Category: Transportation
Quick Note: RER and S-Bahn Line Length
An email correspondent asks me about whether cities should build subway or commuter rail lines, and Adirondacker in comments frequently compares the express lines in New York to the RER. So to showcase the difference, here are some lines with their lengths. The length is measured one-tailed, from a chosen central point.
| Line | Central point | Length (km) |
| RER A to MLV | Les Halles | 37 |
| RER A to Cergy | Les Halles | 40.5 |
| RER B to CDG | Les Halles | 31 |
| RER B to Saint-Rémy | Les Halles | 32.5 |
| RER D to Malesherbes | Les Halles | 79 |
| Crossrail to Shenfield | Farringdon | 34 |
| Crossrail to Reading | Farringdon | 62.5 |
| Thameslink to Brighton | Farringdon | 81 |
| Thameslink to Bedford | Farringdon | 82 |
Express subway lines in New York never go that far; the A train, the longest in the system, is 50 km two-tailed, and not much more than 30 km one-tailed to Far Rockaway. The Berlin S-Bahn is about comparable, in a metro area one quarter the size.
The Danbury Branch and Rail Modernization
I’ve been asked to talk about how rail modernization programs, like the high-speed rail plan we published at Marron this month, affect the Danbury Branch of the New Haven Line. The proposal barely talks about branch modernization beyond saying that the branches should be electrified; we didn’t have time to write precise branch timetables, which means that the timetable I’m going to post here is going to have more rounding artifacts. The good news is that modernization can be done cheaply, piggybacking on required work on the main of the New Haven Line.
Current conditions
The Danbury Branch is a 38 km single-track unelectrified line, connecting South Norwalk with Danbury making six additional intermediate stops. All stations have high platforms, but they are short, ranging between three and six cars.
Ridership is essentially unidirectional: toward Norwalk and New York in the morning, back north in the afternoon. There is little job concentration near the stations. Within 1 km of Danbury there are only 5,000 jobs per OnTheMap, rising to 10,000 if we include Danbury Hospital, which is barely outside the station’s 1 km radius (but is not easily walkable from it). Merritt 7 is in an office park, but there are only 6,000 jobs there, and nearly everyone drives. The other stations are parking lots, and Bethel is somewhat outside the town center for better parking.
The right-of-way is very curvy, much more so than the main line. Where most of the New Haven Line is built to a standard of 2° curves (radius 873 m), permitting 157 km/h with modern cant and cant deficiency, the Danbury Branch scarcely has a section straight enough with gentler curves than 3°, and much of it has such frequent 4° curves that trains cannot go faster than 100 km/h except for speedups of a few seconds at a time to recover delays.
A first pass on infrastructure and operations
It is effectively free to electrify a 38 km single-track line. The high-speed rail report estimates it at $75 million based on both European electrification costs (see report for sources) and the Southern Transcon proposal, which is $2 million/km on a busy double-track line. The junction between the branch and the main line is flat, but outbound trains can be timetabled to avoid conflict, and inbound trains have no at-grade conflict to begin with. If platform lengthening is desired, then it is a noticeable extra expense; figure $30 million for each eight-car platform, or perhaps half that on single track (but then some stops are double-track), maybe with some pro-rating for existing platforms if they can be easily reused.
The tracks should also be maintained to higher speed, which is a routine application of a track laying machine, with some weekend closures for construction followed by what should be an uninterrupted multidecade period of operations. The curves are already superelevated to a maximum of 5-6″; this is less than the 7″ maximum in US law (180 mm here), but the difference is not massive. The line has a 50 mph speed limit today for the most part, whereas it can be boosted to about 100-110 km/h depending on section, a smaller difference than taking the main line’s 70 mph and turning it into 150-160 km/h.
With a blanket speed limit of 110 km/h – in truth some sections need to dip down to 100 or even less whereas the Bethel-Danbury and Merritt 7-Wilton interstations can be done mostly at 130 – the trip time between South Norwalk and Danbury is, inclusive of 7% pad, 28.75 minutes. The Northeast Corridor report timetables have express New Haven Line commuter trains arriving South Norwalk southbound at :15.25 every 20 minutes and departing northbound at :14.75, so they’d be departing Danbury at :46.5 and arriving :43.5. Meets would occur at the :20, :30, and :40 points.
The :30 point, important as it is a meet even if service is reduced to every 30 minutes, is just south of Branchville, likely too far to use the existing meet at the station. Thus, at first pass, some additional double-tracking is needed, a total of 6 km if it covers the entire Cannondale-Branchville interstation, which would cost around $50 million at MBTA Franklin Line costs. MBTA Franklin Line costs are likely an underestimate, since the terrain on the Cannondale-Branchville interstation is hillier and some additional earthworks would be required on part of the section. A high-end estimate should be the cost of a high-speed rail line without elevated or tunneled segments, around $30 million/km or even less (cut-and-fill isn’t needed as much when the line curves with the topography), say $150 million.
The :20 point southbound is at or just south of Bethel. While this is in a built-up area, the right-of-way looks wide enough for two tracks and the topography is easier; if the station is the meet, then the cost is effectively zero, bundled into a platform lengthening project. Potentially, this could even be further bundled with moving the station slightly south to be closer to the town center. The :40 point southbound is at Merritt 7, which has room for a second track but not necessarily for a platform at it, and could instead get a second track on the opposite side of the platform if there’s enough of a rebuild to turn it into an island with additional vertical circulation; the cost of the second track itself would be a rounding error but the cost of station reconstruction would not be and would likely be in the mid-tens of millions.
How this fits into the broader system
The timetable in the report already assumes that New Haven Line service comprises 6 peak trains per hour (tph) that use the branches. The default assumption, reproduced in the service network graphic, is that New Canaan and Danbury get 3 tph each, and New Canaan gets a grade-separated junction but Danbury does not. Those trains all go to Grand Central with no through-running: only the local trains on the New Haven Line get to run through, since local trains are the highest priority for through-running. If a tunnel connecting the Gateway tunnel with Grand Central is opened, as in some long-term plans (here’s ETA’s, which isn’t very different from past blog posts’), then they can run through to it.
