Category: Urban Transit
Improving the MBTA: Electronics and Concrete
Where improvements in New York and other very large cities can easily include multiple new subway lines, the same is not true of Boston. The concrete pouring would be wasted, since Boston’s existing subway lines are not at capacity. The busiest line, the Red Line, has a peak frequency of one train every 4.5 minutes, which could be doubled with appropriate signaling improvements and more rolling stock if necessary. The Green Line has bigger issues coming from branching – its core segment already runs close to 40 trains per hour – but this could be resolved by obtaining fully low-floor vehicles and lengthening trains to allow one or two extra branches.
Another thing that Boston lacks and other US cities do is very busy bus lines to railstitute. Boston’s busiest bus line is the Silver Line to Dudley Square, which used to be the southern part of the Orange Line and should be light rail; unfortunately, the MBTA rejected it as cost-ineffective (see pp. 36-7) by applying a wrong cost-per-rider metric, as I will explain in a later post. But beyond that, the list of bus lines (p. 50 of the Bluebook) doesn’t contain anything nearly as juicy as New York’s bus lines: New York’s 50th busiest bus is roughly even with Boston’s top bus at 15,000 weekday riders, and its top routes have 50,000, making them obvious choices for subway extensions.
Since Boston does not have a capacity problem requiring more concrete pouring on its subway lines, nor high-productivity buses to railstitute, concrete pouring should focus on the other main reason to build rapid transit: to extend service to areas that do not have it. That’s the main reason to build the North-South Rail Link: it’s as much about direct service from suburbs north of Boston to downtown and maybe Back Bay as about rationalizing service and permitting through-running. As in Philadelphia and as should be the case in New York, through-running is primarily not about suburb-to-suburb service, but about access to job centers near the stations of the other half of the commuter network (in New York those would be at Newark, Brooklyn, and Jamaica; in Philadelphia, at Temple and 30th Street Station and in University City).
The list of concrete-pouring, lines-on-a-map extensions of the MBTA in or near Boston should therefore be limited to required Big Dig mitigations, and not much more. This is not just because they are legally mandated. They are also good transit by themselves – the North-South Rail Link for the aforementioned reasons, the Assembly Square stop on the Orange Line because of the TOD potential, the Red-Blue connection because of the East Boston-Cambridge service need, and the Green Line extensions because they provide much-needed transit service in Somerville that would otherwise need to be picked up by commuter rail, at the cost of good intercity service on the Lowell Line. Apart from these, the only major radial extension that should be pursued is the dismembering of the Needham Line outlined in my last post, in which the Orange Line would take over the portion within Boston and the Green Line would take over the portion in Needham.
What should be done instead of more expansive extension plans is very aggressive use of electronics to make regional rail more useful, recalling that its share of the suburbs-to-Boston market is about one third. This necessitates a lot of concrete pouring as well – on high platforms, on track repairs, on double-tracking some single-track segments, and on other things that do not show up easily on maps – but much less than adding tunnels.
The one difficult bit of concrete pouring that has to be done, in conjunction with the North-South Rail Link, is grade-separating the junctions that lead up to North and South Stations. Without the rail link, the South Station throat is such that, run right, it’s operationally at least two stations (one for lines serving Back Bay, one for the rest), and as many as four (Worcester, the lines feeding into Ruggles, Fairmount, and Old Colony and Greenbush); this allows for zero-conflict moves, higher capacity than the MBTA thinks, and a system in which delays on one line do not affect the others. With the rail link, those two to four systems need to feed into one track pair in a way that avoids opposite-direction flat junctions. The need for grade separations right in the station throats would add substantially to the cost of the rail link over a simple two-track tunnel; that’s why I’m not instantly dismissing it as something that at normal-world costs would take a relatively trivial $500 million.
Despite the rail link’s cost, the electronics are themselves substantial. Signaling improvements are also required, to enable tighter overtakes. Moreover, full electrification should be non-negotiable – the MBTA’s stop spacing may not be as close as that of Metra or the LIRR or Metro-North or SEPTA, but it’s short enough that electrification would make a significant difference in performance. It also interacts interestingly with FRA waivers: on the one hand, without electrification, there are no good FRA-compliant trains – the Colorado Railcar DMUs have mediocre performance and are expensive and vendor-locked, and locomotive-hauled trains have terrible performance. With electrification, there exist decent FRA-compliant trains, but there also exist very good noncompliant trains. According to the Fairmount Line DMU document, current trains have a total acceleration-only penalty of 70 seconds to 60 mph, and Colorado Railcars shave that to 41 (see chart on p. 10); judging by timetable differences and dwell times, the best compliant EMUs lose about 20-25, and judging by YouTube videos FLIRTs lose 13.
