Macrodestinations and Microdestinations

In her book Dark Age Ahead, Jane Jacobs complains that freeways as built are good at getting people to macrodestinations (downtown) but not microdestinations (particular addresses within city center). In her example from Toronto, this is correct, but in general, each mode of transportation will be good at serving microdestinations in an urban form that’s suited for it. Cars are not good at serving an intact city center; but equally, transit is not good at serving suburban sprawl, and regional rail that’s not integrated with urban transit is not good at serving urban destinations away from immediate train stations.

The idealized job center in an auto-oriented city is the edgeless city. Even the edge city, as explained in Lang and LeFurgy’s now-paywalled article Edgeless Cities, is too dense, and becomes congested too quickly; indeed, Tysons Corner is infamous for its lunchtime rush hour conditions. Ideally, cars drive from low-density residences to low-density office parks, primarily on freeways but with fast arterial connections at both ends; the freeway network in the auto-oriented city serves an everywhere-to-everywhere set of origins and destinations.

In such an environment, transit can’t do well. The distance between suburban attractors is too great for an easy walk, and the roads are too wide and fast for a pleasant walk. Buses and trains can serve a general macrodestination (“Warwick Mall/CCRI”), but not individual microdestinations, not without splitting and cutting frequency to each destination or detouring and raising travel time. The buses serving Warwick Mall and CCRI have hourly frequency, and are a long, uncomfortable walk from the hotel in Warwick I needed to go to. Judging by the frequency, I’m not the only person who chose not to use them, and take a taxi instead; everyone who has a car or who isn’t extremely price-sensitive does. The only way transit can serve such a destination is by concentrating development near the station – in other words, making a mini-transit city in the sea of sprawl, which generally conflicts with the goal of easy station parking.

In a city, the opposite situation exists. It’s easy to just pronounce transit more suited to dense city centers than driving, but the situation is more complicated. Transit, too, thrives on good connections to microdestinations. It can’t serve employment that’s dense but evenly dispersed in a large area – people would need too many transfers, and the result would be service that’s on paper rapid and in reality too slow. Instead, it works best when all destinations are clustered together, in an area not many subway stations in radius.

In this view, one failure of urban renewal is its failure to recognize that most people who visit city centers are going to do a lot of walking, and amenities should make it easier rather than harder. Traditional urban renewal would build cultural centers and other projects at the fringe of the CBD, to help its growth: Lincoln Center just north of Midtown, Civic Center just southwest of the San Francisco CBD, Providence Place and Providence Station just north of Downcity. In New York and San Francisco, there’s at least rapid transit serving those destinations, mitigating the effects. In Providence, no such thing exists. It’s an inconvenient walk from Kennedy Plaza to the mall and the train station – it’s not too long, but it crosses Memorial Boulevard right when it turns into a freeway on-ramp. Walking to the Westin, immediately adjacent to the mall, is practically impossible without rushing across roads without crosswalks. Even the walk between the station and the mall, which were built together and are close to each other, is much worse on the street than on a map, again involving crossing auto-centric roads.

Organic city amenities do not look like this. If they cluster at the same location (for example, 125th Street in New York, or Thayer Street in Providence), they tend to be along roads that facilitate rather than hindering pedestrian movement. And if they don’t, they are all located along a rapid transit network in its shared service area, where it is still a tight mesh rather than a network of radial lines.

In view of the recent emphasis on parking policy, due to Donald Shoup but now mirrored by other urban planning and transportation experts, the observation is that in any city center, on-site parking is difficult to find. Even in cities that make downtown parking relatively easy to get to, people can’t hope to park at every single microdestination, so instead they trip-chain, driving into the city and parking but going to multiple points within the city, all within a short and easy walking distance from one another. This is roughly the urban geography of the French Riviera, which combines easy parking with a dense, lively center in Nice and a fair amount of urbanity on some streets even in auto-oriented secondary cities such as Monaco and Menton.

The connection to regional rail is that, historically, it descends from intercity trains, and therefore the conception of connecting the suburbs to the city is very macrodestination-driven. To name two egregious American examples, the Boston’s north side lines and Caltrain both connect many suburbs to the city while also connecting people to the suburban tech job corridor, but in reality miss the biggest job centers at both ends. North Station is two subway stations north of the CBD, and as a result ridership underperforms the south side lines; 4th and King is far enough outside the Market Street CBD that it’s not close to the CBD jobs – the proposed Transbay Center site, which is, is located near more jobs than all existing Caltrain stations combined. And if microdestination-level service to an already transit-oriented CBD is bad, then service to other urban destinations is worse: urban station spacing is wide, there’s no attempt to develop near stations, and the poor integration with local urban transit ensures that even people who could be willing to make the last-mile transfer don’t.