The establishment of this service is not going to, by itself, change the characteristic of ridership on the line. Electrification, better timetabling, and better rolling stock (in this order) can reduce the trip time from an hour today to 29 minutes, and the trip time to Grand Central from about 2:25 to 1:09, but the main effect would be to greatly improve the connectivity of existing users, who’d be driving to the parking lot stations more often, perhaps working from the office more and from home less, or taking the train to social events in the city. Some would opt to use the train to get to work at Stamford, as a secondary market. Over time, I expect that people would buy in the area to commute to work in New York (or at Stamford), but housing permit rates in Fairfield County are low and only limited TOD is likely. It would take concerted commercial TOD at the stations to produce reverse-peak ridership, likely starting with expanding the Merritt 7 office park and making it a bit less auto-oriented.
If the ridership isn’t there, then a train every 20 minutes is not warranted and only a train every 30 minutes should be provided. This reduces the double-track infrastructure requirement but only marginally, as the meets that are no longer needed are the easy ones and the one that still is is the hard one to build, south of Branchville. In effect, something like 80% of the cost provides two thirds of the capacity; this is common to rail projects, in that small cuts in an already optimized budget lead to much larger cuts in benefits, the opposite of what one hopes to achieve when optimizing cuts.
The Northeast Corridor Report is Out
Here is the link. If people have questions, please post them in comments and I’ll address; see also Bluesky thread (and Mastodon but there are no questions there yet).
Especial thanks go to everyone who helped with it – most of all Devin Wilkins for the tools, analysis, and coding work that produced the timetables, which, as the scheduling section says, are the final product as perceived by the passenger. Other than Devin, the other members of the TCP/TLU program at Marron gave invaluable feedback, and Elif has done extensive work with both typesetting and managing the still under-construction graphical narrative we’re about to do (expected delivery: mid-June). Members of ETA have looked over as well, and Madison and Khyber nitpicked the overhead electrification section in infrastructure investment until it was good. And finally, Cid was always helpful, whether with personal support, or with looking over the overview as a layperson.
Against State of Good Repair
We’re releasing our high-speed rail report later this week. It’s a technical report rather than a historical or institutional one, so I’d like to talk about a point that is mentioned in the introduction explaining why we think it’s possible to build high-speed rail on the Northeast Corridor for $17 billion: the current investment program, Connect 2037, centers renewal and maintenance more than expansion, under the moniker State of Good Repair (SOGR). In essence, megaprojects have a set of well-understood problems of high costs and deficient outcomes, behind-the-scenes maintenance has a different set of problems, and SOGR combines the worst of both worlds and the benefits of neither. I’ve talked about this before in other contexts – about Connecticut rail renewal costs, or leakage in megaproject budgeting, or the history of SOGR on the New York City Subway, or Northeast Corridor catenary. Here I’d like to synthesize this into a single critique.
What is SOGR?
SOGR is a long-term capital investment to bring all capital assets into their expected lifespan and maintenance status. If a piece of equipment is supposed to be replaced every 40 years and is currently over 40, it’s not in good repair. If the mean distance between failures falls below a certain prescribed level, it’s not in good repair. If maintenance intervals grow beyond prescription, then the asset to be maintained is not in good repair. In practice, the lifespans are somewhat conservative so in practice a lot of things fall out of good repair and the system keeps running. The upshot is that because the maintenance standards are somewhat flexible, it’s easy to defer maintenance to make the system look financially healthier, or to deal with an unexpected budget shortfall.
Modern American SOGR goes back to the New York subway renewal programs of the 1980s and 90s, which worked well. The problem is that, just as the success of one infrastructure expansion tempts the construction of other, less socially profitable ones, the success of SOGR tempted agencies to justify large capital expenses on SOGR grounds. In effect, what should have been a one-time program to recover from the 1970s was generalized as a way of doing maintenance and renewal to react to the availability of money.
Megaprojects and non-megaprojects
In practice, what defines a megaproject is relative – a 6 km light rail extension is a megaproject in Boston but not in Paris – and this also means that they are not easy to locally benchmark, or else there would be many like them and they would be more routine. This means that megaprojects are, by definition, unusual. Their outcome is visible, and this attracts high-profile politicians and civil servants looking to make their mark. Conversely, their budgeting is less visible, because what must be included is not always clear. This leads to problems of bloat (this is the leakage problem), politicization, surplus extraction, and plain lying by proponents.
Non-megaprojects have, in effect, the opposite set of problems. Their individual components can be benchmarked easily, because they happen routinely. A short Paris Métro extension, a few new infill stations, and a weekend service change for track renewal in New York are all examples of non-megaprojects. These are done at the purely professional level, and if politicians or top managers intervene, it’s usually at the most general level, for example the institution of Fastrack as a general way of doing subway maintenance, and that too can be benchmarked internally. In this case, none of the usual problems of megaprojects is likely. Instead, problems occur because, while the budgeting can be visible to the agency, the project itself is not visible to the general public. If an entire new subway line’s construction fails and the line does not open, this is publicly visible, to the embarrassment of the politicians and agency heads who intended to take credit for it. In contrast, if a weekend service change has lower productivity than usual, the public won’t know until this problem has metastasized in general, by which point the agency has probably lost the ability to do this efficiently.
And to be clear, just as megaprojects like new subway lines vary widely in their ability to build efficiently, so do non-megaproject capital investments vary, if anything even more. The example I gave writing about Connecticut’s ill-conceived SOGR program, repeated in the high-speed rail report, is that per track- or route-km the state spends in one year about 60% as much as what Germany spends on a once per generation renewal program, to be undertaken about every 35 years. Annually, the difference is a factor of about 20. New York subway maintenance has degraded internally over time, due to ever tighter flagging rules, designed for worker protection, except that worker injuries rose from 1999 to the 2010s.