The timetable examples I’ve put out – for the Providence Line in past posts, and for the Lowell Line in comments – are very ambitious, and require the signaling, electrification, and rolling stock to be perfect. The costs are not very high by US standards, but are nontrivial. Electrification costs a little more than a million dollars per kilometer (or about $2 million per mile), though it’s unclear whether this is based on route-km or track-km, as one citation I have is for a single-track line and another does not make it clear which one is under consideration. The cost is thus either about $750 million or about $1.5 billion, exclusive of rolling stock. But the benefit is commuter trains that can beat the freeways while also providing adequate regional service and connect to urban rail.
Improving the MBTA: Regional vs. Intercity Service
The MBTA commuter rail lines are laid in such a way that there’s an inherent tension between providing local service and providing longer-distance intercity service. It’s less apparent on the Providence Line because the intercity component, i.e. Boston-Providence, follows immediately just from serving the suburbs between Boston and Providence, but elsewhere there are greater problems. Good local service would have intense frequency in the inner portions of commuter lines; unfortunately, most lines only meet right next to the termini, reducing the opportunities to use interlining to create high-frequency inner segments.
Good local service also needs many infill stops, while good intercity service needs higher speeds. My proposals for the Providence Line essentially go with intercity service needs, justified by the facts that Providence is a major anchor, that high top speeds are possible on the line, and that the line should also host high-speed trains. Fortunately, the Providence Line has an opportunity for more intense local service using the Stoughton Line to add frequency; while this would end up overserving Canton Junction and Route 128, Readville and points north would get adequate peak service, and acceptable off-peak service. This is not as true on other lines, especially on the North Side, in which there’s a tradeoff between fast service to outlying cities and good service within Cambridge and Somerville.
Of course, the issues I’ve focused on in my previous post on the subject – electrification, high platforms, modern rolling stock – are useful for both. A fast-accelerating EMU could connect Boston with the various terminals at the same time as today’s express trains while making all stops as well as some extra infill stops. The problem comes from trying to fit trains into a clockface schedule. On a few lines, for example the Lowell Line, it’s actually easier to close very lightly used stations (Mishawum) or stations that are very close to other stations (Wedgemere).
Another issue is outbound extensions. With some, there’s so little traffic beyond the current terminus, or sometimes even beyond a point slightly closer than the current terminus, that the decision should be easy. This contrasts with the MBTA’s approach of proposing more and more outer extensions. With others, the intercity functions make extensions more reasonable, within certain bounds. I believe the following list of judgment calls would be reasonable:
1. Providence Line: no extension required – the line’s natural end is Providence. If Rhode Island wants to provide a low-frequency glorified parking shuttle from Wickford Junction and the airport to Providence, it’s its business, as long as it doesn’t muck up timetabling that’s based on Providence-Boston service.
2. Stoughton Line: an extension to Taunton would work, and possibly even to New Bedford. I’m iffier on Fall River, which has stronger commute ties to Providence; however, Providence-Fall River requires too much new infrastructure to be easy.
3. Franklin Line: either extend it to Milford (which may be easier to serve from the Worcester Line), or cut it back to Franklin. The Forge Park terminus is close to a lot of office park jobs, but the local road network is so sprawled out that it’s not worth the extra few minutes of travel time.
4. Fairmount Line: building infill stations is an excellent idea, though it should be coupled with increase in frequency and service level to make them more useful. One way to improve off-peak frequency is to route all Franklin Line trains along this line, and perhaps add supplementary trains that turn at Readville. The advantage of this is that the Fraknlin and Fairmount Lines used to be one railroad, with a grade-separated crossing over the Providence Line; in contrast, the junction at Readville is flat, making it more operationally cumbersome to have trains cross from one line to the other.
5. Needham Line: no extension necessary – the only possibilities would dismember the line in favor of much lower-density suburbs than Needham. Better would be to eliminate the line entirely and put Needham on a branch of the Green Line, and restore past plans to extend the Orange Line to West Roxbury. This would dismember the line too, but in favor of more service to dense areas rather than less. I don’t know what’s Needham’s commute tie to West Roxbury, but its commute tie to Newton and Brookline is fairly strong, 1,300 vs. 3,400 to Boston and another 3,400 in-town.
6. Worcester Line: Worcester is the natural terminus, so no extension should be entertained.
7. Greenbush Line: Greenbush is the natural terminus. The greatest urbanization is on the coast rather than along the railroad, and this limits the line’s usefulness.
8. Kingston/Plymouth Line: the natural terminus is downtown Plymouth, slightly farther out from the current Plymouth station, which should be renamed North Plymouth or just closed for lack of utility. In addition, Plymouth sends Boston 2,565 commuters, and Kingston only 797. Either the roles of Kingston and Plymouth should be switched – Plymouth would get served all day and Kingston would get only supplemental rush hour trains – or the Kingston branch should be closed, and replaced with a station on the main line.
