More on Suburban Circles
In the last post, I criticized the idea of large-radius suburban circle, using the example of the Berlin Outer Ring, at radius 10-26 km from city center. In comments, Andrew in Ezo brought up a very good point, namely that Tokyo has a ring at that radius in the Musashino Line, and ridership there is healthy enough to fill a train every 10 minutes off-peak. Of course, the Musashino Line’s intersections with the main JR East lines, like Nishi-Kokubunji and Minami-Urawa, have the ridership of a city center station in Germany rather than that of a station 25 km out. So to discuss this further, let’s drop midsize cities like Berlin and look at an actually large city: New York. Consider the following possible circle in New York, at radius 20-25 km:
See full-size version here (warning: 55 MB).
Most of the radial extensions I’ve already discussed in previous posts – for example, here. Here these extensions go somewhat further in order to meet the ring, including at Newark Airport, on Staten Island, in Bay Ridge, at Floyd Bennett Park, in Canarsie, at Starrett City, near the Queens/Nassau County line, and in Yonkers.
The ring is 151 km, of which around 87 km would be above ground, mostly replacing highways like the Belt Parkway to reduce costs. Of note, this cannot be done adjacent to an extant highway – the fast car traffic deters nearby development, making transit-oriented development impossible. So key road links around the region have to go, which is fine, since people should be transitioning from driving to taking trains. With some additional elevated construction including through City Island, across the Long Island Sound, and in low-density parts of North Jersey where demolishing houses even at $1 million per unit is cheaper than tunneling, construction costs could be reduced further. But it’s still a $20-25 billion project at average world costs, maybe $15 billion at Nordic or Korean or Southern European or Turkish costs.
The only way to pay off the costs of such a line, not to mention to fill enough trains to support frequency that can take untimed transfers (at worst a train every 10 minutes), is to have very high ridership, on the order of 400,000-500,000 per day. This is for a line that misses Manhattan and all of the big secondary job centers, like Downtown Brooklyn and Long Island City. Is this plausible?
The answer is not an obvious no. Sufficiently aggressive TOD could plausibly create ridership. But it’s still questionable. There are really a few different forces pulling such a line in different directions:
- Using existing rights-of-way to reduce costs, hence the use of the Belt Parkway and not the denser development around Avenue U or even Flatlands.
- Serving secondary nodes like JFK, Coney Island, EWR, and Yonkers. Potentially it would be plausible to veer inward in New Jersey in order to hit Downtown Newark, at the cost of a few extra kilometers of tunnel, making the line radial from Newark’s perspective, whereas the line as depicted above is circumferential from Newark’s perspective since it goes around city center.
- The need to connect to radial subway and commuter rail lines, which means serving stations, opening plausible infill stations, and extending some lines toward the ring.
There are different ways to resolve this tension; the line I depicted is not the only one. For example, a higher-cost, higher-ridership version could veer inward in the Bronx and Queens, aiming to connect to Flushing and Jamaica and then replace the AirTrain JFK, leading to a ring of radius closer to 16 km than to 20-25.
I only bring this up to point out how many things have to work if you want such a ring to work out. Keeping costs to even semi-reasonable levels requires demolishing highways and engaging in aggressive TOD, which is only possible in an environment of total political victory over NIMBY and pro-car interests (note: these two are not the same!).
This is not the history of the Musashino Line. The Musashino Line originates in a freight bypass around the built-up area of Tokyo, which eventually turned into a circumferential passenger line. This is why it connects to the radial lines near but not at the busiest regional stations – at Nishi-Kokubunji and not Kokubunji, at Minami-Urawa and not Urawa, at Shin-Matsudo and not Matsudo or Kashiwa.
But even when the line is new, there are always compromises on right-of-way. Uncompromised right-of-ways are 100% possible, but not at 25 km radius, because the cost is too high to always go to the most important secondary centers. They happen when the radius is smaller, like Paris’s 8-10 km for M15, because then ridership can be high enough (M15 projects nearly a million riders a day). Farther away, ridership drops and costs rise because the line gets longer faster than per-km costs drop, so compromises are inevitable.
