This is a theoretical post about a practical matter that arises whenever multiple variables interact. Two variables x and y, both correlated positively a dependent variable z, are said to positively interact if when x is larger, the effect of y on z gets larger and vice versa, and to negatively interact if when x is larger, the effect of y on z gets smaller. If z is transit ridership, let alone any of the direct benefits of good transit (good job access, environmental protection, public health, etc.), then it is affected by a slew of variables concerning service provision, infrastructure, and urban design, and they interact in complex ways.
I have not found literature on this interaction, which does not mean that this literature does not exist. The papers I’ve seen about correlates of bus ridership look at it one variable at a time, and yet they are suggestive of positive as well as negative interactions. More broadly, there are interactions between different types of service.
Positive interactions tend to involve network effects. These include the interaction between transit and transit-oriented development, as well as that between different aspects of rail modernization. Whenever there is positive interaction between variables, half-measures tend to flop; some are a reverse 80/20 situation, i.e. 80% of the cost yields 20% of the benefits. In some cases, compromises are impossible without making service useless. In others, some starter service is still viable, but in its presence, the case for expansion becomes especially strong, which can lead to a natural virtuous cycle.
Negative interactions occur when different improvements substitute for one another. One straightforward example is bus stops and frequency: frequency and the quality of bus shelter both impact bus ridership, but have a negative interaction, in that at higher frequency, the inconvenience coming from not having bus shelter is less important. In some cases, negative interactions can even lead to either/or logic, in which, in the presence of one improvement, another may no longer be worth the economic or political cost. In others it’s still useful to pursue multiple improvements, but the negative interaction implies the benefits are not as great as one might assume in isolation, and transit planners and advocates must keep this in mind and not overpromise.
Door-to-door trip times
The door-to-door trip time includes walking distance to and from the station, waiting time, transferring time, and in-vehicle time. Each of these components affects ridership in that longer trips reduce people’s propensity to choose public transport.
There is strong positive interaction between variables affecting the trip time. This is not directly attested in the literature that I know of, but it is a consequence of any ridership model that lumps the different components of trip time into one. If public transportation runs faster, that is if the in-vehicle time is reduced, then the share of the other components of the trip time rises, which means that the importance of frequency for reducing wait time is increased. Thus, speed and frequency have a positive interaction.
However, at the same time, there is a subtle negative interaction between speed and service provision on buses. The reason is that bus operating expenses are largely a linear function of overall service-hours, since costs are dominated by driver wages, and even maintenance is in practice a function of service-hours and not just service-km, since low speeds come from engine-stressing stop-and-go traffic conditions. In this case, increasing the speed of buses automatically means increasing their frequency, as the same resources are plugged into more service-km. In that case, the impact of a further increase in service is actually decreased: by speeding up the buses, the transit agency has reduced the share of the door-to-door trip time that is either in-vehicle or waiting at a stop, and thus further reductions in wait time are less valuable.
In the literature, the fact that investing in one portion of the trip makes its share of the overall trip length smaller and thus reduces the impact of further investments is seen in research into ridership-frequency elasticity. My standard references on this – Lago-Mayworm-McEnroe and Totten-Levinson – cite lit reviews in which the elasticity is far higher when frequency is low than when it is high, about 1 in the lowest-frequency cases and 0.3 in the highest-frequency ones. When frequency is very low, for example hourly, the elasticity is so high that adding service increases ridership proportionally; when frequency is a bus every few minutes, the impact of service increase on ridership is much smaller.
I’ve focused on in-vehicle time and waiting time, but the other two components are sometimes within the control of the transit agency as well, especially on rapid transit. Station design can reduce transfer time by providing clear, short passageways between platforms; it can also reduce access time by including more exits, for example at both ends of the platform rather than just at one end or in the middle. As such design positively interacts with other improvements to speed, it makes sense to bundle investments into more exits and better transfers with programs that add train service and speed up the trains.
There is positive interaction between different transit services that work together in a network. In the presence of a north-south line through a city, the case for east-west transportation strengthens, and vice versa. This is not a new insight – Metcalfe’s law predicts usage patterns of communications technologies and social networks. The same effect equally holds for fixed infrastructure such as rail, and explains historical growth patterns. The first intercity steam railway opened in 1830, but the fastest phase of growth of the British rail network, the Railway Mania, occurred in the late 1840s, after main lines such as the London and Birmingham had already been established. 150 years later, the first TGV would start running in 1981, but the network’s biggest spurt of growth in terms of both route-km and passenger numbers occurred in the 1990s.
Using a primitive model in which high-speed rail ridership is proportional to the product of city populations, and insensitive to trip length, the United States’ strongest potential line is naturally the Northeast Corridor, between Boston and Washington. However, direct extensions of the line toward Virginia and points south are extremely strong per the same model and, depending on construction costs, may have even higher return on investment than the initial line, as 180 km of Washington-Richmond construction produce 540 km of New York-Richmond passenger revenue. In some places, the extra link may make all the difference, such as extending New York-Buffalo high-speed rail to Toronto; what looks like a basic starter system may be cost-ineffective without the extra link.
Network effects produce positive interactions not just between different high-speed rail lines, but also between transit services at lower levels. Rail service to a particular suburb has positive interaction with connecting bus service, for which the train station acts as an anchor; in some cases, such as the Zurich model for suburban transit planning, these are so intertwined that they are planned together, with timed transfers.
Network effects do not go on forever. There are diminishing returns – in the case of rail, once the biggest cities have been connected, new lines duplicate service or connect to more marginal nodes. However, this effect points out to a growth curve in which the first application has a long lead time, but the next few additions are much easier to justify. This is frustrating since the initial service is hard to chop into small manageable low-risk pieces and may be canceled entirely, as has happened repeatedly to American high-speed rail lines. And yet, getting over the initial hurdle is necessary as well as worth it once subsequent investments pan out.
In the introduction, I gave the example of negative interaction between bus shelter amenities and frequency: it’s good to have shelter as well as shorter waits, but if waits are shorter, the impact of shelter is lessened. There are a number of other negative interactions in transit. While it is good to both increase bus frequency and install shelter at every stop, some negative interactions lead to either-or logic, in which once one improvement is made, others are no longer so useful.
Fare payment systems exhibit negative interactions between various positive features. The way fare payment works in Germany and Switzerland – paper tickets, incentives for monthly passes to reduce transaction costs, proof of payment – is efficient. But the same can be said about the smartcard system in Singapore, EZ-Link. EZ-Link works so rapidly that passengers can board buses fast, which reduces (but does not eliminate) the advantage of proof-of-payment on buses. It also drives transaction costs down to the point of not making a monthly pass imperative, so Singapore has no season passes, and it too works.
Interior circulation displays negative interactions as well. There are different aspects of rolling stock design that optimize for fast boarding and disembarking of passengers, which is of critical importance on the busiest rail lines, even more than interior capacity. Trains so designed have a single level, many doors (four pairs per 20-meter car in Tokyo), interiors designed for ample standing space, and level boarding. Each of these factors interacts negatively with the others, and in cities other than Tokyo, regional trains like this are overkill, so instead designers balance circulation with seated capacity. Berlin has three door pairs per car and seats facing front and back, Zurich has double-deckers with two pairs of triple-wide doors and has been quite tardy in adopting level boarding, Paris has single-level cars with four door pairs and crammed seats obstructing passageways (on the RER B) and bespoke double-deckers with three pairs of triple-wide doors (on the RER A).
Finally, speed treatments on scheduled regional and intercity trains may have negative interactions. The Swiss principle of running trains as fast as necessary implies that once various upgrades have cut a route’s trip time to that required for vigorous network connections – for example, one hour or just a few minutes less between two nodes with timed transfers – further improvements in speed are less valuable. Turning a 1:02 connection into a 56-minute one is far more useful than further turning a 56-minute service into a 50-minute trip. This means that the various programs required to boost speed have negative interactions when straddling the boundary of an even clockface interval, such as just less than an hour, and therefore only the cheapest ones required to make the connections should receive investment.
Good transit advocates should always keep the complexities that affect transportation in mind. Negative interactions between different investments have important implications for activism as well as management, and the same is true for positive interactions.
When variables interact negatively, it is often useful to put a service in the good enough basket and move on. In some cases, further improvements are even cost-ineffective, or require unduly compromising other priorities. Even when such improvements remain useful, the fact that they hit diminishing returns means advocates and planners should be careful not to overpromise. Cutting a two-hour intercity rail trip to an hour is great; cutting a 40-minute trip to a 20-minute one may seem like a game changer, but really isn’t given the importance of access and egress times, so it’s usually better to redeploy resources elsewhere.
Conversely, when variables interact positively, transit service finds itself in an 80% of the cost for 20% of the benefits situation. In such case, compromises are almost always bad, and advocates have to be insistent on getting everything exactly right, or else the system will fail. Sometimes a phased approach can still work, but then subsequent phases become extremely valuable, and it is useful to plan for them in advance; other times, no reasonable intermediate phase exists, and it is on activists to convince governments to spend large quantities of upfront money.
Transportation is a world of tradeoffs, in which benefits are balanced against not just financial costs but also costs in political capital, inconvenience during construction, and even activist energy. Positive and negative interactions have different implications to how people who want to see better public transport should allocate resources; one case encourages insisting on grand plans, another encourages compromise.
California Governor Gavin Newsom spoke his piece, and California HSR is most likely dead. His state of the state speech tried to have it both ways, and his chief of staff insisted that no, he had not just canceled the HSR project, but his language suggests he’s not going to invest any more money or political capital in going beyond the Central Valley. Lisa Schweitzer put it best when she talked about his sense of priorities.
I actually don’t want to talk about the costs of the project; an article about this topic will appear in the Bay City Beacon any day now, and I will update this post with a link when it does. Rather, I want to talk about alignments. For those of you who’ve been reading me since the start, this means reopening some topics that involved tens of thousands of comments’ worth of flamewars on California HSR Blog.
What they should be building
As before, red denotes HSR with top speed of 350 km/h outside the built-up areas of the largest cities, and blue denotes legacy lines with through-service. I ask that people not overinterpret pixel-level alignments. The blue alignment in Southern California is the legacy route taken by Amtrak, the one in the Bay Area is a legacy line from Fremont to San Jose that some area transit advocates want a Caltrain extension on (and if it’s unavailable then it can be deleted with a forced transfer to BART), the one in the far north of the state is the freight line up to Redding.
