The Rockaway Cutoff

When I went to an IRUM meeting nearly two years ago, the participants crowed about the possibility of restoring rail service on the Rockaway Cutoff. New York urban planner and technical activist David Krulewitch recently posted his proposal in a comment, showcasing multiple ways of reusing it for faster connections between Midtown and the Rockaway branches of the A, serving JFK and/or the Rockaways. Although the possibility has raised excitement among most local transit activists (some of whom have posted fantasy maps in the various subway forums including such an extension), I’m more skeptical.

First, the potential for JFK service is limited. The reason is that the Rockaway Cutoff only reaches Howard Beach, making it just a faster version of the A. The AirTrain is technologically incompatible with any other transit system in the region: it’s a vendor-locked Bombardier technology, of the same type used on the first two SkyTrain lines in Vancouver, in which the trains are driverless and propelled by linear induction motors placed between the tracks. This system allows trains to climb steeper than usual grades, and the maximum grade used on the AirTrain is 5.5%, considerably more than the usual for a normal subway or regional EMU (though less than the absolute maximum).

In addition, the needs of the mainline regional system and the subway are different from those of an airport people mover. A people mover needs very high frequency at all times, which is why such systems are normally driverless. In contrast, most subways are not driverless, and I do not know of a single mainline railroad that is driverless. Driverless operation requires some serious upgrades to electronics, and those upgrades are pointless if used only on a single line. If instead the JFK connection has a driver, then frequency will necessarily be very low, since there isn’t too much airport demand, and this will depress demand even further.

Although the current AirTrain system suffers from the lack of a one-seat ride to Manhattan, the situation is not too bad. Jamaica offers a very frequent LIRR connection to Manhattan at all hours, and Howard Beach offers a frequent if not fast connection to Brooklyn. This requires multiple transfers to reach most destinations, but this is not a major problem for locals who are traveling light. It’s a bigger problem for locals with luggage and even more so for tourists, but a one-seat ride to Penn Station, as proposed in LIRR connection proposals, is not too useful since most hotels are too far north. Even Grand Central is at the southern margin of Midtown proper.

For an honest estimate of how much demand there is, let us look at airports with very good transit connections. At Charles de Gaulle, 6 million passengers board at the RER station per year, 20% of airport traffic, and another 3 million use the TGV. At Frankfurt, 11% of passengers use the S-Bahn, and 15% use the ICE. Neither airport has a subway connection. Heathrow, which does have an Underground connection, has a total of 13 million Underground boardings and alightings, 20% of traffic (see data here); I do not know the ridership of the two mainline rail connections to Central London, but a thesis studying air-rail links puts the mode share as of 2004 at 9%. Assuming the train usage in Paris, New York could expect JFK to see 4.6 million boardings, or 9.2 million boardings and alightings; assuming that in London, New York could expect 13 million. The AirTrain’s current ridership is 5.3 million. Although the extra ridership would be useful at low cost, the higher cost of allowing mainline or subway trains to use the AirTrain tracks may be too high.

More importantly, 13 million passengers a year – an upper bound more than a median estimate in light of Frankfurt and Paris’s lower ridership – do not make for very high frequency by themselves, and therefore JFK could at best be an anchor rather than the primary ridership driver. Airport-only trains would be quite lonely; one of Krulewitch’s proposal’s most positive aspects is that it never even mentions premium express services such as Heathrow Express, which tend to underperform expectations as passengers prefer to ride cheaper local trains. Thus, not only would it be expensive to do an infrastructure and technology retrofit to permit direct Midtown-JFK service, but also the market for it would not be very large.

This brings us to the second possible market: the intermediate stops on the Rockaway Cutoff. They may seem useful, but in fact the development is elsewhere. Observe the land use maps of Queens Community Boards 6 and 9, which host most of the Cutoff: along the Cutoff’s right of way, the primary uses are single-family residential, with only a little commercial. Moreover, the commercial development is often very auto-oriented, for example at Metropolitan Avenue. Indeed, the only proposed station with significant dense development is Rego Park, which is on the LIRR Main Line and could be restored without restoring an entire line. Rezoning near the other stations is possible, but why not rezone near existing subway stations first?

In general, development in the US along linear corridors follows arterial roads, not railroads that haven’t seen passenger service in many decades. In the area in question, the primary north-south commercial artery is Woodhaven Boulevard; for service to the intermediate areas, the proposal should be evaluated against a light rail line on Woodhaven, providing local service from Queens Boulevard to Howard Beach and hitting multiple subway transfer points but not the airport.

The third market posited, fast service to the Rockaways, is the weakest. The stations in the Rockaways are some of the least busy in the subway system, with only a few hundreds of thousands of annual boardings each. They only support 15-minute service, with half of the A trains terminating at Ozone Park; since there are two Rockaway branches, the less busy only gets a shuttle except at rush hour, when there is enough demand for a few direct trains. Even with 15-minute service, it’s expensive to serve an area so far away with a flat fare; until a series of fare unifications, the subway charged a higher fare to stations in the Rockaways.

The problem with the Rockaways is that stations are too far from Manhattan and too lightly populated for it to be otherwise. Moreover, service along the LIRR to Penn Station using the Cutoff is about 18 km long measured from the intersection of the Cutoff with the A at Liberty, and service along the R is 16 km to Lexington and 19.5 to Times Square; service along the A is about 21.5 km long to Penn Station and 22 km long to Times Square, longer but not very much so. The main advantage of the R is that it hits Midtown proper better, rather than skirting it on 8th Avenue, but there’s practically no speed advantage – about 6 kilometers of travel distance and 2 station stops, translating to perhaps ten minutes.

As appealing as sending a single local subway service from the Queens Boulevard Line along the Cutoff to serve the Rockaways and give direct service to every branch, there would be a large demand mismatch; moreover, service to Forest Hills, which has nearly twice as many riders as all Rockaway stations combined, would be degraded.

LIRR service to the Rockaways could be better, but only if it’s modernized. The way it’s run today – infrequently, not very quickly, and expensively – it has no appeal. Far Rockaway has 4,500 weekday boardings on the subway (with a travel time of 1:06-1:14 to Times Square), and 158 average of boardings and alightings on the LIRR (with a travel time of 0:50-1:00 to Penn Station). Cutting another ten minutes from the LIRR travel time to Far Rockaway isn’t going to change anything as long as operating patterns remain as they are.