I am not proposing the ring above as a definitive crayon. I’m just mentioning it as something that highlights the difficulties of circumferential public transportation in the suburbs. Even as it is, the strongest segment of the ring is most likely the one in the city taking over the Belt Parkway, which could replace busy buses like the B15, B1, B3, B6, and B82. The suburban segments are weaker – there isn’t that much commuting across the Hudson that far north, and building up such commuting requires heavy commercial TOD in Yonkers, Mount Vernon, and New Rochelle.
There is substantial commuter traffic across the Tappan Zee bridge, people who live in Rockland County and work in Westchester County, but that takes the line much further north. If you do that, you might as well try to replace I-287 and run the line over the Outerbridge Crossing. I commuted on 287 for 27 years. It’s a miserable road.
I don’t see any of this as doable from any perspective. Nobody in this country appreciates rail transit the way Europeans do.
Except there is a good likelihood that your next president will be someone who has spent about 40 years commuting by rail to his day job in DC!
There is substantial commuter traffic across the Tappan Zee bridge
No there isn’t. I’m not going to dig out the most recent American Community Survey. The last one I looked at, most people who live in Rockland, work in Rockland, then Manhattan, Bergen County New Jersey and then Westchester. And a lot of those jobs aren’t wherever you want to put a train. Or where they live.
(There is substantial commuter traffic across the Tappan Zee, but it’s mostly Rockland -> city. You’re right that Rockland/Orange -> Westchester is pretty trivial.)
There are trains and buses from Rockland County to Manhattan that don’t go through Westchester. People commuting from Rockland to Manhattan can use those.
A 20km-radius circle line in London would absolutely work, and most of it would easily support frequent trains. Connecting Watford, Heathrow, Kingston, Croydon, Bromley and Romford to one another would IMO support service every ten minutes (train lengths depending). These are all big regional centres with a lot of jobs, residents and onward transport links, all situated 15 to 25 km from Charing Cross in central London.
Yeah, but there’s no ROW, you’d have to tunnel so much…
Absolutely. But it’s a very different argument to say that such lines wouldn’t work operationally (as you do for Berlin) than to say that such lines would cost a lot (as you do for New York and London). This route wouldn’t be an immediate construction priority, but if the infrastructure existed (like it does in Berlin) it would certainly see decent ridership.
Not only is it cheaper to build than tunnel (or standard heavier-rail metro or regional-rail) but is ideal for the longer distance. It is far more acceptable elevated than regular rail (or road) because these things are silent. Higher speeds and higher acceleration to those speeds, thus reduced travel times. One of you techno-geeks should model it. In my clunkier way I have been messing around with the proposed Melbourne Loop (90km but because of the bay it is only 2/3 of a circle; it does service the main airport) but someone should do it for this NYC circle. Bögl claim costs of around €30m-50m per kilometre of double-track line with elevated track. Incidentally, while I didn’t write it in my last comments on this topic I did think it w.r.t. Shanghai or any of the Chinese mega-cities: an elevated maglev loop. One of those mega-cities (popn. ≈15m), Chengdu, has signed a deal with Bögl.
If this system rally has ask the benefits it claims to have, why isn’t there a single example of it in regular operation?
@Herbert ” …why isn’t there a single example of it in regular operation?”
In a very real sense there is. Two very hi-speed (Shanghai Transrapid; Chūō Shinkansen, Japan) and 4 low-speed urban maglevs (Linimo-Japan, Changsha-China, Incheon-S. Korea, Beijing-S1). This version uses the same technology developed by Thyssen-Krupp/Siemens for the TransRapid and reformulated by a long-established rail company (Max Bögl) into a new hybrid form, in between the low-speed and the high-speed types currently in use. Like all new tech, especially in transport, developments take time though this one is pretty quick. Bögl began development in 2010–of course the critical tech was fully developed/licensed by T-K and represents about 5 decades of work–and they signed a deal with Chengdu in 2018 to build a test-track, and the first trains were shipped earlier this year. Chengdu is one of those Chinese mega-cities growing its Metro system from nothing to one of the world’s biggest in about a decade. Incidentally it has two “regional rail” lines to serve two of its outer districts (Dujiangyan and Pujiang) that are HSR, which kind of explains their interest in this hybrid system from Bögl that can achieve 150km/h. About 5m of its ≈15m population live in the outer zones, so my speculation is that they are looking at ways of linking them all up more efficiently than any of the current options. They might even be looking at it for an outer ring. They already have an inner ring.