The mid-2000s environmental impact study claims that Los Angeles-San Francisco via Altamont Pass would take 2:36 nonstop. The Tejon route I’m drawing is 12 minutes faster, so in theory this is 2:24. But three express stops in the middle, even in lower-speed territory right near Los Angeles and San Francisco, lead to somewhat longer trip times, as do various design compromises already made to reduce costs. My expectation is that the alignment drawn is about 2:45 on LA-SF and somewhat less on LA-Sacramento, on the order of 2:15 nonstop.
Why Tejon and not the Tehachapis
There are two ways to get between Los Angeles and Bakersfield. The first is the alignment taken by the I-5, called the Grapevine or Tejon Pass. The second is to detour far to the east via Palmdale and Tehachapi Pass. The alignment I drew is Tejon, that chosen by the HSR Authority is the Tehachapis.
Clem Tillier made a presentation about why Tejon is far superior. It is shorter, reducing trip times by about 12 minutes. It is less expensive, since the shorter length of the route as well as the reduced tunneling requirement means fewer civil structures are required; Clem’s presentation cites a figure of $5 billion, but with recent overruns I’ve heard a figure closer to $7 billion.
The exact cost of either alignment depends on standards. Unlike Northeastern passenger rail efforts, which are based on bad American design standards that recommend very shallow grades, ideally no more than 1.5-2%, California HSR uses a generic European standard of up to 3.5%, the same as in France. However, 3.5% is a conservative value, designed around TGVs, which almost uniquely in the HSR world have separate power cars. Distributed traction, that is EMUs, has higher initial acceleration and can climb steeper grades. One German HSR line goes up to 4%, and only the EMU ICE 3 train is allowed to use it, not the ICE 1 and 2, which have power cars like the TGVs. Even 5% is achievable far from stations and slow zones, which would reduce tunneling requirements even further.
In the mid-2000s, it was thought that the Tehachapi alignment could be done with less tunneling than Tejon. Only one 3.5% alignment through Tejon was available without crossing a fault line underground, so Tehachapi seemed safer. But upon further engineering, it became clear more tunneling was needed through Soledad Canyon between Los Angeles and Palmdale, while the Tejon alignment remained solid. The HSR Authority resisted the calls to shift to Tejon, and even sandbagged Tejon in its study, for two reasons:
1. Los Angeles County officials favored the Tehachapi route in order to develop Palmdale around the HSR station.
2. A private real estate company called Tejon Ranch planned to build greenfield development near the Tejon HSR route called Tejon Mountain Village, and opposed HSR construction on its property.
As Clem notes, the market capitalization of Tejon Ranch is about an order of magnitude less than the Tehachapi-Tejon cost difference. As for the county’s plans for Palmdale, spending $5 billion on enabling more sprawl in Antelope Valley is probably not the state’s highest priority, even if an HSR station for (optimistically) a few thousand daily travelers in a region of 400,000 exists to greenwash it.
Why follow the coast to San Diego
Two years ago I wrote an article for the Voice of San Diego recommending electrifying the Los Angeles-San Diego Amtrak line and running trains there faster, doing the trip in about 2 hours, or aspirationally 1:45. Amtrak’s current trip time is 2:48-2:58 depending on time of day.
The alignment proposed by the HSR Authority instead detours through the Inland Empire. The good thing about it is that as a greenfield full-speed route it can actually do the trip faster than the legacy coast line could – the plan in the 2000s was to do it in 1:18, an average speed of about 190 km/h, on account of frequent curves limiting trains to about 250 km/h. Unfortunately, greenfield construction would have to be postponed to phase 2 of HSR, after Los Angeles-San Francisco was complete, due to costs. Further design and engineering revealed that the route would have to be almost entirely on viaducts, raising costs.
If I remember correctly, the estimated cost of the HSR Authority’s proposed alignment to San Diego was $10 billion in the early 2010s, about $40 million per kilometer (and so far Central Valley costs have been higher). Even excluding the Los Angeles-Riverside segment, which is useful for HSR to Phoenix, this is around $7 billion for cutting half an hour out of trips from Los Angeles and points north to San Diego. Is it worth it? Probably not.
What is more interesting is the possibility of using the Inland Empire detour to give San Diego faster trips to Phoenix and Las Vegas. San Diego-Riverside directly would be around 45 minutes, whereas via Los Angeles it would be around 2:20.
However, the same question about the half hour’s worth of saving on the high-speed route can equally be asked about connecting San Diego to Las Vegas and Phoenix. These are three not especially large, not especially strong-centered cities. The only really strong center generating intercity travel there is the Las Vegas Strip, and there San Diego is decidedly a second-order origin compared with Los Angeles; the same is even true of San Francisco, which could save about 40 minutes to Las Vegas going via Palmdale and Victorville, or 55 minutes via Mojave and Barstow.
Ultimately, the non-arboreal origin of money means that the $7 billion extra cost of connecting Riverside to San Diego is just too high for the travel time benefits it could lead to. There are better uses of $7 billion for improving connectivity to San Diego, including local rail (such as a light rail tunnel between city center and Hillcrest, branching out to Mid-City and Kearny Mesa) and a small amount of extra money on incrementally upgrading the coast line.
Why Altamont is better than Pacheco
I’m leaving the most heated issue to last: the route between the Central Valley and the Bay Area. I am not exaggerating when I am saying tens of thousands of comments have been written in flamewars on California HSR Blog over its ten years of existence; my post about political vs. technical activists treated this flamewar as almost a proxy for which side one was on.
The route I drew is Altamont Pass. It carries I-580 from Tracy to Livermore, continuing onward to Pleasanton and Fremont. It’s a low pass and trains can go over the pass above-ground, and would only need to tunnel further west in order to reach Fremont and then cross the Bay to Redwood City. Many variations are possible, and the one studied in the mid-2000s was not the optimal one: the technical activist group TRANSDEF, which opposes Pacheco, hired French consultancy SETEC to look at it and found a somewhat cheaper and easier-to-construct Altamont alignment than the official plan. The biggest challenge, tunneling under the Bay between Fremont and Redwood City, is parallel to a recently-built water tunnel in which there were no geotechnical surprises. Second-hand sources told me at the beginning of this decade that such a rail tunnel could be built for $1 billion.
Pacheco Pass is far to the south of Altamont. The route over that pass diverges from the Central Valley spine in Chowchilla, just south of Merced, and heads due west toward Gilroy, thence up an alignment parallel to the freight line or US 101 to San Jose. The complexity there is that the pass itself requires tunneling as the terrain there is somewhat more rugged than around Altamont.
As far as connecting Los Angeles and San Francisco goes, the two alignments are equivalent. The old environmental impact reports stated a nonstop trip time of 2:36 via Altamont and 2:38 via Pacheco; Pacheco is somewhat more direct but involves somewhat more medium-speed running in suburbia, so it cancels out. The early route compromises, namely the Central Valley route, affected Altamont more than Pacheco, but subsequent compromises in the Bay Area are the opposite; nonetheless, the difference remains small. However, Pacheco is superior for service between Los Angeles and San Jose, where it is about 10 minutes faster, while Altamont is superior for service between the Bay Area and Sacramento, where it is around an hour faster and requires less additional construction to reach Sacramento.
As with the Tehachapis, the Authority sandbagged the alignment it did not want. San Jose-based HSR Authority board member Rod Diridon wanted Pacheco for the more direct route to Los Angeles, perhaps realizing that if costs ran over or the promised federal and private funding did not materialize, all three of which would indeed happen, the spur to San Jose was the easiest thing to cut, leaving the city with a BART transfer to Fremont. Consequently, the Authority put its finger on the study’s scale: it multiplied the frequency effect on passenger demand by a factor of six, to be able to argue that splitting trains between two Bay Area destinations would reduce ridership; it conducted public hearings in NIMBY suburbs near Altamont but not in ones near Pacheco; and early on it even planned to build San Francisco-San Jose as its first segment, upgrading Caltrain in the meantime.
And as with the Tehachapis, the chosen route turned out to be worse than imagined. Subsequent business plans revealed more tunneling was needed. The route through San Jose itself was compromised with curvy viaducts, and the need to blend regional and intercity traffic on the Caltrain route forced further slowdowns in intercity train speed, from a promised 30 minutes between San Francisco and San Jose to about 45. The most recent business plan even gave up on high speed between Gilroy and San Jose and suggested running on the freight mainline in the initial operating stage, at additional cost and time given Union Pacific’s hostility to passenger rail.
What is salvageable?
The HSR Authority has made blunders, perhaps intentionally and perhaps not, that complicate any future project attempting to rescue the idea of HSR. In both Los Angeles and the Bay Area, delicate timetabling is needed to blend regional and intercity rail. Heavy freight traffic interferes with this scheduling, especially as Union Pacific demands unelectrified track, generous freight slots, and gentle grades for its weak diesel locomotives, frustrating any attempt to build grade-separations cheaply by using 3-4% grades. Caltrain’s trackage rights agreement with UP contained a guillotine clause permitting it to kick freight off the line if it changed in favor of an incompatible use, originally intended to permit BART to take over the tracks; Caltrain gave up this right. UP is not making a profit on the line, where it runs a handful of freight trains per day, but the industrial users insisted on freight rail service.
Likewise, the Central Valley segment has some route compromises baked in, although these merely raise costs rather than introducing forced slowdowns or scheduling complications. A future project between Merced, the northern limit of current construction, and Sacramento, could just spend more time early on negotiating land acquisitions with the farmers.
It is in a way fortunate that in its incompetence, the HSR Authority left the most important rail link in the state – Los Angeles-Bakersfield – for last. With no construction on the Tehachapi route, the state will be free to build Tejon in the future. It will probably need to buy out Tejon Mountain Village or add some more tunneling, but the cost will still be low compared with that of the Palmdale detour.
Ultimately, the benefits of HSR increase over time as cities increase in size, economic activity, and economic connectivity. The Shinkansen express trains ran hourly in 1965; today, they run six times per hour off-peak and ten at the peak. Going back even earlier, passenger traffic on the London Underground at the beginning of the 20th century was not impressive by today’s standards. The fact that national rail traffic plummeted in most developed countries due to the arrival of mass motorization should not distract from the fact that overall travel volumes are up with economic growth, and thus, in a growing area, the case for intercity rail investment steadily strengthens over time.
