In New York, the de Blasio administration has been spending considerable political capital pushing for a $2.5 billion light rail line connecting Astoria and the Brooklyn waterfront south to Sunset Park. There has been a lot of criticism from good transit advocates about implementation – namely, it’s unclear there will be free transfers to the subway and buses, in order to avoid having to share turf with the state-owned MTA – but also of the basic concept, which is not the biggest transit priority in the region, or for matter the twentieth. In comments and on social media, I’ve seen a few wrong arguments made in support of waterfront light rail and similar bad investments over and over, and I’d like to go in some detail into where cities should and should not build such lines.
The principles below are based on various oppositions: first world versus third world, fast versus slow growth, subway versus no subway. I think a good meta-principle is that if the presence of a certain factor is an argument in favor of a specific solution, then its absence should be an argument against that solution. For instance, if high wages are an argument in favor of rail and against bus rapid transit, then low wages should be an argument in favor of bus rapid transit; this principle makes me wonder what Addis Ababa was thinking when it built light rail instead of BRT, while at the same time thinking very little of American cities that make the decision that Addis Ababa should have made. The upshot of the meta-principle is that many of the guidelines that work in New York could work in very different cities, in reverse.
1. New York is a mature first-world city with low population growth; it should build transit exclusively or almost exclusively based on current population and transportation patterns, and not attempt to engage in development-oriented transit. The upzoning the city engages in is too small compared to current population, and cannot justify anything of the magnitude of Vancouver’s Expo Line, which was built simultaneously with Metrotown and the New Westminster offices around the train stations. And even Vancouver cannot reasonably expect the growth rates of various third-world cities with annual population growth rates in the vicinity of 5% and even higher per capita income growth rates.
2. Rail bias is approximately the same on all routes. Routes with many turns and narrow roads have unusually slow buses, but they’ll also have unusually slow surface rail. Rapid transit does have the ability to avoid the extra traffic jams coming from such alignments, and this is especially important in cities where the main street is not the same as the nearby wide boulevard, but this is not what’s under discussion in New York. Yes, de Blasio’s proposed light rail line would get more riders than the buses on segments of the route in question are getting now; the same would be true of any number of light rail routes paralleling the busiest buses in the city.
3. In a city with a subway, the best light rail routes are the ones that don’t make sense as subway extensions. Of the three busiest buses in New York, two make sense as subway lines, so there’s no point building light rail and only later a subway: the M15, on First and Second Avenues, and the B46, on Utica. In contrast, the third route, the Bx12 on Fordham, is crosstown, and cannot reasonably be an extension of any subway line, so it would be a strong light rail corridor. The same can be said of Main Street in Queens, between Flushing and Jamaica; and 14th and 86th Streets in Manhattan, where the M14 and M86 are the busiest surface routes in the US in terms of riders per kilometer, well ahead of the Boston Green Line (they both have about 8,000, and the Green Line 6,000). Of note, 14th Street already hosts the L, but a branch going on Avenue D is far from the subway, and the street is so well-trafficked that despite slower-than-walking bus speeds, that arguably light rail makes sense there even with the subway.
4. As soon as a project is judged as not a top priority, it’s best to think of how useful it is once the top priorities are built. In the case of New York, let us zoom in on Brooklyn’s top two circumferential buses, the
B4 B6 and B35. Triboro RX is a higher priority than turning these routes into light rail, and once it’s in place, how much demand is there really going to be for them? It would be faster to take the subway and connect to Triboro, except at very short distances, where speeding up surface traffic is less useful.
In New York, excluding the somewhat special cases of 14th and 86th Streets, I’d say there are three light rail networks that make sense: one in the Bronx, one in Brooklyn, and one in Queens. The Bronx network involves taking the borough’s most frequent buses and turning them into light rail routes: the Bx12 on Fordham as noted above, but also the Bx1/2 on Grand Concourse (like 14th Street, hosting both a subway and a very busy bus route), the Bx19 on Southern and 145th, the Bx15 on Third, and a route on Tremont combining the Bx36 and the Bx40/42. These routes roughly form a grid, each has at least 30,000 weekday riders, and none is SBS except the Bx12. In this case, light rail should really be thought of as the next step after publishing a frequent grid map based on these routes and equipping the entire city bus fleet with off-board fare collection.
In Queens, there’s less room for a grid – the borough has street grids, but it really is based on several old centers, with major roads connecting them. The strongest routes are the ones that cannot reasonably be subway extensions, because they’re too circumferential; in turn, the strongest subway extension, i.e. Northern, is not a major bus route, because it’s close enough to the Queens Boulevard subway that people instead take the subway, which is overcrowded. Of the strong surface transit routes, the corridor with the highest ridership takes in several bus routes between Flushing and Jamaica; Main Street is the most important route, but potentially there’s room both there and on the second route, Kissena-Parsons. Other potential light rail routes radiate from Flushing and Jamaica, in directions not well-served by the subway and the LIRR, or even west on Queens Boulevard to help serve the gap in subway coverage between the 7 and the Queens Boulevard Line and relieve the subway lines.
Brooklyn is the most interesting. The main missing pieces in subway coverage in Brooklyn are good subway extensions: Triboro, Utica, Nostrand. With those in place, the only real gaps are Flatbush, and some route serving Red Hook. Possibly service to the Navy Yard may be desirable, but the area is not very well-developed right now, and the buses serving it have low ridership. Those are two or three routes radiating out of the same center in Downtown Brooklyn, which makes it tempting to not only build light rail on them, but also send it over the Brooklyn Bridge to City Hall. This would be like the subway-surface lines in Boston and San Francisco, where one underground trunk splits into several at-grade branches, except that in this case the trunk would be elevated rather than underground. It’s not worth building by itself, but the possibility of leveraging Brooklyn Bridge lanes for several light rail lines may make the ridership per unit of cost pencil out.
The common factor to all of these possibilities is that they are not meant for signature development areas that the city is targeting. Maybe there’s some new development there, but the focus is on improving public transit services to existing residents, who either are riding very slow buses or have given up on public transit because of the inconvenience. It can be marketed as an improvement in transit, but cannot really be sold as part of a plan to revitalize the Brooklyn waterfront. It’s about day-to-day governing, whereas the administration is interested in urban renewal schemes, which are rarely good transit.
In New York, the MTA has consistent guidelines for how frequently to run each subway route, based on crowding levels. The standards are based on crowding levels at the point of maximum crowding on each numbered or lettered route. Each line is designed to have the same maximum crowding, with different systemwide levels for peak and off-peak crowding. While this approach is fair, and on the surface reasonable, it is a poor fit for New York’s highly branched system, and in my view contributes to some of the common failings of the subway.
Today, the off-peak guidelines call for matching frequency to demand, so that at the most crowded, the average train on each route has 25% more passengers than seats. Before the 2010 service cuts, the guidelines had the average train occupied to exact seating capacity. At the peak, the peak crowding guidelines are denser: 110 passengers on cars on the numbered lines, 145 on shorter (60’/18 m) cars on the lettered lines, 175 on longer (75’/23 m) cars on the lettered lines. There’s a minimum frequency of a train every 10 minutes during the day, and a maximum frequency at the peak depending on track capacity. When the MTA says certain lines, such as the 4/5/6, are operating above capacity, what it means is that at maximum track capacity, trains are still more crowded than the guideline.
In reality, guideline loads are frequently exceeded. Before the 2010 service cuts, many off-peak trains still had standees, often many standees. Today, some off-peak trains are considerably fuller than 25% above seated capacity. In this post, I’d like to give an explanation, and tie this into a common hazard of riding the subway in New York: trains sitting in the tunnels, as the conductor plays the announcement, “we are delayed because of train traffic ahead of us.”
The key takeaway from the system is that frequency at each time of day is calculated separately for each numbered or lettered route. Even when routes spend extensive distance interlined, as the 2/3 and 4/5 do, their frequencies are calculated separately. As of December 2014, we have the following headways, in minutes:
|Line||AM peak||Noon off-peak||PM peak|
Consider now the shared segments between the various lines. The 4 comes every 4.5 minutes in the morning peak, and the 5 every 5 minutes. There is no way to maintain even spacing on both lines with these headways: they share tracks for an extensive portion of their trip. Instead, the dispatchers move trains around to make sure that headways are as even as possible on both the shared trunk segments and the branches, but something has to give. In 45 minutes, there are ten 4s and nine 5s. Usually, on trunk lines with two branches, trains alternate, but here, it’s not possible to have a perfect alternation in which each 4 is followed by a 5 and each 5 is followed by a 4. There is bound to be a succession of two 4s: the second 4 is going to be less crowded than the guideline, and the following 5 is going to be more crowded.
It gets worse when we consider the extensive reverse-branching, especially on the lettered lines. For example, on its northbound journey, the Q initially does not share tracks with any line; then it shares tracks with the B, into Downtown Brooklyn; then it crosses into Manhattan sharing tracks with the N; then it again shares tracks with no other route, running express in Manhattan while the N runs local; then it shares tracks with the N and R into Queens; and then finally it shares tracks with the N in Queens. It is difficult to impossible to plan a schedule that ensures smooth operations like this, even off-peak, especially when the frequency is so variable.
Concretely, consider what happens when the Q enters Manhattan behind an N. Adequate separation between trains is usually 2 minutes – occasionally less, but the schedule is not robust to even slight changes then. To be able to go to Queens ahead of the N, the Q has to gain 4 minutes running express in Manhattan while the N runs local. Unfortunately, the Q’s express jaunt only skips 4 stations in Manhattan, and usually the off-peak stop penalty is only about 45 seconds, so the Q only gains 3 minutes on the N. Thus, the N has to be delayed at Herald Square for a minute, possibly delaying an R behind it, or the Q has to be delayed 3 minutes to stay behind the N.