9. Middleborough Line: for ordinary regional traffic, the line should be marginally cut back, to place the Middleborough station at the center of the town. In fact, there’s a dropoff in commute volume south of Brockton, and yet another south of Bridgewater; Middleborough is a fine terminus, but is not a proper anchor like Providence, Worcester, or especially Plymouth. On the other hand, there’s some potential for intercity traffic to Cape Cod, capturing some commuters as well as vacationers heading the other way.
10. Fitchburg Line: the MBTA’s proposed extension to Gardner looks weak to me, though not completely daft. That entire region of northern Worcester County has much stronger commute tie to Worcester than to Boston, in similar vein to the issue of Fall River’s connection to Providence. The commute tie to Framingham, as in the MBTA plan to have a branch leaving Framingham toward Leominster, is even weaker than that to Boston. It would be better to have a regional line connecting Gardner to Worcester, which would also have the advantage of taking a much more direct route than the freeway network; connecting Fitchburg and Leominster would require more work and compete with I-190 directly.
11. Lowell Line: here an outbound extension is natural and desirable, since Nashua and Manchester have a nontrivial commute tie to Boston and are significant cities in themselves, though as with Cape Cod this would be more of an intercity line. New Hampshire had a plan for such an extension, but it was killed by state Republicans early last year. This is unfortunate, since Nashua in particular has a less than great freeway connection to Boston, which a fast electric train could consistently beat.
12. Haverhill Line: Haverhill is a natural terminus. Although Rockingham County has a strong commute tie to Boston, the greatest part of it comes from very sprawled out towns near I-93, far from the line.
13. Newburyport/Rockport Line: the split at Salem allows natural interlining to give the towns with the strongest commute ties the most frequency. An additional branch to Marblehead would be prudent, providing even more frequency to Lynn, Chelsea, and additional infill stops in Revere. At the north end, Portsmouth looks like a fine intercity terminus, but in fact that part of Rockingham County is a marginal commute market to Boston, better than that feeding into Haverhill but much worse than the I-93 sprawl.
Not discussed above are station placement and infill stations. Station placement is relatively easy, since bad cases like Westborough and the aforementioned Middleborough and Kingston look obvious on a map. In addition, such office park stations with terrible ridership as Mishawum and River Works are already treated as such, so almost all trains skip them and their ridership is very low, making them clear candidates for closure.
Infill stations are harder. The problem is that on the North Side, the four lines split too early. This means that, while infill stations are possible, it’s hard to give them adequate frequency. Short-turning local trains could help somewhat, but is the most difficult on the two lines that serve Cambridge and Somerville, the Lowell and Fitchburg Lines. It’d be much easier to do this with Lynn (which already benefits from interlining and would benefit even more from a Marblehead branch) or Malden (which has the Orange Line).
That said, the Lowell Line might be able to support a local train to Winchester and an intercity train that makes zero or one intermediate stop between North Station and Winchester. The commute market is not great at this distance, though; Belmont has 3,100 Boston-bound commuters, and 290 inbound riders at its two commuter rail stations. A reroute of the Fitchburg Line along the Charles River Branch through Watertown might get more ridership; it would be slower, but it has zero intercity function, compared with strong potential at and east of Brandeis. To succeed, high frequency and short station spacing are required. For an example using the Charles River Branch, see here.
On the South Side, the Worcester Line begs for infill between Yawkey and Newtonville, but some of the people it would serve may already be riding the Green Line. The Green Line doesn’t perfectly parallel the line the way the Red Line parallels the Old Colony Line or the Orange Line parallels the Providence Line and the Haverhill Line, though, and there’s room for two or three stations serving Allston, Brighton, and Nonantum. On the other hand, some of these stations would compete with Watertown somewhat, and are less ideally placed in that the Worcester Line has an intercity function whereas the Fitchburg Line doesn’t.
Finally, another unmentioned issue is the effect of rapid transit extensions, especially of the Green Line. The extension plan to Somerville, which the state is obliged to build as one of many mitigations for the traffic induced by the Big Dig, is effectively a replacement for Lowell Line infill in Cambridge and Somerville; the line would only really need one infill stop to connect to the Green Line, and perhaps the Green Line would need to be extended to West Medford, if not to Winchester. That said, the interaction with rapid transit is more complex than this, and I will discuss it more in a future post.
Improving the MBTA
The MBTA has a problem. And I say this coming from New York, whose standards for good regional transit aren’t all that high, but now Metro-North looks like something to look up to from the MBTA. Ridership on the system is rising, but not very quickly; the MBTA moreover has no plans to modernize. Most of what I’m going to suggest will involve commuter rail, not because it’s the most important portion of Boston’s public transportation but because it’s the part I’m most familiar with and also the part that seems most direly in need of improvements. Put another way, I’m necessarily going to talk about the MBTA as perceived from Providence, rather than from within Boston.
The main difference with New York and past proposals for improvements, both subway extensions and regional rail, is size, and scope. In New York, practically everyone who works in Manhattan takes public transportation or walks. The transit mode share to Boston is lower and the car mode share is much higher. This seems especially true for people commuting from north of Boston.