Chickenshit governors like Newsom, Andrew Cuomo, and Charlie Baker are not an immutable fact of life. They are replaced after a few terms, and from time to time they are replaced by more proactive leaders, ones who prefer managing big-ticket public projects successfully to canceling them or scaling them back on the grounds that they are not competent enough to see them through.
Yesterday, I tweeted this proposal for a high-speed rail network for the eastern half of the United States:
I’d like to go over what the map means and address questions that have appeared on Twitter.
The color scheme
Red denotes high-speed lines, with a top speed in the 300-360 km/h range, not including the occasional enforced slow zone. The average speed would be around 225-250 km/h in the Northeast, where the routes are all compromised by existing infrastructure, and 300 km/h in the Midwest, where flat expanses and generous rail rights-of-way into the major cities should allow the same average speeds achieved in China. The South is intermediate, due to the rolling terrain and extensive suburban sprawl in the Piedmont.
Yellow denotes high-speed lines as well, but they are more marginal (in the linked tweet this is purple, but yellow is friendlier to the colorblind). This means that I expect much lower social return on investment there, so whether these lines could succeed depends on the price of fuel, trends in urban sprawl, and construction costs within the normal first-world range. Some of these lines, namely Atlanta-New Orleans and the connection from Savannah to Jacksonville, should be legacy lines if HSR does not pan out; others, like Kansas City-Oklahoma City, are unlikely to be worth it.
Blue denotes legacy lines that are notable for the network. It does not include the entire set of legacy intercity lines the US should be running, but does include all lines that I believe should get through-service to high-speed lines; but note that some lines, like Minneapolis-Duluth and Charleston-Greenville, do not have through-service. Some of these lines are potentially very strong, like New Haven-Springfield as a Northeast Corridor extension. Others are marginal, like Binghamton-Syracuse, which Adirondacker has recurrently criticized in comments on the grounds that New York-Syracuse is much faster on HSR and the intermediate cities are too small to justify more than a bus.
This is not meant to be an exhaustive list. Some of the alignments may not be optimal, and one of the red lines, Albany-Montreal, can plausibly be reclassified as yellow due to the weakness of travel markets from the United States to Montreal.
The schedules I’m proposing are fast – all faster than in Germany and Italy, many faster than in France and Spain. The reason for this is the long expanses between American cities. Germany and Italy have high population density, which is in theory good for HSR, but in practice means the closely-spaced cities yields lines with a lot of route compromises. In Britain people who advocate for the construction of High Speed 2 complain that England’s population density is too high, making it harder to build lines through undeveloped areas (that is, farms) between big cities the way France and Spain did.
Out of New York, the target trip times are:
- Boston: 1:40
- Philadelphia: 0:40
- Washington: 1:35
- Albany: 0:55, an hour minus half a turnaround time, useful for Swiss run-trains-as-fast-as-necessary timetabling
- Syracuse: 1:50
- Rochester: 2:25
- Buffalo: 2:45
- Toronto: 3:20
- Harrisburg: 1:20
- Pittsburgh: 2:30
- Cleveland: 3:10
- Richmond: 2:15
- Raleigh: 3:10
- Charlotte: 4:05
- Atlanta: 5:30
- Birmingham: 6:15, probably no direct service from New York except at restricted times of day, but hourly or 30-minute service to Atlanta
Out of Chicago, they are:
- Milwaukee: 0:30
- Minneapolis: 2:30
- St. Louis: 1:30
- Kansas City: 2:50
- Indianapolis: 0:55
- Cincinnati: 1:30
- Louisville: 1:35
- Nashville: 2:35
- Atlanta: 4:00
- Toledo: 1:15
- Detroit: 1:35
- Toronto: 2:55
- Cleveland: 1:50
- Buffalo: 2:50
For the most part, there should be a stop in each metropolitan area. What counts as a metropolitan area remains a question; truly multicore regions can get one stop per core, for example there should definitely be a stop in Newark in addition to New York, and South Florida should have individual stops for Miami, Fort Lauderdale, and West Palm Beach. On the Northeast Corridor, what I think the optimal express stopping pattern is is one stop per state, with additional local trains making some extra stops like New London, Stamford, New Rochelle, and Trenton; Wilmington can be a local or an express stop – whether the infrastructure required to skip it at speed is worth it is a close decision.
On most lines, multiple stopping patterns are unlikely to be worth it. The frequency wouldn’t be high in the first place; moreover, the specific stations that are likely candidates for local stops are small and medium-size cities with mostly short-range travel demand, so serving them on a train stopping less than hourly is probably not going to lead to high ridership. Among the lines coming out of Chicago, the only one where I’m comfortable prescribing multiple stopping patterns is the one headed east toward Cleveland and Detroit.
Another consideration in the stop spacing is where most passengers are expected to travel. If there is a dominant city pair, then it can get express trains, which is the justification for express trains on the Northeast Corridor and on Chicago-Detroit and Chicago-Cleveland. However, in Upstate New York, there is no such dominant city pair: travel demand from New York to Toronto is not much more than to Buffalo (the air travel market is around a million people annually, whereas New York-Buffalo is 600,000) even though Toronto is a lot bigger, so there’s little point in skipping Syracuse, Rochester, and Buffalo to speed up end-to-end trips.
Ultimately, stops don’t cost that much time. In 360 km/h territory, a late-model Shinkansen has a stop penalty of a little under 3 minutes excluding dwell time – figure about 4 minutes with dwell. Those minutes add up on short-range lines with a lot of stops, but as long as it’s restricted to about a stop every 150 km or more in high-speed territory, this should be fine.
Highland gaps in service
Several people on Twitter complained about the lack of service to West Virginia and Arkansas. West Virginia is a politically distinguished part of the US nowadays, a metonym for white working-class decline centered on the coal industry, and as a result people notice it more than they do Midwestern poverty, let alone Southern or Western poverty. Poor cities are often served by red lines on my map, if they are between larger cities: Youngstown and Bowling Green are both noticeably poorer than Charleston, West Virginia, and Lafayette, Killeen-Temple, and Erie are barely richer. In the West, not depicted on my map, Pueblo, Chico, and Redding are all as poor as Charleston and are on standard wishlists for upgraded legacy rail while Tucson is a hair poorer and probably should get a full HSR extension of Los Angeles-Phoenix.
The reason Appalachia is underserved is the highland topography. Construction costs go up sharply once tunnels are needed; the route through Pennsylvania connects New York and Philadelphia with Pittsburgh, Cleveland, Detroit, and Chicago, which are big enough urban centers to justify the expense, but additional routes would connect smaller cities. Washington awkwardly gets poor service to the Midwest; a yellow line between Baltimore and Harrisburg may be prudent, but a blue line is not, since the legacy line is so curvy that a high-speed detour through Philadelphia would still be faster. The Piedmont South gets a red line parallel to the mountains and some branches, but nothing that justifies going over the mountains.
Legacy rail additions are still plausible. Amtrak connects Charleston with Cincinnati in 5 hours, but cutting this to about 3.5 should probably be feasible within existing right-of-way, provided CSX does not mind faster passenger rail on its tracks; thence, Chicago-Cincinnati would take around 1.5 hours. However, the negotiations with CSX may be difficult given the line’s use by slow, heavy freight; the blue lines shown on my map are mostly not important freight mainlines.
In Arkansas, the question is whether a line to Little Rock is justifiable. The yellow route between Atlanta and Dallas could plausible detour north through Memphis and Little Rock instead of the depicted direct alignment; Atlanta-Dallas is about the same distance as New York-Chicago, a trip of about 5 hours, so the line would have to survive based on intermediate markets, making the less direct route better. On the other hand, Memphis and Little Rock are small, and while Atlanta and Dallas are big, they’re nowhere near the size of New York, and have very weak centers, encouraging driving rather than riding paid transportation whether it’s a train or plane.
Regional rail additions
As I said above, the blue line list is not intended to be exhaustive. I suspect it is exhaustive among long-range intercity lines, not counting yellow routes like Dallas-Oklahoma City or Atlanta-New Orleans. I was specifically asked about Amtrak’s City of New Orleans route, connecting Chicago, St. Louis, Memphis, and New Orleans, since there is no trace of it on the map beyond the Chicago-St. Louis HSR. There could certainly be a high-speed line down to Memphis, which would place the city around 3 hours from Chicago. However, Memphis is not a large city; St. Louis, Memphis, and New Orleans have all stagnated in the last hundred years, making them weaker candidates for HSR than they were for legacy rail in the postwar era.
In contrast with the deliberate omission of the City of New Orleans routes, there are many regional lines that could be added. In the Northeast, a number of lines are every bit as valuable candidates for a national map as Boston-Portland, including Boston-Cape Cod, Boston-Manchester, New York-Allentown, Philadelphia-Allentown, and maybe Syracuse-Watertown with a timed HSR connections. Boston-Portland could have through-service to the Northeast Corridor or it could not, depending on timetabling in the North-South Rail Link tunnel; my current position is that it should only have through-service to other regional lines, but it’s a close decision.
Outside the Northeast there may be strong in-state networks. I showed the one in South Carolina since it substitutes for lines that I think are just a little too weak to even be in yellow, connecting North Carolina directly with Jacksonville, as well as the one in Wisconsin, based on through-service to HSR to Chicago. But Michigan can have an in-state network, either electrified or unelectrified, connecting cities orthogonally to HSR, and maybe also an electrified spine running the current Wolverines route with through-service to HSR. Indiana can have interregional lines from Indianapolis to outlying cities, but there would need to be more stuff in the center of Indianapolis for such service to attract drivers. Florida has some decent regional lines, even with how unusually weak-centered its cities are, for example Tampa-St. Petersburg and Tampa-Sarasota.
In a few places, the alignment is either vague or questionable. In the Northeast the biggest question is whether to serve Hartford on the mainline. I dealt with that issue years ago, and my answer has not changed: probably not. The second biggest is which alignment to take across the Appalachians in Pennsylvania; this requires a detailed engineering survey and the line I drew is merely a placeholder, since further design is required to answer questions about the precise costs and benefits of serving intermediate cities like State College and Altoona.
