In New York, two neighborhoods at the edge of the city have both subway and commuter rail service: Wakefield and Far Rockaway. Wakefield has 392 inbound weekday Metro-North boardings, and 4,955 weekday subway boardings. Far Rockaway has 158 riders (an average of boardings and alightings) and 4,750 subway boardings. Although both Wakefield and Far Rockaway are served by the 2 and A, which run express in Manhattan, those trains make many local stops farther out – in fact the 2 and A are the top two routes in New York for total number of stations – and are much slower than commuter rail: the 2 takes 50 minutes to get to Times Square while Metro-North gets to Grand Central within 25-30 minutes; the A takes about 1:05 to get to Penn Station, the LIRR about 55 minutes.
Vancouver, whose commuter rail service runs 5 daily roundtrips, all peak-hour, peak-direction, has a weekday ridership of 10,500. The Evergreen Line, duplicating the inner parts of the commuter rail service, is expected to get 70,000.
Caltrain, a service of intermediate quality between Vancouver’s peak-only trains and New York’s semi-frequent off-peak electrified service, has an intermodal station at Millbrae, which is now BART’s southern terminal. Millbrae has 5,970 BART exits per weekday versus 2,880 Caltrain boardings. And BART takes a circuitous route around the San Bruno Mountain and only serves San Francisco and the East Bay, while Caltrain takes a direct route to just outside the San Francisco CBD and serves Silicon Valley in the other direction.
The MBTA provides both subway and commuter rail service, with several intermodal stations: Forest Hills, Quincy Center, Braintree, Porter Square, Malden, JFK-UMass. In all cases, ridership levels on the subway are at least 30 times as high as on commuter rail. Rapid transit and commuter rail stations are close together at the edge of the Green Line’s D line, a former commuter line; the line’s outer terminus, Riverside, gets 2,192 weekday boardings, while the nearest commuter rail station, Auburndale, gets 301.
Across those systems and several more, such as Chicago’s Metra and Toronto’s GO Transit (no link, it’s private data), the commuter rail stations located within city limits, even ones not directly adjacent to a rapid transit station, usually get little ridership (there are some exceptions, such as Ravenswood on Chicago’s UP-N Line). The suburban stations beyond reasonable urban transit commute range are much busier.
Of course, this is just a North American problem. In Japan, where commuter rail and urban rapid transit are seamlessly integrated, people ride commuter rail even when the subway is an option. Consult this table of ridership by line and station for JR East lines in Tokyo: not only would any investigation of ridership on the main lines (e.g. Tokaido on PDF-page 1, Chuo on PDF-page 8) show that their ridership distribution is much more inner-heavy than in New York and Boston, but also stations with transfers to the subway can have quite a lot of riders. Nakano on the Chuo Line, at the end of Tokyo Metro’s Tozai Line, has 247,934 daily boardings and alightings, comparable to its subway traffic of 133,919 boardings.
Although my various posts about commuter rail industry practices focus partially on operating costs, this is not directly what makes people choose a slower subway over a faster commuter train. Rather, it’s a combination of the following problems:
1. Poor service to microdestinations. Rapid transit gets you anywhere; North American commuter rail gets you to the CBD. For people in Wakefield who are going anywhere but the immediate Grand Central or East 125th Street area, Metro-North is not an option. Station spacing is too wide, which means the choice of destinations even from a station that isn’t closed is more limited, and trains usually make just one CBD stop.
2. Poor transfers to other lines. The transfers usually require paying an extra fare and walking long distances from one set of platforms to another.
3. High fares. In the German-speaking world, and in Paris proper, fares are mode-neutral. It costs the same to ride the RER as the Metro, except for a handful of recent Metro extensions to the suburbs that postdate the RER, such as to La Defense. In Japan, JR East fares are comparable to subway fares, though there are no free transfers. In North America this is usually not the case: it costs much more to ride commuter rail than to ride a parallel subway or light rail line.
4. Low frequency. This is partly a result of low ridership based on the previous factors, partly a tradition that was never reformed, and partly a matter of very high operating costs. With low enough off-peak frequency (Wakefield and Far Rockaway are served hourly midday), commuter rail can achieve cost recovery similar to that of subways, and in some cities even surpass it. People who have no other options will ride hourly trains.
None of those problems is endemic to mainline rail. They’re endemic to North American mainline rail culture, and in some cases to labor practices. It’s all organization – it’s not a problem of either electronics or concrete, which means that the cost to the taxpayers of fixing it, as opposed to the political cost to the manager who tries to change the culture, is low.
The electronics and concrete do matter when it comes to building extensions – and this is where the ARC Alt G vs. Alt P debate comes from, among many others – but even commuter rail systems that do not need such extensions underperform. For example, Toronto does not need a single meter of commuter rail tunnel. Philadelphia, which already got most of the concrete it needs and partially fixed the microdestination problem, gets somewhat more commuter rail ridership in areas where people have alternatives, but frequency on the branches is still pitiful and inner-city stop spacing outside Center City is still too wide, leading to disappointing ridership.
Another way to think about it is that infrastructure should be used for everything, and not segregated into local transit and railroad super-highways that aren’t very accessible to locals. There are eight tracks connecting Manhattan directly with Jamaica, but the four used by the subway are far busier than the four used almost exclusively by suburbanites. Something similar is true of the Metro-North trunk, and some MBTA and Metra lines – the commuter rail infrastructure is redundant with rapid transit and gives very high nominal capacity, but in reality much of it is wasted. In this way, the mainline rapid transit concept including the Paris RER, the Germanic S-Bahn, and the Japanese commuter rail network, far outperforms, because it mixes local and regional traffic, creating service that everyone can use.