In practice, it’s possible to schedule around this problem when schedules are robust. Off-peak, the N, Q, and R all come every 10 minutes, which makes it possible to schedule the northbound Q to always enter Manhattan ahead of the N rather than right behind it. Off-peak, the services they share tracks with – the B, D, and M – all come every 10 minutes as well. The extensive reverse branching still makes the schedule less robust than it can be, but it is at least possible to schedule non-conflicting moves. (That said, the M shares tracks with the much more frequent F.) At the peak, things are much harder: while the N, Q, and R have very similar headways, the D is considerably more frequent, and the B and M considerably less frequent.
I believe that this system is one of the factors contributing to uneven frequency in New York, with all of the problems it entails: crowding levels in excess of guidelines, trains held in the tunnel, unpredictable wait times at stations. Although the principle underlying the crowding guidelines is sound, and I would recommend it in cities without much subway branching, in New York it fails to maintain predictable crowding levels, and introduces unnecessary problems elsewhere.
Instead of planning schedules around consistent maximum crowding, the MTA should consider planning schedules around predictable alternation of services on shared trunk lines. This means that, as far as practical, all lettered lines except the J/Z and the L should have the same frequency, and in addition the 2/3/4/5 should also have the same frequency. The 7 and L, which do not share their track or route with anything else, would maintain the present system. The J/Z, which have limited track sharing with other lines (only the M), could do so as well. The 1 and 6 do not share tracks with other lines, but run local alongside the express 2/3 and 4/5. Potentially, they could run at exactly twice the frequency of the 2/3/4/5, with scheduled timed local/express transfers; however, while this may work for the 6, it would give the 1 too much service, as there is much more demand for express than local service on the line.
To deal with demand mismatches, for example between the E/F and the other lettered lines, there are several approaches, each with its own positives and negatives:
– When the mismatch in demand is not large, the frequencies could be made the same, without too much trouble. The N/Q/R could all run the same frequency. More controversially, so could the 2/3/4/5: there would be more peak crowding on the East Side than on the West Side, but, to be honest, at the peak the 4 and 5 are beyond capacity anyway, so they already are more crowded.
– Some services could run at exactly twice the frequency of other services. This leads to uneven headways on the trunks, but maintains even headways on branches. For example, the A’s peak frequency is very close to exactly twice that of the C, so as they share tracks through Lower Manhattan and Downtown Brooklyn, they could alternate A-C-A-empty slot.
– Services that share tracks extensively could have drastic changes in frequency to each route, preserving trunk frequency. This should be investigated for the E/F on Queens Boulevard: current off-peak frequency is 8 trains per hour each, so cutting the E to 6 and beefing the F to 12 is a possibility.
– Service patterns could be changed, starting from the assumption that every lettered service runs every 10 minutes off-peak and (say) 6-7 minutes at the peak. If some corridors are underserved with just two services with such frequency, then those corridors could be beefed with a third route: for example, the Queens Boulevard express tracks could be supplanted with a service that runs the F route in Jamaica but then enters Manhattan via 53rd Street, like the E, and then continues either via 8th Avenue like the E or 6th Avenue like the M. Already, some peak E trains originate at Jamaica-179th like the F, rather than the usual terminus of Jamaica Center, which is limited to a capacity of 12 trains per hour.
– The service patterns could be drastically redrawn to remove reverse branching. I worked this out with Threestationsquare in comments on this post, leading to a more elegant local/express pattern but eliminating or complicating several important transfers. In particular, the Broadway Line’s N/Q/R trains could be made independent of the Sixth Avenue trains in both Queens and Brooklyn, allowing their frequencies to be tailored to demand without holding trains in tunnels to make frequencies even.
For the lettered lines, I have some affinity for the fourth solution, which at least in principle is based on a service plan from start to finish, rather than on first drawing a map and then figuring out frequency. But it has two glaring drawbacks: it involves more branching than is practiced today, since busy lines would get three services rather than two, making the schedule less robust to delays; and it is so intertwined with crowding levels that every major service change is likely to lead to complete overhaul of the subway map, as entire routes are added and removed based on demand. The second drawback has a silver lining; the first one does not.
I emphasize that this is more a problem of reverse branching than of conventional branching. The peak crowding on all lines in New York, with the exception of the non-branched 7 and 1, occurs in the Manhattan core. Thus, if routes with different colors never shared tracks, it would not be hard to designate a frequency for each trunk route at each time of day, without leading to large mismatches between service and demand. In contrast, reverse branching imposes schedule dependencies between many routes, to the point that all lettered routes except the L have to have the same frequency, up to integer multiples, to avoid conflicts between trains.
The highly branched service pattern in New York leads to a situation in which there is no perfect solution to train scheduling. But the MTA’s current approach is the wrong one, certainly on the details but probably also in its core. It comes from a good place, but it does not work for the system New York has, and the planners should at least consider alternatives, and discuss them publicly. If the right way turns out to add or remove routes in a way that makes it easier to schedule trains, then this should involve extensive public discussion of proposed service maps and plans, with costs and benefits to each community openly acknowledged. It is not good transit to maintain the current scheduling system just because it’s how things have always worked.
Two years ago, when Elon Musk first proposed Hyperloop as a faster, cheaper, and more entrepreneurial alternative to California High-Speed Rail, I explained in depth what was wrong with the proposal. The curve radii were too tight for passenger comfort, and any attempt to fix them would require more expensive civil infrastructure. In general, the cost estimates in the plan were laughably low. Musk has moved on, but another team has been trying to build the system. It is planning to build a test track in the next three years, a distance of 8 km, for $150 million.
Let us analyze these costs. The per-km cost of this scheme is about $19 million, which if costs don’t run over is reasonable for HSR flat terrain, if anything a bit low. California HSR’s Central Valley segments, in more urbanized areas, are about $24-27 million/km, ex-electrification and systems (which don’t add much). This, in principle, suggests the system could be built for about the same cost as conventional HSR. Of course, it’s already far more expensive than Musk’s original estimate of $6 billion for about 650 km (including tunnels), but it still sounds like a good deal – in theory.
In practice, I’d like to go back to my often-quoted sentence in my post from two years ago, that Hyperloop would be a barf ride. The plan is to run capsules at their full speed, but only when empty. Tests with passengers would be restricted to 160 mph, or about 260 km/h. If the picture in the article describing the test track is accurate, the turn looks like its radius is perhaps 800 meters. Passengers can’t ride through this at very high speed. Even at 260 km/h, it requires full canting, and will make passengers feel noticeable extra gravitational push, about 0.2 g.
The importance of this is that any attempt to build tracks at higher speed will run into problems with both horizontal and vertical curves very quickly. The picture depicts sleek viaducts in empty land; imagine much taller viaducts, to allow the track to curve more gently than the terrain. Once the terrain becomes problematic, as it does on the approaches to the mountain crossings from the Central Valley to both the Los Angeles Basin and the San Francisco Bay Area, costs go up. This is true for any mode of transportation, up to and including mountain roads with hairpin turns, but the higher the speed, the larger the cost differential. In this situation, 4 km horizontal curve radii and 20 km vertical curve radii (about absolute minimum for conventional HSR) are expensive; 20 km horizontal curves and 230 km vertical curves are far more so. And within the urban areas, the inability of the system to leverage legacy rail tracks forces expensive urban viaducts.
Two recent news items have driven home the point that American construction costs are out of control. The first is the agreement between the federal government and the states of New York and New Jersey to fund the Gateway project, at a cost of $20 billion. The second is the release of more detailed environmental impact studies for high-speed rail on the Northeast Corridor; I previously expressed tepidly positive sentiment toward the NEC Future concept, but now there are concrete cost projections: the only full HSR option, Alternative 3, is projected to cost $290 billion. As Stephen Smith noted on Twitter, Alternative 3 is twice as expensive per km as the mostly underground Chuo Shinkansen maglev. As such, I am going to ignore other issues in this post, such as whether to serve Hartford on the mainline or not: they are real issues, but are secondary concerns to the outrageous cost figures.
Although both Gateway and NEC Future have extreme costs – too high for me to be able to support either project – the causes of those high costs are different. Gateway includes not just a new tunnel across the Hudson but also substantial unnecessary scope in Penn Station South; however, I suspect that even if the scope is pared down to the minimum required to provide four tracks from Newark to New York, the budget would still be very high. The bare Gateway tunnel (including Penn South) is to my understanding $14-16 billion; the maximum cost that can be justified by the extra ridership, unless additional operating improvements (which can be done today) are in place, is about $7 billion. As with Second Avenue Subway, there is a real problem of high unit costs. I emphasize that there is too much scope in Gateway, but the scope alone cannot explain why 5 km of tunnel cost many billions, when expensive non-US projects such as Crossrail top at a billion dollars per km and the geologically more complex Marmaray tunnel cost (in PPP terms) about $400 million per km.
The situation with NEC Future is different, in two ways. First, if Gateway cuts a zero from the budget, I will consider it a solid project, perhaps even an inexpensive one given the wide river crossing. (For reference, in 2003 the projected cost was $3 billion). In contrast, if NEC Future cuts a zero from its budget, I will still consider it too expensive – perhaps worth it because of the benefits of HSR, but certainly too high to be built without further inquiry. $29 billion for 720 km is justified for a line with a fair amount of tunneling and entirely greenfield construction, whereas the NEC has long segments that are already nearly ready for HSR and requires very little tunneling.
