Paris vs Tokyo: the two different models for express commuter rail stopping patterns

A commuter at Tokyo's Shinjuku station. Image: Getty.

Many cities have large commuter rail networks, which function as urban rapid transit and extend into the suburbs. They use mainline rail rather than separate subway tracks, but are identical in other respects to conventional metro systems: urban stop spacing, frequency, and fares are all within the range of metro systems.

The biggest systems are in Japan, where Tokyo and Osaka carry the vast majority of their public transport passengers on commuter trains and not metro trains. In Europe, the biggest system is the Paris RER, while in the German-speaking world all major cities have S-Bahn networks.

But while the concepts are all broadly similar – mainline trains serving the suburbs share tracks in the core, so as to provide metro-like frequency – the stopping patterns vary.

First, some regional rail systems run express trains, whereas others are all local. The Munich and Berlin S-Bahns only have local trains. In contrast, the Paris RER and the Tokyo commuter rail network combine local and express trains – sometimes on four tracks, and sometimes on two, using the schedule to avoid conflicts.

Usually, systems that run express trains are bigger than systems that do not, but there are exceptions: Copenhagen's S-Train has express trains on most branches, and the Zurich S-Bahn has express trains on some lines as well.

On systems that are not modernised, express trains are especially common. That’s because the traditional function of commuter rail is to connect the suburbs with city center at rush hour; local services, connecting the suburbs with each other and not just with the city, are less important.

As a result, American commuter lines, even ones with very little ridership by European or Asian standards, generally have express trains: each stopping pattern might only get 1 or 2 trains per hour at rush hour. So do a few European branches, for example some of the outer commuter lines in Paris, not connected to the RER. Since these lines carry few riders, the important distinction is between different local and express patterns on busy lines that run frequently all day.

There isn't much to say about local trains, which (mostly) stop at every station. Express trains are more complex, and there are two ways to run them: one common in Paris, the other common in Tokyo. The Parisian model is to have long central segments with only two tracks, on which every train makes every stop. (In London, Crossrail is planned to follow the same pattern.) Tokyo’s railways have four-track segments, and express trains skip some stops even in the core.

Tokyo-style express trains may skip fewer stops in the centre than in dormitory communities, but they still skip even some central areas. On the eight-track main between Tokyo and Shinagawa Stations on the Tokaido Line, for example, the local Yamanote and Keihin-Tohoku Lines make all four intermediate stops; but the express Tokaido Main Line and Yokosuka Lines only make one intermediate stop, at Shimbashi. Central Tokyo stretches roughly between Tokyo Station and Shimbashi, and there is one station between them, Yurakucho, with transfers to four Tokyo subway lines. But in the judgement of rail planners, it made sense to skip this station, and for express trains to serve just one in every so many stops on the inner part of the line.

In Paris, no such thing service exists: the central tunnels only have two tracks, so it is hard to arrange local and express trains on them. Even on the few segments of the central network that have four tracks, such as part of RER C, there is no stop skipping. The transport authorities judge it best to have every commuter train make every stop within the city proper, which extends about 5 km out of the center.

Conversely, in the suburbs, Paris does mix some local and express trains on two tracks: the RER B runs 12 trains per hour off-peak – just enough room for trains which run non-stop between Gare du Nord and Charles-de-Gaulle Airport, and some express trains in the southern suburbs.

The Parisian approach ensures that the RER can function as high-frequency trunk lines within the city proper. The RER A averages a stop per 2.5 km on the central trunk, and the RER B and C a stop every 1.2-1.3 km (the other two RER lines, the D and E, only make three city stops each). The Metro averages a stop every 500 meters, of course – but nonetheless, 1.2-1.3 km is well within the range for international metro systems, comparable to the spacing of stations on the London Underground. The central Crossrail trunk will average a stop every 1.6 km – wider than the Underground but not much more so.