But if operating patterns are modernized, is there a point in service along the Cutoff? It saves very little distance measured to Far Rockaway: 21 vs. 24.5 km. It’s more useful farther west in the Rockaways, but those are less useful areas to serve – those are the areas with the lowest subway ridership, whereas Far Rockaway’s ridership is merely below average. Although the ridership would not be as pitiful if LIRR charged subway fares for in-city service and provided reasonably high speed and frequency, and it could be studied further as a case of an in-city S-Bahn line, there are more worthwhile S-Bahn destinations on the LIRR, for examples southeastern Queens, Hempstead, Bayside, and Great Neck. The main problem is that the Rockaway Beach branch would still have too little ridership to justify high frequency, and the round-robin proposal would have the same frequency-splitting effect on the stations except Far Rockaway and its immediate vicinity as running two separate branches; each station may have frequent service, but half the trains would take too long.

Finally, the three above-described markets – JFK, neighborhoods between Rego Park and Howard Beach, and the Rockaways – cannot all be served at the same time. The intermediate neighborhoods are free, but it’s impossible to serve both JFK and the Rockaways without an additional branching, reducing frequency even further. This means that the two markets can’t be combined to create more powerful demand. It’s one or the other – either the 13 million boardings and alightings one could optimistically expect of JFK, or the 4.5 million boardings times an appropriate growth factor one could expect of the Rockaways. Neither is high by S-Bahn standards; measured in ridership per terminus excluding short-turns, the least busy RER line, the RER C, has 20 million riders per terminus.

Because of the low potential ridership of the Rockaway Cutoff, I suggest New York transit advocates look elsewhere first. Service to JFK could be beefed up with sending surplus Amtrak trains to Jamaica for an interchange, and service to the Rockaways first with modernizing regional rail and second with having it take over the Far Rockaway branch of the A if there’s demand. If there’s higher than expected growth in demand, then the Cutoff could be activated, at as a low a cost in 15 years as today. But for now, the low cost of activating the Rockaway Cutoff comes hand in hand with low benefits.

Quick Note: No More Track Maps

I regret to say that I’ve taken down the track maps by Rich E Green that I’d hosted, in accordance with requests by him and by his employer, to whom he sold the maps. This involves breaking past links; I will put notices in past posts of mine that link to them, including a brief description to what is seen in the maps when necessary, and I encourage others to do the same.

What’s the Infrastructure’s Highest Value?

A piece of land and infrastructure may have multiple uses. Land might be needed for urban development or for a highway. A two-track structure might be needed for freight or passenger service. A right-of-way might be needed for multiple kinds of rail, or a road, or a power line easement, or a park. In all cases, the correct policy choice is to allocate the land to the use that has the highest social value, and this use depends on the situation at hand. It should not be allocated to whatever one fancies.

Concretely, let us consider the following cases:

1. The High Line. Occasionally, railfans grumble about the linear park, and say it should’ve had passenger rail service instead; read the comments on Ben Kabak’s post on linear parks, or New York City subway forums. But in reality, the High Line is very useful as a park in a busy neighborhood that doesn’t have other parks. In contrast, it’s nearly worthless as a transit line: it’s parallel to a north-south subway that’s operating well below capacity, it would be nightmarishly difficult to connect to any existing line, and the only east-west service it could possibly be useful for is connecting to 14th Street, not the most important job destination in the city.

2. The Northeast Corridor in Rhode Island, south of Providence. The expansion of MBTA commuter rail southward into sprawling exurbs is a major failure of regional transportation policy. Providence is not all that congested by the standards of the larger Northeastern cities; auto-oriented commuter rail toward it is doomed to fail, and near-downtown parking is cheap and plentiful. (The commute market from Warwick and Wickford Junction to Boston is trivial.) In contrast, the line is perfect for intercity service, since it has relatively gentle curves outside city limits, and is straight south of East Greenwich. The South County project not only costs $200,000 per weekday rider, but also makes poor use of high-speed track. Since the line is more important as high-speed rail than as a commuter line, Amtrak should be more aggressive about demanding that commuter projects create their own capacity.

3. The Northeast Corridor in Maryland, north of Baltimore. For the same reasons as the MBTA extension’s eventual failure, MARC underperforms north of Baltimore. Although the line has extensive three- and four-track segments, the bridges are two-tracked, and high-speed rail should again be given priority, including canceling commuter rail if necessary. Ironically, because of more extensive four-tracking, the need for bypasses around Wilmington and perhaps North East, and the at-grade track layout, Perryville is quite easy to connect to Philadelphia by commuter rail without interfering with intercity rail.

4. Caltrain to San Jose, the MBTA to Providence, MARC to Baltimore. In contrast with the situation in points #2-3, those three lines are all useful commuter lines; they are all similar in that they connect two distinct cities that share suburbs, with a rump extension that exists purely for show (into Gilroy, Perryville, and soon to be Wickford Junction). Any and all high-speed rail use of these corridors should permit a reasonable frequency of commuter trains, with timed overtakes when possible and full four-tracking otherwise. On Caltrain, in particular, interference with commuter rail is one reason why the chosen Pacheco Pass alignment is inferior to the Altamont alignment.

5. The Lower Montauk Line. Despite perennial railfan desires (and an empty Bloomberg campaign promise, since scrubbed from his campaign website) to restore passenger service, there’s not much point in regional rail that stub-ends in Long Island City. To give an idea how much demand there is, the LIRR currently runs 5 trains per day per direction into Long Island City. Thus, the line is more useful for freight trains than for passenger trains. This will change if, and only if, there is a way to connect the line to Manhattan through the existing LIRR tunnels, or perhaps new tunnels, but then the cost is going to be orders of magnitude higher than just restoring service.

6. Urban freeways, e.g. the BQE. American freeways were built at a time when, even more so than today, land was allocated based on political power rather than any sort of social consensus or market pricing concept. While Japanese cities have to make do with 4-lane freeways due to high land costs and strong property rights protections, American cities demolished entire neighborhoods to make room for freeways with wide exclusion zones around them. The land occupied by some would be more useful for additional neighborhood housing growth than it is for a freeway. For example, the BQE hogs prime real estate in Williamsburg, right next to the under-capacity Marcy Avenue subway station, and to a lesser extent in the rest of Brooklyn and Queens, and this land could be used for high-density development instead.

Regional Rail to Lower Manhattan

Staten Islanders’ desire for a subway connection got me thinking again about my previous proposal for a tunnel from Staten Island to Manhattan, possibly with a cross-platform connection to Brooklyn and New Jersey. From all points of view, it is desirable to build a regional rail hub near Fulton Street, and connect it to nearby commuter lines, creating a second pole for an RER- or S-Bahn-like system in New York, in addition to a Midtown pole centered around Penn Station. My intention in this post is to discuss tradeoffs in choosing how to build it.