But second, and more importantly, NEC Future’s unit costs are not high. Read appendix B.06, which discusses cost: on PDF-p. 28 it breaks down cost by item, and other than the tunnels, which at $400-500 million per km are several times as expensive as intercity rail tunnels usually are, the infrastructure items’ per-km costs are reasonable. And the NEC doesn’t require much tunneling in the first place: Connecticut may be hilly, but HSR can climb 3.5% grades and ride on top of the hills, and only in Bridgeport is tunneling really necessary. Make it perhaps 5 km of required tunneling, all around Bridgeport. When I said $10 billion would build full-fat HSR on the NEC, I assumed $200-250 million per km for the Bridgeport tunnel. I also assumed $750 million for new tunnels in Baltimore, whose cost has since risen to $4 billion in part due to extra scope (4 tracks rather than 2). So 2 extra billions come from more expensive tunneling, and 278 extra billions come from bloated scope. Perhaps a subset of the 278 comes from high unit costs for systems and electrification, but these are not the main cost drivers, and are also quite easy to copy from peer developed countries. In the rest of this post, I will document some of the unnecessary scope. I emphasize that while Alternative 3 is the worst, the cost projection for Alternative 1, at $50 billion, is still several times the defensible cost of improvements.
Let us turn to chapter 4, the alternatives analysis, and start on PDF-p. 54. Right away, we see the following wasteful scope in Alternative 2:
- Full four-tracking on the Providence Line, instead of strategic overtakes as detailed here.
- A bypass of the Canton Viaduct, which at a radius of 1,746 meters imposes only a mild speed restriction on trains with E5 and Talgo tilt capability, 237 km/h.
- An entirely new tunnel from Penn Station to Sunnyside, adding a third East River tunnel even though the LIRR is not at capacity now, let alone after East Side Access opens.
- A tunnel under Philadelphia, so as to serve the city at Market East rather than 30th Street Station.
- Two new HSR-dedicated tracks in New Jersey parallel to the NEC, rather than scheduling commuter trains on existing local tracks as detailed here.
- Two new HSR-dedicated tracks alongside much of the New Haven Line, even in areas where the existing alignment is too too curvy.
- Extensive tunneling between New Haven and Providence (see PDF-pp. 69-70 and 75), even in Alternative 1, even though HSR trains can climb the grades on the terrain without any tunnels outside the Providence built-up area if the tracks go west.
Alternative 2 also assumes service connecting New Haven, Hartford, and Providence, which I do not think is the optimal alignment (it’s slightly more expensive and slower), but is defensible, unlike the long proposed tunnels under Philadelphia, totaling around 30 km. The overall concept is also far more defensible than the tunnel-heavy implementation.
Alternative 3 adds the following unnecessary scope (see PDF-pp. 58 and 76-83):
- Full six-tracking between New York and Philadelphia and between Baltimore and Washington.
- Tunnel-heavy alignment options bypassing the New Haven Line, including inland options via Danbury or a tunnel across the Long Island Sound.
- The new Baltimore tunnels are longer and include a new Baltimore CBD station, where the existing station is at the CBD’s periphery.
- If I understand correctly, new platforms at New York Penn Station under the existing station.
- Tunnels under the built-up area of Boston.
According to the cost breakdown, at-grade track costs $20 million per km, embankments cost $25 million per km, elevated track costs about $80 million per km, and tunnels cost $400 million per km. When I draw my preferred alignments, I assume the same cost elements, except tunnels are cheaper, at $200 million per km. (I also add 20% for overheads on top of these base costs, whereas these documents add contingency on top of that.) This should bias the NEC Future toward above-ground options.
Instead, look at the maps in appendix A. Alternative 3 is PDF-pp. 76-81. The options for getting out of the New York urban area include an almost entirely tunneled inland alignment, and a tunnel under the Long Island Sound; making small compromises on trip time by using the New Haven Line, and making up time elsewhere by using better rolling stock, is simply not an option to the planners.
Let’s go back to Gateway now. Although the cost premium there is not as outrageous as for NEC Future, it is a good case study in what the US will fund when it thinks the project is necessary and when there is sufficient lobbying. Paris has the political will to spend about $35 billion on Grand Paris Express, and London is spending $22 billion on Crossrail and is planning to spend much more on Crossrail 2. Between Second Avenue Subway, the 7 Extension, Fulton Street Transit Center, the PATH terminal, East Side Access, and now Gateway, New York is planning to have spent $43 billion on public transit by the middle of next decade. And now people are talking about Second Avenue Subway Phase 2. The political will to build both rapid transit and HSR in the US exists; the government spends tens of billions on it. But due to poor cost effectiveness, what the US gets for its money is almost nothing.
The $20 billion that the federal government and both states are willing to set on fire for Gateway prove that, were there a plan to build HSR so that trains would go between Boston and Washington in three and a half hours on a budget of $10-15 billion, it would be funded. This is not a marginal case, where the best plan still elicits groans from anti-tax conservatives: those conservatives ride trains between New York and Washington and want them to be faster. Instead, it is purely about excessive costs. Gateway’s $20 billion could build the tunnel and also full HSR on the NEC, and the $290 billion that NEC Future wants to burn on HSR could build nearly a complete national HSR network, serving most metro areas above 1 million people. It’s no longer a question of political will; it’s purely a question of cost control. 95% cost savings are possible here, and this is the only thing advocates for better intercity rail in the US should be focusing on.
The Long Island Railroad’s timetable is a mess. There is too little off-peak service, especially at the urban stations. At the peak, there is more service, but the service pattern is inscrutable. The Babylon Branch runs a skip-stop pattern in which trains make three stops, skip the next three, and then make the three after them. The pattern of which branch east of Jamaica is sent to which city terminal (Penn Station, Flatbush/Atlantic, or occasionally Hunterspoint) is inconsistent; passengers generally get timed cross-platform transfers at Jamaica, but the frequent interlacing of trains introduces a lot of dependency between different branches in the schedule, reducing reliability. Worst, the Main Line runs trains one-way, so for an hour in the peak, there is no off-peak service. As expected, reverse-peak ridership is minimal, even though there’s a fair number of jobs within a comfortable walk of Mineola. In this post, I am going to discuss how to improve the schedules.
The main tool I will use is a map of LIRR line speed zones. This was made by Patrick O’Hara, of the invaluable but now taken-offline blog The LIRR Today. I emphasize that Patrick does not endorse my plan to eliminate one-way service, on the grounds that it would unacceptably add to the travel time for conventional peak trips from Hicksville and points east to Penn Station. However, using the map and some data about rolling stock performance, I am going to show that LIRR schedules are so padded that improvements to reliability via simpler scheduling can reduce trip times significantly, more than making up for additional trip times to the elimination of most express runs.
First, let us compute technical trip times. In Boston, I compute these by looking at the acceleration rate of the FLIRT, but New York has passable rolling stock already, which means that modernization does not require full replacement of the fleet. This means we should use the specs of the M7: 13.9 kilowatts per ton (FLIRT: 21.7 maximum, 16.7 continuous), and an initial acceleration rate of 0.9 m/s^2 (FLIRT: 1.2). Assuming no air resistance, this means the theoretical acceleration penalty to 130 km/h, the speed over most of the electrified LIRR main lines, is 23 seconds. Judging by the difference between theoretical and actual FLIRT acceleration performance, the actual penalty is about 26 seconds. The deceleration penalty is 19 seconds, for a total of 45. Up to a speed of 100 km/h, the acceleration penalty is 17 seconds and the deceleration penalty is 13 seconds, for a total of 30.
Let us take dwell times to be 30 seconds. With reasonably wide doors at the quarter points and level boarding, it should not be difficult for the LIRR to hold to this standard. Actual dwells appear to be about 40-50 seconds, but are in the context of considerable schedule padding, as we will see. I am going to round speeds up from mph to km/h, so 80 mph will be rounded to 130 km/h, and 60 mph to 100 km/h; the numbers are close, and when I compute curve speeds, the total equivalent cant seems very low, such that large speed increases are possible. However, I am going to stick to the speed map, only changing to km/h for ease of calculation. Including dwell time, the stop penalty in 130 km/h territory is 75 seconds, and the stop penalty in 100 km/h territory is 60 seconds.
Of note, the actual stop penalties we see on LIRR schedules are larger, on the order of 100 seconds. Part of it is the padding again, but part of it is that LIRR trains do not accelerate as fast as they can; the LIRR derated its trains, limiting their acceleration to about 0.45 m/s^2 to reduce the electric current. This can and should be reversed. If it is not, the acceleration penalty is 40 seconds to 130 km/h and 31 seconds to 100 km/h, while the deceleration penalty, unaffected by the change to maximum acceleration, remains the same; overall, this slows trains by about 15 seconds per stop.
East of Jamaica, there are almost no slow zones on either the Main Line or the Babylon Branch. Hicksville’s 65 km/h zone slows trains that stop at Hicksville by about 30 seconds (even a few hundred meters from the station, trains could go faster if the line speed were higher). The curve between Bethpage and Farmingdale is worth 15 seconds. The slowdown in the interlocking at the junction with the Hempstead Line adds 5 seconds. The slowdowns in Jamaica add 35 seconds east of Jamaica, and 55 west of Jamaica, both for stopping trains. On the Babylon Branch, there are a few restrictions in the 80-110 km/h range, worth in total about 70 seconds; Babylon itself is in 100 km/h territory, adding another 10 seconds.
It is 63.6 km from Jamaica to Ronkonkoma. An express train from Jamaica to Ronkonkoma stopping only at Hicksville would do the trip in 33 minutes. A limited-stop train that stopped at Floral Park, Mineola, Hicksville, and then all stops to Ronkonkoma would do the trip in 44.5 minutes. A train that made every LIRR stop, even ones that Ronkonkoma trains never stop at today, would do it in 53 minutes. Under the current schedule, limited-stop trains, not stopping at Floral Park (with technical travel time of 43.5 minutes), do the trip in an hour, for a pad factor of 38%. After accounting for the fact that LIRR trains don’t accelerate this quickly because of the derating, we obtain a technical travel time of around 45.5 minutes, for a pad factor of 32%, still immense.