Trip Chaining

Gendered Innovations’ charts of trip chaining and gender breakdown of public transit riders got me thinking about how different systems of transportation handle a mixture of short and long trips. Eric Jaffe at The Atlantic Cities reports this and suggests that transit agencies orient physical features such as accessibility to the needs of women who trip-chain care and work trips.

But to me, the first observation is that although women trip-chain more, it doesn’t seem to be true that women are more likely to ride transit in the US than men just because of trip-chaining features. Instead, women traditionally have been less likely to have jobs requiring commuting, and the commute gap has been shrinking more slowly than the gap in employment.

This comes from the fact that trip chaining on transit is cumbersome in most cases. Both cars and transit have to deal with the time it takes to stop for an errand, but transit tends to handle this worse, unless it’s very frequent and has practically zero access and egress times. Transit cities instead get people to take their short errand trips on foot – since their neighborhoods are denser and have more mixtures of uses, they make retail and care trips attractive on foot. In light of the fact that walking is not useful for long commute trips and transit is not useful for short errands, we can construct the following typology of cities:

Long \ Short mode Foot, bicycle Car
Transit Transit-oriented Traditional suburban
Car New urbanist, small-town, auto-oriented dense Auto-oriented

Auto-oriented cities are the easiest: in those places, people drive for all purposes. Trip chaining can be done on a commercial arterial road, dropping off laundry or kids or buying something on the way to work, and because of ample parking availability, the time each additional link in the chain consumes is very small, since the longest access and egress time comes from navigating from the residential cul-de-sac to the arterial and from the arterial to the office park.

Traditional suburbs, common around New York and Chicago and sometimes in other old North American cities, are similar for trip-chaining purposes. In those areas, the urban form is suburban and auto-oriented, but work trips to the city are done by commuter rail or occasionally commuter bus, since the city is not as auto-friendly as the suburbs.

Transit cities too have their long-range commuter rail, but it is built as an extension of walking rather than of driving. Neighborhoods tend to have mixed uses, and there’s a concentration of retail development near the outlying stations, sometimes forming large secondary clusters but sometimes just acting as neighborhood centers. It could take considerable time to add more trips to one chain, especially if not everything is located at the train station. But conversely, the amount of time a single short trip takes is small, unlike the case for auto-oriented cities – the supermarket is right around the corner, and within five minutes’ walk are plenty of stores. When people walk, the concept of a single trip begins to lose meaning then. Potentially, every single purchase can be considered a separate trip, in which case the chaining becomes quite long.

In many places the transit is absent and people drive outside the neighborhood, while still doing errand trips on foot. This is the typology that characterizes different environments including new urbanism, traditional cities like Providence and Tel Aviv that have been made car-oriented, and auto-oriented modernist projects such as Co-op City. Those environments all differ in how trip chaining is done. In principle, it can be done on foot, but usually people who can drive do.

If my own experience is any indication, one feature of cities in this typology is that children and teenagers walk more. In Tel Aviv, my father drove me to elementary school on the way to work while (in later grades) I walked back, and I took the bus to and from middle school. Most trips my parents did in a car, but there was a reasonable number that were short enough to walk. I’d walk to farther destinations such as the cinema and the urban mall. The view of the North Tel Aviv middle and upper-middle class of the 1990s as I remember it is that the bus is fine for trips to school, but adults drive. I doubt I’d have had the same view if I’d grown up in New York, or for that matter in the Houston suburbs, where everyone drives or is driven.

Although most of the discussion about transit cities contrasts them with car-oriented cities, the other two typologies need to be examined, too. When adults and children trip-chain differently, children can get a distorted view of who transit is for (poor people, people who can’t drive yet), and the next generation will make the city auto-oriented; this is indeed what is happening in Tel Aviv, which despite population growth in the core is adding cars and spawning low-density suburbanization well outside the built-up urban areas.

Likewise, Cap’n Transit’s attacks on park-and-rides don’t quite capture what is wrong with the car/transit typology. A transit agency that wants to make it easier to trip-chain will want to concentrate development near the train stations, because that’s where it’s easiest to add minor trips without having to walk ten minutes out of one’s way. Of course in the middle of the dense city there’s development everywhere, which may well be orthogonal to where the subway is, but then trip-chaining becomes easier because each foot trip is so short.