By far the biggest criticism I’ve gotten about macro alignment concerns how to get between the Midwest and the Northeast. The alignment I drew connects Chicago with points east via Cleveland. Due to the decline of Cleveland and slow growth of Columbus in its stead, multiple people have posited that it’s better to draw the red line well to the south, passing via Fort Wayne and Columbus. This would give Columbus fast service to Chicago, in not much more than 1:30, and also connect Pittsburgh better with Columbus, Cincinnati, and plausibly Louisville.
The problem with the Columbus route is that Detroit exists. The drawn alignment connects Pittsburgh with Detroit in about 1:35 and New York with Detroit in about 4:05, in addition to the fast connection to Chicago. A legacy connection in Fort Wayne would slow Chicago-Detroit to about 2:50, nearly doubling the trip time between the Midwest’s two largest cities; it would lengthen New York-Detroit to around 6 hours via Pennsylvania; the route via Canada would take a little more than 4 hours, but might not even exist without the ability to connect it west to Chicago – Canadian HSR studies are skeptical about the benefits of just Toronto-Windsor.
In contrast, the new city pairs opened by the Columbus alignment, other than Chicago-Columbus, involve small, weak-centered cities. Detroit is extremely weak-centered as well, but Chicago and New York are not, which means that suburban drivers will still drive to the train station to catch a ride to Chicago or New York if HSR is available; in contrast, city pairs like Pittsburgh-Cincinnati are very unlikely to get substantial rail mode share without completely revamping the way the geography of jobs in American cities is laid out.
Changing the geography of the nation
In one of the interminable Green New Deal papers, there was some comment about having HSR obviate the need for air travel. This proposition is wrong and misses what makes HSR work here and in Japan, South Korea, and China. The median distance of a domestic American air trip is well above the point beyond which HSR stops being competitive with air travel.
Counting only city pairs at a plausible HSR range of around 4-5 hours, maybe a bit more for New York-Atlanta, my estimate is that about 20-25% of domestic US air trips can be substituted by rail. This excludes city pairs at plausible HSR distance on which there will never be any reason to build HSR, like El Paso-Albuquerque, Minneapolis-Denver, and Charlotte-Columbus. Higher-end estimates, closer to 25% than to 20%, require all the yellow lines and a few more, as well as relying on some long-range city pairs that happen to be on the way of relatively direct HSR and have no direct air traffic.
However, the fact that people will continue flying until vactrains are invented does not make HSR useless or unnecessary. After all, people fly within Europe all the time, even within individual countries like France. Not only do people fly within Japan, but also the country furnishes two of the world’s top air routes in Tokyo-Sapporo and Tokyo-Fukuoka. As an alternative at its optimum range of under about 1,000 km, HSR remains a solid mode of travel.
Moreover, HSR has a tendency to change the geography of the nation. In France and Japan, it’s helped cement the capital’s central location in national economic geography. Tokyo and Paris are the world’s top two cities in Fortune Global 500 headquarters, not because those cities have notable economic specialization like New York but because a large company in Japan and France will usually be headquartered in the capital.
The likely impact of HSR on the US is different, because the country is too big for a single city’s network. However, the Midwest is likely to become a more tightly integrated network focused on Chicago, Texas and Florida are likely to have tighter interconnections between their respective major cities, and the links between the Piedmont South and the Northeast are likely to thicken. HSR cannot supplant air travel at long distances, but it can still create stronger travel volumes within its service range, such that overall trip numbers will be much higher than those of air travel, reducing the latter’s relative importance.
I am wrapping up a project to look at speedup possibilities for trains between New York and New Haven; I’ll post a full account soon, but the headline result is that express trains can get between Grand Central and New Haven in a little more than an hour on legacy track. In this calculation I looked at speed zones imposed by the curves on the line. The biggest possible speedups involve speed limits that are not geometric – and those in turn come from some very sharp slow zones. The worst is the Grand Central station throat, and I want to discuss that in particular since fixing the slowest zones usually yields the most benefits for train travel times.
Best practice for terminal approaches
Following Richard Mlynarik’s attempt to rescue the Downtown Extension in San Francisco, I’ve assumed that trains can approach terminals at 70 km/h, based on German standards. At this speed, an EMU on level track can stop in about 150 meters. In Paris, the excellent Carto Metro site details speed limits, and at most terminals with bumper tracks the speed limit is 60 km/h, with a few going up to 100 km/h.
Even with bumper tracks, 70 km/h can be supported, provided the train is not intended to stop right at the bumpers. At a fixed speed, the deceleration distance is the inverse of the deceleration rate. There is some variation in braking performance, but it’s in a fairly narrow range; on subway trains in New York, everything is supposed to brake at the same nominal rate of 3 mph/s, or 1.3 m/s^2, and when trains brake more slowly it’s because of a deliberate decision to avoid wearing the brakes out. As long as the train stops 1-2 car lengths away from the bumpers, as is routine on Metro-North, the variation will be much smaller than the margin of safety.
Fast movement through the station throat is critical for several reasons. First, as I’ll explain below, sharp speed limits have an outsize effect on trip times, and can be fixed without expensive curve easements or top-rate rolling stock. And second, at train stations with a limited number of tracks, the station throat is the real limiting factor to capacity, since trains would be moving in and out frequently, and if they move too slowly, they’ll conflict. With its 60 km/h throat, Saint-Lazare on the RER E turns 16 trains per hour at the peak on only four tracks.
I had a conversation with other members of TransitMatters in Boston yesterday, in which we discussed work to be done for our regional rail project. One of the other members, I forget who, asked me, do European train protection systems shut down in station throats too?
The answer to the question is so obviously yes that I wanted to understand why anyone would ask it. Apparently, the American mandate for automatic train protection on all passenger rail lines, under the name positive train control, or PTC, is only at speeds higher than 10 miles per hour. At 10 mph or less train operators can drive the train by sight, and no signaling is required, which is why occasionally trains overrun the bumpers even on PTC-equipped lines if the driver has sleep apnea.
Without video, nobody could see the facial expressions I was making. I believe my exact words were “…What? No! What? What the hell?”.
The conversation was about South Station, but the same situation occurs at Grand Central. Right-of-way geometry is good for decent station approach speed – there is practically no limit at Grand Central except tunnel clearances, which should be good for 100 km/h, and at South Station the sharp curve into the station from the west is still good for around 70 km/h given enough superelevation.
The impact of slow zones near stations
Last year, I published code for figuring out acceleration penalties based on prescribed train characteristics. The relevant parameters for Metro-North’s M8 is initial acceleration = 0.9 m/s^2, power/weight = 12 kW/t. Both of these figures are about two-thirds as high as what modern European EMUs are capable of, but it turns out that at low speed it does not matter too much.
Right now the Grand Central throat has a 10 mph speed limit starting just north of 59th Street, just south of milepoint 1. The total travel time over this stretch is 6 minutes, a familiar slog to every regular Metro-North rider; overall, the schedule between Grand Central and Harlem-125th Street is 10 minutes northbound and 12-13 minutes southbound, the difference coming from schedule padding. The remaining 65 or so blocks are taken at 60 mph, nearly 100 km/h, and take around 4 minutes.
Now, let’s eliminate the slow zone. Let trains keep cruising at 100 km/h until they hit the closer-in parts of the throat, say the last kilometer, where the interlocking grows in complexity and upgrading the switches may be difficult; in the last kilometer, let trains run at 70 km/h. The total travel time in the last mile now shrinks to a minute, and the total travel time between Grand Central and Harlem shrinks to 5 minutes and change. Passengers have gained 5 minutes based on literally the last mile.
For the same reason, the Baltimore and Potomac Tunnel imposes a serious speed limit – currently 30 mph through the tunnel, lasting about 2 miles; removing this limit would cut 2-2.5 minutes from the trip time, less than Grand Central’s 5 because the speed limit isn’t as wretched.
The total travel time between New York and New Haven on Metro-North today is about 1:50 off-peak, on trains making all stops north of Stamford. My proposed schedule has trains making the same stops plus New Rochelle doing the trip in 1:23. Out of the 27-28 minutes saved, 5 come from the Grand Central throat, the others coming from higher speed limits on the rest of the route as well as reduced schedule padding; lifting the blanket 75 mph speed limit in Connecticut is only worth about 3 minutes on a train making all stops north of Stamford, and even on an express train it’s only worth about 6 minutes over a 73 kilometer stretch.
What matters for high-speed travel
High-speed rail programs like to boast about their top speeds. But in reality, the difference between a vanilla 300 km/h train and a top of the line 360 km/h only adds up to a minute every 30 kilometers, exclusive of acceleration time. Increasing top speed is still worth it on lines with long stretches of full-speed travel, such as the Tohoku Shinkansen, where there are plans to run trains at 360 over hundreds of kilometers once the connection to Hokkaido reaches Sapporo. However, ultimately, all this extra spending on electricity and noise abatement only yields a second-order improvement to trip times.
In contrast, the slow segments offer tremendous opportunity if they are fixed. The 10 mph limit in the immediate Penn Station throat slows trains down by around 2 minutes, and those of Grand Central and South Station slow trains by more. A 130 km/h slog through suburbia where 200 km/h is possible costs a minute for every 6.2 km, which easily adds up to 5 minutes in a large city region like Tokyo. An individual switch that imposes an undue speed limit can meaningfully slow the schedule, which is why the HSR networks of the world invented high-speed turnouts.
Richard Mlynarik notes that in Germany, the fastest single end-to-end intercity rail line used to be Berlin-Hamburg, a legacy line limited to 230 km/h, where trains averaged about 190 km/h when Berlin Hauptbahnhof opened (they’ve since been slowed and now average 160). Trains go at full speed for the entire way between Berlin and Hamburg, whereas slow urban approaches reduce the average speed of nominally 300 km/h Frankfurt-Cologne to about 180, and numerous compromises reduce that of the nominally 300 km/h Berlin-Munich line to 160; even today, trains from Berlin to Hamburg are a hair faster than trains to Munich because the Berlin-Hamburg line’s speed is more consistent.