In Zurich, schedules are padded 7%. Rerating the trains to allow faster acceleration, and reducing the pad to 7%, would cut the trip time under the current off-peak stopping pattern from an hour to 47 minutes, which can be taken as either a material speed boost or as an opportunity to make more local stops. As I will argue later, trains should make more local stops – specifically, all from Floral Park east. This is five more stops than trains currently make; taking the 7% pad into account, we get 54 minutes, still a noticeable improvement over the current situation.
It is 17.4 km from Penn Station to Jamaica. Rather than detail the slow zones, I will just give the technical travel time, for a full-acceleration M7 making no intermediate stops: 13 minutes, or 14 with a 7% pad; 1 of those 13 minutes comes from the Penn Station throat and its 25 km/h speed limit, which is one of the reasons I have emphasized the need for simpler interlockings in station reconstruction. The schedule has 19 minutes, which is a 45% pad relative to full-acceleration travel time, and around 40% relative to the derated travel time. This is even worse, which I believe comes from a combination of congestion in the Penn Station area and the timed transfer at Jamaica; these mean that delays on one branch propagate to the others, requiring more slack in the schedule to maintain reliability. However, I will note that Zurich’s 7% pad is in the context of an environment with even more branches sharing a trunk line, and a plethora of timed transfers and overtakes.
It is 44.4 km from Jamaica to Babylon. An all-stop train – counting Saint Albans but not Atlantic Branch-only Rosedale and Valley Stream – would do the trip in 41 minutes. As I’ve argued years ago, the Babylon Branch’s stations all have relatively equal ridership, unlike the Main Line, where a few stations dominate, and therefore, we shouldn’t plan around express trains. The current schedule‘s travel time on all-stop off-peak trains is 53 minutes, a pad of 29% relative to full-acceleration performance and 19% relative to the derated performance. I believe the reason there is much less padding here than on the Ronkonkoma Branch is that the service pattern is simpler: off-peak, all trains make all stops, whereas the Main Line mixes skip-stop and express trains between the Ronkonkoma and Port Jefferson Branches. If all trains make the same stops and there are no overtakes, it’s easier to recover from delays, so there is less need for padding. (A similar principle is that you need less padding on double-track lines than on single-track lines.)
As mentioned before, at Swiss 7% padding, making all Main Line trains all-local from Floral Park east allows 54-minute service from Ronkonkoma to Jamaica. It also allows 69-minute service from Ronkonkoma to Penn Station, with a minute-long dwell at Jamaica. This is two minutes less than the fastest daily train on the current schedule, a nonstop that runs once a day and arrives at Penn Station at 7:30 am, before the greatest rush. Even at the Babylon Branch’s 19% padding, we get 60-minute service from Ronkonkoma to Jamaica and 76-minute service to Penn Station, which compares with 75 minutes for two peak trains with a few intermediate stops, and 82 minutes for off-peak trains with the above-mentioned pattern.
As for the Babylon Branch, going down to 7% padding and rerating the trains at higher speed means all-stop trains, including the three current local stops between Jamaica and Penn Station, would do the trip in 62 minutes. This is competitive with most peak trains: one train stopping only at Jamaica does the trip in 53 minutes, arriving at 7:02 am, but the other morning express trains, with pads varying based on how close to the peak of peak it is, do the trip in 62-65 minutes.
I claim that the solution to the problems of the Main Line is to indeed abolish all express runs. At the peak, there is no excuse for them: current traffic between the Ronkonkoma, Port Jefferson, and Oyster Bay Branches is about 23 trains per hour at the peak, and this means that either all peak-direction trains run local, or trains run one way, with local trains on one track and express trains on the other. The LIRR chooses to sacrifice reverse-peak service, because frankly providing a coherent network is not a priority; the priority is connecting peak-hour suburban travelers to Manhattan, and saving them a few minutes at any cost. This is despite the fact that peak travelers are the most expensive to serve – the peak is what drives capital investment, to say nothing of the crew utilization problems. But in this case, the peak-focused service may be self-defeating, as the above computation of pad ratios shows.
In the morning peak, west of Hicksville, the service pattern should thus be the same for every Ronkonkoma or Port Jefferson Branch train: all stops to Floral Park (where passengers could transfer to the Hempstead Branch), then express to Jamaica and then Penn Station. All trains should be as identical as possible, which means cutting the diesels to shuttles and, in the medium term, electrifying the Port Jefferson Branch to the end, since there is high ridership the entire way, whereas the Oyster Bay Branch and the Main Line beyond Ronkonkoma have low ridership. The dispatching should emphasize headway management rather than the schedule. Since all trains are functionally identical from Hicksville west, it does not matter to passengers if their favorite train left early – the next one will show up in at most 3 minutes. For the same reason, the transfer at Jamaica should not be timed at the peak.
The highest rapid transit capacity in the world is on subway lines that use headway management rather than fixed schedules, including the Moscow Metro and many modern driverless lines, where the limit is 39 tph. I do not expect 39 tph on the LIRR, but there is no demand for that on the Main Line right now; the point is to maintain 24 tph without excessive schedule padding. Off-peak, trains should keep a schedule because the frequency is lower, but the lower frequency is precisely what makes delays not propagate so fast; similarly, off-peak, the Jamaica transfer should be timed. The greatest problem is in the afternoon off-peak, but there, the bulk of boardings are at Penn Station, where delays are less likely since it’s the start of the line.
This pattern also suggests which capital investments the LIRR needs to make: it needs to construct interlockings such that there are no conflicts between Main Line trains and other trains. This means two things. First, grade-separating Queens Interlocking, between the Main Line and the Hempstead Branch, which currently has an at-grade conflict between opposing trains (eastbound Hempstead Branch, westbound Main Line). And second, reconstructing Jamaica’s access tracks from the east in a way that allows the Main Line from the east to continue on the Main Line’s express tracks to the west without interference from other lines. Right now, there’s an at-grade conflict with the Babylon Branch, but only in the same direction, which is less problematic.
This means kicking other branches off the express tracks from Jamaica to Penn Station, the most desirable track pair heading west of Jamaica. This is fine. Passengers on branches that connect to Flatbush, or to the local tracks to Penn Station, could still transfer cross-platform at Jamaica, even if at the peak the connecting train does not wait for them. Besides, as noted above, 7%-padded local trains from Babylon to Penn Station would have the same trip time as all but the single fastest express Babylon Branch train today.
Jamaica’s current track layout is 8 platform tracks, numbered 1-8, north to south. There are platforms between tracks 1-2, 2-3, 4-5, 6-7, and 7-8. This platform configuration allows three-way timed transfers: when a train platforms on track 2, passengers can walk from track 1 to track 3 via the train. Right now, to the west, the Atlantic Branch connects to tracks 3-6, and the four tracks of the Main Line each connects to two Jamaica tracks. But track connections exist to persistently connect tracks 2 and 7 to the express Main Line tracks, making 1 and 8 the local tracks and 3 and 6 the tracks to Flatbush. To the east, the Far Rockaway and Long Beach Branches connect to the Atlantic Branch without conflicting with other trains. Local Main Line tracks connect to tracks 1 and 8 without conflict. The only conflict involves the Babylon Branch, which runs in the middle between the eastbound and westbound Main Line tracks before diverging, and points at tracks 2 and 7. The current service pattern is that most Babylon Branch trains run express from Jamaica to Penn Station, making this track layout desirable. However, if they are switched to the local, single-track flyovers to connect them to tracks 1 and 8 are required, or alternatively a connection to tracks 3 and 6, which can be done without flyovers. In either case, three-way timed transfers would be retained, except at the peak.
Under my through-running proposal, the Atlantic Branch would continue to Lower Manhattan, so its demand would be much greater than today, encouraging a layout in which the Babylon Branch connected to tracks 3 and 6 and went to Brooklyn and Lower Manhattan. The Main Line trains would express to East Side Access and Grand Central, with an additional stop at Sunnyside Junction. The Hempstead Branch, connected to Penn Station and the Empire Connection, would have service increased, with mode-neutral fares encouraging more travel from within New York and Hempstead. I would also propose a new branch of the Hempstead Branch, using the inner Central Branch, going to the East Garden City job cluster. The Oyster Bay Branch would be electrified and its junction with the Main Line grade-separated.
However, I emphasize that none of my proposed schedule changes requires the intensive capital investment associated with connecting Flatbush with Lower Manhattan. Even East Side Access is not required. Queens Interlocking would be grade-separated, and the Oyster Bay Branch would be reduced to a shuttle with an additional track at Mineola (unless electrifying the entire line and grade-separating the junction is cheaper in the short run, which I doubt). Initially, I am not sure the at-grade conflict with the Babylon Branch on the approach to Jamaica would be deadly. The subway has a same-direction at-grade conflict at Rogers Avenue Junction, between the 2, 3, and 5 trains, whose combined peak frequency is higher than that of the Main Line and Babylon Branch’s. Rogers Avenue Junction is a key bottleneck on the numbered lines in New York, which is why the LIRR should not replicate it in the long run, but in the short run, it is fine.
To conclude, here are proposed westbound timetables for Ronkonkoma, Babylon, and Hempstead trains. These assume no new stations and only the minimally required physical infrastructure (that is, grade-separating Queens Interlocking).
|New Hyde Park||7:44|
|New York Penn||8:08|
This is a total travel time of 68 minutes, and not 69 as advertised above. This is because of rounding artifacts.
|Country Life Press||7:33|
|New York Penn||8:12|
The 4-minute difference between local and express travel time between Jamaica and Penn Station comes from the fact that the intermediate stations are for the most part in slower zones than 130 – only at Forest Hills is there enough of a distance to get up to 130, and only west of the station, not east. Erratum: although it is true the stations are in slow zones, I wrote this paragraph thinking there are four intermediate stations, where of course there are only three; 4/3 = 80 seconds per stop, which comes from rounding artifacts.