The main prescriptions will not surprise people who have read my posts on best industry practices. In short, the MBTA commuter rail needs to do the following:
– Full electrification, starting from running EMUs rather than diesels under the catenary on the Providence Line, but also extending to all other lines.
– Level boarding along the entirety of all platforms, rather than just one car length, in order to shorten dwell times to no more than 30 seconds at outlying stations.
– Higher-quality rolling stock, with better-configured doors than the present cars as discussed in a DMU conversion study; all new EMUs available, both FRA-compliant and noncompliant, would be fine, though noncompliant trains with a waiver would have somewhat better performance and lower operating costs.
– Reasonable frequency all-day on a simple clockface schedule: ideally, all branches should have 4 trains per hour at the peak and 2 off-peak – the lowest-ridership lines tend to be the shortest-distance, for which frequency matters the most, whereas the highest-ridership lines (Providence, Worcester) are practically intercity, the higher demand balancing out a lesser need for frequency.
– A fare union with local buses and the subway, so that commuter train tickets are automatically valid without extra pay.
– Relocation of stations to walkable urban areas, away from park-and-rides that only serve to extend the suburbs into Boston rather than extending Boston into the suburbs.
– An end to outbound extensions, such as the ongoing project to extend the Providence Line to Wickford Junction, and instead a shift toward infill stations, especially in underserved Cambridge and Somerville.
In the longer term, a North-South Rail Link is unavoidable – North Station is too far from the CBD, some through-service from south of Boston toward Cambridge is advisable, and the rail link as proposed would give a direct connection to the Blue Line and thus to East Boston and the airport. Although the official cost estimate is $9 billion, for barely 2 kilometers of tunnel and associated connections, such an estimate would make the project more expensive km-per-km than any other I know of except perhaps East Side Access, and a more honest attempt at cost estimation yielded $3-4 billion, on a par with outsized American subway construction costs; at European costs, it would be less than a billion. Observe that electrification could reduce the cost by allowing steeper grades; the official proposal still uses heavy diesel locomotives. In either case, this is far more expensive than the points above; concrete costs much more than organization and electronics.
Let me now explain in more detail what’s happening in and around Boston – more precisely, what is wrong, and potentially what ridership level should be expected of good regional rail.
The main datasets I’ll be working with are the American Community Survey as of 2009, the town-to-town commuter flows as of the 2000 census, and the MBTA Blue Book, offering ridership numbers as of 2009 and going back to 1989. Bear in mind that most data from the 2009 ACS will be scrubbed from the net on January 20th, giving us only 2010 census-based numbers, which undercount immigrants and the poor and thus undercount cities; however, while the 2010 census gets magnitudes of change wrong, it’s very close in terms of absolute populations, absolute mode shares, etc. All numbers I cite here are from the 2009 ACS; you can verify that a source exists now, but not beginning a week from now.
The current background trends to observe are:
– Boston’s population is increasing, quickly. The 2000 estimate base, using a 2010 backdate that also depresses intercensal estimates to fit the 2010 undercount, was 692,745 for Suffolk County, which contains Boston and three small inner suburbs. By 2009, the county’s population was 753,580, a growth of 8.8%. Boston itself had 9.5% growth from the 2000 census, which is not directly comparable to the ACS and the estimate base but is extremely close in numbers. The metro area grew only about 4.5% over 2000 – a little less if one takes the full Combined Statistical Area, which includes slow-growing satellite metros like Providence.
– Transit ridership has grown in the last 10 and 20 years, but by much less than in New York. The Red Line’s grown 50% in the last 20 years, but the other T lines barely grew. The commuter rail grew quickly as lines were put into service in the 1990s, but had little growth in the 2000s, despite high gas prices.
– The Silver Line BRT is very underused, despite the promise and branding as rapid transit on tires. Even for airport service, where the Silver Line gets to the terminals, it gets less than half the ridership of the Blue Line (2,600 vs. 6,900), which only serves a station connected to the terminals by free shuttle buses. The Washington Street branches (SL4, SL5) are more frequented, but their combined ridership is only about the same as that of a single subway station, and are just bus-plus.
– Boston is the opposite of a bedroom community – it has 520,000 jobs vs. 278,000 employed residents, all as of 2000. This 1.87 ratio is much higher than that of New York (1.18), which contains most of its bedroom communities, and is more comparable to that of Manhattan (2.75). The same is true of Cambridge, with 114,000 jobs and 55,000 employed residents, for a ratio of 2.08.
– Unlike New York, both Boston and Cambridge draw substantial numbers of commuters from suburbs outside urban transit range – Boston draws about 200,000, and Cambridge draws about 55,000. Inbound commuter rail ridership on the MBTA is 70,000. Cambridge is a lost cause under current operating paradigms – it has no stations, and if it did they’d be too poorly integrated with the top two employers.