The same logic applies to all travel, and not just high-speed rail. The most important part of a regional railway to speed up is the slowest station throats, followed by slow urban approaches if they prove to be a problem. The most important part of a subway to speed up is individual slow zones at stations or sharp curves that are not properly superelevated. The most important part of a bus trip to speed up is the most congested city center segment.
One of my go-to datasets for analyzing American intercity traffic is the Consumer Airfare Report. It reports on average airfares paid for domestic airline traffic, and on the way gives exact counts for O&D traffic between any pair of cities in the contiguous United States. Six and a half years ago I used this dataset to look at potential demand for high-speed rail, back when high-speed rail was still a topic of conversation in American politics, and a few days ago I got curious and looked again.
Unfortunately, the Consumer Airfare Report is no longer available as an easily downloadable table, due to web design horror. The relevant table, Table 6, used to be downloadable per quarter; today the only version lumps all data going back to 1996 and is 100 MB. Here are two cleaned up versions in .ods format, one a 40 MB table going back to 1996 and one an 800 KB table of just the most recent quarter available, the second quarter of 2018. The files lump all airports in a metro area together, such as JFK and Newark, and reports data in ridership per day; be aware that in the smaller file I repeat every city pair, one for each direction, making it easy to sort by city to figure out each city’s total air traffic, which means that just summing up ridership for all city pairs together yields double the actual traffic. In this post I’m going to compare data from 2018 to data from 2011, the year used in my previous post.
Air traffic is increasing
In 2011 Q3, the total volume of domestic air traffic in the US was 1,020,673 per day. By 2018 Q2, it had risen to 1,303,397. A small proportion of this increase is seasonality – Q2 is the busiest – but most of it is real. Here is a table of air traffic and average distance flown (in miles) by quarter:
Long-distance air traffic is especially increasing
The proposition of high-speed rail is that it can replace short-haul flights. A plane averages about 1,000 km/h but incurs considerable taxi, takeoff, and landing time, and passengers also have considerable airport access and egress times, including security and other queues. High-speed trains average about 200-250 km/h, but need no security – a well-run system allows passengers to show up at the station less than five minutes before the train departs – and have much shorter access and egress times as stations are located near city centers.
The above table shows a small increase in average distance flown, about 2% since 2011. However, this masks patterns in the largest cities. New York-Los Angeles traffic grew 30%, compared with 23% in national traffic growth; it is now barely behind New York-Miami (with West Palm Beach separated out) for third busiest American air city pair, the first being far and away Los Angeles-San Francisco.
We can look at the change in the proportion of traffic that can be served by HSR in the largest six American air markets since 2011; consult my post from 2012 for the exact definitions of which corridors count within which buckets – there are some revisions and fixed to be made, but I’ve not done them in order to keep the list of city pairs constant. Las Vegas is no longer ahead of Boston, and Dallas is a fraction of a percent below Boston as of 2018.
|City||Traffic (2011 Q3)||Traffic (2018 Q2)||< 3:00 (2011)||< 3:00 (2018)||< 5:00 (2011)||< 5:00 (2018)|
In the East, short-distance markets have shrunk, in relative terms. Observe that in Chicago the entire difference is within the 3-hour radius, including the spokes of any Midwest HSR network, where air travel has srhunk 12.6% in absolute terms, whereas the 3-to-5-hour annulus, including farther away cities like Atlanta and New York, has not only grown but kept up with Chicago’s overall domestic air travel volumes. But in New York, Washington, and Boston, both the 3-hour radius and the 3-to-5-hour annulus have shrunk, reflecting flights to intermediate Midwestern cities east of Chicago as well as to the South; Boston’s 3-to-5-hour annulus has shrunk 6% in absolute terms.
California holds steady
Since 2011 there has been an increase in air travel to California, especially San Francisco. Los Angeles-San Francisco, once the second largest air market in the US behind New York-Miami, is now far ahead of it, and on its strength, the share of air travel out of Los Angeles and San Francisco that’s within HSR radius has held up.
California’s HSR problems are not about whether there’s demand for such infrastructure. There clearly is. The problems are exclusively about construction costs. But as the state’s economy grows, demand for internal travel is increasing, making HSR a better proposition.
What does this mean for HSR?
The cynical answer is nothing, because in an America where even high-spending Green New Deal proposals neglect HSR and focus on electric cars, it’s unlikely there will be a political effort to build anything. Even Amtrak seems content with justifying capital expense on grounds of climate adaptation rather than reducing trip times.
That said, in the event of a concerted national effort to build HSR, the changes in travel patterns this decade suggest some changes on the margins. California and Texas grow in value while the Midwest falls in value.
In the Midwest, the core lines remain strong, but more peripheral Midwestern lines, say a bypass around Chicago for cross-regional traffic or improved rail service due west toward Iowa, are probably no longer worth it. The Cleveland-Columbus-Cincinnati corridor may not be worth it to build as full HSR – instead it may be downgraded to an electrified passenger-primary corridor (as I understand it it already has very little freight).
There is asymmetry in this situation in that there aren’t a lot of peripheral lines in California and Texas that are becoming interesting now that these states’ economies are bigger than they were when rail advocates first came up with maps in the late 2000s. There is still far too little traffic to justify stringing HSR from Las Vegas to Salt Lake City or from Sacramento to Portland under the mountains. In Texas, there has been a shift from the T-bone alignment to a more triangle-shaped network, since a direct Dallas-Houston line is already under construction, but beyond the Texas triangle, tails like Dallas-Oklahoma City and Houston-New Orleans aren’t getting stronger – Houston-New Orleans air travel volumes are actually down from 2011, though Dallas-New Orleans volumes are up.
The core lines, of course, don’t change. The Northeast Corridor is still the most important corridor, the next most important are still tie-ins extending it to the south and west, and the following is still California HSR. But the dreams of a nationally connected network, or at least a connected network in the eastern two-thirds of the US, should be cast aside – the in-between links, always peripheral, have weakened in this decade.
Six and a half years ago, the Federal Railroad Administration announced that it was going to revise its passenger train regulations. The old regulations required trains to be unusually heavy, wrecking the performance of nearly every piece of passenger rolling stock running in the United States. Even Canada was affected, as Transport Canada’s regulations mirrored those south of the border. The revision process came about for two reasons: first, the attempt to apply the old rules to the Acela trains created trains widely acknowledged to be lemons and hangar queens (only 16 out of 20 can operate at any given time; on the TGV the maximum uptime is 98%), and second, Caltrain commissioned studies that got it an FRA waiver, which showed that FRA regulations had practically no justification in terms of safety.
The new rules were supposed to be out in 2015, then 2016, then 2017. Then they got stuck in presidential administration turnover, in which, according to multiple second-hand sources, the incoming Republican administration did not know what to do with a new set of regulations that was judged to have negative cost to the industry as it would allow more and lower-cost equipment to run on US tracks. After this limbo, the new rules have finally been published.
What’s in the new regulations?
The document spells out the main point on pp. 13-20. The new rules are similar to the relevant Euronorm. There are still small changes to the seats, glazing, and emergency lighting, but not to the structure of the equipment. This means that unmodified European products will remain illegal on American tracks, unlike the situation in Canada, where the O-Train runs unmodified German trains using strict time separation from freight. However, trains manufactured for the needs of the American market using the same construction techniques already employed at the factories in France, Germany, Switzerland, and Sweden should not be a problem.
In contrast, the new rules are ignoring Japan. The FRA’s excuse is that high-speed trains in Japan run on completely dedicated tracks, without sharing them with slower trains. This is not completely true – the Mini-Shinkansen trains are built to the same standards as the Shinkansen, just slightly narrower to comply with the narrower clearances on the legacy lines, and then run through to legacy lines at lower speed. Moreover, the mainline legacy network in Japan is extremely safe, more so than the Western European mainline network.
On pp. 33-35, the document describes a commenter who most likely has read either my writings on FRA regulations or those of other people who made the same points in 2011-2, who asked for rules making it possible to import off-the-shelf equipment. The FRA response – that there is no true off-the-shelf equipment because trains are always made for a specific buyer – worries me. The response is strictly speaking true: with a handful of exceptions for piggybacks, including the O-Train, orders are always tailored to the buyer. However, in reality, this tailoring involves changes within certain parameters, such as train width, that differ greatly within Europe. Changes to parts that are uniform within Europe, such as the roofing, may lead to unforeseen complications. I don’t think the cost will be significant, but I can’t rule it out either, and I think the FRA should have been warier about this possibility.
The final worry is that the FRA states the cost of a high-speed train is $50 million, in the context of modification costs; these are stated to be $300,000 for a $50 million European high-speed trainset and $4.7 million for a Japanese one. The problem: European high-speed trainsets do not cost $50 million. They cost about $40 million. Japanese sets cost around $50 million, but that’s for a 16-car 400-meter trainsets, whereas European high-speed trainsets are almost always about 200 meters long, no matter how many cars they’re divided into. If the FRA is baking in cost premiums due to protectionism or bespoke orders, this is going to swamp the benefits of Euronorm-like regulations.
But cost concerns aside, the changes in the buff strength rules are an unmitigated good. The old rules require trainsets to resist 360-945 metric tons of force without deformation (360 for trains going up to 200 km/h, 945 beyond 200 km/h), which raises their mass by several tons per cars – and lightweight frames require even more extra mass. The new ones are based on crumple zones using a system called crash energy management (CEM), in which the train is allowed to deform as long as the deformation does not compromise the driver’s cab or the passenger-occupied interior, and this should not require extra train mass.
How does it affect procurement?
So far, the new rules, though telegraphed years in advance, have not affected procurement. With the exception of Caltrain, commuter railroads all over the country have kept ordering rolling stock compliant with the old rules. Even reformers have not paid much attention. In correspondence with Boston-area North-South Rail Link advocates I’ve had to keep insisting that schedules for an electrified MBTA must be done with modern single-level EMUs in mind rather than with Metro-North’s existing fleet, which weighs about 65 metric tons per car, more than 50% more than a FLIRT per unit of train length.
It’s too late for the LIRR to redo the M9, demanding it be as lightweight as it can be. However, New Jersey Transit’s MultiLevel III is still in the early stages, and the railroad should scrap everything and require alternate compliance in order to keep train mass (and procurement cost) under control.