The Hempstead Branch has a 1.5-km single-track segment starting west of Hempstead and ending east of Garden City. It is quite slow; the 25 km/h curve just north (west) of Country Life Press has geometry good enough for 50 km/h without any superelevation (cant deficiency would be 150 mm), and with 150 mm superelevation would be good for 70. Replacing that entire 25-50 km/h segment with 70 km/h saves about a minute of travel time.
|New York Penn||8:07|
I arbitrarily chose the Ronkonkoma departure time to be 7:00, and then chose the Hempstead Branch schedule to allow a timed transfer at Jamaica. The five-minute offset for the Babylon Branch should be suggestive of the proposed frequency: off-peak, every ten minutes on the Babylon Branch (possibly every twenty but also every twenty on the West Hempstead Branch), every ten minutes on the Hempstead Branch (possibly every twenty but also every twenty on the Central Branch to East Garden City), and every ten minutes on the Main Line, with each of the Ronkonkoma and Port Jefferson Branches getting a train every twenty minutes. The Atlantic Branch trains should run every twenty minutes per branch, with a three-way timed transfer with the Main Line and Hempstead Branch. Off-peak, the Babylon Branch doesn’t transfer to anything else, so there is no need to worry about its at-grade conflict at Jamaica.
Update 9/24: as Alex Block notes in comments, sources at Amtrak deny the story, saying that Schumer spoke too soon, and there are still two bidders and Amtrak has not yet made its choice. If the cost turns out to be $1-1.25 billion rather than $2.5 billion, I will withdraw any and all criticism of the procurement process.
A press release from Senator Charles Schumer’s office is abuzz: Amtrak chose Alstom’s bid for its next order of high-speed trainsets, the Next-Generation Acelas. The press release mentions the size of the contract, $2.5 billion, and the number of jobs it would create, 750; it did not include any information relevant to passengers, such as the number of trains, the expected schedule of delivery, the expected frequency, and the expected travel time. Various media outlets have reprinted Schumer’s press release without such additional information, or indeed any analysis. Let me rectify this and provide some background as to why this order is a fleece.
The order is for 28 trainsets with 425 seats each. This can be seen here and here. Of those 28 sets, 25 should be available for maximum service, well below the 98% peak availability achieved by the TGV, but an improvement over the Acela’s current 16 trains available out of 20. There is no mention of the number of cars, which is how orders are usually priced. However, on page 30 of the technical specs, it is mentioned that the maximum length is 200 meters, equivalent to 8 cars. The capacity is equivalent to about six cars’ worth of seating at the normal seat density of economy-class HSR (including the Amtrak Regional coach), or about seven cars’ worth averaged over all occupied Acela cars. The RFP mentions half a bistro car with an option for a full car (page 21 of instructions to offerors), so eight cars per train is a reasonable assumption. I have seen references to ten cars per set, which I believe come from the option for two additional cars per train (the instructions phrase this as “an extra 33.33% capacity”). From Schumer’s press release it’s difficult to know whether the $2.5 billion figure is the base order or also the option.
Eight cars per train times 28 trains equals 224 cars. $2.5 billion divided by 224 equals $11.2 million per car; if I am wrong and these are ten-car trains, then it is $8.9 million per car. In China, a very high-speed train, capable of 350-380 km/h, costs $4 million per car; this is $900 million at the size of Amtrak’s order. In Europe, the new Eurostar order cost a total of €600-700 million for ten 16-car Velaro trainsets, about $4.7-5.5 million per car in PPP terms (see here and here); the uncertainty comes from euro:pound conversion rates and from the fact that a portion of the order is for refurbishment of the older trainsets. Siemens also sold 8-car Velaros to Deutsche Bahn for $5.2 million per car, again in PPP terms. Japanese trains are even cheaper, about $3 million per car in a recent N700 order, but only last 20 years, whereas European HSR trainsets last 40 and Amtrak specified a 30-year shelf life. The only non-US trainset order that I’ve seen that approaches the $10 million per car mark is the Velaro RUS, which is €600 million for eight 10-car trains, and this includes substantial modifications, such as winterization.
There is no excuse for such high costs. The technical specs are not particularly innovative: on page 22 of the document linked above, it is mentioned that cant deficiency should be 127 mm if the trains don’t tilt and 229 if they do, both of which figures are unimpressive by the respective standards of non-tilting and tilting trains. There is no explicit requirement for tilt. There is a requirement that trains be capable of traveling between New York and Washington in 2:21 (current trip time is 2:48) and between New Haven and Boston in 1:51 (current trip time is about 2 hours, skipping New London, which the specs require trains to stop at); there is no mention of which track upgrades are forthcoming, but given Amtrak’s heavy schedule padding, it is not difficult for a good train to meet the requirements. I do not bring these specs up to attack Amtrak for not demanding more of the trains, but to note that what Amtrak is asking is standard, so there is no reason for trains to be unusually expensive.
I will note that due to Buy America provisions, the trains will be manufactured in the US, at Alstom’s factory in Hornell. This has not caused cost blowouts for the large orders made by the New York subway, the LIRR, and Metro-North, but perhaps this order is small enough that requiring Alstom to build it at a new factory leads to major cost increases. It is also possible that due to difficulties in the bidding process, there are fewer bidders than is normal – Bombardier dropped out of the process last year, and in general, some US contracts have just one bid, with correspondingly elevated prices. But regardless of the reason, Amtrak’s order comes at a factor-of-two cost premium, and Schumer just expressed pride at the few hundred jobs that this waste would create.
Twenty-five billion dollars. The New York region’s political heavyweights – Andrew Cuomo, Chris Christie, Chuck Schumer, Cory Booker, Bill de Blasio – all want new Hudson tunnels, without any state funding for them; Schumer is proposing federal funding and a new interstate agency, parallel to the existing Port Authority, and a total budget of $25 billion. This is the highest figure I have seen so far; Amtrak still says $16 billion and Cuomo says $14 billion, and it’s likely the Gateway tunnels are indeed about $16 billion, while the remainder is for associated projects, such as fully four-tracking the line from Newark to the tunnel portal, a distance of about 11 kilometers. It is not my intention to criticize the cost; I’ve done that before.
Instead, I would like to point out that each time Gateway is the news, there usually seems to be a fresh cost escalation. Is it a $10 billion project? A $14 billion project? A $16 billion project? Or a $25 billion project? And what is included exactly? Amtrak does not make it clear what the various items are and how much they cost; I have not seen a single cost estimate that attempts to establish a baseline for new Hudson tunnels without the Penn Station South component, which would provide a moderate short-term boost to capacity but is not necessary for the project. The articles I’ve seen do not explain the origin of the $25 billion figure, either; it may include the tunnel and full four-tracking of Newark-New York, or it may include additional scope, for example Amtrak’s planned vertical circulation for a future (unnecessary) deep cavern for high-speed rail (see picture here).
The main issue here, the way I see it, is the interaction between public trust and political self-aggrandizement. It is common in all aspects of Israeli governance for new ministers to announce sweeping changes and reorganizations, just to remind the country that they exist and are doing something; this generally makes it harder to implement gradual reforms, and makes it completely impossible to do anything by consensus. Implementing a plan that was developed by consensus over many years makes one a bureaucrat; leaders change everything. In the US, this is the case not everywhere in government, but at least within public transportation infrastructure.
As we see in the case of Schumer’s call for a new interstate authority, the changes a heavyweight politician makes in order to appear as a leader have nothing to do with real problems that the project may have. Solving those problems requires detailed knowledge of the project at hand, which is the domain of bureaucrats and technocrats, and not of heavyweight politicians. Even a heavyweight who understands that there is a problem may not know or care about how to fix it: for example, Christie used the expression “tunnel to Macy’s basement,” invoking the deep cavern, to explain why ARC was wasteful, but chose to cancel the project rather than to remove the cavern and restore a track connection from the tunnel to Penn Station, which was in the official ARC Alt P plan until it was cut to limit the cost overruns. Managing a project is hard, and is, again, the domain of technocrats. The heavyweight will grandstand instead, regardless of whether it means canceling the project, or proposing an entirely new layer of government to build it.
As for trust, let us look at the benefits of new Hudson tunnels. The traditional, and least objectionable, is added capacity: the existing tunnels are currently at capacity during rush hour, and there’s much more demand for rail travel from New Jersey to Manhattan than they can accommodate. We can measure this benefit in terms of the combination of increased ridership from more service from more suburban areas, reduced crowding, and possibly slightly higher speeds. As a crude estimate of this benefit, current New Jersey Transit ridership at Penn Station is 87,000 per weekday in each direction. Doubling capacity means roughly doubling ridership, which would come from a combination of induced demand and diversion of traffic from cars, Port Authority buses, and commuter rail-PATH connections. This means the new tunnel can expect about 175,000 new commuter rail trips per weekday. At $10,000 per weekday trip, which is about average for very large non-US cities’ subway extensions, this justifies $1.75 billion. At $20,000, about the same as the projection for Grand Paris Express, Crossrail, and Second Avenue Subway Phase 1, all of which are justified on grounds of ridership and capacity on parallel lines, this is $3.5 billion. At $40,000, about the same as old projections for Second Avenue Subway Phase 2, which I used to analyze de Blasio’s Utica subway proposal, this is $7 billion. A $25 billion budget corresponds to a cost per rider well into the range of airport connectors.
Now, I’d like to think that informed citizens can look at these costs and benefits. At least, the fact that public transit projects only cost as much per rider as Gateway if they’re airport connectors (thus, of especial interest to the elites) or if something very wrong happened with the ridership projections, suggests that there is, normally, a ceiling to what the political system will fund. Even at $14-16 billion, the two states involved and the federal government groaned at funding Gateway, speaking to the fact that it’s not, in fact, worth this much money. In contrast, a bigger project, with bigger benefits, would be funded enthusiastically if it cost this much – for example, California already has almost this much money for high-speed rail, counting Prop 1A funds that are yet inaccessible due to the requirement of a 50/50 match from other sources.