The Transit Costs Project
The goal of the Transit Costs Project is to use international benchmarking to allow cities to benefit from the best of both worlds. Megaprojects benefit from public visibility and from the inherent embarrassment to a politician or even a city or state that can’t build them: “New York can’t expand the subway” is a common mockery in American good-government spaces, and people in Germany mock both Bavaria for the high costs and long timeline of the second Munich S-Bahn tunnel and Berlin for, while its costs are rather normal, not building anything, not even the much-promised tram alternatives to the U-Bahn. Conversely, politicians do get political capital from the successful completion of a megaproject, encouraging their construction, even when not socially profitable.
Where we come in is using global benchmarking to remove the question marks from such projects. A subway extension may be a once in a generation effort in an American city, but globally it is not, and therefore, we look into how as much of the entire world as we can see into does this, to establish norms. This includes station designs to avoid overbuilding, project delivery and procurement strategies, system standards, and other aspects. Not even New York is as special as it thinks it is.
To some extent, this combination of the best features of both megaprojects and non-megaprojects exists in cities with low construction costs. This is not as tautological as it sounds. Rather, I claim that when construction costs are low, even visible extensions to the system fall below the threshold of a megaproject, and thus incremental metro extensions are built by professionals, with more public visibility providing a layer of transparency than for a renewal project. This way, growth can sustain itself until the city runs out of good places to build or until an economic crisis like the Great Recession in Spain makes nearly all capital work stop. In this environment, politicians grow to trust that if they want something big built, they can just give more money to more of the same, serving many neighborhoods at once.
In places with higher costs, or in places that are small enough that even with low costs it’s rare to build new metro lines, this is not available. This requires the global benchmarking that we use; occasionally, national benchmarking could work, in a country with medium costs and low willingness to build (for example, Germany), but this isn’t common.
The SOGR problem
If what we aim to do with the Transit Costs Project is to combine the positive features of megaprojects and non-megaprojects, SOGR does the exact opposite. It is conceived as a single large program, acting as the centerpiece of a capital plan that can go into the tens of billions of dollars, and is therefore a megaproject. But then there’s no visible, actionable, tangible promise there. There is no concrete promise of higher speed or capacity. To the extent some programs do have such a promise, they are subsumed into something much bigger, which means that failing to meet standards on (say) elevator reliability can be excused if other things are said to go into a state of good repair, whatever that means to the general public.
Thus, SOGR invites levels of bloat going well beyond those of normal expansion megaprojects. Any project can be added to the SOGR list, with little oversight – it isn’t and can’t be locally benchmarked so there is no mid-career professional who can push back, and conversely it isn’t so visible to the general public that a general manager or politician can push back demanding a fixed opening deadline. For the same reason, inefficiency can fester, because nobody at either the middle or upper level has the clear ability to demand better.
Worse, once the mentality of SOGR is accepted, more capital projects, on either the renewal side or the expansion side, are tied to it, reducing their efficiency. For example, the catenary on the Northeast Corridor south of New York requires an upgrade from fixed termination/variable tension to auto-tension/constant tension. But Amtrak has undermaintained the catenary expecting money for upgrades any decade now, and now Amtrak claims that the entire system must be replaced, not just the catenary but also the poles and substations. The language used, “the system is falling apart” and “the system is maintained with duct tape,” invites urgency, and not the question, “if you didn’t maintain this all this time, why should we trust you on anything?”. With the skepticism of the latter question, we can see that the substations are a separate issue from the catenary, and ask whether the poles can be rebuilt in place to reduce disruption, to which the vendors I’ve spoken with suggested the answer is yes using bracing.
The Connecticut track renewal program falls into the same trap. With no tangible promise of better service, the state’s rail lines are under constant closures for maintenance, which is done at exceptionally low productivity – manually usually, and when they finally obtained a track laying machine recently they’ve used it at one tenth its expected productivity. Once this is accepted as the normal way of doing things, when someone from the outside suggests they could do better, like Ned Lamont with his 30-30-30 proposal, the response is to make up excuses why it’s not possible. Why disturb the racket?
The way forward
The only way forward is to completely eliminate SOGR from one’s lexicon. Big capital programs must exclusively fund expansion, and project managers must learn to look with suspicion on any attempt to let maintenance projects piggyback on them.
Instead, maintenance and renewal should be budgeted separately from each other and separately from expansion. Maintenance should be budgeted on the same ongoing basis as operations. If it’s too expensive, this is evidence that it’s not efficient enough and should be mechanized better; on a modern railroad in a developed country, there is no need to have maintenance of way workers walk the tracks instead of riding a track inspection train or a track laying machine. With mechanized maintenance, inventory management is also simplified, in the sense that an entire section of track has consistent maintenance history, rather than each sleeper having been installed in a different year replacing a defective one.
Renewal can be funded on a one-time basis since the exact interval can be fudged somewhat and the works can be timed based on other work or even a recession requiring economic stimulus. But this must be held separate from expansion, again to avoid the Connecticut problem of putting the entire rail network under constant maintenance because slow zones are accepted as a fact of life.
The importance of splitting these off is that it makes it easier to say “no” to bad expansion projects masquerading as urgent maintenance. No, it’s not urgent to replace a bridge if the cost of doing so is $1 billion to cross a 100 meter wide river. No, the substations are a separate system from the overhead catenary and you shouldn’t bundle them into one project.
With SOGR stripped off, it’s possible to achieve the Transit Costs Project goal of combining the best rather than the worst features of megaprojects and non-megaprojects. High-speed rail is visible and has long been a common ask on the Northeast Corridor, and with the components split off, it’s possible to look into each and benchmark to what it should include and how it should be built. Just as New York is not special when it comes to subways, the United States is not special when it comes to intercity rail, it just lags in planning coordination and technology. With everything done transparently based on best practices, it is indeed possible to build this on an expansion budget of about $17 billion and a rounding-error track laying machine budget.