As the source of the ARC and ESA cost overruns is the station caverns in Manhattan, the Fulton Street station should be minimalistic: as close as possible to the surface (closer to 20 meters underground than to 55), without a full-length mezzanine, and with only four tracks, one to each of Midtown, Brooklyn, New Jersey, and Staten Island. It should under no circumstances look like the ESA extravaganza. This economizing means it’s difficult to build this as a terminal: ideally the station box would be built and then tunnels would be built to all four destinations, making two two-track lines.

The length of this station should be 300 meters, to accommodate 12-car trains, but if it’s too hard to build within the available footprint, then a shortening to 10- or even 8-car trains is feasible. Regional trains in both Paris and Tokyo are usually only 200 meters long. In addition, unlike its Parisian inspiration, Chatelet-Les Halles, Fulton Street need not have very wide platforms. When I took the RER A and changed trains at Chatelet, at 8:40 in the morning, the platform was about as crowded as that of a normal subway station, and needed much less than its full width of 17 meters. Indeed, the Chuo Line, with far higher peak load than anywhere in the West, terminates on a single 10-meter-wide island platform. A single-level four-track station with a cross-platform transfer should be about 30-35 meters wide; since it is too wide for most Lower Manhattan Streets, another option is a bilevel station with two tracks per level, with useful cross-platform transfers, and about 15-18 meters wall to wall per level.

The best time to have built this project was right after 9/11. Because of the connection to World Trade Center, it could have been funded out of 9/11 recovery funds, which instead went to the Calatrava PATH terminal. In addition, the rebuilding of WTC and the PATH terminal could have been done in tandem with the new train station, making its placement far easier. Alas, this did not happen, and all available space east of the WTC site is gone.

The difficult part in building this is the train station, not the access tunnels. Access tunnels can be built very deep using tunnel-boring machines and can even go directly underneath existing subway tunnels. For example, Paris Métro Line 14, whose construction cost was low relative to its depth and Paris’s underground complexity, goes parallel to and under Line 7 for a short segment, and a few kilometers of the RER D were constructed alongside the preexisting RER A tunnel. While I’m not aware of similar examples outside Paris, this shows that it is doable. In contrast, I don’t know of new stations built right underneath preexisting stations in parallel except for some high-cost US projects like the BART Market Street Tunnel Sixth Avenue Subway (thanks to Adirondacker for the correction). Stations-under-stations in oblique configurations exist in Paris, but the biggest station, namely Chatelet-Les Halles, avoids this.

The upshot is that many streets in Lower Manhattan are suitable for new tunnels, and it’s even possible to have access tunnel go deep under building foundations. However, since nearly all suitable north-south streets already host subways, a new station is more difficult. The option for a station under an existing subway station exists, but would be expensive. Let us then scout alternative locations.

Although it’s desirable to have cross-platform transfers, this configuration is more difficult than a cross configuration, in which the Brooklyn-New Jersey line goes east-west in Manhattan. This is because under a north-south configuration it may be difficult to have the Brooklyn-New Jersey tracks dive and turn west fast enough to connect to the desired New Jersey end. An east-west configuration also permits narrower single-level station caverns.

Finally, we should consider the fact that peak employment in Lower Manhattan is around Wall Street, judging by where skyscrapers are located, whereas the main station to connect to is at Fulton Street. In both cases, the key location is well east of the WTC site. Thus a Cortlandt Street location is suboptimal, and a West Street location, where there’s enough space for everything, is too far away. We will repeatedly look at the location relative to existing subway stations in Lower Manhattan: close is good, intersection is not so good.

With the above in mind, here are the options:

East-West Lines

Liberty Street

Advantages: wide enough for everything for a long stretch, from Cortlandt to beyond William. A possible 18*300 box exists from Nassau to Cortlandt, requiring demolition of at most a few low-rise buildings west of Church Street; another box with a slight curve exists from Church to William. There’s a 200-meter stretch that’s 25-meter wide from building edge to building edge. Zucotti Park permits a main entrance with enough space for pedestrians that commuters wouldn’t saturate the neighborhood’s narrow streets. Liberty is close to quite close to the center of Lower Manhattan. Brushes off against the existing Cortlandt Station on the R, but stays away from the other subway stations.

Disadvantages: far from Fulton Street (200 meters); closer to the Wall Street subway station than to the Fulton Street station on the 2/3 and J/Z. Also far from one of the easiest if not the most convenient locations for a north-south line. (But see at the end of the post for update.)

Vesey Street

Advantages: one block from Fulton. There’s an easy location for a north-south line (even a four-track one) next to City Hall, right north of Vesey. St. Paul’s Churchyard can act as the equivalent of Zucotti Park for the Liberty option. Intersects just one subway line, the E. There’s a very easy 200-meter box beginning at Broadway and continuing east.

Disadvantages: far from where most Lower Manhattan workers want to go to. A 300-meter box requires going under Vesey north of WTC, where building foundations may be a problem, or through narrow right-of-way under Ann. Continuing west requires threading the narrows between 1 WTC and 7 WTC, and continuing east requiring threading the Ann Street narrows.

John/Dey Streets

Advantages: one block from Fulton. Almost as close to where most people work as Liberty. Close to the Fulton Street stationhouse, which may be developed into a major retail destination because of the subway station.

Disadvantages: even a 200*15 box would require a few low-rise demolitions. To the east it could thread the John Street narrows, but to the west it would dip under WTC foundations and the memorial. A 300-meter box is impossible without going under skyscraper foundations (fortunately, nothing supertall). Crosses right under the J/Z and 4/5, though the active constraint for depth is probably the WTC foundations to the west.

North-South Lines

City Hall Park

Advantages: enormous space for everything, including a 35*300 box that misses all building foundations, all subway stations, and possibly all subway tunnels. Can bend to the south under Broadway and go under a mid-rise building to the north. A lot of space for pedestrian circulation both in the park and on Broadway.

Disadvantages: closer to the City Hall subway stations than to Fulton – in other words, located about half a subway stop farther away from the CBD than Fulton, which is already at the margin of the main cluster of skyscrapers. If it were picked, then there would probably be a need for a South Ferry train station serving the southern end of Lower Manhattan, which is about a kilometer from the southern end of this location – and South Ferry is so close to the water the station would have to be deep-level.

Broadway

Advantages: close to everything. The street offers about 21 meters of width until well south of Zucotti Park, which is more than enough for a box, and the only stretch narrower than about 24 is at Fulton and John, where the buildings are lower-rise.

Disadvantages: right under and parallel to the 4/5. If this is a four-track option, then this means putting the station at levels -2 and -3. It’s no big deal by the standards of Chatelet-Les Halles or especially Auber, but the RER A was expensive for its time. And even the Chatelet train box was built between two Métro stations (Chatelet and Les Halles, hence the name) rather than under a station.