Against this background, we see scare stories that Gateway must be built for reasons other than capacity and ridership. The old tunnels are falling apart, and Amtrak would like to shut them down one track at the time for long-term repairs. The more mundane reality is that the tunnels have higher maintenance costs than Amtrak would like since each track can only be shut down for short periods, on weekends and at night. This is buried in technical documents that don’t give the full picture, and don’t give differential costs for continuing the present regime of weekend single-tracking versus the recommended long-term closures. The given cost for Sandy-related North River Tunnel repairs is $350 million, assuming long-term closures, and it’s unlikely the present regime is billions of dollars more expensive.
I am reminded of the Tappan Zee Bridge replacement: the existing bridge has high maintenance costs due to its age and poor state, but the net present value of the maintenance cost is $2.5 billion and that of the excess maintenance cost is less, both figures well below the replacement cost. The bridge itself is structurally sound, but in popular media it is portrayed as structurally deficient. This relates to the problem of heavyweight politicians, for the Tappan Zee Bridge replacement is Cuomo’s pet project.
More fundamentally, who can trust any claim Amtrak makes about the structural soundness of tunnels? It says a lot that, when I asked on Twitter why transportation authorities do not immediately shut down unsafe pieces of infrastructure, various commenters answered “politics,” and on one (I believe James Sinclair) suggested that Amtrak order an emergency closure of one of the Hudson tunnel tracks just to drive home the point that new tunnels are necessary. I would like to stress that this is not Amtrak or a heavyweight proposing that, but the mere fact that commenters can seriously talk about it is telling. Most of the writers and commenters on the US transit blogosphere are very progressive and hate the Republicans; I have not seen a single comment recommending that the Democrats steal elections, fudge official statistics to make the party look more successful, or arrest Republican politicians on trumped-up charges, because in the US (and other first-world democracies), this is simply not done, and everyone except conspiracy theorists recognizes it. But politicizing the process of deciding which infrastructure projects are necessary for safety purposes and which are simply service expansions is normal enough that people can propose it half-seriously.
This brings me back to the issue of what I want the politicians to do, and what I expect them to do. What I want them to do is to be honest about costs and benefits, mediate between opposing interests (including different agencies that fight turf battles), and make decisions based on the best available information. This would necessarily limit costs, since, from the point of view of a member of Congress, if they get $25 billion for a piece of infrastructure then they cannot get $25 billion for another priority of theirs. They don’t do that, not in the US, and I’ve learned not to expect any better, as have the voters. Instead of working to make $25 billion go a longer way (to put things in perspective, I expect my regional rail tunnel proposal to cost $15-20 billion, at Crossrail 2 costs), Schumer is working to make $25 billion to sound like it’s going to a bigger deal than the new Hudson tunnels actually are.
None of this is a secret. American voters have learned to expect some kind of machine-greasing and politicking, to the point of losing the ability to trust either the politicians or the agencies, even in those cases when they are right. The result is that it’s possible to stretch the truth about how necessary a piece of infrastructure is, since people would believe or disbelieve it based on prior political beliefs anyway, and there is no expectation that the politicians or public authorities making those claims will have to justify them to the public in any detail. Lying to the public becomes trivially easy in this circumstance, and thus, costs can rise indefinitely, since everyone involved can pretend the benefits will rise to match them.
In North America, commuter trains run with conductors, often several per train. On most systems they walk the entire length of the train to check every passenger’s ticket, whereas on a few, namely in California, they do not do that anymore, but there are nonetheless multiple conductors per train. In addition, the scheduling is quite inefficient, in that train drivers do not work many revenue hours. I investigated what effect this has on operating costs, and it turns out that the effect on the marginal operating costs, which are important for off-peak service, is large: on the LIRR and Metro-North, nearly fivefold improvements in revenue train-hours per on-board employee (driver or conductor) are possible, which would halve the marginal operating cost per train-km. The bulk of this post is dedicated to explaining the following breakdown of variable operating costs:
The National Transit Database has figures for service in car-km and car-hours for a variety of US transit agencies. In New York State, the Empire Center has lists of every public employee’s position and pay, which we can use to figure out the average pay of a train driver and conductor and the productivity of their labor. The NTD numbers are as of 2011, so I will use the number of employees of 2011, but the pay per employee of 2014 (at any rate, there have been no major service changes since 2011, so numbers are similar). In 2011, the LIRR averaged 5,000 car-hours per driver-year, and Metro-North averaged 4,000; the LIRR runs longer trains than Metro-North, so the figure for both railroads appear to be about 500 train-hours per driver-year. Both railroads had a little bit more than 2 conductors per driver on average (2.14 Metro-North, 2.47 LIRR). The average pay of a driver, as of 2014, is $109,000 on the LIRR and $120,000 on Metro-North, whereas the average pay of a conductor is $112,000 on the LIRR and $96,000 on Metro-North.
From this, we can piece together the average operating cost of commuter rail derived from on-board labor, per train-hour: $771 on the LIRR, $714 on Metro-North. Assuming 8 cars per train (and again, the LIRR tends to run longer trains), this is around $90-95 per car-hour. According to the NTD, the average operating cost of both was about $550 per car-hour in 2011, but this includes fixed costs, such as management and rolling stock. As we will see, variable operating costs are much lower.
As a digression, I’d like to point out that the peaky schedule of commuter rail contributes to the low productivity of the drivers. Crew schedules include substantial gap time between trips, and occasionally, especially on low-frequency diesel branches, they deadhead. That said, the subway’s number of revenue train-hours per driver is not materially different. For higher figures, one must leave New York. Toei got about 700 revenue hours per driver when I last checked, but I can no longer find the reference. On the London Underground, I do have fresh references, pointing in the same range: 76.2 million train-km per year at 33 km/h average speed (from TfL’s facts and figures), and a bit more than 3,000 train operators. In 2012, the last year for which there’s actual rather than predicted data (see also PDF-p. 7 of the TfL Annual Report), there were 720 revenue hours per train driver. This is in tandem with a less peaky schedule than in New York: although the average speed is barely higher than that of the New York subway, as reported in the NTD, the trains travel about 180,000 km per year (see fact 149 here), twice as long as in New York. In Helsinki, metro trains run every 10 minutes all day on each branch, every day, without any extra peak service, contributing to even higher utilization: the schedules show 65,000 revenue-hours per year, whereas a factsheet from 2010 shows 75 metro drivers, for a total of 867 revenue hours per driver. In both the UK and Finland, average hours per employee are marginally shorter than in the US; London Underground drivers have 36-hour workweeks.
The importance of this computation is not just to highlight that 44-73% improvement in revenue-hours per employee is possible, but to point out that, on the margins, adding off-peak service would make crew schedules more efficient, since higher frequency would reduce the need to deadhead and to wait between trains. This means that, although the average operating cost may be about $750 per train-hour, the marginal cost is lower, even without changes to work rules.
Suppose now that trains run without conductors, using proof-of-payment as on light rail lines, even ones in North America, and on countless commuter rail systems in Continental Europe. Suppose also that there are 720 revenue-hours per driver, and that a driver is paid $115,000 per year. This means that running extra trains would not cost $90-95 in on-board labor per car-hour, but only $20, a nearly fivefold improvement. At Helsinki’s level of productivity, a nearly sixfold improvement to $16.60 is possible. At the LIRR’s present average speed of 50 km/h (compared with 53 on New Jersey Transit and 59 on Metro-North), the fivefold improvement based on London Underground productivity would cut the average cost per car-km from $1.80-1.90 to $0.40; at a higher but still realistic 67 km/h, it’s a cut from $1.35 to $0.30. A large majority of this cut comes from eliminating conductors, which, by itself, would cut costs threefold, but raising driver productivity would allow an additional cut of 30-40%. I again stress that the marginal cost is lower than the average cost computed here, since less peaky schedules come with simpler crew scheduling; more off-peak service would by itself cut the average cost, which means its marginal cost would be quite low.
Let us now look at other variable costs than on-board labor. Two years ago, I did this computation for high-speed rail, and found that, provided the schedules did not have extra rush hour service, operating expenses would be very low. We can do the same computation for commuter rail, and note that the lower speeds imply that operating and maintenance costs are spread across less passenger-km, raising costs. Let us consider train maintenance, cleaning, and energy.
I do not have information about train maintenance costs on commuter rail. Instead, I will use those of high-speed rail, for which standards are higher. As I noted in my computation from two years ago, the reference here is California HSR’s 2012 Business Plan, which aggregates these figures from around the world on PDF-p. 136. Maintenance costs per train-km are $4.47 for the Tokaido Shinkansen (with 16-car trains) and $2.58 per the UIC (with what I assume are 8-car trains), both in 2009 dollars. These figures cluster around $0.30 per car-km in 2009 dollars, or $0.30-35 per car-km in 2014 dollars.
With cleaning, there is some information about commuter rail: the Empire Center has lists of coach cleaners on Metro-North (there are 314) and their pay (on average, a little less than $50,000 a year). This seems high given the amount of service Metro-North runs – about $0.15 per car-km. Shinkansen trains are cleaned on a seven-minute turnaround in Tokyo, using one cleaner per standard-class car; this includes tasks that are not required on commuter rail, such as flipping seats to face forward. A cleaner making $30 per hour cleaning a single car per 15 minutes, with each train cleaned once per 150 km roundtrip, would cost $0.05 per car-km. I suspect that part of the low productivity of Metro-North cleaners is again a matter of low off-peak frequency – Shinkansen cleaners work almost continuously – but I don’t have comparative data to back this up; New York City Transit pays even more per cleaner per car- or bus-km, but this is on much lower average speed, and per car- or bus-hour, it pays about $6.40, vs. about $8.90 for Metro-North. I’m going to pencil in $0.10 per car-km as the cost of cleaning.