This is just a branded proprietary version of maglev. Maglev is good for faster-than-HSR lines, because there is nothing else with that speed except airplanes, which have their own obvious downsides. But for urban lines that will never exceed 150km/h (due to acceleration and curve limits)? Legacy rail can do that equally well, and legacy rail is not incompatible with all your existing infrastructure, and does not put you at the mercy of a private company which cares about its profit rather than your city’s transportation quality.
Almost every point you make is wrong.
Yes, like every tech development of the modern world, it is proprietary though not the basic underlying stuff (which is licensed from Thyssen-Krupp and which is now also independently being further developed in China much to the Germans annoyance). There are currently at least 4 companies across 4 countries (Japan, S.Korea, China, Germany) all of whom are major rail nations too, actively developing related urban applications of maglev. If any one of these has some kind of breakthrough, clearly the others would emulate it. A bit like Apple shaking up the cell-phone market in 2006 and today every one of the 10 billion phones on the planet resembling and functioning like an iPhone despite thousands of Apple patents enclosing its walled garden.
Clearly legacy rail cannot do that equally well is not true. The speed thing is really about quickly getting up to whatever speed is appropriate for the route. The combination of fast acceleration & deceleration, silent operation, tight turning arcs and high cant provides something steel rails cannot match. For these reasons there have always been people who said that maglev’s advantages were better suited to urban applications than high-speed intercity applications. There are 5 out of 5 such real-world operating urban lines with only one attempt at ultra-speed intercity (Chūō Shinkansen) still many years from completion.
Then there is the killer feature of maglev: almost zero maintenance, of either track or vehicles. For busy urban networks this is kinda a big deal. Further, due to their speed (ability to attain speed over much shorter distances) a line needs fewer trains (40% fewer on some calcs.). This is why the arguments about interoperability or being handcuffed to one technology company are not valid. Anyway, like the proprietary argument, it falls to bits once it starts succeeding and being adopted more widely. And often interoperability is simply the worse feature that traps one into old tech. Certainly it is a very high bar against change in existing cities with big legacy metro systems and that is why you see these experiments in China. Though one could argue that for NYC replacing its decrepit system by jumping over old tech might be a better option than the painful and slow upgrade path they are on (fitfully). These maglev systems could be retrofitted into all existing infrastructure (tunnels, stations) but not without some kind of extended shutdown. That is, unlike the remarkable changeover to new trains and platform-aligned doors on Paris-M1 without any interruption to existing service. For these reasons it may be more likely to succeed in the regional rail market and where its speed is an even bigger advantage, combined with more acceptable elevated structure. Oh, and with its lightweight structure and light trains, could be fitted onto many existing big bridges without even stealing lanes from cars.
Having said that, another breakthrough for these companies (and Bögl has all the right expertise) could be to make their maglev systems compatible with steel rails if only to make such transitions pain-free. So a line could be modified incrementally in overnight steps without interrupting existing service.
I am highly skeptical about the no maintenance claim part. Even just looking at standard concrete viaducts, they still need a lot of maintenance if they need to sustain a multi-decade lifespan and those have no embedded electrodes. Accounting for the embedded coils, how does de-lamination and concrete fracture affect the performance and reliability of the system over time? It’s good China is putting a few real world examples of low speed maglev in operation. We would have data on the reliability data in a few decades.
Then there’s the noise issue. I know there’s a lot of opportunity to get a lower noise line compared to steel rail, but looking at this video of the S1 Maglev in Beijing, it sounds no different from a regular steel rail to me. maybe because it’s not muffled compared to monorails that also use 3rd rail, but have the tires and current collectors shielded.