Church Street or Nassau Street, taking over a subway line

Advantages: could leverage some existing structures, no interference from the subway for rather obvious reasons; under both options the J/Z would terminate at Chambers, where there are existing tracks for it, and under the Church Street option the R would be rerouted along a short new tunnel (cheap by the standards of what we’re talking about here) and thence the Nassau Street tracks. Nassau is literally in the center of the Fulton Street complex.

Disadvantages: beyond the immense subway disruption this would cause, the tracks are old and have insufficient loading gauge. In addition, Nassau, the less disruptive option and the one that is closer to the peak employment center, is a narrow street and even its two subway tracks are on separate levels (see track map). Existing track geometry may impose unreasonable curves, causing squeal.

Greenwich Street

Advantages: serves WTC. Already has a grand terminal because of PATH, reducing the likelihood that politicians will spend billions on starchitecture. I believe that when the street is remapped after WTC construction is complete, it will be 18 meters wide from building to building, permitting an ample train box, even a four-track bilevel one. There’s an easy way to continue both north and south, allowing shallow construction, right underneath the 1 and PATH.

Disadvantages: too far west of where most Lower Manhattan employment is. The PATH terminal may impose unreasonable constraints. Taking over the 1 is a possibility, but presents the same difficulties as taking over the R or J/Z, and would also require an additional South Ferry station, at great depth. The proximity to WTC means the national security agencies may shit bricks about such good transit designs as shallow platforms, maximally free pedestrian circulation, and an open station. Of course the TSA and associated paranoid agencies should be (and is) fought whenever it is required, but ideally agencies should avoid situations that invite a fight they may lose.

Pearl/Water Street

Advantages: Pearl is wide enough for everything north of Fulton, and Water is wide enough south to Pine but with a 22-meter narrows between Fulton and John. Free of obstructions, as the only intersecting subway line, the A/C, is already deep. Can continue south fairly easily as well as north, curving west under the Brooklyn Bridge ramps.

Disadvantages: far east of the existing train station – 300 meters just to the 2/3 at Williams. On a similar note, east of most development; the block east of Pearl and north of Beekman is a parking lot. Conflicts with Second Avenue Subway Phase 4, but this is a small problem as the box could be built with provisions for a two-track subway underneath at little additional cost.

Gold Street

Advantages: close to both the subway station and most Lower Manhattan development. Crosses the A/C line but no station. Can continue north very easily because of the Brooklyn Bridge ramps.

Disadvantages: some room to the north of Fulton, away from the development, but very little south of Fulton; even 250*15 would brush up against the southern end of the street, which is flanked by skyscrapers. In a similar vein, continuing south requires bending west under William or maybe east under Pearl, and both require tunneling under buildings with three-figure height.

Dutch Street, or between Broadway and Nassau

Advantages: both options offer the ability to thread through some gaps in the skyscrapers, going under lower-rise buildings or lower-rise sections of the skyscrapers and limiting the amount of demolition required. Literally at the same site as the subway station. Quite close to most commercial buildings.

Disadvantages: even a 200*15 box would probably require deep-level construction to limit demolitions. Has some leeway to the south and north (assuming shallow construction) but much less than options using continuous streets. In other words, very expensive.

Update: another option is to route the Staten Island-Manhattan tunnel through Brooklyn, in which case it comes into Manhattan from the east, allowing a four-track east-west option. Both Vesey and Liberty present the option of the line to Grand Central branching north under West, then diagonally once deep enough that it can freely go under private property. Vesey presents the additional option of going north under Greenwich, which conflicts with nothing. Conversely, Liberty has the advantage of being south of the 9/11 memorial rather than south of skyscrapers, allowing the turn to West to have much wider curve radius (about 200 meters) without going under any building or the footprint of the Twin Towers.

Megaregional Change

Just as transportation networks can create a new megaregion, so can they work to destroy one. Back in 1910, the golden age of manufacturing centralization, the US had a megaregion, namely the core formed by the quadrilateral whose vertices are Boston, Milwaukee, St. Louis, and Baltimore. Outside this quadrilateral, there were almost no large industrial cities, and the main exceptions were either right outside and represented extensions (Kansas City, the Twin Cities) or in California (San Francisco), representing a separate manufacturing network.

The formation of the Northeast megaregion was really a replacement of the old megaregion with a different system. The US used to have a general core area and a periphery. It was never perfect – the North’s dominance of the South was only complete after city regions developed elsewhere, so there was never a total dominance of the manufacturing belt. But it was still far richer than the periphery, and each city had a separate industry to specialize in. In contrast, what we see today is different: there are still core and periphery regions, but instead of one giant core, we have a spikier core, spread relatively evenly nationwide. The Northeast’s four major cities are all core, but there are core cities everywhere, so in a sense we get a core and periphery in each major region of the US. Megaregions occur along clusters of core cities surrounded by their nearby dependencies.

Just as the new, smaller megaregions are bound by high-speed rail or by regular rail and freeway networks, the old one was bound by the emerging freight rail network. Lower transportation costs made it easy to manufacture everything in one place and ship it elsewhere. Once a core-periphery model sets in, it takes a large difference in income to make it worthwhile to start locating factories elsewhere.

I forget which book I got this from (I think The Bottom Billion by Paul Collier), but it took until the postwar period for first-third world income disparity to grow to the point that American companies started offshoring factories. Until then, what is now the first world consistently had higher economic growth than what is now the third world, even absent colonial relationships. Of course within a country the costs of moving factories are lower and so the wealth disparity required to change the core-periphery dynamic is different, but the principle is similar. For decades, there wasn’t much city growth in the South. California grew very quickly, since it had gold and then oil and needed to manufacture its own goods since transportation costs across the Rockies were too high for it to import everything from the East. But, as Jane Jacobs quotes Henry Grady on the situation of the region around Atlanta:

I attended a funeral once in Pickens county in my State. They buried him in the midst of a marble quarry: they cut through solid marble to make his grave; and yet a little tombstone they put above him was from Vermont. They buried him in the heart of a pine forest, and yet the pine coffin was imported from Cincinnati. They buried him within touch of an iron mine, and yet the nails in his coffin and the iron in the shovel that dug his grave were imported from Pittsburg. They buried him by the side of the best sheep-grazing country on the earth, and yet the wool in the coffin bands and the coffin bands themselves were brought from the North. The South didn’t furnish a thing on earth for that funeral but the corpse and the hole in the ground.

Of course, something similar to what happened in the US between about 1910 and the 1960s is happening on a global scale: the dominance of the US, Europe, and Japan is in decline, and third-world economic growth is now consistently above first-world growth.