Moreover, the MBTA needs new trains. If electrification happens, it will be because the existing fleet is so unreliable that it becomes attractive to buy a few EMUs to cover the Providence Line so that at least the worst-performing diesels can be retired. Under no circumstance should these trains be anything like Metro-North’s behemoths. The trains must be high-performance and as close as possible to unmodified 160 km/h single-level regional rail rolling stock, such as the DBAG Class 423, the Coradia Continental, the Talent II, or, yes, the FLIRT.
Metra is already finding itself in a bind. It enjoys its antediluvian gallery cars, splitting the difference between one and two decks in a way that combines the worst of both worlds; first-world manufacturers have moved on, and now Metra reportedly has difficulty finding anyone that will make new gallery cars. Instead, it too should aim at buying lightly modified European trains. These should be single-level and not bilevel, because bilevels take longer to unload, and Chicago’s CBD-dominant system is such that nearly all passengers would get off at one station, Millennium Station at the eastern edge of the Loop, where there are seven terminating tracks and (I believe) four approach tracks.
Ultimately, on electrified lines, the new rules permit trains that are around two thirds as heavy as the existing EMUs and have about the same power output. Substantial improvements in train speed are possible just from getting new equipment, even without taking into account procurement costs, maintenance costs, and electricity consumption. Despite its flaws, the new FRA regulation is positive for the industry and it’s imperative that passenger railroads adapt and buy better rolling stock.
To the transportation user, holidays are nothing but pain. Synchronized travel leads to traffic jams and very high rail and air fares, and synchronized shopping by car leads to parking pain. American commercial parking minimums are designed around the few busiest days of the year (source, endnote #8), timed for the Christmas rush. In France, synchronized travel at the beginning and end of school holidays is so bad that each region begins and ends its winter and spring breaks on different dates. There’s so much travel pain, and associated waste in designing transportation around it, that it’s worth asking why even bother.
The travel pain is even worse than mere congestion. When I visited London in early July, Eurostar broke in both directions. This was not a pair of random delays. French holiday travel is synchronized even though there are two months of summer break and only about one month of paid vacation net of the other holidays: traditionally people from all over the country and the world visit Paris in July, and then Parisians visit other places in August.
With slow boarding at the stations courtesy of security theater and manual ticket checks with just two access points per train, it takes longer than usual to board the trains when they are full. With full trains throughout the day, the delays cascaded, so by afternoon the trains were hours off schedule. Eurostar let passengers on trains on practically a first-come, first-served basis: people with tickets on a train got to ride the next available train. I had a ticket on an 11:39 train, and got to ride the train that was nominally the 11:13 (there were a few available seats) but departed at 12:58, and my nominally-11:39 train departed even later.
Eurostar’s inability to deal with crowds that occur annually, at a time when revenue is highest, is pure incompetence. But even if that particular problem is resolved, the more fundamental problem of unnecessary swings in travel volumes remains. On domestic TGVs it’s seen in wild price swings. Today is the 8th. In two weeks, a one-way TGV ticket from Paris to Marseille costs €72-74 on Thursday the 22nd or Friday the 23rd (Friday is the traditional peak weekend travel date and increasingly Thursday joins it) and about €62 on Saturday the 24th. But next month, on the 23rd, I see tickets for about €150, and even the low-comfort OuiGo option, which usually has €10 tickets (from the suburbs, not Paris proper), shoots up to €100; even with these prices, most trains are sold out already.
In some cultures, common holidays serve a religious or otherwise traditional purpose of bringing the extended family together. This is the case for Chinese New Year, which causes overcrowding on the mainline rail network at the beginning and end of the holiday as urban workers visit their families back home, often in faraway interior provinces. The same tradition of extended families occurs on Passover, but Israel has little travel pain, as it is so small that Seder travel is the same as any other afternoon rush hour.
However, there is no religious or social value to synchronized school holidays, nor is there such value to Western holidays. Western Christian civilization has centered nuclear families over extended families for around a millennium. In modern-day American culture, people seem to spend far more time complaining about the racist uncle than saying anything positive about catching up with relatives.
Christmas has religious significance, but much of the way it is celebrated in rich countries today is recent. The emphasis on shopping is not traditional, for one. The travel peak is probably unavoidable, since Christmas and New Year’s are at a perfect distance from each other for a week-long voyage, but everything else is avoidable. A source working for a bookstore in Florida, located strategically on the highway between Disneyland and the coast, told me of two prominent peaks. In the summer there would be a broad peak, consisting mostly of European tourists with their long paid vacations. But then there would be a much sharper peak for the holiday season between Thanksgiving and Christmas, in which the store would fill every cashier stall and pressure employees, many of whom temps working seasonally, to work overtime and get customers through as quickly as possible.
Some holidays have political significance, such as various national days, but those do not have to create travel peaks or shopping peaks. Bastille Day doesn’t.
Finally, while it’s accepted in Western countries today that summer is the nicest season to travel, this was not always the case, and even today there are some exceptions. The Riviera’s peak season used to be winter, as the English rich fled England’s dreary winters to the beaches; Promenade des Anglais in Nice is named after 19th century winter vacationers. When I lived in Stockholm, I was more excited to visit the Riviera in the winter, fleeing 3 pm sunsets, than in the summer. Today, Japan has a peak for the cherry blossom in the spring, while in New England (and again in Japan) there is a tradition of leaf peeping in the fall.
Instead of centering synchronized holidays, it’s better for states to spread travel as well as shopping behavior throughout the year as much as possible. Different people have different preferences for seasonality, and this is fine.
For bigger shopping seasons, the best thing to do is to emphasize birthdays. Instead of trying to fix major holidays, the way Lincoln did for Thanksgiving, it’s better to encourage people to make their biggest trips and biggest shopping around birthdays, anniversaries, saint days in Catholic countries, and idiosyncratic or subculturally significant days (such as conventions for various kinds of geeks). There are already well-placed traditions of birthday and anniversary gifts. In academia it’s also normal to extend conference trips into longer vacations, when they don’t conflict with teaching schedules.
The impact on labor is reduced seasonality, and far less peak stress. With less seasonal employment, the natural rate of unemployment may also end up slightly lower. The impact on transportation is a large reduction in travel peaks, which would make it easier to run consistent scheduled service year-round, and to maintain car travel and parking capacity at its average day level rather than building parking lots that go unused 364 days out of every year.
India’s economic development lags China’s by about 15 years, so it shouldn’t be surprising that it’s beginning to construct a high-speed rail network. The first line, connecting Mumbai and Ahmedabad via Surat, began construction at the end of last year, with completion targeted within four years; the two states served, Maharashtra and Gujarat, are more or less India’s two richest large states, and are also both deeply right-wing, with nearly every constituency backing Modi. There are some severe problems with the system, stemming from its use of turnkey Japanese technology. But more broadly, India’s geography is just difficult for high-speed rail, especially by comparison with other high-population density countries at similar level of development, like Pakistan and Indonesia.
The Mumbai-Ahmedabad corridor is to use imported Shinkansen technology, with Japanese financing. India has a vast railway network using broad gauge, with extensive regional rail (the Mumbai Suburban Railway has 2.6 billion riders per year) as well as legacy intercity rail.
However, to maintain Shinkansen compatibility, India has chosen to use standard gauge. This is based on a misunderstanding of why HSR uses standard gauge. Spain uses near-Indian gauge on its legacy network but standard gauge on HSR to maintain compatibility with the French TGV network, and Japan has narrow gauge on the legacy network and standard gauge on Shinkansen because narrow-gauge trains can’t run as fast. Neither of these justifications applies to India, and evidently, in another country where they don’t apply, Russia, HSR is to use broad gauge. With standard gauge, India will not be able to run HSR through to the legacy network, connecting to cities beyond the initial line, such as Delhi, nor will it be able to stage future construction to build lines in phases, the way France did, with through-service to lower-speed territory.
Even worse, alone in the world, India is using the Shinkansen’s loading gauge on HSR: trains are 3.35 meters wide, enough for 5-abreast seating. Indian Railways has a loading gauge allowing 3.66 meter trains, enough for 6-abreast seating with the same compromises on comfort familiar to every airline economy passenger. I don’t know what the standards for track centers are to be on India’s HSR: Indian Railways’ manual says 5.3 meters, which is wide enough for everything, but Shinkansen standards specify 4.3 meters, which is tight enough that a future widening of the track and loading gauges may pose difficulties for passing at high speed (at low speed it’s easy, India’s legacy track centers are 4.265 meters, and standard-gauge America’s are 3.7 meters on the slower parts of the Northeast Corridor).
During construction, the decision to use the wrong-size trains is fixable. Even after service opens, if the track centers are not too narrow, it’s possible to add a third rail to permit a transition to broad gauge. If the track centers are as narrow as the Shinkansen then might still be possible, if the third rails are on the outside (it would widen the track centers by the difference between the gauges, or 23.3 cm), but then the platforms would need to be shaved for wider trains. In the medium and long runs, such gauge widening is critical as India builds out its network.
But today, so complete is India’s reliance on Japanese technology that the training for drivers will be conducted in Japan, in Japanese; train drivers will be required to speak Japanese, as the Shinkansen trainers will not all speak English. It goes without saying that without a large body of Japanese speakers, India will be forced to pay first-world or near-first-world wages, forgoing its advantage in having low labor costs.
The projected construction cost of the 508-kilometer line is 1.1 trillion (“lakh crore”) rupees, which is $15 billion in exchange rate terms and about $55 billion in PPP terms. Per Wikipedia, the route includes only one tunnel, a 21-km approach to Mumbai with suburban and underwater tunneling (even if the gauges were compatible, using existing tracks like TGVs is impossible due to the use of every approach track by overcrowded Suburban Railway trains). The rest of the route is predominantly elevated, but the decision to runs the trains elevated rather than at-grade is only responsible for about 10% of its cost.
Despite the complexity of such a tunnel, there is no excuse for the high construction cost. In exchange rate terms it’s reasonable. Japan’s domestic Shin-Aomori extension of the Shinkansen cost about $55 million per kilometer, including a 26 km tunnel consisting of a third of the route and additional tunnels totaling a majority of the route. More recently, Japan’s new bout of Shinkansen construction costs about $30 billion for 389 km, but tunneling is extensive, with the Hokkaido route planned to be 76% in tunnel.