The principle is that cars are a big one-time purchase but have a much lower marginal cost of usage. If one major class of trips can’t be done on transit – and chained trips generally can’t when they require the rider to wait for the next bus and the next bus will come in 15 minutes – then people will buy a car and then drive it even for trips they’d happily take transit to if they didn’t already own a car. The class of trips that can only be done conveniently by car needs to be kept small enough that people will use car share, take a taxi, or beg a friend who does own a car.

Thus what transit agencies and pro-transit politicians should devote more time to is appropriate development more than physical features of the transit system. Accessibility is important for so many reasons other than strollers. In contrast, the primary importance of using transit to extend the range of the pedestrian rather than provide a capacity boost for the car is precisely that transit needs minor trips to be doable on foot. A transit system that one needs to take to the supermarket may be technically successful, but it’s in a failed urban area.

More on Cost Comparisons

Some of my past posts on cost comparisons are getting play on mainstream publications including Slate, Salon, The Economist, and The Atlantic Cities, and one of the consistent points I see is that the difference between the US and most of the rest of the first world is so glaring that projects that are locally considered boondoggles suddenly look good.

A list containing multiple projects at over a billion dollars per kilometer can legitimize anything below it. Thus projects approaching half a billion per kilometer look downright reasonable. In reality, Tokyo Metro said that there will not be further subway construction, and I have read elsewhere that it repeated this promise in advance of its impending IPO. And in Amsterdam, an inquiry into the North-South Line’s factor-of-2 cost overrun concluded the project should have never been built.

It seems that there’s an Overton window analog, in which higher costs legitimize the previous decade’s work, making it look good when at the time it was criticized for poor cost control. In fact, this could explain the decades-long trend toward increasing real costs – an explanation that is usually given in terms of rising wages and worker safety rules, but in reality poor countries build subways for not much less money than non-Anglophone rich countries.

I contend that the best practice should still be to compare with the average, rather than with either the worst (London Crossrail, Amsterdam North-South Line, Munich Stammstrecke 2) or the best (most projects in Spain). Being more expensive than one city could be a fluke. Being five or more times more expensive than upward of 90% of subway projects is less excusable.

Most interesting to me in this discussion is the explanations for US/Europe cost differences. Although most people regrettably keep comparing the US to China, never mind that European and Chinese costs are similar, some stay on target and avoid explanations that assume the entire first world is like the US. One comment on The Economist follows:

Observations on the public construction process, having seen it in action relatively up close:

1. Failure to embrace technology except in the most expensive cases. We are behind in construction techniques overall. We will bring in European methods when the case is made they are necessary. These methods therefore tend to be used when the expense is higher. This means we don’t upgrade technology overall, just at the costly fringes. Examples come from the methods used to construct the new tunnels in Boston; one used a method developed mostly by the Dutch because our domestic methods weren’t up to it.

2. Our project management is not equivalent. European large scale construction projects run more just-in-time. Even really big ones require very large things to be built and then to arrive on a schedule. Our system can’t handle that so we build in lots of slack expecting stuff will come late and will need to be adjusted – sometimes substantially – to fit the need. That is very costly.

3. Our system is very bad at prioritizing. My experience with this is mostly at the state and local level. I have seen very competent people working at both levels. They exist in a morass of work that needs to be done. They don’t have the resources to do things properly. They have to put repair, snow, etc. way, way, way ahead of planning.

4. My overall comment is this: Europeans understand they exist in a high cost environment so they squeeze out the inefficiency to be competitive. They focus on value-added design and on efficiency in planning and scheduling. We don’t.

Bad Defunding

The furor in the transit blogosphere about the House Republicans’ transportation bill proposal, defunding the Mass Transit Account and diverting the money to roads in order to shore up the Highway Trust Fund, deserves more scrutiny from the point of view of government effectiveness. Although the proposed defunding is clearly political and cultural (to many Tea Party Republicans, trains and buses are for hippies), the way in which it is done is a good reminder about what’s going on in US politics. The principle is that when government does not work, the people in government who propose to get rid of it are part of the same ineffective governance structure.