Paul Krugman suggests that this change in agglomeration patterns comes from further income growth, noting that China today looks a lot like the US of 1910. While he talks about it in terms of city specialization, this is equally true in terms of the location of the core. China’s core today is a contiguous region stretching from Guangdong to just north of Shanghai, plus Beijing. It’s entirely possible that in fifty years it will look different – that the small cities between the megaregions around Shanghai and Guangdong will rust while new cores will develop around large interior cities.

An HSR Country is a Centralized Country

1950s’ Japan was a fairly monocentric country, in which everything was in Tokyo. When it built the Shinkansen, the expectation was that fast travel nationwide would make it easier to do business in the other cities, reducing centralization. Instead, the opposite happened: the Shinkansen made it easier to get to and from Tokyo, increasing centralization. At the same time, the US, which forwent its rail system and built the Interstate system, saw its manufacturing belt disintegrate, with production moving to the South. If we think of high-speed rail as a nationwide version of rapid transit, then we get the same pattern seen in cities, in which transit works hand-in-hand with centralization.

As with transit, there are exceptions – namely, Germany. Germany’s point-to-point HSR network coexists with its polycentric layout. What this suggests is that HSR does not create centralization so much as reinforces it when it already exists. The Shinkansen made the rest of Japan more dependent on Tokyo, and the TGV has made most of France more dependent on Paris, but that’s because the existing traffic patterns were such that only lines connecting to or near the capital would be competitive. Thus, only connections from a provincial city to the capital are fast, and the loss of province-to-province connectivity (more precisely the deemphasizing of such connections, since both Japan and France continued to build nationwide freeway networks) leads to a loss of independence in the provinces. Lille has redeveloped with the help of the TGV, but this has involved marketing itself as a city close to Paris, Brussels, and London. It’s not the same as Paris itself, which gets by without needing to tout how close it is to London or Lyon.

This does not detract from the fact that HSR can lead to development. Lille really did redevelop with the help of the TGV. Many cities right outside Ile-de-France, such as Tours, are seeing a property boom fueled by fast train links to Paris. The Shinkansen helped bind the Tokaido-Sanyo megaregion, redeveloping cities at appropriate commute range, for example Mishima. The issue here is that a city bound by a megaregion is no longer an independent region, for all that entails.

The consequence in the US is of course not that HSR will turn the country into a single-city country. The US is too big and decentralized. But within each region, HSR is going to bind megaregions together in a way that leads to the same loss of independence. In the Northeast, we can expect the region to be far more dependent on its four primary cities, especially New York. Providence would benefit from being about 20 minutes from Boston and 1:15 from New York, but it would be drawn fully into those two cities’ orbits. The economic development it can expect is not the sort that still clusters in New York and Boston, but rather the lower-end development that is worthwhile to outsource to lower-cost regions. It would be competing with Middlesex County, New Jersey for jobs, rather than with Midtown or even with Downtown Brooklyn. Likewise, in California, we can expect to see more dependence on Los Angeles ans San Francisco, with Bakersfield and Fresno relegated to secondary status.

What I’m doing here is describing in grimmer terms what is cheerfully described as development in various pro-HSR brochures. An advanced economic system, including fast transportation, will lead to specialization, and this includes specialization into center and hinterland. This is new economic geography: reduced transportation costs lead to more rather than less specialization, and HSR reduces transportation costs with respect to time for certain kinds of work.

Ironically, what this implies is that the best way to preserve independence is to not build any binding infrastructure, or engage in national planning. Toronto will remain independent of New York so long as there are separate currencies, separate national markets, and different infrastructure clusters; there’s not much demand for New York-Toronto travel (the air market has about 100,000 monthly passengers in both directions; the top intranational market, New York-Miami, has about a million), so there will not be any new infrastructure between New York and Toronto anytime soon, which will further reinforce those cities’ distinct economies. Montreal, which occasionally seeks HSR to New York as economic development, is doing so explicitly to have an economic basin separate from Toronto’s; it is willing to sacrifice economic independence to achieve some independence from Toronto.

This seems to have been Jane Jacobs’ view in The Economy of Cities and Cities and the Wealth of Nations. Although she wrote about the economic links of the original manufacturing belt megaregion, she wrote even more about the economic links within each city region, and had a dim view of megaprojects; in Cities and the Wealth of Nations, she also rejected national currencies, and proposed city-states as a replacement for nation-states. I have little doubt that she would oppose HSR, just as later in life she came to oppose rapid transit and support jitneys.

Not believing that everything Jacobs said is gospel, I take a more neutral view. The HSR-bound megaregion is more efficient in a way than having ten independent cities along the Northeast Corridor, just as New York is better off today as a single city than it would have been as separate cities if the 1898 amalgamation had not gone through, despite the loss of independence Brooklyn has endured. However, this efficiency is achieved via a brutal division of labor between the cities: some become core, some become periphery.

Of course, this may be sufficient consolation in the small cities that would love to become suburbs of successful cities. At the time of this writing, Fresno’s unemployment rate is 15%, and Bakersfield’s is 14%. The Central Valley is seeking prisons as a form of job creation. Providence is better off, but despite recent economic growth and slow absorption into Greater Boston, it’s one of the higher-unemployment regions in the Northeast. Loss of independence is not necessarily bad. But conversely, the fact that this development is good does not mean that it will really turn the smaller cities into productive city regions; it will just make them more comfortable peripheries of cities in which there’s so much that the residents don’t have to care about intercity travel.

Consensus and Policing

The recent spate of mass arrests and brutality at various Occupy demonstrations is not a matter of bad cops like John Pike or even bad politicians like Michael Bloomberg. Tear gas, pepper spray, and rubber bullets have occurred throughout the US over the last ten years, as a result of a new theory of crowd control, coming from the broken windows approach toward ordinary crime.

The interest for consensus urbanism is that although the approach seems geared toward protecting consensus values, in reality the values the police is protecting are manufactured from scratch, and are only shared by a minority that treats itself as normal. There is no social consensus leading to the police approach toward public protest – indeed, public sympathy toward Occupy Wall Street soared after the first mass arrest. The new authoritarian approach is the result of an internal development within law enforcement. Just as a truly consensual urban space needs to have ample opportunities for individuality (as opposed to just individualism), community policing needs to treat communication with the people as a two-way avenue.

Although there are sporadic media reports of protester violence, in reality both my and my friends’ observations of nonviolence at the encampments and the history of the past ten years suggest otherwise. In brief: on the heels of the anti-globalization protest in Seattle in 1999, police departments decided that their previous strategy of good-faith negotiations with protesters had failed, and switched to a strategy of surveillance, free speech zones, and selective use of arrests and non-lethal violence, including pepper spray. Under this strategy, communication is one-way, and negotiations with authority are pointless, as anti-war protesters discovered in 2003 when they were denied permits despite months of negotiation. As with broken-windows policing, the police treats protests as disorderly conduct that must be punished in order to promote middle-class values.