Also regarding using existing infrastructure, is the SCMaglev used on the Chuo Shinkansen not designed to fit into the same track width as standard gauge track bed? Though the trainset is much narrower (2.9m for the L0 series vs 3.36 for the N700) as the rest of the width is taken up by the outer edges of the U shaped track. The Beijing S1 maglev also looks like it can fit in the same track width as a standard gauge train, but the switching issue still remains, so the advantages need to be overwhelming enough for a conversion to take place.
Those points are fair enough but I think you are tending to treat all the issues as if maglev is really the same as steel wheels except without the wheels. Take maintenance. Not only is it self-evident in the way in which electric vehicles will be so much simpler and so much less prone to failure and need far less maintenance than ICE. But even issues such as the structural support is far less prone to stress that affects its lifespan. I’m not sure concrete plays much of a role at all since the support is steel or aluminium and is a fraction of the mass needed for standard rail, not to mention freight rail. The latter causes point stresses in a massive stress wave as the train bogies pass over, such that even the strongest structure has to be made flexible to absorb that wave (if not it will crack sooner or later). It is resonance combined with mass that causes damage to structures and why those structures (for vehicles including trains; bridges etc) are prone to catastrophic failure. Maglev not only is a fraction of the weight but is evenly distributed over the entire trains length and track. It is orders of magnitude lower stress on the structure. This is how Bögl has engineered supporting spans of 72 metres which is remarkable and has all kinds of advantages in construction and urban ROW etc. (In fact I suppose we can remain a bit sceptical until a working length of track is built and used exhaustively.)
I don’t quite get why so many on this blog, including Alon, are so sceptical about this stuff. Even putting aside cost issues (where in the Anglosphere costs per km of anything exceeds maglev costs at their wildest). The Shanghai Transrapid has been operating since January 2004–almost 17 years–and the only time it has been temporarily closed was due to a customer-caused fire on-board (ie. zip related to it being maglev). It is true that it is a bit unfortunate that it is China where transparency is lacking but the operation still speaks for itself. Guest engineers who have visited and talked with their technical people have verified that its maintenance is truly astounding, estimated at less than 2 weeks per decade. Everyone on this site knows how intensive the maintenance of both track, signalling and trains must be for standard steel-wheel, and what a significant burden this is on the real long-term costs of running standard rail. (Though one has to admit that the Shanghai line is also special in that it only runs a single train per track so doesn’t have to cope with many issues most railways have to, and a remaining “weakness” of maglev is the track switching which is a bit cumbersome as it requires the movement of the whole structural span. I don’t know what the experience of those urban maglevs is on this issue.)
As to noise, again I’d have to say it is beyond argument. Though here we’re talking urban lower-speed maglevs, apparently “at 300 km/h it is much quieter than a TGV moving at only 88 km/h”. However I can’t compare with those urban maglevs you mention and perhaps there are reasons for that. But with the Transrapid the only noise is the rush of air. I mean, what else is there? There is no contact by anything with the track and there are no moving parts (except the doors) and no motor (except non-moving linear electric). OK, while I have stood on the platform to watch as the Transrapid arrived and departed, and rode inside the cabin, I haven’t been on the ground below its elevated track as it rushed past at 430km/h. Aside from those things, I also would say that there is a public perception issue. I agree with you that noise for low-speed elevated steel-wheel (or combined with rubber-wheeled like Paris) can be largely controlled–to a degree–but it is the perception by the public that it will be noisy that provokes NIMBYism for any proposed elevated route. I believe maglev can largely overcome that perception, though not completely as there are recalcitrants everywhere (like on this blog!). This, combined with its ability for tight turns (min. turning arc 45m) and high cant (8° though of course a maglev could do anything you wanted including probably a 360° loop because the train is superglued to that track; just like it could easily exceed human g-force limits), ability to cope with high gradients, means it has unique and very real advantages for building thru dense urban environments, both in an engineering sense, in a cost sense and in a public approval sense.