Energy costs we can compute from first principles. This is easier than for HSR, since commuter trains travel at such speed that a large majority of their energy consumption is in acceleration, rather than cruising. The explicit assumptions I am making is that the top speed is 130 km/h (the two main LIRR lines are mostly 80 mph territory), each car weighs 54 metric tons (the LIRR M7s weigh 57.5 and the Metro-North M8s even more, but this is very high by international EMU standards, thanks to FRA regulations), the average distance between stations is 4 km (the LIRR’s average is less than that if all trains make all stops and more if there are some express trains), and the track resistance per unit of train mass is the same as for the X 2000, for which data exists on PDF-p. 64 of a thesis on tilting trains. Regenerative braking is assumed to exactly cancel out with losses in transmission. Train acceleration performance is assumed to be like that of the FLIRT, which would take about a kilometer to accelerate to line speed and have about 2 km of cruising before slowing down for the stop; the M7 has inferior performance, but this would reduce energy consumption since trains would spend more time at lower speed.
With the above assumptions, each acceleration, cruise, and deceleration cycle between stations consumes about 13 kWh, of which 10 kWh is required to accelerate the train to top speed, and the other 3 are for overcoming track resistance. See rough computations in a subthread on California HSR Blog starting with this comment, and bear in mind the initial comment made a large computational error. As for April of this year, transportation electricity costs in the state are $0.1245 per kWh, giving us about $1.60 per 4-km interstation, or $0.40 per car-km.
Overall, those three items are $0.80 per car-km. This means that going from paying train crew $1.35 per car-km to paying them $0.30 per car-km represents halving of direct marginal operating expenses: it means going from $2.15 to $1.10 per car-km. Finally, let us add management costs, which are not exactly marginal costs, but do grow as the workforce grows, since more employees require supervisors. At RENFE, we can extract 0.27 support and management employees per operations employee from the data on PDF-p. 46 of its 2010 executive summary. On the Helsinki urban rail network, the corresponding figure is 0.34 as per the factsheet referenced above. This affects train crew, cleaning, and maintenance staff, but not energy. If this means 30% extra costs, this means going from $2.675 to $1.31 per car-km – again, we see costs are halved.
The off-peak LIRR fare is 15 cents per kilometer at long distances (14 to Ronkonkoma, but much more at shorter distances, for example 21 to Hicksville). If the marginal cost of running off-peak service is $1.31 per car-km, it means a car needs to have 9 passengers without season passes on it paying 15 cents per km for the trip to break even. If it’s $2.675, it needs 18. Passengers who commute off-peak and get season passes for those commutes also contribute, but less – a monthly pass for Ronkonkoma is $377, which at 46 trips a month is 10 cents per kilometer. It is not hard to have 9 passengers even on a long train, or even 13 (at the lower rate of season passes); Ronkonkoma itself is a park-and-ride, where this is less likely, but high enough passenger volumes as far as Mineola and Hicksville and all over the Babylon Branch are quite likely. If the required minimum is 18, let alone 26, this is substantially harder.
I harp on North American mainline rail operations for a variety of antiquated practices, but the on-board overstaffing is by far the worst. While improvement in train driver productivity can occur as a natural byproduct of improvement in off-peak frequency, getting rid of conductors is not so easy. It means a fight with the unions over job losses. Some of the required layoffs can be mitigated by retraining conductors as train drivers and running more service, but this would not boost service hours by a factor of 5; on the Ronkonkoma Branch, the peakiest of the three long LIRR lines, boosting off- and reverse-peak frequency to half the peak frequency would only increase train service by a factor of about 1.8.
I am not an expert on labor relations, so I do not know if any solution barring a prolonged SEPTA-style strike could work, alone or in combination. One possibility would be to commit to reducing working hours in the next five or ten years instead of hiking pay; working hours would be gradually reduced to core Western European levels, with 35-hour workweeks and 6 weeks of paid vacation, and hourly pay would rise as scheduled while annual pay would be frozen. Another possibility is that the MTA would help laid off employees find private-sector work, as happened in the 1980s with Japan National Railways (see PDF-pp. 103-4 of a handbook on rail privatization). This possibility requires implementing the reform at a time of wage growth and low unemployment, when private-sector work is easier to find, but the US is posting strong job growth numbers nowadays and is projected to keep doing so for at least another year.
But whatever happens, the most important reform from the point of view of reducing marginal off-peak service provision costs is letting go of redundant train crew. Halving the variable operating costs is exactly what is required to convert the nearly empty off-peak trains from financial drains to an extra source of revenues, balancing low ridership with even lower expenses. This would of course compound with other operating efficiencies, limiting the losses of branch lines and turning the busier main line trains into profit centers. But nowhere else is there the possibility of cutting costs so much with one single policy change as with removing conductors and changing the fare enforcement system to proof-of-payment.
Update 7/31: first, check comments below about maintenance costs: as far as I can tell from poorly presented Empire Center data, they are about 2.5 times higher, for both trains and the infrastructure, than the maintenance costs of high-speed rail. Although the effect of reducing those costs to conventional HSR level is larger than the effect of eliminating conductors, the details of reducing maintenance costs are far more delicate than those of eliminating conductors and running trains more often so that train drivers have less downtime.
Second, there is a small error in the above calculations: the figure of $90-95 in crew salary per car-hour is based on two conflicting assumptions. To get to $771 per train-hour on the LIRR, I assumed the LIRR ran 10-car trains. To get down to the $90-95 range, I assumed 8-car trains; 10-car trains would make this $77/hour. If we redo the entire calculation with 10-car trains, still with HSR maintenance costs, then instead of a cut from $2.675/car-km to $1.31/car-km, improved labor efficiency would cut costs from $2.415/car-km to $1.21/car-km. This is based on exact LIRR salaries, whereas the original calculation assumes hybrid LIRR/Metro-North salaries, and Metro-North pays drivers better than the LIRR.
Now, trains are somewhat longer at the peak than off-peak. If off-peak service is already with 8-car trains, and the average number of conductors is constant, then the original calculation (a cut from $2.675 to $1.31) still holds. After all, the salaries of train drivers and conductors are the same no matter how long the train is. But the number of conductors is not constant – let’s say it is proportional to train length, so 8-car LIRR trains have 2 conductors instead of 2.47, just as Metro-North’s average number of conductors per train is shorter than the LIRR’s, in tandem with its shorter consists. This changes the calculation to a cut from $2.535 (reflecting fewer conductors than in the original calculation) to $1.31. Observe that no matter what assumption we use, the operating cost cut coming from removing conductors and using drivers more efficiently is about 50%, give or take 1-2%.
There’s an article in the New York Times by its architecture critic Michael Kimmelman, making a forceful case for the Gateway Project’s necessity. Like nearly all transit activists in New York, I think new Hudson tunnels are the top infrastructure priority for regional rail; like nearly all transit activists, I groan at Amtrak’s proposed budget, now up to $16 billion (but unlike most, I think that it should not be built unless costs can be brought down – I’d peg their worth at $5 billion normally, or somewhat more in a crunch). I would like to explain one specific piece of scope in Amtrak’s plan that can be eliminated, and that in fact provides very little transportation value: Penn Station South.
Like all proposals for new Hudson tunnels, Gateway is not just a simple two-track tunnel between New Jersey and Penn Station. No: the feuding users of Penn Station all think it needs more tracks. The rejected ARC proposal had a six-track multilevel cavern, and Gateway has Penn Station South, a proposal to demolish an entire block south of Penn Station and build seven additional platform tracks. The cost of just the real estate acquisition for Penn South: $769 million to $1.3 billion, at today’s prices. Trains using the preexisting tunnels would have to go to the preexisting Penn Station tracks, which I will call Penn Classic; trains using the new tunnels could go to either Penn Classic or Penn South, but the junction is planned to be flat. For illustration, see PDF-p. 12 of a press release of the late Senator Lautenberg, and a clearer unofficial picture on Railroad.net.
As a result of this proposed track arrangement, train services would initially suffer from the capacity limitations of flat junctions. Like Penn Station’s tracks 1-4, Penn South would be terminal tracks. This means that the only service possibilities are as follows:
1. Schedule all through-trains, such as Amtrak trains, through the preexisting tunnels.
2. Do not schedule any westbound trains from Penn South or any eastbound trains entering the preexisting Penn Station tracks: for example, no westbound trains from Penn South in the morning peak, and no eastbound trains entering Penn Classic in the afternoon peak.
3. Schedule around at-grade conflicts between opposing traffic.
Option #2 is impossible: Penn South has 7 tracks. If trains can enter but not leave in the morning, there will be room for 7 trains entering in the morning, a far cry from the several dozens expected. Option #1 is the better remaining option, but is ruled out, since Amtrak wants to use the new tunnels for its own trains. This leaves option #3, which restricts capacity, and complicates operations. Thanks to Amtrak’s imperialism, taking over regional rail projects for its own ends, Penn South has negative transportation value relative to just building new tunnels to Penn Classic’s tracks 1-4 (the transportation value relative to doing nothing is of course positive).
I emphasize that the negative transportation value of Penn South comes entirely from Amtrak’s involvement. The same infrastructure, used by passenger rail agencies that were more interested in providing high-quality public transportation than in turf wars, would have positive transportation value. However, as I explained to Kimmelman, this positive transportation value is low, and does not justify even the cost of real estate acquisition, let alone that of digging the station.
Briefly, as can be seen in the diagrams, the interlocking between the two new tunnel tracks and Penn’s eleven terminal tracks – tracks 1-4 of Penn Classic, and all of Penn South – is exceedingly complicated, which would limit approach speed, and not provide much flexibility relative to the number of tracks provided. This is to a large extent unavoidable when two approach tracks become eleven station tracks, but it does lead to diminishing returns from extra tracks. This is one of the reasons it’s easier if trains branch: it’s easier to turn 12 trains per hour on two tracks than to turn 24 on four (although both are done in Tokyo – indeed, the Chuo Line still turns 27 tph on two tracks).