The part about middle-class values is where consensus versus authoritarianism comes into play. Although middle-class values seem like consensus, they really are not in this case. In contrast with the broken-windows policing of turnstile jumping and similar petty quality-of-life crimes, in which much of the impetus came from community requests, in the case of protesting the violence comes entirely top-down.

The creation of a fictitious middle-class mentality that considers all protest distasteful masks how much of a minority interest it is. The Progressive movement needed to create a middle-class American identity from scratch and impose it on immigrants and other tenement dwellers (to the point of opposing tenement improvement efforts, which would distract from the need to suburbanize); French nationalists needed to impose Parisian French on a country that did not speak it; modern-day police departments impose conformity and distaste for protest on a population that dreads unemployment and has rock-bottom approval for such major institutions as Congress. Everyone is a deviant in one way or another. At best, what society can do short of recognizing this fact is to list special personal interests and weird habits that are more acceptable, and relegate the others to people’s private homes.

The importance of solving the problem of police authoritarianism by consensus is that doing it any other way will just replace one master with another. To me, nonviolence, consensus, and democracy are not just abstract values. They come from the impossibility of improving things by force. Any political force powerful enough to control the police is by definition more powerful than the police, which means it will be able to exercise even more control over people; this is why communist revolutions always result in repression. The only way to improve the situation is to make the political force one that is comprised of ordinary people rather than an elite vanguard, and one that works by persuasion and communication rather than by raw power.

Update: I forgot to talk about this, but one way to see that the cops really do see themselves as values enforcers is their behavior toward cyclists. Anyone who occasionally reads Streetsblog will be able to cite multiple examples in which cops were lenient toward drivers who blocked bike lanes or even ran over pedestrians or doored or hit cyclists (and in one case ran over a pedestrian themselves), and multiple other examples in which they were treated lawful cyclist behavior as illegal or clipped bikes for trumped-up reasons and harassed their owners. All of these examples are from New York except the cop who ran over a pedestrian, who’s from Jersey City. This is a city in which drivers are a minority, and yet they’re considered Us, whereas cyclists are Them: hipsters, radicals, immigrants, Europeans. Not only are cops upholding a set of values rather than the law, but also those aren’t even consensus values.

Different Kinds of Centralization (Hoisted from Comments)

As an addendum to my post about transit cities and centralization, let me explain that the term centralized city really means two different things. One is diffuse centralization throughout the core, typical of pedestrian cities and bus cities and of Paris ex-La Défense; the other is spiky centralization around geographically small transit hubs, for examples Midtown Manhattan, the Chicago Loop, and Central Tokyo. A transit city will tend toward the latter kind of centralization, which is based on walking distance from the subway.

By bus city, I mean a specific kind of urbanism that never existed in the West, but crops up repeatedly elsewhere. It occurs when a city grows too large for walking and cycling while it’s still too poor to build rapid transit, whose construction costs are very high as a share of GDP in developing-world cities. Old buses are not expensive to buy, and their main cost component is labor, which isn’t expensive in a poor city; Beijing for example has only recently gotten rid of conductors on buses.

For a good source on different typologies, I as usual recommend Paul Barter’s thesis – it’s not the main subject of the thesis, but the thesis explains it as background. Bus cities, much like pedestrian cities (which are cities where most people walk to work), tend to be dense all over and monocentric in the sense that there aren’t large suburban centers around them, but they do not have a dominant CBD since buses don’t have the capacity.

Paris is unique among first-world megacities in having preserved this arrangement with its height limits. But it’s still moving in the spiky direction somewhat: the RER has wide stop spacing, which encourages spiky development; and the proposed orbital may be marketed as a circumferential line, but it’s for the most part just a north-south line through La Défense that’s being run together with other lines to potential secondary centers. The difference is that La Défense is more sterile and less pedestrian-friendly than Midtown Manhattan and the Chicago Loop. I may write about this in another post, but greenfield CBDs seem to be always worse for pedestrians than legacy ones, and if the legacy CBD hasn’t evolved to the spiky transit city form, then urbanists may conflate the spiky transit city form with the pedestrian-unfriendliness of the greenfield CBD.

Transit city centralization works differently – it’s based on walking distance from the main rapid transit nodes. Recall that transfers at the downtown end are the most inconvenient for suburban commuters, so that one subway stop away from the center is too far. This makes the transit city CBD inherently geographically small, so that the job density is much higher than that of any other urban form; the job density can also be higher because of the larger amount of space afforded by skyscrapers.

In contrast, the transit city is unlikely to be monocentric. A dominant CBD accessed by rapid transit is a geography that tends to create extremely long commutes – much longer than car-accessible edgeless cities, though not longer than trying to access the same CBD by car – and this leads governments to promote the growth of secondary centers, which are also spiky. Because those secondary centers look like CBDs and not like endless sprawl as do the secondary centers in the US, they make the city look polycentric, even if measured in terms of the CBD’s share of metro area employment they’re very CBD-dominated. When I say a transit city is inherently a centralized city, I do not mean that secondary centers are impossible or undesirable, just that the CBD needs to have a relatively large share of jobs, and that the secondary centers should be actual centers – if they can’t be like Shinjuku, they should be like Jamaica or Newark or how Tysons Corner wants to look in 20 years and not like how Tysons Corner looks now.

For example of how this kind of centralization emerges from the other kind, we can look at the evolution of cities that built large rapid transit networks. Tokyo around Nihonbashi would be the best example, but New York around City Hall is as good. While Lower Manhattan is clearly a smaller CBD than Midtown, it still looks like a spiky CBD, which it did not a hundred years ago. If you plot the locations of the skyscrapers in Lower Manhattan, with few exceptions they’re all south of Chambers, usually far south; peak employment is around Fulton and Wall Streets. The old elevated terminal for Brooklyn trains at Park Row would be inappropriately located. North of Chambers there are city neighborhoods with names like Chinatown or TriBeCa, which are mixed-use enough to have many jobs but have nowhere near the job density of Wall Street.

A related kind of centralization occurs in a multipolar city region, composed of many small cities. None of the cities of the Ruhr is large enough to spawn spiky subcenters on its own, but because the region has grown so interdependent it’s as big as a megacity, the legacy centers in the various cities have turned into a spiky centralization, only without one CBD dominating the rest.