– Total transit vs. car mode share is 26-52 for people working in Cambridge and 37-50 for people working in Boston; the corresponding numbers are 56-29 in New York (including bedroom communities like Queens) and 73-14 in Manhattan (which is more comparable to Boston in terms of workplace geography).
– There are about equally many suburban commuters into Boston from the north as from the south. People driving to the edges of the Orange and Red Lines cannot make too big a difference (Alewife has 2,700 parking spots, and Malden and Oak Grove have just under 1,000 between them), so the difference seems to be that more people are commuting into South Station than into North Station. Observe that South Station is right next to the Boston CBD, whereas North Station is a little farther out.
– Boston has built too much highway infrastructure for a kernel of a transit-oriented edge city to exist along Route 128 as it does in Stamford. 10% of people who work in Stamford take transit to work. There aren’t numbers for all edge cities near Boston, but where they exist, they’re much lower, e.g. 2% in Burlington. Furthermore, since Route 128 exists and is continually upgraded, there’s not much hope of serving these centers by commuter rail from suburbs on the opposite side of Boston.
The upshot of all this is that there’s room to more than triple MBTA commuter rail ridership, while also maintaining healthy urban rail ridership coming from population growth in Boston itself. However, this requires very good service from the suburbs to the city, and the MBTA isn’t providing it. The problem is that the MBTA relies too much on cars: Middleborough and SouthWestborough are particularly egregious for their poorly located stations, chosen for drivers’ convenience rather than for that of transit users. Even worse, Plymouth, a city that’s older than Boston, gets few trains, while most trains serving the Plymouth Line instead stop at a park-and-ride nearby, at Route 3.
Although the focus of all suburban rail is service to the urban core, this can only be done by treating it as longer-range, lower-frequency rapid transit, rather than by treating it as shuttles from parking lots to the CBD (or almost the CBD, in North Station’s case). People won’t use the trains if they’re too infrequent past rush hour; it’s not 1960 anymore, and people do not always work 9-to-5.
For an example of what the MBTA is doing wrong, let’s look at commuter flows in Rhode Island. There are 4,700 people living in Rhode Island working in Boston. The biggest single source of Boston-bound commuters is Providence, with 1,100; Providence Station has 2,000 inbound weekday riders, so it also draws people from some nearby suburbs – but not too many people. Cranston and Warwick have 700 between them – and they’re getting an airport stop with a very small number of trains. Even Washington County, with 170 commuters, is getting a station. Those two stations cost $336 million between them. Meanwhile, Pawtucket, with 600 commuters plus another 800 in suburbs to its northwest and in Woonsocket, is not getting an infill station.
I hope to discuss concrete schedules, possible changes to station placement, and ways to keep operating costs under control in a future post. For now all I’ll note is that the MBTA needs to stop pushing for extensions far out into suburbia. It’s not going to get ridership out of 9 roundtrips per weekday with a 5-hour service gap, which is what the T. F. Green Airport station gets. It’s going to get it out of reliable, frequent all-day service.
Staten Island Rapid Transit
The great missing piece of New York’s rail network, and the most controversial of any of my proposals, is Staten Island. Connected to New Jersey by the B&O but not toward Manhattan, it relies on buses to the subway and the ferry for its connection to jobs in the rest of New York. Unsurprisingly, this is too slow and low-capacity for the full benefit of rapid transit to emerge, and the borough’s character remains suburban.
Plenty of railfans and transit supporters believe that the subway should be extended from Bay Ridge to Staten Island across the Narrows; the Fourth Avenue Line contains some landside infrastructure preparing for such an extension. While this is one of the options that should be studied, it suffers in two ways: first, the Narrows are the deepest part of New York Harbor, at about 25 meters (83 ft.), and second, the Staten Island end would be at Grasmere, a low-density area.
In contrast, according to the nautical chart, paths that go from St. George to any point between Manhattan and the Bay Ridge freight terminal are at the deepest 16 meters (53 ft.) below mean low water. In addition, the North Shore is the densest and most densifiable part of the borough, and would get better service; the South Shore would get about the same amount of service no matter where east of the Narrows the tunnel landed, but is the less important part of the borough to connect.
I contend that the list of options is as depicted on this map. The main choice is between a direct route and a route that goes through Brooklyn, trading off speed versus intermediate stops and possibly cost. Observe that it is much easier for a line that detours through Brooklyn to serve Downtown Brooklyn at Borough Hall than at the existing train station; this provides some justification for adding a Borough Hall station to a New Jersey-Brooklyn regional rail tunnel.
Not depicted on the map is the interaction of the various alignments with Harbor geology. If the primary factor is minimizing tunnel depth, then there are two options, one more easterly, near or under Governor’s Island or even farther east, and one more westerly, near the mouth of the Hudson. The westerly option opens the possibility for an east-west alignment through Manhattan that goes the “wrong way” – that is, has the Uptown direction pointing in the same direction as the Brooklyn-bound direction of the New Jersey-Brooklyn tunnel. This would give a cross-platform transfer from Staten Island to Brooklyn, which is lacking from the standard direct option.
