+A.

Wow, I knew the difference was big, but not that big.

This made me think, how does this all compare to bikes? I found one study [1] which finds ~6500 bikes per hour for a 2m wide cycling path. That's actually much closer to a highway lane than I expected.

[1] https://fietsberaad.nl/CROWFietsberaad/media/Kennis/Bestande...

Bicycles aren't remotely as efficient as trains, which should be obvious really. Trains can carry a ton of people (literally, more like many, many tons! :-) ), at fairly high speed (talking about city trains/subways here, not bullet trains). At crowded times, people can be packed in quite densely, almost shoulder-to-shoulder. And this can all be done quite safely, with injuries and deaths astronomically uncommon if the train is operated and maintained properly.

Cycling has far less density, and far greater danger. It's easy to fall off a bike, or run into someone (pedestrian or cyclist), and it's even worse if there's cars around. Bikes are also quite slow compared to trains.

The advantages bikes have are:

1. flexibility: you can go most places by bicycle if the city doesn't hinder this too much by being too car-oriented. Trains only take you between far-apart stations, but a bike can take you the door of your destination. In places with good public transit and good bicycle support, it's very common for people to ride a bike to or from the train/subway station, and use the bicycle for the "last mile" instead of walking which is much slower.

2. small size: compared to cars, bikes take little space and so they don't need huge, wide roads, or even worse, giant parking lots. Here in Tokyo, lots of places have bicycle parking lots or garages, and it's staggering how many bicycles can fit into a space that only a handful of cars would be able to park in. And in places with no designated parking, it's common for people to just park their bike on the edge of the sidewalk, in a side alley, etc., things you can't do with a car.

So back to your 6500 bikes/hour figure: the problem with this kind of comparison is that it neglects parking. If everyone is driving in a car on a highway, they need a place to park, and putting parking for cars everywhere means everything must be spaced out much, much farther, which means everyone needs a car to get around. If no one has a car and everyone has a bicycle, then you don't need any car parking and bicycle parking takes very little space, so everything is now much closer together and you don't have to go nearly as far in the first place.

Of course, this doesn't even get into quality-of-life things like lack of pollution and noise, being able to actually see people's faces as you're out and about, etc.

Don't forget 3. Affordability!

Even a $1000 bike would pay itself off within a year versus train fares and it is possible to buy a reasonable used commuter bicycle for hundreds less than that. Cycling is def the most affordable form of transportation out there (aside from walking of course).

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).

> 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).

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.

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.

> 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).

>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.

The Yamanote is mostly quadruple-track, although the commuter line uses only two of those. Trains run every two minutes at peak hour, and each train has 11 carriages, giving the system ridiculous capacity.

the commuter line only uses two of those but this is a bit misleading because there are other parallel rail lines over much of its length running right alongside.

there used to be not as many, but the Yamanote was so overcrowded that they constructed additional pairs of tracks to reduce the amount of people who needed to change trains onto the Yamanote.

and yes they did. aside from the keihin touhoku line that's already running in parallel with yamanote line, JR East added a new track called ueno-tokyo line about 10 years ago. And the trains on the new lines are mostly 15-cars (with 2 double decker cars!). Note that for passengers travelling north-south they can also take the west route (going through shinjuku instead of tokyo), and there're also 3 parallel lines on the west. JR runs on narrow gauge which takes less space, and is cheaper to construct. Maybe this is one reason to make these expansion project fesible. https://en.wikipedia.org/wiki/Ueno%E2%80%93Tokyo_Line

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