First, consider some recent projects or proposals for projects to expand transit. In Houston, as noted by rail critic Tory Grattis, of the four proposed light rail lines, the first two to be built are the less cost-effective two, while the more compelling Universities Line is saved for later. In Los Angeles, the Foothills Extension is being built before the Westside Subway. And the first California HSR contract to be tendered is for the northernmost initial construction segment, the segment that should be first on the chopping block if necessary to divert money to the more important Los Angeles-Bakersfield mountain crossing. In order to prevent smart scope changes from leaving the cost-ineffective parts out, the planners take the cost-effective lines hostage in order to make sure that they are built.

The same is true in the opposite direction. It was not so clear up until now because the big-ticket rail cancellations all involved just one major project per governor, but now that the Republicans are bundling all transit together, the pattern looks clearer. There is no accounting for good and bad projects here. Even cost-effective projects such as Second Avenue Subway would lose funds they need for completion. The goal is not to cut government waste; it’s to cut spending on people who the people who proposed the bill find distasteful, and the effect of quality of government services is about what you’d expect of any politicized government program.

It’s for the same reason that I think very little of Chris Christie’s ideas about transportation management, despite my criticism of ARC. Although some of the rumors floated suggest that the depth of the cavern was one of the things that made Christie think the project was ridiculous, he made no effort to try fixing it. Instead, he canceled the project, trumpeted it as a cost saving measure, and proceeded to spend more money on freeways. Aaron Renn, hardly an orthodox leftist (he is a fan of Mitch Daniels), compared him to Chainsaw Al and called his style of governance kindergarten-level.

In analogy with technical and political transit supporters, there are technical and political road supporters. The technicals exist, in various driver magazines that support spending more money on maintenance and less on expansion, and do not mind raising tolls or gas taxes to pay for infrastructure. But the politicians do not care about cost-effectiveness, and have no problems supporting Big Dig-style projects. At the risk of overinterpreting blog comments, let me say that every road supporter I have seen express an opinion on the Big Dig thinks that it was a necessary project and should have been built regardless of the cost (for the record, $15 billion for what to the best of my understanding is about 200,000 cars per day). The thinktanks that support them care more about finding ways to convince people to want to pay more money for expensive freeways rather than about cutting the cost of construction or reducing environmental impacts.

Thus the House transportation bill is bad not only because it’s bad for transit, but also because it’s bad government. It’s not even selective worrying about cost-effectiveness, a charge often thrown by political transit supporters. It makes no attempt to decouple any funding from gas taxes, a decoupling that it necessary for the purpose of making it possible to tax pollution without demands from both APTA and the AASHTO that the revenues raised be plugged back into transportation. It makes no attempt to let go of projects that cost too much while maintaining those whose cost is adequate. It’s purely an exercise in muscle-flexing, a continuation of the US practice of not having a transportation policy that’s separate from the usual political and lobby bickering.

Why Long Island Should Get An HSR Spur

Having looked into why high-speed rail from New York to Boston should go through Providence, I want to explain why it should go through New Haven, rather than through any of the fanciful Long Island routings proposed most prominently by the Penn design group. Like Hartford, Long Island should have high-speed trains use the LIRR Main Line, but at medium speed rather than high speed, and with careful consideration to the much more important needs of commuter rail.

Although the LIRR Main Line shares one characteristic with the New Haven-Springfield line, namely that it is very good for 160-200 km/h but bad for 300, the reasons are subtler and less geometric. The most visible is NIMBYism. Even increasing the traffic of existing LIRR trains raised the ire of some suburbs along the Main Line, which opposed the three-tracking project (since canceled due to budget shortfall) on the grounds that extra train traffic would reduce quality of life and that eminent domain would be required. This is not Caltrain, whose local residents do not know what electric trains sound like; this is Long Island, which has lived with these trains for generations. Introducing HSR is asking for trouble.

Of course, the same could be said about any suburb that HSR needs to pass through. Connecticut is full of NIMBYs, just like Long Island. The reasons usually given for avoiding the existing Shore Line are that it’s too developed and has too much local opposition. But those are present on Long Island, and are worse because of the higher population density. For examples, compare Westport and Cos Cob with Brentwood and Farmingdale. The LIRR offers multiple straight rights-of-way, but all are going to have the same speed limits as heavily upgraded and modified tracks on the Shore Line – 250 km/h in the better parts, and 200 in the worse parts.