Another issue is a South Ferry stop. As discussed in my post about the Lower Manhattan station siting, a South Ferry station becomes necessary if the main Lower Manhattan station is too far north, roughly north of Fulton Street. Even if the station is at or marginally south of Fulton, a second Lower Manhattan station could help reduce dwell times at the main station, increasing capacity.
A related issue is keeping all traffic that doesn’t need to be in Manhattan out of the main station. The Staten Island-Brooklyn transfer hogs passenger circulation space. It’s bad enough that a greenfield 100 km/h regional rail tunnel would get people from Atlantic/Pacific to Grand Central in about 11 minutes plus transfer time, versus about 20 on the 4/5, which make more or less the same stops, adding cross-platform transfers. A relief station at South Ferry, or Borough Hall, would go a long way toward mitigating this. (Observe that in the service patterns I’ve proposed for the lines that converge on Midtown, the main transfer points are Secaucus and Sunnyside, avoiding Penn Station.)
For the options that detour through Brooklyn, the choice of neighborhoods to serve and the choice of how much land versus sea tunneling both give rise to several options. One option would serve Red Hook, connecting it either directly to Manhattan or via Borough Hall, giving it a rapid transit connection it currently lacks. Offering new rapid transit service to neighborhoods that lack it is always a positive, and could also get very good ridership: for a similar example, the MTA’s ridership model for New Rochelle-Penn Station commuter rail service was bullish about the potential of a Co-op City station.
A separate choice is regional rail versus subway. A subway alignment’s main advantage is that it requires less tunneling, just enough to hook the Staten Island Railway into the Fourth Avenue Line. The main disadvantages are that it’s slower than express regional rail, and that the southern Brooklyn subways already suffer from excessive branching and middling frequency.
From the start, the BMT had a problem with merging eight tracks to six, with suboptimal junctions. The Chrystie Street Connection did not change this – it merely allowed all six tracks (the four Broadway Line tracks and the two express Sixth Avenue Line tracks) to serve Midtown. On top of this, Manhattan-Coney Island is not as thick a market as it used to be; with today’s usage patterns, nobody would think to build four different routes to Coney Island plus one to Bay Ridge while leaving Utica unserved and Nostrand a short stub. Additional branching would cut into the frequency of existing lines, worsening service to existing middle-density neighborhoods in southern Brooklyn. Thus, a regional rail option, if it’s at all affordable, would provide much better service. Even the option of connecting the new line to the 59th Street station in Sunset Park would be preserved if the line followed the Gowanus Expressway.
For a few numbers: the proposed cost of the Cross-Harbor Tunnel is $7.4 billion for the double-tracked option; the length and geology are comparable to Staten Island-Manhattan. As of 2000, the total commute market from Staten Island to Manhattan is 53,000 people, i.e. 106,000 trips; additional travel to Brooklyn is 29,000 people, and travel to points north and east of Manhattan is 8,000. Cutting one to two transfers and about twenty minutes from each one-way trip could ensure nearly 100% mode share for travel to Manhattan, as well as a significant mode share to other parts of the city.
Moreover, a zoning deal raising density in St. George and right next to the train station could raise the size of the commute market, adding to ridership. While Staten Island is not particularly pro-development, and has engaged in downzoning recently, a deal in which Staten Islanders get their commute improved so much in exchange for accepting change to their neighborhood could be acceptable. Tellingly, for the North Shore Branch reactivation, the people near the line seem more interested in the higher-intensity options: rail over bus, and possibly heavy rail rather than light rail. NIMBY attitudes are reduced when the change in question is bundled with solving a known local problem, in this case very long commutes.
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.
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.
Transfer Penalty Followup
My previous post‘s invocation of Reinhard Clever’s lit review of transfer penalties was roundly criticized on Skyscraper City Page for failing to take into account special factors of the case study. Some of the criticism is just plain mad (people don’t transfer from the Erie Lines to the NEC because trains don’t terminate at Secaucus the way they do at Jamaica?), but some is interesting:
This is what the paper says:
Go Transit commuter rail in Toronto provides a good example for Hutchinson’s findings. In spite of being directly connected to one of the most efficient subway systems in North America, Go’s ridership potential is limited to the number of work locations within an approximately 700 m radius around the main railroad station. Most of the literature points to the fact that the ridership already drops off dramatically beyond 400 m. This phenomenon is generally referred to as the “Quarter Mile Rule.”
Let’s look at WHY that is. If you live North of downtown and work North of about Dundas Street, it is probably faster for you to take the subway to work. So people aren’t avoid the commuter train because it imposes a transfer, but just because the subway is faster. Same thing if you live along the Bloor-Danforth line. Toronto’s subway runs at about the same average speed as NYC’s express trains. If one lives east or west of the city along the lakeshore, they are going to take the GO Train to Union Station and transfer to the subway to reach areas north of Dundas. I really doubt these people are actually “avoiding” the GO Train, though if there is evidence to the contrary I’d like to see it.