In Tokyo, of course, the commuter rail frequency in the core is even higher, since the inner lines are all at least four-tracked. But farther out, there are express and local trains mixed on two tracks, with timed overtakes, using the legendary punctuality of Japanese railways to schedule trains to avoid conflicts. The result is that the express routes have quite wide stop spacing, which permits higher speeds, approaching 60 km/h on the Tokaido and Tohoku Main Lines.


A smaller city, with trunk lines not as full to capacity as in Tokyo, Paris, or London, could mix local and express trains even at rush hour. In Tokyo, local and express trains are mixed on some lines on the shoulders of rush hour (but not at rush hour, when trains arrive every 2 minutes); it is unclear what the absolute upper limit of this system would be, but it appears to be in the range of 15-20 trains per hour. In cities without Japanese punctuality, the limit is about 12 trains per hour: a local train and an express train each coming every 10 minutes, with an overtake every 6-8 stations.

Such cities have a choice. The Paris approach works very well for Paris, and the Tokyo approach works very well for Tokyo. There is always a tradeoff in mass transit between narrow stop spacing for service to more places, and wide stop spacing for higher average speed.

The two different approaches for commuter rail express stopping patterns display a related tradeoff, between higher frequency to all stations and higher average speed at express stations. Which of the two approaches is better depends on local factors. These include city size and density (more sprawl encourages the faster Tokyo approach, more density encourages the more frequent Paris approach); punctuality (better punctuality makes mixing local and express trains on two tracks easier); and how important it is that suburban commuters be able to reach every urban station, rather than just a few major stations.

There is no inherent better choice. The tradeoff is not that one option is more beneficial but more expensive, but rather that the two options have different benefit levels, depending on local conditions.

Those conditions can vary widely between cities, even in the same country. A smaller French or British city might find that its home and job distribution makes the Tokyo approach better, and a smaller Japanese city might find that the Paris approach works better for it.

Cities anywhere might even find that the German approach of not having any express trains works best. This means that planners should consider all stopping patterns, and not just default to what is familiar from nearby cities.

Alon Levy blogs at Pedestrian Observations and tweets as @alon_levy.

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Was the decline in Liverpool’s historic population really that unusual?

A view of Liverpool from Birkenhead. Image: Getty.

It is often reported that Liverpool’s population halved after the 1930s. But is this true? Or is it a myth?

Often, it’s simply assumed that it’s true. The end. Indeed, proud Londoner Lord Adonis – a leading proponent of the Liverpool-bypassing High Speed 2 railway, current chair of the National Infrastructure Commission, and generally a very influential person – stood on the stairs in Liverpool Town Hall in 2011 and said:

“The population of Liverpool has nearly halved in the last 50 years.”

This raises two questions. Firstly, did the population of the City of Liverpool really nearly halve in the 50 year period to 2011? That’s easy to check using this University of Portsmouth website – so I did just that (even though I knew he was wrong anyway). In 2011, the population of the City of Liverpool was 466,415. Fifty years earlier, in 1961, it was 737,637, which equates to a 37 per cent drop. Oops!

In fact, the City of Liverpool’s peak population was recorded in the 1931 Census as 846,302. Its lowest subsequent figure was recorded in the 2001 Census as 439,428 – which represents a 48 per cent decline from the peak population, over a 70 year period.

Compare this to the population figures for the similarly sized City of Manchester. Its peak population also recorded in the 1931 Census as 748,729, and its lowest subsequent figure was also recorded in the 2001 Census, as 392,830. This also represents a 48 per cent decline from the peak population, over the same 70 year period.

So, as can be seen here, Liverpool is not a special case at all. Which makes me wonder why it is often singled out or portrayed as exceptional in this regard, in the media and, indeed, by some badly briefed politicians. Even London has a similar story to tell, and it is told rather well in this recent article by a Londoner, for the Museum of London. (Editor’s note: It’s one of mine.)

This leads me onto the second question: where have all those people gone: London? The Moon? Mars?