Re the Chūō Shinkansen, I think it rather confirms my points on these issues, in that IMO it is an unfortunate mix of the two technologies. Why would one want to burden a maglev with the need to use wheels until it reaches 150km/h? Plus the need for liquid nitrogen! The Transrapid is the only version that can maintain its elevation above the tracks via on-board batteries (ie. such is the low power consumption and the nature of its mag levitation). I understand that SCmaglev has its theoretical advantages and I would have been a bit sceptical, not to mention nervous, about ‘active management’ of that few centimetre air gap at >400km/h but here we are after 17 years of absolutely impeccable operation. I can only think the Japanese chose their version of maglev as a distinguishing thing from the Germans or others, and possibly in misplaced nationalism. I note that Japan has not been very successful in exporting its standard HSR technology (though some of it is in China’s trains today). I think that that will be the case for maglev.
Re compatibility with standard steel track, it can be done and was a feature of early versions in maglev experimental programmes. Note that the fact that the Chūō Shinkansen has wheels doesn’t mean it can use regular track, because those are rubber wheels! (More maintenance!). Indeed those zany Americans (Powell & Danby) who promoted their version of maglev as being able to use existing steel rails! (The hyperloop of its day?)
When all is said and done, it will come down to performance and we’ll have to see how the Bögl version of medium-speed maglev for cities works out in Chengdu over the next few years (with the proviso that it being China, we may not necessarily know the truth of any decision not to go forward with it). On paper at least it seems a more promising implementation than the current versions of low-speed maglev. And the seemingly auto-scepticism, much like the report of Mark Twain’s death, are much exaggerated.
China to build high-speed maglev test line CHINA plans to start construction next year of a 200km maglev line in Hubei province to test operation of a prototype maglev train at speeds in excess of 600km/h.
David Briginshaw, 04 Oct 2019.
No, it’s you who gets everything wrong.
Proprietariness – so what if multiple companies are offering maglev? Each one is proprietary and incompatible with the others. If you want to extend or maintain your system, only one company can do it, and they can extort you for whatever they wish.
Legacy rail – Acceleration is irrelevant because legacy rail acceleration is already limited by passenger comfort. Noise is not a real issue with rail, not even on elevated lines (if built with concrete). Tight turning and cant are not much of a feature either (lines should generally be built in straight lines to minimize travel time and transfers, and when building with TBM tight turns are never needed).
Maintenance – that maglev requires zero maintenance is a marketing claim, and unlikely to be true.
In short, this is just a fad, like monorail a few decades ago, and should be avoided for the same reason, at least until the maglev manufacturers can get together and make an interoperable standard.
To quote the world bank, “Maximum acceleration should not exceed 1.3 meters per second squared.” This as Eric points out is not for technical reasons, but is a standard for passengers.
Well–not exactly, provided you’re willing to go a bit further out. About 75% of a right of way that encircles 80% of London is already in place–but outside the M25. The question, of course, is ridership:
Ridership prospects are not looking good here.
Tonbridge to Redhill supports one three-carriage train per hour. You could maybe double this with onward connections on each side but I don’t see it getting further than that.
Gatwick to Reading could support three trains per hour (this is officially planned) but many of these people are going to Reading and Gatwick which are not on your route.
North of there the line misses all the important centres that side of London (Slough, Watford, Heathrow, Wycombe).
The Harlow to St Albans section could actually support high frequency and is not a ridiculous idea (I recall this kind of proposal floating around in the late noughties). The A414 road which runs along this route is busy.
Oh I know. I don’t necessarily think this is a good idea (at least without massive TOD in Surrey), but I’m just pointing out that a ROW does exist for an outer London orbital if desired.
There are some rail studies knocking around somewhere for some new services linking Guildford and Woking via that line to Medway towns and Gravesend. Called the R25 and R26 I think. Minor rail improvements for two half hourly services. There are some other studies for more expensive schemes that link various suburban branches in SE London through South London to SW London as start for new outer London services mainly Via Croydon. But no detailed plans.