The Problems of not Killing Penn Expansion and of Tariffs
Penn Station Expansion is a useless project. This is not news; the idea was suspicious from the start, and since then we’ve done layers of simulation, most recently of train-platform-mezzanine passenger flow. However, what is news is that the Trump administration is aiming to take over Penn Reconstruction (a separate, also bad project) from the MTA, in what looks like the usual agency turf battles, except now given a partisan spin. I doubt there’s going to be any money for Reconstruction (budgeted at $7 billion), let alone expansion (budgeted at $17 billion), and overall this looks like the usual promises that nobody intends to act upon. The problem is that this project is still lurking in the background, waiting for someone insane enough to say what not a lot of people think but few are willing to openly disagree with and find some new source of money to redirect there. And oddly, this makes me think of tariffs.
The commonality is that free trade is not just good, but is more or less an unmixed blessing. In public transport rolling stock procurement, the costs of tariffs are so high that a single job created in the 2010s cost $1 million over 4-6 years, paying $20/hour. In infrastructure, in theory most costs are local and so it shouldn’t matter, but in practice some materials need to be imported, and when they run into trade barriers, they mess entire construction schedules. Boston’s ability to upgrade commuter rail stations with high platform was completely lost due to successive tightening of the Buy America waiver process under Trump and then Biden, to the point that even materials that were just not made in America (steel, FRP) could not be imported. The problem is that nobody was willing to say this out loud, and instead politicians chose to interfere with bids to get some photo-ops, getting trains that are overpriced and fail to meet schedule and quality standards.
Thus, the American turn away from free trade, starting with Trump’s 2016 campaign. During the Obama-Trump transition, the FTA stopped processing Buy America waivers, as a kind of preemptive obedience to something that was never written into the law, which includes several grounds for waivers. During the Trump-Biden transition, the standards were tightened, and waivers required the approval of a political office at the White House, which practiced a hostile environment, hence the above example of the MBTA’s platform problems. Now there are general tariffs, at a rate that changes frequently with little justification. The entire saga, especially in the transit industry, is a textbook example not just of comparative advantage, but of the point John Williamson made in the original Washington Consensus that trade barriers were a net negative to the country that imposes them even if there’s no retaliation, purely from the negative effects on transparency and government cleanliness. This occurred even though tariffs were not favored in the political elite of the United States, or even in the general public; but nobody would speak out except special interests and populists who favored trade barriers.
And Penn Expansion looks the same. It’s an Amtrak turf game, which NJ Transit and the MTA are indifferent to. NJ Transit’s investment plan is not bad and focuses on actual track-level improvements on the surface. The MTA has a lot of problems, including the desire for Penn Reconstruction, but Penn Expansion is not among them. The sentiments I’m getting when I talk to people in that milieu is that nobody really thinks it’s going to happen, and as a result most people don’t think it’s important to shoot down what is still a priority for Amtrak managers who don’t know any better.
The problem is that when the explicit argument isn’t made, the political system gets the message that Penn Expansion is not necessarily bad, but now is not the time for it. It will not invest in alternatives. (On tariffs, the alternative is to repeal Buy America.) It will not cancel the ongoing design work, but merely prolong it by demanding more studies, more possibilities for adding new tracks (seven? 12? Any number in between?). It will insist that any bounty of money it gets go toward more incremental work on this project, and not on actually useful alternatives for what to do with $17 billion.
This can go on for a while until some colossally incompetent populist of the type that can get elected mayor or governor in New York, or perhaps president, decides to make it a priority. Then it can happen, and $17 billion plus future escalation would be completely wasted, and further investment in the system would suffer because everyone would plainly see that $17 billion buys next to nothing in New York so what’s the point in spending a mere $300 million here and there on a surface junction? If it were important then Amtrak would have prioritized that, no? Even people who get on some level that the agencies are bad with money will believe them on technical matters like scheduling and cost estimation over outsiders, in the same manner that LIRR riders think the LIRR is incompetent and also has nothing to learn from outsiders.
The way forward is to be more formal about throwing away bad ideas. Does Penn Expansion have any transportation value? No. So cancel it. Drop it from the list of Northeast Corridor projects, cancel all further design work, and spend about 5 orders of magnitude less money on timetabling trains at Penn Station within its existing footprint. Don’t let it lurk in the background until someone stupid enough decides to fund it; New York is rather good lately at finding stupid people and elevating them to positions of power. And learn to make affirmative arguments for this rather than the usual “it will just never happen” handwringing.
Quick Note: Report on Electrification and Medium-Speed Rail Upgrades
Nolan Hicks has wrapped up nearly a year of work at Marron on a proposal called Momentum, to upgrade mainline rail in the United States with electrification, high platforms, and additional tracks where needed, short of high-speed rail. The aim is to build low- or perhaps medium-speed rail; the proposed trip times are New York-Albany in 2:05 (averaging 109 km/h) and New York-Buffalo in 5:38 to 5:46 (averaging 123 km/h). The concept is supposed to be used US-wide, but the greatest focus is on New York State, where the plan devotes a section to Network West, that is New York-Buffalo, and another to Network East, that is the LIRR, in anticipation of the upcoming state budget debate.
The costs of this plan are high. Nolan projects $33-35.6 billion for New York-Buffalo, entirely on existing track. The reasoning is that his cost estimation is based on looking at comparable American projects, and there aren’t a lot of such upgrades in the US, so he’s forced to use the few that do exist. A second track on single-track line is costed cheaply with references to various existing projects (in Michigan, Massachusetts, etc.), but third and fourth tracks on a double-track line like the Water Level Route are costed at $30 million/km, based on a proposal in the built-up area of Chicago to Michigan City.
In effect, the benefits are a good way of seeing what upgrades to best American industry practices would do. The idea, as with the costing, is to justify everything with current or past American plans, and the sections on the history of studies looking at electrification projects are indispensable. This covers both intercity and regional rail upgrades, and we’ve used some of the numbers in the drafts at ETA to argue, as Nolan does, against third rail extensions and in favor of catenary on the LIRR and Metro-North.
(Update 4-3: and now the full proposal is out, see here.)