Toronto also has higher subway fares than NYC.
The issue is whether the subway and commuter rail in Toronto are substitutes for each other. My instinct is to say no: on each GO Transit line, only the first 1-3 stations out of Union Station are in the same general area served by the subway, and those are usually at the outer end of the subway, giving GO an advantage on time. Although the Toronto subway is fast for the station spacing, it’s only on a par with the slower express trains in New York; on the TTC trip planner the average speed on both main subway lines is about 32 km/h at rush hour and 35 km/h at night.
Unfortunately I don’t know about GO Transit usage beyond that. My attempt to look for ridership by station only yielded ridership by line, which doesn’t say much about where those riders are coming from, much less potential riders allegedly deterred by the transfer at Union Station. So I yield the floor to Torontonians who wish to chime in.
Update: a kind reader sent me internal numbers. The busiest stations other than Union Station are the suburban stations on the Lakeshore lines, led by Oakville, Clarkson, and Pickering; the stations within Toronto, especially subway-competitive ones such as Kipling, Oriole, and Kennedy, are among the least busy. Some explanations: the subway is cheaper, and (much) more frequent; Toronto’s GO stations have no bus service substituting rail service in the off-peak, whereas the suburban stations do; Toronto’s stations have little parking.
Why the 7 to Secaucus Won’t Work
Bloomberg’s expressed support for the now $10-billion proposal to send the subway to Secaucus is generating buzz and speculation about the ability to secure funds. Missing from this discussion is any concern for whether more people would actually transfer at Secaucus than do today. The instinct is to say that this provides a better connection to most of Midtown, but the transfer penalty literature suggests otherwise.
One important thing to note, writes Reinhard Clever, is that for commuter rail, downtown-side transfers are much more inconvenient than suburb-side transfers. Suburban commuters will drive to a park-and-ride, but balk at a transfer at the city end. Clever’s example is Toronto, where commuter rail riders tend not to transfer to the subway at Union Station but only take transit to jobs that can be reached from the station by walking. This problem is what doomed the Austin Red Line. For all its flaws, ARC offered a one-seat ride from the Erie lines to Penn Station.
Another thing to note is that suburban commuters routinely change trains at Jamaica today, but not at Secaucus. I’m not aware of a study on the transfer experience, but I am fairly certain that the difference is that at Jamaica the transfers are timed and cross-platform whereas at Secaucus they are not. Transferring at Secaucus today involves going up steps, passing through faregates, and going down steps, with no guarantee of a connecting train. The literature is unanimous that passengers will spend more than one minute of in-vehicle time to avoid a minute of transfer or waiting time: the MTA uses a factor of 1.75, the MBTA 2.25, Houston METRO 3.5-4 (last two from pp. 31-2 of Clever’s thesis). None of this is going to change if people are instead made to transfer from a commuter train to the subway, except perhaps that the subway train is going to be less crowded because it won’t be carrying commuters from the Northeast Corridor and Morris and Essex Lines.
Both issues boil down to the same fundamental: not all transfers are created equal. Within urban rail, people transfer all the time. Perhaps the disutility of getting up while changing trains is not an issue when passengers do not expect to find a seat in the first place. Regional rail riders transfer as well, when the transfers are easy and there’s no additional waiting time – in fact, setting up a timed transfer on a highly branched regional line increases the frequency on each branch, so any disutility from transferring is swamped by the more convenient schedule. What people don’t normally do is ride a regional line that gets them almost to their job, and then take urban transit for the last mile.
Commuters on the Erie lines can already make an uncoordinated transfer involving passing through faregates at two locations: Secaucus, and Hoboken. Some, but not many, already take advantage of this to get to jobs near Penn Station or in Lower Manhattan. The contribution of the 7 to Secaucus would then be to create a third opportunity for a transfer to 42nd Street. While 42nd is closer to most Midtown jobs than Penn Station, the heart of Midtown is in the 50s. At Queensboro Plaza more inbound riders transfer from the 7 to the N/Q than the reverse, emptying the 7 by the time it gets to Manhattan: the MTA’s crowding estimate as reported by the Straphangers Campaign, has the taken at the entrance to the Manhattan core, ranks the 7 the least crowded subway line at rush hour. Thus, although the 7 to Secaucus would add to the number of jobs served by a two-seat ride, many Midtown jobs would require a three-seat ride, no different from transferring to the E at Penn Station.