The Penn design proposal is not even the best Long Island proposal, for three reasons:

1. It insists on proceeding from Penn Station to Jamaica on the Lower Montauk Line. If a connection from the line to Penn Station opens, it’ll be far more useful for local rail, while intercity rail can use the Main Line. The difference between appropriating a Manhattan-accessible Lower Montauk Line for HSR and replacing the Lexington Avenue Line with a truck tunnel is one of degree, not kind; in both cases, local passenger rail is the most valuable use of the infrastructure.

2. It departs from the Main Line to use the Hempstead Branch (necessarily eviscerating commuter service) as well as abandoned tracks through endless residential suburbs, full of urban grade crossings. The Main Line has grade crossings and would need to be four-tracked, but the local NIMBYs actually supported grade separation, and multi-tracking at least could be sold as the local transit improvement project that it is.

3. Last and worst, it sharply veers north after stopping at Ronkonkoma, along a curve whose radius judging by the alignment map is around 900 meters (=150 km/h if superelevation and cant deficiency are set at normal HSR levels, or 170 km/h at cutting-edge levels). Then it crosses the Long Island Sound at its widest, so that it adds more than 20 kilometers to the New York-New Haven route length over the Shore Line, all at medium speed.

A route similar to the Penn design route but using the more feasible Main Line alignment would be 9 minutes slower than the optimal Shore Line route – 41 versus 32 minutes – with stops at Jamaica and Hicksville, enforced by unfixable track curvature near the stations. But in addition to the extra travel time, fixing the alignment through New Rochelle, Darien, and Bridgeport is far cheaper than a long undersea tunnel. A better Long Island route would follow the Main Line to the end and tunnel near Greenport, trading deeper waters for shorter tunneling and a route length comparable to that of the optimal Shore/I-95 alignment, so it could achieve a comparable trip time. But even that’s unneeded: it’s 15 km of deep tunneling, whereas if one is willing to slightly compromise on trip times, the only Connecticut tunneling required for a Shore Line fix is 3 km in Bridgeport.

The other problem is what to do about commuter service. The Providence Line’s traffic level is low enough and its average interstation is long, allowing a blended plan. Shared tracks between New Rochelle and Penn Station would see more commuter traffic, but intercity trains would go slower anyway, and there is more room for four-tracking. The Ronkonkoma Branch’s 10-minute peak service requires at least one overtake between Hicksville and Ronkonkoma and probably two, in addition to four-tracking the Main Line; this is feasible, but less than optimal, and the overtakes would have to be constructed in more constrained locations than those available on the Providence Line. East of Ronkonkoma commuter service may need to be cut, but this is less of a problem on account of its low traffic. On the other hand, the Main Line west of Hicksville is not a problem with four tracks, and neither is the New Haven Line – express commuter trains could weave in and out.

On the benefits side, offering Long Island service to Boston that doesn’t go through New York is better than not doing so. However, the difference in benefits with New Haven, while positive, is smaller than it seems. The New Haven Line has almost as much ridership as the LIRR Main Line, and Stamford is a bigger edge city than Mineola and Garden City. On top of that, since the optimal LIRR option connects to the Shore Line in the far east of Connecticut, there is no hope for service to Hartford except on legacy track. On balance, the advantage of the LIRR option is just service to Jamaica, a larger draw than those smaller cities and suburbs, but there the time saving is the smallest.

On top of that, does such a small benefit really justify the cost? Having some high-speed trains run through to Jamaica, Mineola, Hicksville, and Ronkonkoma at lower speed requires re-electrifying the LIRR with catenary, which is a fraction of the cost of all those urban grade separations and 1-2 order of magnitude cheaper than an undersea tunnel and land connections. On a similar note, since half an undersea tunnel is of no use, it’s harder to break construction into small chunks if it is necessary, putting it at a disadvantage against a route consisting of cutoffs and modifications of the existing line. The route of 1834 may work now that we can build tunnels, but the cost structure favors that of 1846 and 1852.

Formal Announcement

Those of you following my Twitter feed already know this: I’m moving to Vancouver sometime in this summer for a two-year position at UBC. Expect a dramatic reduction in the number of posts expressing exasperation with local transit planning beginning sometime in July or so. I will try to keep writing about the Northeast and not just about Vancouver.

High-Speed Rail Should Serve Providence

The most straightforward part of constructing greenfield tracks for high-speed rail on the Northeast Corridor is east of New Haven. There are good legacy lines to hook into, and good Interstate corridors to follow when the legacy lines are too curvy. It’s also the segment with the biggest variation in alignment options, which boil down to going through Hartford and going through Providence. Both the Penn design proposal and the Amtrak proposal go through Hartford and avoid Providence, and this is a bad idea, for both costs and benefits reasons.