I think it’s the last kind of spiky centralization that transit advocates think of when they propose to turn LA into a multipolar region. Or perhaps it’s in a limbo between a true multipolar region and a unipolar one with well-defined, transit-oriented secondary CBDs. On the one hand, the transit lines proposed in and beyond Measure R are not very downtown-centric. Each direction out of downtown generally gets one line, the exception being the west because of the low-hanging Expo Line fruit and the higher-demand Wilshire corridor. The focus is on connectivity between different poles, since unlike a true transit city Los Angeles has no capacity crunch on its transit system. The subway proposal for going beyond Measure R is to continue south of Wilshire on Vermont, missing downtown entirely, rather than, say, continuing east of Union Station along Whittier.

But on the other hand, the secondary cores are defined in relation to downtown – west (Santa Monica, UCLA), north (Burbank), south (Long Beach), and so on. It’s not like the organic buildup of agglomeration that merged the various cities of the Ruhr into one megaregion, or the merger of the metro areas of New York and Newark, or on a larger scale San Francisco and San Jose. Instead, these secondary cores emerged as secondary to Downtown LA, and only became big because Downtown LA’s transportation capacity is limited by the lack of rapid transit. Put another way, a transit revival in Los Angeles that includes rapid transit construction would make Los Angeles more downtown-oriented rather than less.

A Transit City is a Centralized City

In New York, a large fraction of employment clusters in a rectangle bounded roughly by 59th Street, 2nd Avenue, 42nd Street, and 9th Avenue. Although it’s a commonplace that New York employment is centralized around Manhattan, in reality most of Manhattan is residential, and employment is concentrated in a few square kilometers in the heart of Midtown. This is where the subway lines converge from all directions – elsewhere there simply isn’t enough capacity. Of course it wasn’t always like this: Manhattan’s population in the 1890s was the same as it is today, and it was clustered toward the southern third of the island, but employment was relatively evenly distributed in the downtown area. What has happened since then is that New York became a transit city.

There’s a strong correlation between the form of a city and the mix of transportation options people use. This extends well beyond density, but the principle is the same. Transit is at its best at high intensity, because this is what supports high-frequency service. Cars are the opposite: even on a normal urban street, a car alone will beat any rapid transit line, but every additional car will slow down the road dramatically, so that at even the moderate intensity of an edge city gridlock ensues.

Although usually this principle is stated in terms of density, it’s equally true for work centralization. The pedestrian city and the bus city will be dense all over, and feature high job density scattered across neighborhoods: walking is too slow for the transit city pattern to emerge, and buses have too little capacity. But dedicated rapid transit wants to serve an area right next to the stations, and once a network is built, a CBD grows around the central area. This CBD is typically small, just a few square kilometers. Even vaguely CBD-ish locations, such as Penn Station, are too far, as one commonly quoted figure about work locations demonstrates. The CBD isn’t even large enough to encompass all of the 34h-59th Street strip that the tourist guidebooks define as Midtown. The subway lines only form a tight mesh in a subset of that general area.

The job density of such a CBD is measured in hundreds of thousands per square kilometers, requiring many high-rise towers, several of which are supertall. In contrast, most of New York’s residences are mid-rise, and Tokyo’s are low- and mid-rise; their residential densities in the low tens of thousands per square kilometer are high enough that they are considered the epitome of density, but their CBDs are an order of magnitude denser.

Of the major transit cities of the world, Paris is the only one that’s resisted this trend with its height limit, but instead a transit-like CBD started out in La Défense, and the same pattern that comes from the subway in New York or Tokyo or the L in Chicago emerges with the RER. Of course, Paris maintains very high residential density, but its job distribution is more in line with that of a bus city – employment is dense all over, and the Downtown Paris employment density peak is less pronounced than in comparable transit city downtowns.

This does not mean a transit city needs to have empty trains going in the reverse-peak direction, as Cap’n Transit, Jarrett Walker, and others charge. A transit city will have job destinations outside the CBD, growing around rapid transit junctions: for example, Tokyo has Shinjuku, Shibuya, and Ikebukuro, all of which are so replete with high-rises it’s hard easy to forget they’re secondary job centers. While there is still a pronounced peak direction, people rely on transit so much that they take it for regular errands, supporting very high off-peak frequency by the standards of trains with drivers.

New York has something similar in Downtown Brooklyn, Jamaica, and Long Island City, but the modal split of those job destinations is much less favorable to transit – 50% in Downtown Brooklyn and Long Island City and 30% in Jamaica, according to a study of New York’s secondary job centers that I can no longer find. This is a general feature of many old American cities: the core looks like a transit city, but beyond it is a car-centric city, filled with edge cities and edgeless cities. Because the layout beyond the core is car-centric, the off-peak and reverse-peak traffic that supports high all-day bidirectional frequency on the Tokyo rail network, or for that matter on most New York City Subway lines, does not exist. The preference of American commuter rail agencies for peak-only service comes partly from an operating model that makes it impossible to run frequent off- and reverse-peak service, but also from a job distribution that makes the market for such runs small even under the best industry practice.

A corollary of this fact is that the multipolarity of other cities, for example Los Angeles, is not an asset. It would be an asset if those job centers were intense and could be easily served by transit; in reality, they have moderate intensity, nothing like that of the secondary centers of Tokyo or even New York, and serving many of them requires digging new subway lines. Burbank, on the legacy Metrolink network, could make a reasonable site for a transit-oriented secondary center, if commuter rail operations were modernized and local transit lines were extended to it; the Westside and Santa Monica do not, and the hope is that the investment in the Subway to the Sea could enable them to grow to reasonable size.

The key here is that the reason Shinjuku, Ikebukuro, and Shibuya are as transit-oriented as Central Tokyo is that they historically arose as connection points between the Yamanote Line and the private railroads. In particular, they already had rapid transit fanning out from multiple directions when they became major job centers. But Tokyo’s transit development history is peculiar; most other cities did not have large electrified rapid transit systems terminating at the edge of the urban core prior to building local subway lines.

A second corollary then is a strategy that sought to make New York a more transit-oriented city would treat centralization differently. It should turn the secondary centers into transit nodes in their own right, with tails extending as far out as reasonably possible. Jamaica already has some of the infrastructure, but it’s used poorly because of antiquated LIRR practices; the same can’t be said of Flushing, so a priority should be to build reasonable-quality transit from multiple directions, connecting Flushing with College Point and Jamaica and modernizing the LIRR so that it could connect it with Bayside.

A point that many people writing about this neglect (with pleasant exceptions like Cap’n Transit, the Streetsblog crowd, and Paul Barter) is that this requires both the carrot of more transit and the stick of less parking. In any case it’s hard to create high job densities when much of the land is used for parking. But on top of that parking mandates make it difficult for transit to be competitive when it’s expected to include railyards and depots in its budget and roads are not.