Open BRT
BRT, or bus rapid transit, can be done in one of two ways: closed and open. Closed systems imitate rail lines, in that there is a BRT route along the entire length of the corridor; open ones instead take a trunk route, upgrade it with dedicated lanes and other BRT features, and let routes run through from it to branches that are not so equipped, perhaps because there is less traffic on the branches. I complained 14 years ago that New York City Transit was planning closed BRT in the form of SBS on Hylan Boulevard on Staten Island, a good route for open BRT. Well, now the MTA is planning BRT on the disused North Shore Branch of the Staten Island Railway, arguing that it is better than reactivating rail service because buses could use it as an open corridor – except that this is a poor corridor for open BRT. This leads to the question: which corridors are good for open BRT to begin with?
Trunks and branches are good
Open BRT can be analogized to a Stadtbahn system, fast in the core and slow outside it. Like a Stadtbahn, it works best where several branches can converge onto a single route, where the high traffic both requires higher capacity and justifies higher investment; just as grade separation increases the throughput of a rail line, BRT treatments increase those of a bus through greater separation from other traffic and regularity of service.
Unlike a Stadtbahn, open BRT remains a bus. This means two things:
- The trunk route must itself be a strong surface route. It had better be a wide street with room for physically separated bus lanes, or else a city center route that could be turned into a transit mall. A Stadtbahn system puts the fast central portion underground and could do it independently of the street network, or even run under a slow narrow street like Tremont Street in Boston.
- The connections from the trunk route to the branches must themselves be strong bus links. If the bus needs to zigzag on narrow residential streets to get between two wider arterials, then it will be unreliable and slow even if one of the wider arterials gets dedicated lanes. A Stadtbahn system can tunnel a few hundred meters here and there to ensure the onramps are adequate, but a surface bus system cannot, not without driving its cost structure to that of a subway but with few of the benefits of underground running.
The North Shore Branch could pass a modified version of criterion 1, but fails criterion 2. In general, former rail lines are bad for such BRT systems, since the street network was never set up for such connections. In contrast, street networks with a central artery and streets of intermediate importance between it and residential side streets emanating from it, which were never used for grade-separated rail lines, are more ideal for this treatment.
Grids are bad
Street grids eliminate the branch hierarchy of traditional street networks. There is still a hierarchy of more and less important grid streets – in Manhattan, the avenues and two-way streets are wider and more used for traffic than the one-way streets – but there is little branching. Bus networks can still branch if they move between streets, which happens in Manhattan, but it’s not usually a good idea: Barcelona’s Nova Xarxa uses the grid to run mostly independent bus routes, each route mostly sticking to a grid arterial, and the extent of branching on the Brooklyn, Queens, and Bronx bus networks is limited to a handful of short segments like the Washington Bridge.
In situations like this, open BRT would not work. Hylan is possibly the only route in New York that has any business running open BRT. For this reason, our Brooklyn bus redesign proposal, and any work we could do for Queens, Manhattan, or the Bronx, eschews the open BRT concept. The buses are upgraded systemwide, since features like off-board fare collection and wider stop spacing are not really special BRT features but are rather normal in, for example, the urban German-speaking world. Center bus lanes are provided wherever there is need and room. There is more identification of a bus route with the street it runs on, but it isn’t really closed BRT, which is a series of treatments giving the BRT routes dedicated fleets and stations, for example with left-side doors to board from metro-style island platforms like Transmilenio.
What this means more broadly is that the open BRT is not a good fit for most of North America, with its grid routes. Occasionally, a diagonal street could act as a trunk if available, but this is uncommon. Broadway is famous for running diagonally to the Manhattan grid, but that’s not a BRT route but a subway route.
Tokyo Construction Costs
Here is a list of Japanese subways and their construction costs, courtesy of Borners, who has been working on this as well as on a deep dive about London construction costs. I’d been looking for this data for years; someone in comments posted a link to a different sheet summarizing the same data years ago but I couldn’t find it.
Unfortunately, the list isn’t quite good enough to be used for all subway lines. The problem is that the numbers are given in nominal yen for the costs of constructing entire lines, including ones that opened in phases over many years during which inflation was significant. The table of lines and their construction costs in units of 100 million yen/km is as follows, with my best attempt at deflating to 2023 prices, still in units of 100 million yen/km; to convert to millions of dollars per km, the 2022 PPP rate is $1 = ¥94.93, so add 5.3% to all numbers in the penultimate column.
| Line | Cost/km | First works | First opening | Final opening | Year of prices | Cost/km (real) | Confidence |
| Marunouchi | 18 | 1951 | 1954 | 1962 | 1956 | 114 | Medium |
| Asakusa | 46 | 1956 | 1960 | 1968 | 1961 | 257 | Medium |
| Hibiya | 32 | 1959 | 1961 | 1964 | 1961 | 179 | High |
| Tozai | 41 | 1962 | 1964 | 1969 | 1965 | 181 | High |
| Mita | 91 | 1965 | 1968 | 2000 | 1975 | 182 | Low |
| Chiyoda | 69 | 1966 | 1969 | 1979 | 1970 | 236 | Low |
| Yurakucho | 167 | 1970 | 1974 | 1988 | 1979 | 261 | Low |
| Hanzomon | 255 | 1972 | 1978 | 2003 | 1983 | 336 | Low |
| Shinjuku | 235 | 1971 | 1978 | 1989 | 1976 | 433 | Low |
| Namboku | 262 | 1986 | 1991 | 2001 | 1993 | 291 | High |
| Oedo | 311 | 1986 | 1991 | 2000 | 1994 | 343 | High |
| Fukutoshin | 282 | 2001 | 2008 | 2008 | 2005 | 314 | High |
The confidence level is a combination of the length of time it took to build the line and the inflation rate over that period. The Oedo and Namboku Lines opened in stages over a decade, but during that decade Japan had no inflation, and as a result price level adjustments are easy. In contrast, inflation in the 1960s was high but the Hibiya and Tozai Lines were built quickly, so that the uncertainty based on picking a year to deflate to is maybe 10%. The in between lines – Mita, Chiyoda, Yurakucho, Hanzomon – all opened in stages over a long period of time with significant inflation. This makes it hard to use them to answer the question, what was Tokyo’s cost history?