See here for a very early and rough draft of my HSR map, which goes through Providence; there are significant issues with this map west of New Haven, but it’s fairly accurate east of Haven. It uses I-95 between New Haven and the state line, and transitions to the legacy line around Kingston; Hartford would be served on the legacy line, which would be electrified. I have not seen detailed drawings of Amtrak’s proposal, but here is the detailed Penn design map, going through Hartford: the idea is to use a combination of I-91 and a heavily upgraded legacy line, and then transition to I-84 in Hartford and then I-90, while retaining the Shore Line for slower service to Providence. The latter option turns out to be inferior, essentially because full HSR is easier to build through Providence whereas a medium-speed branch is easier to build to Hartford.

First, the cost side. Because the portions of the Shore Line used by the Providence option are straight and already built to high standards, minimal upgrade work is required there. The bulk of the cost would be constructing high-speed track along a mostly flat, not very developed right-of-way, with two and a half painful segments (New London, the cutoff east of New Haven, and the Connecticut River crossing as the half). East of New London the median is available, cutting costs further. All in all, this is 125 km of largely at-grade track, and about 60 km of cheap electrification to Hartford.

Going through Hartford is about equally hard. The New Haven-Springfield line is built to low-speed standards, with grade crossings and curves that are good for 200 km/h rather than 300. It avoids the river crossings of I-95, but I-84 and I-90 are a bit curvier and follow more rugged and urbanized terrain, and the urban segment through Hartford looks harder than that through and immediately east of New Haven. Per kilometer it could cost about the same, but 200 km of new track are required.

The costs by themselves are not a huge deal. The New York-New Haven segment requires new grade-separated junctions, multiple bypasses, and some urban tunneling. In contrast, mostly at-grade track costs $20 million per kilometer or not much more, so despite the large difference in length, the difference in cost is about $2.5 billion vs. $4 billion.

However, there’s also a constructability argument for I-95, which is that it can be done in segments more easily, using portions of the Shore Line before the full line opens. This could be useful if money were made available in very small chunks. The Hartford route could be done partly on an electrified Springfield line, but Hartford-Boston has to be done in one go.

But a bigger issue is that going through Providence has two advantages over going through Hartford without regards to costs. First, Providence is a larger city than Hartford: its metro area is about 20% larger than Hartford’s, and the central city is 40% larger and denser. Although the Hartford option passes near Worcester, there is no way to bring a station into Worcester itself without excessive tunneling; the Penn design plan puts the station at the edge of the built-up area, 7 kilometers from downtown Worcester. The Providence option passes through much smaller New London, but it can at least be served by a station that’s within the city, one km from the present station.

The other advantage is how to serve the city that does not get to be on the HSR mainline. The Springfield line is easy to upgrade, since it is straight enough for medium speed, and grade crossing protection good for about 180 km/h is relatively cheap. This would give Hartford very good service to New York – about half an hour to New Haven, and a little more than another half an hour to New York. The Shore Line in contrast is curvy and slow and already has a fair amount of superelevation and cant deficiency, making future upgrades much harder. Providence would still get better trip times than today coming from better rolling stock and higher speeds west of New Haven, but better trip times than about 1:45 to New York are only possible with trains with high degree of tilt, which tend to be a maintenance nightmare.

For the record, my original proposal above is from 2009, and I only accepted my current job at Brown in 2011. However, in the interest of full disclosure, by 2009 I already knew that Brown had one of the best departments in my field, whereas Hartford doesn’t have a research university of comparable quality. I don’t think it biased my choice – the idea of following the present alignments and serving present lines as much as possible appears elsewhere in the plan as well as in my regional rail proposals for New York and Boston – but then again nobody thinks their own choices are biased.

MBTA Mode Shares

As a followup to my claim in my first post about improving the MBTA about the low mode share of commuter rail for trips into Boston, here are some figures about commuter rail use, by sector. All numbers exclude commuters from inner suburbs and from Boston itself, since those would use the subway. Only Boston-bound commuters are included. I’m providing wider and narrower numbers, wider numbers corresponding to the entire sector defined by a commuter line and narrower numbers including only towns within reasonable range of a commuter station.

All commuter rail numbers come from the Bluebook and are averages as of February 2009, from page 74; be careful not to use numbers from the map on page 70, as they inflate the ridership on the Providence Line. All commute market numbers come from the 2000 census; I do not believe commuting patterns have changed so radically as to significantly alter the picture.