Avoiding large crunches like this at urban terminals a benefit of through-running. This is hard to realize initially unless the new tunnel is what I call ARC-North. It’s still possible to through-run trains, pairing the new tunnels with the southern pair of East River Tunnels and the old tunnels with the northern pair, but it requires a lot of diverging moves at interlockings, limiting speed. Penn Station plans should be built with a long-term goal of simple moves at interlockings, to (slightly) increase speed and capacity and reduce maintenance needs.
However, it’s still possible to square the circle by requiring trains to turn fast on tracks 1-5 of Penn Station (track 5 splits to a terminating end and an end that runs through east of New York). Tokyo would be able to turn a full complement of 24 trains per hour on these tracks. Most other cities would not. However, as somewhat of a limiting European case, the RER A turns a peak train every 10 minutes on single track at Le Vésinet-Le Pecq, the next-to-last station on the Saint-Germain-en-Laye branch; Le Pecq has two through-tracks (also hosting a train every 10 minutes) and one terminal track. See map and schedule. This does not scale to 24 tph on four tracks; somewhat tellingly, those trains do not continue to the terminus, which is a three-track station, implying turning 12 tph on three tracks is problematic. The RER E turns 16 tph at the peak at Haussmann-Saint Lazare, a four-track city terminus, pending under-construction extension of the line to the west, which would make it a through-station.
If we accept 16 tph as the capacity of new Hudson tunnels without new Penn Station tracks, then the question should be what the most cost-effective way to raise future capacity is. An extra 9 tph, the equivalent of the difference between 16 tph and the 25 tph that the current tunnel runs and that Amtrak projects for Gateway, is within the capabilities of signaling improvements and better schedule discipline. Again looking to Paris for limiting cases, the combined RER B+D tunnel between Gare du Nord and Châtelet-Les Halles runs 32 tph, without any stations in the tunnel (the RER B and D use separate platforms), while the moving block signaling-equipped RER A runs 30 tph on its central segment, with stations (as do the S-Bahn systems of Berlin and Munich). The RER E was planned around a capacity of 18 tph, but only 16 tph are run today. 18+32 = 50 = 25+25. France is not Japan, with its famous punctuality: French trains are routinely late, and as far as I remember, the RER B has on-time performance of about 90% based on a 5-minute standard, worse than that of Metro-North in its better months.
More importantly, dropping Penn South from the Gateway plan saves so much money that it could all go to through-running, via a new tunnel from tracks 1-5 to Grand Central. This is about 2 km of tunnel, without any stations; in a normal city this would cost $500 million, the difficulty of building in Midtown canceling out with the lack of stations, and even at New York construction costs, keeping the tab to $2 billion should be doable. The 7 extension is $2.1 billion, but includes a station; an additional proposed infill station at 10th Avenue, dropped from the plan, would’ve $450 million, giving us $1.6 billion for about 1.6 revenue route-km, rising to 2.3 km including tail tracks – less than a billion dollars per kilometer.
At $2 billion, the premium over $1 billion of impossible-to-cut real estate acquisition costs is down to $1 billion. It’s unlikely the construction cost of Penn South could be just $1 billion, without general reductions in city construction costs, which would enable the Penn-Grand Central link to be cheaper as well. Each Second Avenue Subway station is about a billion dollars, and those stations, while somewhat deeper than Penn Station, are both much shorter and narrower than a full city block. The result is that building a Penn-Grand Central link is bound to be cheaper than building Penn South, while also providing equivalent capacity and service to a wider variety of destinations via through-running.
One difficulty is staging the tunnel-boring machines for such a connection: building a launch box involves large fixed costs, especially in such a crowded place as Midtown. One of the reasons Second Avenue Subway and the 7 extension are the world’s most expensive subway project per kilometer is that they’re so short, so those fixed costs are spread across less route length. The best way to mitigate this problem is to build the link simultaneously with the new Hudson tunnels. The staging would be done on Penn’s tracks 1-4, whose platforms would be temporarily stripped; the construction disruption involved in the tunnels is likely to require shutting those tracks down anyway. Depending on the geology, it may even be possible to use the same tunnel-boring machine from New Jersey all the way to Grand Central.
This doesn’t save as much money – the Penn-Grand Central link is extra scope, with its own costs and risks. However, unlike Penn South, it is useful to train riders. Penn South allows terminating trains at Penn Station more comfortably, without having to hit the limit of large-city terminal capacity; the Penn-Grand Central link creates this capacity, but also lets riders from New Jersey go to Grand Central and points north (such as Harlem, but also such more distant commercial centers as Stamford), and riders from Metro-North territory go to Penn Station and points west (such as Downtown Newark).
Normally, I advocate unbundling infrastructure projects, because of the tendency to lump too many things together into a single signature plan, which then turns into political football, a sure recipe for cost overruns. However, when projects logically lead to one another, then bundling is the correct choice. For example, building an entire subway line, with a single tunnel-boring machine and a single launchbox, usually costs less than building it in small stages, as is the case with Second Avenue Subway. New Hudson tunnels naturally lead into a new tunnel east of Penn Station, regardless of where this tunnel goes; and once a tunnel is built, its natural terminus is Grand Central.
The night before last, a Northeast Corridor Amtrak train derailed in Philadelphia, killing seven people. For some overviews of what happened, see Vox and Huffington Post. I am not going to talk directly about the accident here; it appears to be the same kind of derailment as on Metro-North a year and a half ago. Instead, I’m going to talk about the general issue of redundancy, which I saw people bring up in response to the train shutdowns that followed the crash. This is not the first time I hear about this; redundancy figures prominently into the list of benefits touted for new rail tunnels across the Hudson, allowing Amtrak to shut down the existing tunnels for repairs. Even before Amtrak proposed the Gateway project, transit activists talked about redundancy as a positive feature, for example Cap’n Transit. In this post, I am going to explain why, in public transportation and intercity rail, redundancy is in fact far less useful than other investments for the same amount of money.
First, let us list the various high-caliber rail networks of the world. In high-speed rail, the biggest networks are those of China, Japan, and France. None of them has redundancy, in the sense that there is more than one way to get between two cities on high-speed track. JR Central is building a second line from Tokyo to Osaka, but this is because the existing line is at capacity, running about 14 trains per hour into Tokyo at the peak; redundancy is a minor consideration. In regional rail, the busiest networks do have some redundancy, in the sense that if one line is shut down then people can take a parallel line, but this is because these networks are so busy that in most directions there’s enough demand to fill multiple lines. In Tokyo, which has the largest regional rail network, the parallel line is usually run by a competing company, so within each company’s network there’s little redundancy.
The reason for this non-redundant operation is simple: building new rail lines is expensive, while maintaining them adequately so that they don’t break down is cheap. Amtrak thinks that the Gateway tunnel will cost $16 billion. The program to repair the damage the preexisting tunnels suffered in Hurricane Sandy is $700 million, which assumes an accelerated construction schedule in which the tunnels will be shut down one track at a time, but conversely also includes work in the worse-damaged East River tunnels and not just the tunnels across the Hudson. This is a one-time repair after salt water intrusion, not annual ongoing maintenance. New Hudson tunnels are a necessary project for capacity reasons, but whatever benefit they have for redundancy is a fraction of their cost.
For high-speed rail, too, the cost of maintenance are far smaller than those of construction. The average maintenance costs of a single route-km of HSR are about €100,000 per year, versus €20 million for construction (see PDF-p. 9 of a study by Ginés de Rus about HSR between Stockholm and Gothenburg). With this amount of maintenance, there need not be any closures or disruptions in service.
Consider the Northeast Corridor, more concretely. To guarantee redundancy everywhere, so that train accidents do not disrupt the line, is to restore some passenger service along the former Baltimore and Ohio and tie-ins. Between Philadelphia and New York this means the West Trenton Line; between Philadelphia and Washington this means the CSX freight line. This also requires new Hudson tunnels. The cost of each of these elements is in the billions, and for the most part, with the exception of the new Hudson tunnels the transportation benefit is very low, especially south of Philadelphia, where there aren’t enough people to justify a second commuter line. Between New York and New Haven, there are no good alignments for a second route except for short bypasses; that’s what makes constructing HSR there so difficult.
Redundancy is a good feature of networks where failures are frequent and unavoidable; for such systems, redundancy is useful, as is the concept of failing gracefully. Rail transit is not such a network. It is both possible and desirable to reduce accident rates to levels approaching zero. Natural disasters remain hazardous, but are extremely infrequent, and at any rate when a deadly earthquake strikes, there are higher priorities than providing alternative passenger rail routes.
This is not to say that redundancy has no uses. Dense subway systems are redundant in the sense of providing multiple routes through the city – although, at the peak, they’re usually all very crowded. This makes it possible to shut down lines off-peak for maintenance; New York and London are both notorious for weekend service changes, and Paris shuts down short segments of lines for maintenance for a few weeks at a time (see for example here). But small subway systems manage to make do with just ordinary overnight shutdowns, and Copenhagen even runs trains 24/7, shutting down one track at a time at night and using the driverless operation to run trains on single track. It’s just more convenient to have more options, but not necessary.
The upshot is that when a subway or mainline rail network chooses where to lay additional lines, it should ignore all needs of redundancy, except possibly as tie-breakers. The benefits are there, but do not outweigh the cost of building less optimal lines. The operator should instead invest in systems, worker training, and maintenance regimes that ensure high reliability, and expand the network based on ordinary criteria of expected ridership and capacity needs. There’s no need to worry about failure, and it’s much better to design the network not to fail in the first place.