What the numbers suggest is that by the 1970s, construction costs were not much lower than they’d be in the 2000s; Japan having grown steadily in the 1970s and 80s, this means that its ability to afford new subways after the bubble burst in the 1990s was actually greater than in the 1970s. Construction costs have risen since – an extension of the Namboku Line to Shinagawa is budgeted at ¥131 billion/2.5 km and a branch extension of the Yurakucho Line from Toyosu to Sumiyoshi is budgeted at ¥269 billion/4.8 km. Toyosu-Sumiyoshi is in Shitamachi and has multiple canal crossings justifying an elevated cost, but Shirokane-Takanawa-Shinagawa is in easier topography, and while it has multiple subway crossings over a short length, so did the lines built in the 1990s and 2000s – the Fukutoshin Line has, over 9 km, five subway crossings and complex connections at both ends with through-running.
Cos Cob Bridge Replacement
The Northeast Corridor has eight movable bridges in Connecticut; other than one that was replaced in the 1990s, all are considered by Amtrak and Connecticut DOT to be both critical priorities for replacement and also major undertakings. The Bipartisan Infrastructure Law funded two, on the Connecticut and the Norwalk Rivers. The costs are enormous, beyond any justification: the Walk Bridge replacement is funded at $1 billion for a four-track bridge of 200 meters, and the replacement will still be a movable bridge rather than a fixed span with enough clearance below for boat traffic. The cost can be compared with an order of magnitude of tens of millions of dollars for comparable or longer bridges, for examples $50 million for one of the Rhone bridges on the LGV Méditerranée and $32 million for an 800 m viaduct on the Erfurt-Nuremberg line.
The goal of this post is to focus on the Cos Cob Bridge on the Mianus River. Among the eight bridges, it is the one with the least advanced plans for rehabilitation, such that no cost figure is given, but rumors put it in the mid-single digit billions for a viaduct of about 1 km, crossing about 250 m of water. Among the bridges west of New Haven, it is also the one with the most constrained alignment making replacement more necessary to fix the right-of-way geometry: the bridge itself is straight but flanked by two short, sharp curves, and replacement should be bundled with a wider curve.
The NEC Webtool outlines one alignment, with a wide curve, 2,400 meters in radius. The snag is the vertical alignment. The bridge needs to be high enough to clear boat traffic below; I-95 slightly upriver has a clearance below of 14.9 meters (Wikipedia says 21 meters but that’s the top of the deck, not the bottom), and with a typical deck thickness of 1.5 meters it means top of rail needs to be about 16.5 meters above sea level – but the Riverside station 450 meters east of the midpoint of the river has top of rail 10 meters above sea level and the Cos Cob station under the I-95 overpass 450 meters west of the midpoint is 8 meters above sea level. To build it as a high span thus requires rising 8.5 meters over 450 meters.
The current Northeast Corridor plans hew to a much lower ruling grade. The Walk Bridge is being replaced with another movable bridge and not a high fixed span because the standards call for a 1% grade. This is, frankly, dumb. The passenger trains are electric, either commuter rail EMUs or powerful intercity trains capable of climbing 4% grades over a short section, even the medium-speed Northeast Regionals. The freight trains are long enough that what matters isn’t so much the maximum grade as the maximum grade averaged over the length of a train, in which case peaking at 4% over a length of 450 meters is not at all problematic.
With a 4% standard, the question is not about the grade, but about the vertical curve radius. Standards for those are tighter than for horizontal curves. Vertical and horizontal curve radii both follow the formula ar = v^2, but the acceleration limit a is much tighter since there is no tilting or superelevation, and on a crest a high speed also reduces the effective weight acceleration and thus reduces train stability. In Germany, a is limited to 0.482 on a crest and 0.594 on a hallow, both requiring special permission; in Sweden, the German crest value is the minimum limit, with no special dispensation on a hallow. The upshot is that at 250 km/h, the exceptional vertical curve radius is 10,000 m and thus it takes 400 meters just to get to 4%; over a length of 450 meters, the maximum average gradient is 1.125% if the higher acceleration rate on a hallow isn’t used or 1.25% if is and the tracks can only rise respectively 5 or 5.5 meters. To make it 8.5, the speed limit needs to be reduced: at 200 km/h, the vertical curve radius is 6,400 meters and then over 225 meters the trains can get up to 3.5% and, if it’s symmetric, over 450 they can climb 7.9 meters, and if it’s asymmetric then they can climb more than the required 8.5%. It’s dirty but it does work.
The issue is then how this affects construction. I don’t know why the Connecticut bridge replacements are so expensive, beyond the observation that everything in Connecticut is exceptionally expensive, usually even by the standards of other Northeastern American rail projects (for example, infill stations), let alone European ones. The local press articles talk about staging construction to avoid disturbing the running track, and if this is the main difficulty, then building a new bridge 50 meters upriver should be much easier, since then the only part of the project interfacing with the existing track is the track connections on firma.
Whatever it is, a multi-billion dollar pricetag is not believable given the required scope. More difficult construction has been done for two orders of magnitude less on this side of the Pond. On a different mode but in the same region, the 10-lane 1.4 km long Q Bridge cost $554 million, around $790 million today, which, relative to the size of the bridge, is still around an order of magnitude cheaper than Walk and more than an order of magnitude cheaper than what Cos Cob is rumored to be.
16-Car Trains on the Northeast Corridor
The dominant length of high-speed rail platforms in China, Japan, South Korea, and Europe is 400 meters, which usually corresponds to 16-car trains. The Northeast Corridor unfortunately does not run such long trains; intercity trains on it today are usually eight cars long, and the under construction Avelia Liberty sets are 8.5 cars long. Demand even today is high enough that trains fill even with very high fares, and so providing more service through both higher frequency and longer trains should be a priority. This post goes over what needs to happen to lengthen the trains to the global norm for high-speed rail. More trains need to be bought, but also the platforms need to be lengthened at many stations, with varying levels of difficulty.