Update: we obtain the following table, explained below (see also computation error fix for Haverhill):

Line Wide market Narrow market Riders Share of wide Share of narrow
Old Colony 43,587 34,934 20,907 48% 60%
Providence, Stoughton 23,297 17,490 11,719 50% 67%
Franklin 14,899 12,747 7,043 47% 55%
Worcester 19,997 15,581 7,479 37% 48%
Fitchburg 16,544 13,358 5,883 38% 44%
Lowell 15,551 11,912 5,586 36% 47%
Haverhill 19,196 16,902 8,922 46% 53%
Newburyport, Rockport 26,926 25,534 13,230 49% 52%

Old Colony Lines (including Greenbush)

Commute market (wider): all of Plymouth County; Cohasset, Weymouth, Randolph, Holbrook, and Avon towns in Norfolk County

Commute market (narrower): including only the above Norfolk County towns and Plymouth County’s towns of Abington, Bridgewater (including East and West), Brockton, Hanson, Hingham, Hull, Kingston, Lakeville, Middleborough, Plymouth, Rockland, Scituate, and Whitman

Commuter volume (wider): 43,587

Commuter volume (narrower): 34,934

Inbound commuter rail ridership: 12,065 (excluding JFK-UMass, Quincy, and Braintree)

Extra transit use: 7,244 subway and commuter rail boardings in Quincy and Braintree beyond those accounted for by those two towns’ commuter market; 1,598 commuter ferry riders, mostly from Hingham

Mode share: 60% of the narrow market, 48% of the wide market

Providence and Stoughton Lines

Commute market (wider): all of Rhode Island, all of Massachusetts’ Bristol County, and the towns of Sharon, Canton, Stoughton, and Plainville in Norfolk County

Commuter market (narrower): the three Norfolk County towns omitting Plainville, all of Rhode Island’s Providence and Kent Counties, and Massachusetts’ Bristol County’s towns of Attleboro (including North), Mansfield, Easton, Norton, and Seekonk

Commuter volume (wider): 23,297

Commuter volume (narrower): 17,490

Inbound commuter rail ridership: 11,719

Extra transit use: none

Mode share: 67% of the narrow market, 50% of the wide market

Franklin Line

Commute market (narrower): Norfolk County’s towns of Dedham, Westwood, Norwood, Walpole, Norfolk, and Franklin

Commute market (wider): the above plus the towns of Medfield, Medway, and Wrentham

Commuter volume (wider): 14,899

Commuter volume (narrower): 12,747

Inbound commuter rail ridership: 7,043

Extra transit use: none

Mode share: 55% of the narrow market, 47% of the wide market

Worcester Line

Commute market (wider): all of Worcester County except Fitchburg, Harvard, Westminster, Gardner, and Leominster; Wellesley; and Middlesex County’s towns of Natick, Ashland, Framingham, Marlborough, Hudson, Hopkinton, Holliston, and Sherborn

Commute market (narrower): Wellesley; Middlesex’s above counties omitting Hudson, Holliston, and Marlborough towns; and including only Worcester County’s towns of Southborough, Westborough, Northborough, Shrewsbury, Grafton, Worcester, Auburn, and Millbury

Commuter volume (wider): 19,997

Commuter volume (narrower): 15,581

Inbound commuter rail ridership: 7,479 (west of Newton only)

Extra transit use: none, as all Green Line usage is accounted for by Newton commuters

Mode share: 48% of the narrow market, 37% of the wide market

Fitchburg Line

Commute market (wider): Worcester County’s Fitchburg, Harvard, Westminster, Gardner, and Leominster towns; Middlesex County’s Belmont, Waltham, Wayland, Weston, Concord, Sudbury, Acton, Maynard, Stow, Lincoln, Littleton, Boxborough, Ayer, and Townsend towns

Commute market (narrower): Worcester County’s Fitchburg and Leominster only; Middlesex County’s above towns, omitting Stow, Townsend, Wayland, and Sudbury

Commuter volume (wider): 16,544

Commuter volume (narrower): 13,358

Inbound commuter rail ridership: 5,883 excluding Porter

Extra transit use: two local bus lines (70, 70A) to Waltham with 4,343 trips in each direction and two more express lines (553-4) with a combined 681 trips (none serving just Waltham, but also Newton or Cambridge), but conversely much of the ridership Waltham generates is non-commuter student traffic