Therefore, good transit activists should reject the 7 to Secaucus as they did ARC, and I’m dismayed to see NJ-ARP‘s Douglas John Bowen throw in his support behind it as an ARC alternative. Before anything else is done, the Secaucus faregates should be removed, and the platforms should be remodeled to let passengers go directly from the Erie platforms to the NEC platforms. Here are better candidate projects for adding a pair of tracks under the Hudson:
1. ARC Alt G. Despite the ARC cancellation, it remains the best option.
2. Hoboken-Lower Manhattan. This doesn’t give Erie commuters a one-seat ride to Penn Station, but compensates with a one-seat ride to Lower Manhattan, and a two-seat ride from the Morris and Essex Lines to Lower Manhattan. The Manhattan terminal should not be more than a two-track stub-end with short tail tracks and the potential for a connection to the LIRR Atlantic Division. With about 50 meters of tail tracks and a platform with many escalators, the Chuo Line turns nearly 30 tph on two tracks at Tokyo Station. It’s an outlier, but given the extreme cost of building larger stations in Manhattan, the response should not be “They’re different, our special circumstances won’t let this happen,” but “how can we have what they have?”. Modern signaling and punctuality are critical, but, as the Germans say, organization before electronics before concrete.
2b. Jersey City-Lower Manhattan. The same as option 2, but with somewhat less tunneling in Manhattan and a lot more tunneling in Jersey. The main advantage is that new underground stations at Journal Square and Exchange Place would serve more jobs and residents than a station in Hoboken. It may be cheaper due to reduced Manhattan tunneling, or more expensive due to less maneuvering room coming into Lower Manhattan. It also forces the Manhattan platform to be east-west rather than north-south for a far-future cross-platform transfer with Grand Central and Staten Island.
3. The L to Secaucus, or to Hoboken. This has all the problems of the 7 to Secaucus plus more – 14th Street is at best a secondary CBD – but it conveniently replaces the L’s current low-throughput terminal with another. Ideally the L should only be extended a few hundred meters west, to the Meatpacking District, but if such an extension has large fixed costs, the incremental cost of extending the L all the way could be low enough to be justified by the benefits of a Secaucus extension, which are low but nonzero.
Electrification and Carbon Emissions
Railvolution reports FTA numbers that say the average CO2 emissions of the New York City Subway are 0.17 pounds per passenger-mile (48 grams per passenger-km). That’s the equivalent of 114.6 passenger-mpg of gas, if you prefer to think in those terms. The presentation gives average seat occupancies, which we can also confirm with the NTD; it works out to about 4 car-mpg of gas. Other agencies can have somewhat different numbers, based on train efficiency and especially the local sources of power generation, e.g. BART has very low emissions coming entirely from the fact that the Bay Area has ample hydro power resources.
New York’s emission number, 4 mpg, may be familiar to you as roughly the emission-efficiency of regional diesel trains. Per ton of car mass the regional diesel trains do slightly better, since the regional train in question weighs 40 tons vs. 33-39 for New York’s subway cars, but this comes from making fewer stops. At agencies with very dirty power generation, such as the Chicago L, and even ones without very dirty power, such as the energy-hungry Washington Metro, the numbers are even lower, even though they’re electric and the regional diesel trains are not.
What we see is then that railroad electrification does not add too much to fuel economy. The question is then why the situation for cars is so different. The Nissan Leaf’s EPA-rated fuel economy equivalent rating is 99 mpg – almost as good as the New York City Subway, better than nearly all subway systems in the US. But if we try to break it down based on energy consumption, we get other numbers; the EPA just massaged the numbers to make plug-in hybrids look good.
The Leaf’s energy efficiency is 0.34 kWh per vehicle-mile, pardon the mixed units; the FTA’s numbers for major US subways range from 0.186 kWh per passenger-mile in high-seat-occupancy New York to 0.388 in low-seat-occupancy Chicago. This is not 99 mpg, unless one uses a fairly clean mixture of fuels; with the New York mixture, it’s 63 vehicle-mpg. So right off the bat, the official numbers underestimate the Leaf’s CO2 emissions by 36%, and overestimate its CO2 efficiency by 57%.
But even that doesn’t take care of inefficiencies in generation. Well-to-wheels, plug-in electric cars have about the same emissions as regular hybrids. This confirms the rough numbers we’ve seen from trains. The Tesla Roadster, a very fuel-efficient car, gets even better energy-efficiency even wells-to-wheels, but it also has much lower electricity consumption, and to get the right numbers it assumes electricity is generated from natural gas rather than coal.
Bear in mind, all of this assumes certain things about the grid mix. At the current US grid mix, on average electrification does not impact carbon emissions. Of course, since people need electricity for reasons other than transportation, any regime in which carbon emissions fall is one in which electricity becomes lower-carbon, and this would tilt the field in favor of all-electric vehicles, both cars and trains.
So, why electrify, if there’s no carbon emission benefit, why electrify? Two answers: air pollution, and, for trains, performance. Electric trains outperform diesel ones, and also cost less to operate in terms of both energy and maintenance. But electrification should be sold only on grounds that are in fact correct.
Pedestrian Observations 