Isn’t the main point of circle lines that they are inside a network of radial lines. Connecting a radial system with a circle in the edges of the radial lines seems pretty useless. No one wants to commute out on a radial line outwards, then take a ride on a long outer circle, and then connect to a radial line inwards again.
There are regional rail lines that I did not depict on the map to avoid clutter around Midtown.
See full-size version here (warning: 55 MB).
I haven’t giggled that much in a long time. At least you managed to avoid randomly splattering stops like one of the RPA fantasy maps did. There is an awful lot of them.
Yeah, it’s the NY crayon equivalent of this: figure out how to optimize something and see that it’s still on the speculative-to-lolzy spectrum.
That said: if you can get a circle that hits Fordham, Flushing, Jamaica, JFK, Newark, etc. at the same cost, it’s not an obviously terrible idea. It’s just hard to get to all these places at sub-80% tunnel.
Alon, I think this encapsulates the goal: ” if you can get a circle that hits Fordham, Flushing, Jamaica, JFK”
More specifically, your proposal manages to think too small (suboptimally serving neighborhoods in Bronx and Queens with densities well over 15,000 people/sqkm) and too big (leaning too heavily into the idea of a full circle.) There are basically four destinations on the entire western and southern half of your line: Coney Island, a Staten Island Rail hub, EWR Airport, and Downtown Newark–none of which are served all that well. Everything else is low density sprawl. At the same time, there are dozens of dense neighborhoods and regional centers–many of them poorly linked–from Fort Lee to JFK Airport. A line connecting them, particularly if you use the George Washington and Whitestone Bridges, is as compelling as basically any subway extension in the outer boroughs. Besides, connecting to Amtrak at Crotona, LIRR at Jamaica, and JFK Airport instantly slashes journey times for basically any trip between Westchester/Upstate/New England and Long Island/Queens/JFK which is probably more valuable than cutting journey times on the other half of the line: from Philly/Central Jersey to…Bay Ridge?
Plus, it could be done with just 25% of the route length in a tunnel:
This is pretty good, but it could be better!
– Rather than hook the line onto the Whitestone (which I don’t think has the loading capability to carry trains anyways) you could just continue tunneling under the relatively shallow East River from College Point to Soundview, and then use White Plains Road to connect to Tremont Av. That would basically railstitute a pretty busy bus route, the Bx39, and actually serve another transit desert. Neither approach to the Whitestone is particularly dense anyways.
– Rather than hook into JFK where most people will either have a long walk to terminals or need to transfer to the AirTrain anyways, I would go west after Federal Circle under Conduit before linking up to the future Junius-Livonia transfer and terminating at Broadway Junction. This would railstitute yet another busy bus, the B15.
In a similar vein, if the Triboro RX or something like it were to get built, rather than use the Hell Gate approach (too high and sloped to connect to trains in Astoria, may not have enough tracks for both this and future NEC demand, awkward transfers in the Bronx) I would hook the RX east after Jackson Heights, connect to LaGuardia, and then go to Hunts Point and Yankee Stadium and possibly a newly built regional rail hub at 149th St. This would railstitute both the Q70 and the Bx6.
Always a pleasure when you link ancient posts of yours that talk about something I’d never thought about.
Well, lines on a map that are unlikely to happen. Interesting thought exercise nonetheless.
About NIMBY/Pro-Car. You bet. Pro-Car people are HAPPY to build a new 8-lane “expressway” through *your* living room so that they can get where they want to go 1 minute faster (offer valid for the first week – after that, there is just as much congestion as before).
They do this secure in the knowledge that there is no need for a freeway near their suburban/exurban housing and don’t even need to be active NIMBYs because nothing will come close to their backyard.
> replacing highways
Surely it would cheaper to just blow up all the bridges and tunnels so people stop getting tempted to move around at all.
They’d be good for carrying the trains. If he’s going to close down the Belt Parkway all the traffic coming over the Verrazano Narrows Bridge will have to go to the Brooklyn Queens Expressway. After an hour or so the gridlock will discourage additional people from attempting it. Keep the bridges, they can carry the almost empty trains.