The station list to consider is as follows:
- Boston South Station
- Providence
- New London-HSR
- New Haven
- Stamford
- New York Penn Station
- Newark Penn Station
- Trenton
- Philadelphia 30th Street
- Wilmington
- Baltimore Penn Station
- BWI
- Washington Union Station
Some of these are local-only stations – the fastest express trains should not be stopping at New London or BWI, and whether any train stops at Stamford or Trenton is a matter of timetabling (the headline timetable we use includes Stamford on all trains but I am not wedded to it). In order, allowing 16-car trains at these stations involves the following changes.
Boston
South Station’s longest platforms today are those between tracks 8 and 9 and between tracks 10 and 11, both 12 cars long. To their immediate south is the interlocking, so lengthening would be difficult.
Moreover, the best platforms for Northeast Corridor trains to use at South Station are to the west. The best way to organize South Station is as four parallel stations, from west to east (in increasing track number order) the Worcester Line, the Northeast Corridor and branches, the Fairmount Line, and the Old Colony Lines, with peak traffic of respectively 8, 12 or 16, 4 or 8, and 6 trains per hour. This gives the Northeast Corridor tracks 4-7 or possibly 4-9; 4-7 means the Franklin Line has to pair with the Fairmount Line to take advantage of having more tracks, and may be required anyway since pairing the Franklin Line with the Northeast Corridor (Southwest Corridor within the city of Boston) would constrain the triple-track corridor too much, with 12 peak commuter trains and 4 peak intercity trains an hour.
The platform between tracks 6 and 7 is 11 cars long, but to its south is a gap in the tracks as the interlocking leads tracks 6 and 7 in different directions, and thus it can be lengthened to 16 cars within its footprint. The platform between tracks 4 and 5 is harder to lengthen, but this is still doable if the track that tracks 5 and 6 merge into south of the station is moved in conjunction with a project to lengthen the other platform.
Of note, the other Boston station, Back Bay, is rather constrained, with nearly the entire platforms under an overbuild, complicating any rebuild.
Providence
Providence has 12-car platforms. The southern edge is under an overbuild with rapid convergence between the tracks and cannot reasonably be extended. But the northern edge is in the open air, and lengthening is possible. The northern edge would be on rather tight curves, which is not acceptable under most standards, but in such a constrained environment, waivers are unavoidable, as is the case throughout urban Germany.
New London
This is a new station and can be built to the required length from the start.
New Haven
The current station platforms are only 10 cars long, but there is space to expand them in both directions. The platform area is in effect a railyard, a good example of the American tradition in which the train station is not where the trains are (as in Europe) but rather next to where the trains are.
A rebuild is needed anyway, for two reasons. First, it is desirable to build a bypass roughly following I-95 to straighten the route beginning immediately north of the station, even cutting off State Street in order to go straight to East Haven rather than curve to the north as on the current route. And second, the current usage of the station is that Amtrak uses tracks 1-4 (numbered west to east as in Boston) and Metro-North uses tracks 8-14, which forces Amtrak and Metro-North trains to cross each other at grade from their slow-fast-fast-slow pattern on the running line to the fast-fast-slow-slow pattern at the station. In the future, the station should be used in such a way that intercity trains either divert north to Hartford or Springfield or go immediately east on a flying junction to the high-speed bypass toward Rhode Island, without opposed-direction flat junctions; the flying junction is folded into the cost of the bypass and dominates the cost of rebuilding the platforms, as the space immediately north and south of the platforms is largely empty.
Stamford
Stamford has 12-car platforms. Going beyond that is hard, to the point that a more detailed alternatives analysis must include the option of not having intercity trains stop there at all, and instead running 12-car express commuter trains, lengthening major intermediate stops like South Norwalk (currently 10 cars long) and Bridgeport (currently 8) instead.
To keep the mainline option of stopping at Stamford, a platform rebuild is needed, in two ways. First, the station today has five tracks, a both literally and figuratively odd number, not useful for any timetable, with the middle track, numbered 1 (from north to south the numbers are 5, 3, 1, 2, 4), not served by a platform. And second, the platform between tracks 3 and 5 can at best be lengthened to 14 cars, while that between tracks 2 and 4 cannot be lengthened without moving tracks on viaducts. This means that some mechanism to rebuild the station should be considered, to create four tracks with more space between them so that 16-car platforms are viable; this should be bundled with a flying junction farther east to grade-separate the New Canaan Branch from the mainline.
A quick-and-dirty option, potentially viable here but almost nowhere else, is selective door opening, at the cost of longer dwell times. Normally selective door opening should not be used – it confuses passengers, for one. However, here it may be an option, as intercity traffic here is unlikely to be high; traffic today is 323,791 in financial 2023, the lowest of any station under consideration in this post unless one counts New London. The only reason to stop here in the first place is commuter ridership, in which case mechanisms such as restricting unreserved seats to the central 12 cars can be used.
New York
Penn Station has multiple platforms already long enough for 16- and even 17-car trains, including the one we pencil for all high-speed intercity trains in the proposal, platform 6 between tracks 11 and 12, as well as the two adjacent platforms, 5 and 7. (Note that unlike at New Haven and Boston, platform numbers at Penn increase south to north, that is right to left from the perspective of a Boston-bound traveler.)
Thank the god of railways, since platform expansion requires a multi-billion dollar project to remove the Madison Square Garden overbuild in the most optimistic case; in a more pessimistic case, it would also require removing the Moynihan Station overbuild.
Newark
Newark Penn Station’s platforms are in a grand structure about 14.5 cars long. Thankfully, they extend a bit south of it, producing about 16 cars’ worth of platform on the west (southbound) side, between tracks 3 and 4; as in New York, track numbers increase east to west. On the east side, PATH interposes between the two tracks, which have a cross-platform transfer from northbound New Jersey Transit trains to PATH. The platform structures and their extensions do have enough length to allow 16-car trains – indeed they go as long as 18 – but the southern ends are currently disused and would require some rehabilitation.