With India’s complete reliance on Japanese technology, paying the same as Japan in exchange rate terms is not surprising. It’s a disaster for India, which has to pay in depreciated rupees instead of leveraging its low-cost labor, but as far as Japan is concerned, it’s a perfect copy of the domestic Shinkansen system. Similar high costs can be observed for some Asian metro projects using Japanese financing, namely Dhaka (the world’s highest-cost elevated metro, even worse than in the US) and Jakarta.
In contrast, where India improves its rail network by tapping into Indian Railways’ own expertise, costs are low. Nearly half of India’s rail network is electrified, and to save money on expensive fuel, the country is rapidly electrifying the system, targeting 100% electrification. A plan to electrify 13,675 route-km in the next four years is to cost 12,134 crore rupees, about $123,000/km in exchange rate terms or $450,000/km in PPP terms. In the developed world, $1-1.5 million/km for electrification is reasonable, and the unreasonably expensive UK, US, and Canada go up to $5-10 million/km. Left to its own devices, Indian Railways can build things cheaply.
India’s geography for high-speed rail is not easy. Mumbai, Surat, and Ahmedabad are the only three cities in the top 20 that lie on a straight line at easy HSR range. Delhi-Mumbai, Delhi-Kolkata, and Mumbai-Chennai are all just outside the best range for HSR (and Kolkata-Chennai is well outside it), having to rely on intermediate cities like Ahmedabad, Hyderabad, and Kanpur for ridership. Within Uttar Pradesh, Kanpur and Lucknow are both large cities, but the line connecting them is almost perpendicular to that connecting Delhi and Kolkata, so that only one can be served on the main line. In the South, there is a similar situation with Mumbai-Chennai, via either Bangalore or Hyderabad (and there, both routes should be built as Bangalore and Hyderabad are both near-megacities). Mumbai itself requires extensive tunneling in all directions: north toward Gujarat and Delhi, south toward Pune, and possibly also northeast toward the interior cities of Maharashtra.
I drew a possible map for a nationwide network. The total length is 17,700 double-track-km. It’s about the same length as most American proposals, and less than half as much as what China aims to build by 2025, but India has four times the population of the US and far higher population density, and its density is also several times that of China. For a better comparison, consider Pakistan: it is slightly less dense than India and has about 15% India’s population, and yet two spines totaling about 1,800 km, Karachi-Lahore and Lahore-Islamabad-Peshawar, would connect nearly every major city. Lying on the Indus, much of Pakistan has a linear population distribution, facilitating rail connections.
With a difficult urban geography for HSR, India has to take especial care to reduce construction costs. This means, in turn, that it needs to rely on indigenous expertise and standards whenever possible. When imported technology is unavoidable, it needs to provide its own financing (with an annual budget of 29 trillion rupees, it can afford to do so) and force Japanese, Korean, and European vendors to compete. A Chinese-style tech transfer (read: theft) is not possible – the vendors got burned once and won’t agree to the same again – but domestic driver training, with the foreign role restricted to the rolling stock (built to Indian standards) and engineering, is essential and unlikely to bother the global industry.
Following up on my last post’s promise to tackle both cultural theory of risk and cultural cringe, here is my take on the latter issue.
It is normal for people to have some degree of national pride and fervor. Cultural cringe refers to the opposite trend: when, in some circumstances, people in certain countries feel national shame and develop an inferiority complex. The term cultural cringe itself was coined by A. A. Phillips in 1950, describing Australia’s inferiority complex toward Britain in literary fields: Australians thought their literature was too provincial and perhaps too incomprehensible to the British readers, and as a result many authors were uncomfortable making the local references celebrated in the literary canon of Britain, France, Russia, the US, etc. This notion has been generalized elsewhere. Amos Oz says he felt uncomfortable writing books in such a peripheral country as Israel until he read Sherwood Anderson’s Winesburg, Ohio, showing how literature of and by the provinces can thrive.
From its origin in Australian literature, the idea of the cultural cringe has expanded to other fields, including the law, social relations, technology, and business. It seems endemic in former colonies, especially ones that are not rich. One writer in Nigeria argues how best practices thinking is cultural cringe by giving an example of a recent legal importation that turns out to already exist in traditional Yoruba law. In Australia itself, political scientist L. J. Hume pushed back against the notion that there is cultural cringe, arguing it is true of literature but not economics of other fields. But in mass culture, the vast majority of countries, both developed and developing, consider American film and television superior to their own and have domestic industries that focus on arthouse films or low-budget flicks.
Cultural cringe in legal, political, or technological fields remains endemic in many other developed countries. In one recent example, Emmanuel Macron said France is inherently resistant to change and (by implication) ungovernable, comparing it negatively with Denmark. In business, 1980s-era America was replete with books telling managers how to think like a Japanese or German, which trend ended when the Japanese lost decade and the economic crisis of German unification made these countries less fashionable.
Lying in the intersection of business, politics, and technology, urbanism and transportation are amenable to analysis using this concept. As in the Nigerian example, the third world tends to have too much cultural cringe and too much faith in the merits of importing first-world methods. Conversely, the United States (and to a large extent Canada) today is resistant to outside ideas and does not know how to be a periphery.
Urban layout: there’s a world outside Europe
During the SB 827 debate in California, supporters reassured restive city residents that the density the bill promoted – up to 7 floors right next to transit lines and up to 5 a little farther away – was gentle. “Paris density,” they said. Everyone likes Paris as a tourist. Everyone recognizes Paris as good urbanism.
There is very little cultural cringe in the United States – on the contrary, Americans are solipsistic in every field. However, one of very few exceptions is that the American middle class vacations in Europe and is familiar with how walkable European cities are. (It’s even referenced on Mad Men when a minor character goes on walks in their car-oriented New York suburb.) Paris is the largest and richest city Americans of a certain wealth and education level can be expected to be familiar with and like, but by the same token the YIMBYs could mention Barcelona, Amsterdam, and Rome.
But it’s useful to think of what was not mentioned. Certainly not Hong Kong or Dubai, which seem to be mentioned almost exclusively negatively in Western discourse. Not Tokyo, which Westerners are much less likely to visit to the point that the Western blogs talking about Japanese urbanism (like Urban Kchoze) are notable for it. Nothing in the middle-income world, including some old cities (like Mexico City and Istanbul) that have building height, street width, and stylistic variation that first-world urbanists would approve of (and do if they’ve been there).
In this situation, the invocation of famous European cities feels less like a dialogue and more like an attempt to induce cringe defensively, to make people feel less attached to their cities’ American auto-oriented character. In effect, it’s an attack on “it will change the character of our neighborhood,” a line that’s much less common in countries that are used to thinking of themselves as inferior to whatever they consider the metropolitan core (such as the first world writ large in Israel, or the former colonial master in ex-colonies).
Transportation: a little cringe is good, but not too much
In the developing world, there is extensive cringe. Without using that term, I suggested it as a reason behind high construction costs in the third world, which are similar to the costs of the first world today and several times as high as those of the first world from back when its income levels were comparable to those of subway-building third-world countries, in the early 1900s. In Latin America and China, development is more inward-looking, and China in particular learned to build subways from the USSR in the 1950s, not a rich country. In former colonies, there seems to be a greater willingness to import methods from either the former colonizer or from countries that aggressively invest in third-world infrastructure, like Japan and China; the result is very high construction costs for projects for which I have data in India and other countries of that development level.
In some cases, like India’s high-speed rail program, the country imports technology wholesale, and Japan (or China) may insist on an exact copy of its methods. As it is, Japan refuses to call Taiwan High-Speed Rail a Shinkansen system even though it runs Shinkansen rolling stock: construction methods were European, so Japan only calls THSR a high-speed rail system using Shinkansen-based technology.
However, decisions like India’s standard-gauge metro lines happen even in indigenous systems. Delhi Metro uses standard gauge not for some turnkey technological import, but purely because it feels more modern whereas Indian mainline trains feel dinghy and dangerous. Evidently, Delhi Metro electrification is 25 kV, which is standard on mainline trains but unheard of on first-world metros; modifying subways for high-voltage electrification requires expensive concrete pouring, since high-voltage catenary requires more generous clearances to avoid arcing, whereas modifying rail gauge is routine since the European vendors are used to selling to broad-gauge Finland and Spain and the Japanese ones are used to their country’s multitude of gauges.
And if India errs on the side of too much shiny adoption of foreign technology, the US errs on the side of adopting too little. Americans do not think their country is inferior. American authors do not think they need to experience another country or speak another language before they write. There was a time when the American business community felt outcompeted, but today it feels like it’s at the top of the world, Silicon Valley having long left Japanese corporations in the dust; I stopped seeing complaints that American cars were inferior to German and Japanese ones not long after Obama’s auto industry bailout.
The American policy sphere seems especially constrained. There is some cultural cringe toward London, leading thinktanks like the Regional Plan Association and TransitCenter to overlearn from London’s peculiarities (like the Oyster fare cap and contactless credit card payment), but not much toward Continental Europe and practically none toward Japan. Instead, the attitude toward non-English-speaking countries is one of dismissal. When Richard Mlynarik pointed out to a Caltrain official that Japanese trains turned much faster at terminals than Caltrain thought possible, the official replied, “Asians don’t value life the way we do.”
If India fails to understand where its own methods could be superior despite being a peripheral country, the United States fails to understand that it’s a peripheral country in the first place. Transportation innovation rarely happens in North America. It happens in Western Europe and Japan, and to some extent in developing countries that have less cultural cringe than former colonies, such as Brazil and Colombia and their invention of BRT or Colombia, Bolivia, and Mexico’s use of aerial gondolas in mountainous suburban areas.
Urban development: you are not New York
I’ve been reading Aaron Renn’s blog, the Urbanophile, since maybe 2008. At the time he was still in Indianapolis, in (I believe) management consulting, writing about how his city was trying to become culturally and economically bigger than it was, and sometimes but not always succeeding. A recurrent theme in his writings has been that Midwestern American cities are desperate for development. They keep saying they need more creative people, more venture capital, or whatever else is in vogue. (In contrast, he says, Rhode Island, where he lived later, doesn’t even understand how peripheral it is.)