But what a transit city doesn’t need is job dispersal. The importance of creating secondary centers is strictly as alternatives to auto-oriented edge cities and edgeless cities, since whatever happens, not all jobs will be in the CBD. A large city with rapid transit connecting to all major neighborhoods will automatically have high transportation capacity. Rapid transit is good at transporting tens of thousands of people in one direction in the peak hour; let it do what it’s good at.

New York-New Rochelle Metro-North-HSR Compatibility

Let me preface this post by saying that there should not be any high-speed trains between New York and New Rochelle, except perhaps right at the northern end of the segment. However, to provide reasonable speeds from New York to Boston, it’s desirable to upgrade the maximum speed between New York and New Rochelle to 200 km/h or not much less. The subject of this post is how this can be accommodated while also permitting some regional rail service, as proposed by the MTA. There are two reasons to bundle the two. First, some of the work required could be shared: for example, new stations could be done at the same time as rail and tie replacement. And second, the presence of both upgraded intercity rail and regional rail on the line requires some four-tracking and schedule optimization.

The physical infrastructure required for boosting speeds within New York City is fairly minimal by itself. The right-of-way in the Bronx has some curves but they are not very sharp and can be somewhat straightened without knocking down buildings, and even the curves in Queens and on the Hell Gate Bridge, while unfixable without major viaduct modification, are not terrible if superelevation is high and tilting is enabled.

A big question mark is what the maximum speed permitted by the physical layout of the East River Tunnels is. Current speed is 97 km/h (60 mph), but top speed today in other sections of the network are below those achieved decades ago (for example on Portal Bridge), and trains with specially designed noses, as the Shinkansen rolling stock is, could potentially go even faster. Regardless, it is not important for HSR-regional rail integration, since the East River Tunnels have no stops and will be running far under capacity once East Side Access opens. Thus, all travel times in this post are between New Rochelle and Sunnyside Junction, which is notionally considered to be located at 39th Street. This is a 25-kilometer segment.

Another question mark is what the speed limit on the S-curve south of New Rochelle is. Currently the limit is 48 km/h (30 mph). Raising it requires grade-separating the junction between the NEC and the current New Haven Line. It can be raised further via curve straightening, but the question is how much eminent domain can be done. The maximum radius that can be achieved with minimal or no eminent domain is 700-800 meters. Some further eminent domain may be required to have this curve start far enough from the southbound platform that full 200 mm superelevation is achievable without subjecting local train riders to too much cant excess. For comparison, slicing through New Rochelle and the Pelham Country Club allows essentially eliminating the curve and allowing maximum speed through the area, which taking surrounding curves into consideration is about 240 km/h.

Assuming 150 km/h (about 700 meters radius, 200 mm cant, and 175 mm cant deficiency), the technical travel time for a nonstop intercity train between when it passes New Rochelle and when it passes Sunnyside is about 9 minutes; this includes slowdowns in Queens and the Bronx and on Hell Gate. A nonstop M8 with a top speed of 145 km/h would do the same trip in about 11:15. (Amtrak’s current travel time from New York to New Rochelle is about 25 minutes, of which by my observation riding Regional trains 6 are south of Sunnyside.)

Even the above travel time figures require some four-tracking, independently of capacity, in order to limit cant excess. Unlike the Providence Line, the Hell Gate line has some curves right at potential station locations – for example, the Hunts Point stop is located very close to the curve around the Bruckner Expressway, and the Morris Park stop is located in the middle of a curve. The Bruckner curve radius is about 500 meters, and 200 mm superelevation would impose 80 mm cant excess on even a fast-accelerating commuter train (1 m/s^2 to 72 km/h), and an uncomfortable 140 mm on a slower-accelerating one (0.5 m/s^2 to 51 km/h). The Morris Park curve is even worse, since it would impose a full 200 mm cant excess on a stopped train. So we should assume four-tracking at least at the Morris Park station, which is located in the middle of a curve, and Hunts Points, and potentially also at Parkchester.

Now, a local train would be stopping at New Rochelle and four stops in the Bronx, and should be stopping at Sunnyside. Although a FLIRT loses only about 75 seconds from a stop in 160 km/h territory, assuming 30-second dwell times, the M8 is a heavier, slower-accelerating train, and for our purposes we should assume a 90-second stop penalty. This means that, counting New Rochelle and Sunnyside together as a single dwell-free stop (they involve one acceleration and one deceleration in the Sunnyside-New Rochelle segment), local technical travel time is 18:15, about the same as what Amtrak achieves today without stops but with less superelevaiton and inferior rolling stock.

Now, 18:15-9 = 9:15, 9:15 times the schedule pad factor is 9:54, and modern signaling allows 2-minute headways up to 200 km/h; thus we can accommodate 4 tph intercity and 4 tph local Metro-North without overtakes except at New Rochelle and Sunnyside.

There is only one problem with the no-overtake scenario: the MTA plans on a peak traffic much higher than 4 tph, in line with the New Haven Line’s high demand. It’s planning on a peak of 6-8 tph according to what I’ve read in comments on Second Avenue Sagas. This naturally breaks into 4 tph that make local stops and 4 that do not (though my suspicion of MTA practice is that it wants fewer than 4 local tph); if there are fewer than 8 trains, one slot could be eliminated.

Let’s look then at a 4/4/4 scenario. Assume that trains depart Sunnyside in order of speed – HSR first (passing rather than stopping at Sunnyside), then express Metro-North, then local Metro-North. A local train will be overtaken first by the following HSR, and then by the following express. If we could move the overtake point to New Rochelle, the local would not need to wait for trains to pass it. In reality, 4/4/4 means the local departs Sunnyside 4-5 minutes after the HSR train passes it, and has 9 minutes of time penalty before being overtaken again. If the stop penalty could be reduced to 75 seconds, then the overtake could be moved to New Rochelle, demonstrating the use of top-quality rolling stock. But the M8s are good enough for many purposes, and therefore we will not assume a noncompliant replacement, unlike in the case of the MBTA, whose rolling stock is slow and very heavy.

With 9 minutes of time to make up, it’s tempting to have an overtake at a four-tracked Co-op City station. But then the local would have to be overtaken by two trains in a row, and moreover the two trains would become quite separated by then due to differing top speeds, and this would force a penalty on the order of 6 minutes.

I claim that the best would be to four-track a segment between two or even three stations; the right-of-way is wide enough anyway. In addition, the Morris Park curve could be straightened if the Eastchester Avenue overpass were modified, and doing this in conjunction with four-tracking would be cheaper than doing each alone. Under this option, the local would leave Sunnyside much later than 2 minutes after the express, just enough to be overtaken by HSR at Morris Park. It would then keep going to Co-op City until overtaken by an express. This would essentially save about 2.5 minutes out of the 6 in penalty, since the train would be in motion for that time.