Trenton
Trenton has a 12.5 car long southbound platform and an 11.5 car long northbound platform. There is practically no room for an expansion if no tracks are moved. If tracks are moved, then some space can be created, but only enough for about 14 cars, not 16.
However, traffic is low, the second lowest among stations under consideration next to Stamford. The suite of Stamford solutions is thus most appropriate here: selective door opening with only the middle 12 cars (naturally the same as at Stamford) open to commuters, or just not stopping at this station at all. The only reason we’re even considering stopping here is timetabling-related: trains should be running every 10 minutes around New York but every 15 between Baltimore and Washington, or else significant expansion of quad-tracking on the Penn Line is required, and so a local stop should be added as a buffer, which can be Trenton or BWI, and BWI has twice the current Amtrak traffic of Trenton.
Philadelphia
30th Street Station has 14-car platforms. Selective door opening is basically impossible given the high expected traffic at this station, and instead platform expansion is required. There is an overbuild, but the tracks stay straight and only begin curving after a few tens of meters, which gives room for extension; from the north end to the overbuild to where the tracks begin curving toward one another to the south is 15.5 cars, and there is room north of the overbuild between the tracks.
Whatever reconstruction project is needed is helped by the low traffic at these platforms. SEPTA uses the upper level of the station, with tracks oriented east-west. The north-south lower level is only used by Amtrak, which could be easily reduced to three platform tracks (two Northeast Corridor, one Keystone) if need be, out of 11 today. Thus, staging construction can be done easily and intrusively, with no care taken to preserve track access during the work, as half the station platforms can be closed off at once.
Wilmington
Wilmington is frustrating, in that there is platform space for 16 cars rather easily, but it’s on inconsistent sides of the tracks. Track numbers increase south to north; track 1 has a side platform, there’s an island platform between tracks 2 and 3, and then track 3 also has a side platform on the other side, extending well to the east of the island platform. The island platform and the track 1 platform are about 12.5 cars long, and the track 3 side platform is 13.5 cars long. Thus, an extension, selective door opening, or a station rebuild is required.
The island platform can be extended about one car in each direction, so it cannot be the solution without selective door opening. Both side platforms can be extended somewhat to the west: the track 1 platform can be extended to 16 cars, but it would need to be elevated in the narrow space between the track viaduct and the station parking garage; the track 3 platform can be extended in both directions, avoiding a new elevated extension over North King Street.
If for some reason an extension of the track 1 platform is not possible, then selective door opening can be used, but not as reliably as at lower-traffic Stamford or Trenton, and overall I would not recommend this solution. A station rebuild then becomes necessary: the station has three tracks but doesn’t need more than two if SEPTA and Amtrak can be timetabled right, and then the removal of either track 1 or track 2 would create space for a longer platform.
Baltimore
Baltimore Penn has seven tracks, numbered from south to north 1, 3, 4, 5, 6, 7, F. Their platforms are 10 to 13 cars long. Northbound trains are more or less forced to use the platform between tracks 1 and 3, since the way the route tapers to a three-, then four-track line to the east forces all eastbound trains to use mainline track 1; this platform is rather narrow at its east end but has space to the west for a 16-car extension. Westbound trains can use either the platform between tracks 4 and 5 or that between tracks 6 and 7, with tracks 4 and 6 preferred over 7 as they reach the express westbound track (track 5 stub-ends). Both platforms can be extended, with the platform between tracks 6 and 7 requiring a one-car extension to the east where a ramp down to track level for track workers exists whereas that between tracks 4 and 5 has ample unused space to its west.
BWI
The two side platforms at BWI are just under 13 cars long. However, nowhere else on the corridor is an extension easier: the station is located in an undeveloped wooded area, with space cleared on both sides of the track so that tree cutting is likely unnecessary west of the tracks and certainly unnecessary east of them.
The station itself needs a rebuild anyway, due to already existing plans to widen it from three to four tracks. This is required to enable intercity trains to overtake commuter trains anyway, unless delicate timetabling on triple track is used or another part of the Penn Line is set up as a four-track overtake. The plans are rather advanced, but platform extensions can be pursued as an add-on, without disturbing them due to the easy nature of the right-of-way.
Washington
Washington is set up as two separate stations, a high-platform terminal to the west and a low-platform through-station to the east on a lower level. Track numbers increase west to east, the western part taking 7-20 (though only 9-20 are high and wired) and the eastern part 23-30. None of the western platforms is long enough, but multiple options still exist:
- The platform between tracks 9 and 10 has room for an extension.
- The platforms between tracks 15 and 16 and between tracks 16 and 17 look like they already have extensions, if not open for passengers.
- The platforms between track 17 and track 18 and between tracks 19 and 20 are only 12 cars long, but tracks could be cannibalized in the open air to make a long enough platform, especially since the reason track numbers 21 and 22 are skipped is that there used to be tracks there and now there’s empty space.
- The platform between tracks 25 and 26 is long enough, and could be raised to have level boarding.
The existing platforms that can be extended easily are sufficient in number, but probably not in location – it’s ideal for the platforms to be close together, to simplify the interlocking as trains have to be scheduled to enter and leave the station without opposite-direction conflicts. If it’s doable even with a split between platforms separated by multiple tracks then it’s ideal, but otherwise, the extra work on tracks 17-20 may be necessary, converting a part of the station that presently has six tracks and four platforms into likely four tracks and two platforms.
Conclusion
All of this looks doable. The hardest station, Stamford, is skippable if selective door opening is unviable after all and a rebuild is too expensive. Among the other stations, light rebuilds are needed at Boston, Wilmington, and maybe Washington; New Haven needs a more serious rebuild as part of the bypass, but the station platforms are a routine extension where there is already room between the tracks. The most untouchable station, New York, already has multiple platforms of the required length at the required location within the station.
Pedestrian Observations 