Some amorphous person or persons is proposing closing the Belt Parkway or you are?
Ye and it’s variants would work.
Ya all have ta get together and decide on something less ambiguous. Unless yer all happy with getting other people confused. Or youse all like being misunderstood.
For the fun of it, I tried to see of such ring would be possible for a smaller city (Zürich).
It’s fun looking at this and imagining which groups of NIMBYs would have the greater apoplectic shock – I think I’m stuck between Tenafly and City Island, hah.
Anyway, two quick thoughts:
1. Between Paterson and Newark, why do you choose to follow the GSP instead of the former Erie Newark branch? The advantage of the latter is that it lines you up towards downtown Newark, which although you’d need to tunnel under either Broad or McArthur would also put you on an already-existing commuter path.
2. How did you choose your route through Long Island? I don’t know the exact numbers, but does Great Neck have the numbers to make ploughing through the existing development worth it? I thought that using either the Cross Island (which is spitting distance from Queensboro CC) or the Van Wyck (which brushes both Flushing and Jamaica).
Both cases, to me, seem like you’re following the Musashino line’s goal of avoiding existing centers – but that’s because of the freight element. Since this line is (presumably) not running freight, and because there are existing ROWs towards the circumferential CBDs, it seems more cost-effective (from my unprofessional eyes) to hit the various centers. And in the LI route, it strikes me as (alongside Tenafly and New Rochelle routes) as falling on the far side of a political victory against NIMBYs – in this case, it seems more like crushing the NIMBYs into dust.
Suburban circle lines or circles lines in general seem to make most sense when people want a transit option that goes between suburbs while skipping the central city/downtown area. Multiple suburbs must be work/play/residential/educational, etc. locations. If there isn’t a lot of desire to go between suburbs than it doesn’t really make that much sense.
Why not crayon a ring (or rings) for Paris instead? Paris has both an overcrowded transit in the city center, and a good amount of destinations 20 km away from the city center (Versailles, airport, Marne-la-Vallée etc.).
Doing this for New York City is similar to Inception — a dream within a dream within a dream… we can only dream on.
Because Paris is really good at building circumferential transit, the only big change I’d recommend is burying T3 and making it an intermediate ring betweeen M2/M6 and M15. What Paris needs is more radial transit.
I thought you made an important point about this crayon line be radial for Newark while being circumferential for Manhattan. I’d hazard to guess that a successful circumferential line is really a series of radial corridors for secondary nodes strung together, where the circumnavigation is a secondary, almost accidental operational feature. Is that true for Tokyo?
Also, would all your points on suburban circles hold true for suburban lines that go in parallel to the primary node, for waterfront cities where the metropolitan sprawl is a half circle rather than a full circle? Thinking of a line like the Eglinton Crosstown Line in Toronto.
“a successful circumferential line is really a series of radial corridors for secondary nodes”
That is one purpose – the other purpose is allowing trips to the core for people who don’t live on a radial line, by taking the circumferential line for a couple stops and then transferring to the radial line.
(Note that in an densely enough populated area, one doesn’t require “nodes” of higher density, but rather enough population density at any location to justify building a line.)
For sure, but to be successful the non-transfer ridership needs to be high enough to drive the frequency to create good transfers?
I really don’t know which of the purposes is dominant. Maybe it varies by location.
If the radial line is high frequency (every 2-4 minutes), which it probably is if your city is large enough to be building circumferential rail, then there is no need to time transfers because the wait is so short anyway.
Also, the circumferential line should ideally have shorter trains with higher frequency to reduce that part of the transfer time.
I think of Eglinton as an attempt at a grid. If it were optimized for circumferential service, it would bend south in order to meet the Bloor-Danforth Linee and the Lakeshore GO lines.
Good point. Quasi-circumferential would bend towards the water at some point. Thanks.
https://www.fnp.de/frankfurt/frankfurt-bahn-ring-sbahn-hauptbahnhof-stadtteil-tunnel-neu-sued-nord-13904680.html Frankfurt may be getting a suburban ring…