However, the way the Midwestern cities he focuses on try to attract this elusive development is through cheap copying. An old post of his I can no longer find contrasts world-class Indianapolis with world class in Indianapolis. The former involves investing in some city institution to make it world-class, or more realistically notable enough that boosters can call it world-class with a straight face. The latter involves inviting a starchitect or another person with international cachet (such as Richard Florida) to build something in Indianapolis that’s notable and is exactly as notable as what this person might build in any other city of that size, with no particular connection to the city itself.
In the transportation field, many American cities build mixed-traffic downtown streetcars and beam with pride if they get 4,000 riders per weekday. Often this mentality overrides any attempt to provide services to city residents: thus, the streetcar in Detroit is not integrated with the city’s bus network, and in fact a bus runs on the same street, on different lanes from the streetcar. This isn’t about some mythical preference for rail over bus: these cities build whatever they hear is in vogue and will get them noticed by New York media, whether it’s peak-only commuter rail, a downtown streetcar, a limited bus that calls itself BRT, or now a bus network redesign around untimed 15-minute frequencies.
Cringe vs. dialogue
It’s important to distinguish dialogue with a foreign culture and cultural cringe toward it. One difference is that cringe implies infatuation; however, infatuation can also develop among immigrants who are steeped in the metropole’s culture after having lived there even while maintaining ties to the old country. A bigger difference is the extent of two-way dialogue. Israelis use the expression “unbroken country” to refer to the mythical average first-world country in which you can get things done without having to tell government bureaucrats that you served in the military with their bosses; however, few have lived abroad long enough to know the details of what makes these countries tick better.
With limited knowledge of the core, the periphery can worship at the feet of the few people who do know, which leads to political bias. This is where moral panics of no-go zones come from: there is an Israeli television show purporting to portray how things are in Europe, but any connection between Belleville (or other racially diverse Paris neighborhoods) and what they depict is completely incidental. In that case, the bias is right-wing. In the opposite direction, left-wing bias can occur when American liberals and socialists are enamored by European health care and education systems and elide a thousand details that distinguish them from American renditions of single-payer health care or free college tuition.
But the biased reaction is only common in places that care little about how to govern. “Well, actually Tower Hamlets is a no-go zone” is not a blueprint for reducing nonwhite immigration to the United States or Israel. Instead, in the policy sphere a more common reaction is a shrug. Dialogue is threatening: the people capable of it are typically not the top pundits on this issue. Instead, it’s more common to aggressively dismiss knowledge that’s hard to access, even among people who at the same time invoke the cringe. In Israel it takes the form of self-denigrating lines like “this is Israel, not Finland.” Cultural cringe leads to lower expectations this way.
When Phillips criticized Australian authors who deracinated their writing to appeal to British taste, he was implicitly saying that Australians couldn’t root their literature in British experience. Oz, similarly, felt constrained about writing when he was young because living in Israel, he could not root his books in Paris, Milan, and other flashy cities whose books he devoured. The economic (or legal, or technological) analogue of this observation is that the reason there is cultural cringe is that people in peripheral areas (which in transportation include the United States) are too unfamiliar with the core and cannot dialogue with it the way people in different parts of the core can.
Urbanism is not literature. One doesn’t need extraordinary sensitivity and a lifetime (short as it may be) in a culture to produce very good insights about transportation, housing, or municipal governance. It’s possible to break out of the cringe by acquiring detailed knowledge of how the core operates. In the case of the third world and subway construction, it means learning enough about current and historical construction methods to be able to propose ways to build infrastructure at low costs commensurate with these cities’ low wages; in the case of the United States, it means learning enough about what makes European, Japanese, Latin American, etc. urbanism tick that it can be adopted domestically.
Urbanism is not literature in a far more important sense: there really are better and worse traditions there. It’s not enough to have pride in what you have when what you have is a third-world city where the poor don’t have running water, or for that matter an American city that would shut down instantly were gas prices to rise to levels necessary to stop global warming. Learning from the core is crucial. It’s just equally important to do so through dialogue and not through the ignorant self-denigration that is cultural cringe.
I ran a Patreon poll with three options for posts about design compromises: overbuilding for future capacity needs, building around compromises with unfixably bad operations, and where to build when it’s impossible to get transit-oriented development right. Overbuilding won with 16 votes to bad operations’ 10 and development’s 13.
It’s generally best to build infrastructure based exactly on expected use. Too little and it gets clogged, too much and the cost of construction is wasted. This means that when it comes to rail construction, especially mainline rail, infrastructure should be sized for the schedule the railroad intends to run in the coming years. The Swiss principle that the schedule comes first was just adopted in Germany; based on this principle, infrastructure construction is geared around making timed transfers and overtakes and shortening schedules to be an integer (or half-integer) multiple of the headway minus turnaround time for maximum equipment utilization.
And yet, things aren’t always this neat. This post’s topic is the issue of diachronic optimization. If I design the perfect rail network for services that come every 30 minutes, I will probably end up with a massive upgrade bill if ridership increases to the point of requiring a train every 20 minutes instead. (I chose these two illustrative numbers specifically because 30 is not a multiple of 20.) In some cases, it’s defensible to just build for higher capacity – full double-tracking even if current ridership only warrants a single track with passing sidings, train stations with more tracks in case more lines are built to connect to them, and so on. It’s a common enough situation that it’s worth discussing when what is technically overbuilding is desirable.
Expected growth rates
A fast-growing area can expect future rail traffic to rise, which implies that building for future capacity today is good. However, there are two important caveats. The first is that higher growth usually also means higher uncertainty: maybe our two-track commuter line designed around a peak of 8 trains per hour in each direction will need 32 trains per hour, or maybe it will stay at 8 for generations on end – we usually can’t guarantee it will rise steadily to 16.
The second caveat, applicable to fast-growing developing countries, is that high growth raises the cost of capital. Early British railroads were built to higher standard than American ones, and the explanation I’ve seen in the rail history literature is that the US had a much higher cost of capital (since growth rates were high and land was free). Thus mainlines in cities (like the Harlem) ran in the middle of the street in the US but on elevated structures in Britain.
But with that in mind, construction costs have a secular increase. Moreover, in constrained urban areas, the dominant cost of above-ground infrastructure cost is finding land for multiple tracks of railroad (or lanes of highway), and those are definitely trending up. The English working class spent 4-5% of its income on rent around 1800 (source, PDF-p. 12); today, spending one third of income on rent is more typical, implying housing costs have grown faster than incomes, let alone the general price index.
The upshot is that cities that can realistically expect large increases in population should overbuild more, and optimize the network around a specific level of traffic less. Switzerland and Germany, both of which are mature, low-population growth economies, can realistically predict traffic many decades hence. India, not so much.
The expected growth rate helps determine the future benefits of overbuilding now, including reduced overall costs from fronting construction when costs are expected to grow. Against these benefits, we must evaluate the costs of building more than necessary. These are highly idiosyncratic, and depend on precise locations of needed meets and overtakes, potential connection points, and the range of likely train frequencies.
On the Providence Line, the infrastructure today is good for an intercity train at current Amtrak speed every 15 minutes and a regional train making every stop every 15 minutes. There is one overtake segment at Attleboro, around three quarters of the way from Boston to Providence, and the line is otherwise double-track with only one flat junction, with the Stoughton branch. If intercity trains are sped up to the maximum speed permitted by right-of-way geometry, an additional overtake segment is required about a quarter of the way through, around Readville and Route 128. If the trains come every 10 minutes, in theory a mid-line overtake in Sharon is required, but in practice three overtakes would be so fragile that instead most of the line would need to be four-tracked (probably the entire segment from Sharon to Attleboro at least). This raises the incremental costs of providing infrastructure for 10-minute service – and conversely, all of this is in lightly developed areas, so it can be deferred without excessive future increase in costs.
An even starker example of high incremental costs is in London. Crossrail 2 consists of three pieces: the central tunnel between Clapham Junction and Euston-St. Pancras, the northern tunnel meandering east to the Lea Valley Lines and then back west to connect to the East Coast Main Line, and the southern tunnel providing two extra tracks alongside the four-track South West Main Line. The SWML is held to be at capacity, but it’s not actually at the capacity of an RER or S-Bahn system (as I understand it, it runs 32 trains per hour at the peak); the two extra tracks come from an expectation of future growth. However, the extreme cost of an urban tunnel with multiple new stations, even in relatively suburban South London, is such that the tunnel has to be deferred in favor of above-ground treatments until it becomes absolutely necessary.
In contrast, an example of low incremental costs is putting four tracks in a cut-and-cover subway tunnel. In absolute terms it’s more expensive than adding passing tracks in suburban Massachusetts, but the effect on capacity is much bigger (it’s an entire track pair, supporting a train every 2 minutes), and moreover, rebuilding a two-track tunnel to have four tracks in the future is expensive. Philadelphia most likely made the right choice to build the Broad Street Line four-track even though its ridership is far below the capacity of two – in the 1920s it seemed like ridership would keep growing. In developing countries building elevated or cut-and-cover metros, the same logic applies.
The two main aspects of every infrastructure decision are costs and benefits. But we can discern some patterns in when overbuilding is useful:
- Closing a pinch point in a network, such as a single- or double-track pinch point or a flat junction, is usually worth it.
- Cut-and-cover or elevated metro lines in cities that are as large as prewar New York (which had 7 million people plus maybe 2 million in the suburbs) or can expect to grow to that size class should have four tracks.
- On a piece of infrastructure that is likely to be profitable, like high-speed rail, deferring capacity increases until after operations start can be prudent, since the need to start up the profitable system quickly increase the cost of capital.
- Realistic future projections are imperative. Your mature first-world city is not going to triple its travel demand in the foreseeable future.
- Higher uncertainty raises the effective cost of capital, but it also makes precise planning to a specific schedule more difficult, which means that overbuilding to allow for more service options becomes reasonable.
- The electronics before concrete principle extends to overbuilding: it’s better to complete a system (such as ETCS signaling or electrification) even if some branches don’t merit it yet just because of the benefits of having a single streamlined class of service, and because of the relatively low cost of electronics.
Usually cities and countries should not try to build infrastructure ahead of demand – there are other public and private priorities competing for the same pool of money. But there are some exceptions, and I believe these principles can help agencies decide. As a matter of practice, I don’t think there are a lot of places in the developed world where I’d prescribe overbuilding, but in the developing world it’s more common due to higher future growth rates.