Well, it turns out that the answer is bit boring and obvious actually: after World War 2, lots of people moved to the suburbs. You know: cars, commuter trains, slum clearance, the Blitz, all that stuff. In other words, Liverpool is just like many other places: after the war, this country experienced a depopulation bonanza.


So what form did this movement to the suburbs take, as far as Liverpool was concerned? Well, people moved and were moved to the suburbs of Greater Liverpool, in what are now the outer boroughs of the city region: Halton, Knowsley, St Helens, Sefton, Wirral. Others moved further, to Cheshire West & Chester, West Lancashire, Warrington, even nearby North Wales, as previously discussed here.

In common with many cities, indeed, Liverpool City Council actually built and owned large several ‘New Town’ council estates, to which they moved tens of thousands of people to from Liverpool’s inner districts: Winsford in Cheshire West (where comedian John Bishop grew up), Runcorn in Halton (where comedian John Bishop also grew up), Skelmersdale in West Lancashire, Kirkby in Knowsley. There is nothing unique or sinister here about Liverpool (apart from comedian John Bishop). This was common practice across the country – Indeed, it was central government policy – and resulted in about 160,000 people being ‘removed’ from the Liverpool local authority area.

Many other people also moved to the nearby suburbs of Greater Liverpool to private housing – another trend reflected across the country. It’s worth acknowledging, however, that cities across the world are subject to a level of ‘churn’ in population, whereby many people move out and many people move in, over time, too.

So how did those prominent images of derelict streets in the inner-city part of the City of Liverpool local authority area come about? For that, you have to blame the last Labour government’s over-zealous ‘Housing Market Renewal Initiative’ (HMRI) disaster – and the over enthusiastic participation of the then-Lib Dem controlled city council. On the promise of ‘free’ money from central government, the latter removed hundreds of people from their homes with a view to demolishing the Victorian terraces, and building new replacements. Many of these houses, in truth, were already fully modernised, owner-occupied houses within viable and longstanding communities, as can be seen here in Voelas Street, one of the famous Welsh Streets of Liverpool:

Voelas Street before HMRI implementation. Image: WelshStreets.co.uk.

The same picture after HMRI implementation Image: WelshStreets.co.uk. 

Nonetheless: the council bought the houses and ‘tinned them up’ ready for demolition. Then the coalition Conservative/Lib Dem government, elected in 2010, pulled the plug on the scheme. 

Fast forward to 2017 and many of the condemned houses have been renovated, in a process which is still ongoing. These are over-subscribed when they come to market, suggesting that the idea was never appropriate for Liverpool on that scale. 

At any rate, it turns out that the Liverpool metropolitan population is pretty much the same as it was at its peak in 1931 (depending where the local borough boundaries are arbitrarily drawn). It just begs the question: why are well educated and supposedly clever people misrepresenting the Liverpool metropolis, in particular, in this way so often? Surely they aren’t stupid are they?


And why are some people so determined to always isolate the City of Liverpool from its hinterland, while London is always described in terms of its whole urban area? It just confuses and undermines what would otherwise often be worthwhile comparisons and discussions. Or, to put it another way: “never, ever, compare apples with larger urban zones”.

In a recent Channel 4 documentary, for example, the well-known and respected journalist Michael Burke directly compared the forecast population growths, by 2039, of the City of Liverpool single local authority area against that of the combined 33 local authority areas of Greater London: 42,722 versus 2.187,708. I mean, what bizarre point is such an inappropriate comparison even trying to make? It is like comparing the projected growth of a normal sized-person’s head with the projected growth of the whole of an obese person, over a protracted period.

Having said all that, there is an important sensible conversation to be had as to why the populations of the Greater Liverpool metropolis and others haven’t grown as fast as maybe should have been the case, whilst, in recent times, the Greater London population has been burgeoning. But constantly pitching it as some sort of rare local apocalypse helps no one.

Dave Mail has declared himself CityMetric’s Liverpool City Region correspondent. He will be updating us on the brave new world of Liverpool City Region, mostly monthly, in ‘E-mail from Liverpool City Region’ and he is on twitter @davemail2017.