Mode share (assuming neutral Waltham effect): 44% of the narrow market, 36% of the wide market

Lowell Line

Commute market (narrower): Middlesex County only, towns of Winchester, Wilmington (half, shared with Haverhill Line), Woburn, Billerica, Lowell, Chelmsford, Tewksbury, and Dracut

Commute market (wider): the above, plus the Middlesex County towns of Dunstable, Westford, and Tyngsboro, and all of New Hampshire’s Hillsborough County

Commuter volume (wider): 15,551

Commuter volume (narrower): 11,912

Inbound commuter rail ridership: 5,586 excluding West Medford

Extra transit use: none – if anything, this line is missing more of its potential coming from its inability to serve Medford well under current commuter rail paradigms

Mode share: 47% of the narrow market, 36% of the wide market

Haverhill Line

Commute market (narrower): Middlesex County’s towns of Melrose, Stoneham, Wakefield, Reading, North Reading, and Wilmington (half, shared with Lowell Line); and Essex County’s towns of Andover, North Andover, Lawrence, and Haverhill

Commute market (wider): the above, plus Essex County’s towns of Boxford, Middleton, Groveland, and Lynnfield

Commuter volume (wider): 19,196

Commuter volume (narrower): 16,902

Inbound commuter rail ridership: 5,343 excluding Malden

Extra transit ridership: Malden’s two subway stations get 8,375 riders beyond the commute market, but they could be coming from people from Everett and Medford – let’s just add the number of parking spaces, which is 976, plus one half of the remaining ridership at Oak Grove, representing Melrose and Stoneham’s share, which is 2,603 (total bus ridership in Malden and the cities to its north is 3,394 in each direction, and I’m willing to believe 2,603 of this is from north of Malden)

Mode share: 53% of the narrow market, 46% of the wide market (update: a previous version of this post gave slightly lower numbers coming from forgetting to add the 976 subway parking spaces to the imputed ridership)

Newburyport and Rockport Lines

Commute market (wider): all of Essex County except the towns of Andover, North Andover, Lawrence, Haverhill, Boxford, Middleton, Groveland, and Lynnfield

Commute market (narrower): Essex County omitting, in addition to the above, the towns of Amesbury, Georgetown, Essex, West Newbury, Topsfield, and if one wants to be very narrow then also Saugus

Commuter volume (wider): 26,926

Commuter volume (narrower): 25,534 with Saugus, 22,999 without

Inbound commuter rail ridership: 8,821 excluding Chelsea

Extra transit use: no rail, but likely high bus ridership coming out of Lynn – total North Shore ridership is 4,409 in each direction excluding the 430, which is assigned to the Haverhill Line, and some lines that do not serve subway stations (429, 431, 435, 436, 451, 455, 465, 468)

Mode share: counting commuter rail only, 38% of the narrowest market and 33% of the wide market; counting also buses, 52% of the narrow market including Saugus and 49% of the wide market

Conclusion

The best-performing sectors capture about half the ridership of their general area of service and two-thirds of the ridership coming from the towns served by transit. Except for the Providence Line, this requires heavy use of subways and buses; the high contribution of commuter buses north of Boston suggests that better regional rail service, with more useful frequencies and integration between the CharlieCard and Charlie Ticket, really would make a difference, effectively railstituting the trip to Boston and allowing redirecting the buses to feeder service. The worst-performing lines only capture a third of the market, and for those there’s less that can be done; regional rail improvements would help, especially with regards to speed and reliability, but often those areas are too sprawled out.

Another conclusion is that for the purposes of constructing timetables for an electrified, FRA-free MBTA, we should ignore current ridership patterns, and instead look at the volume of commuting. The southwesterly slice serving Providence is not special; it just gets higher mode share on commuter rail since the service levels are higher than elsewhere. A 15/30 timetable on each line or branch (counting Kingston and Plymouth as one, but not any other split) would more or less approximate market demand; it would still underserve the South Shore, but the South Shore has ferry use and subway use, and therefore there’s no lower-level service to replace with good commuter rail.

A third conclusion is that it matters whether commuter rail can serve shorter trips or not, such as trips from Waltham, Medford, Malden, Lynn, and the Fairmount Line area. Those towns and neighborhoods have much larger volumes of commuters heading toward Boston than farther-out towns. This observation favors the regional rather than intercity interpretation of commuter rail, sacrificing speed in order to improve coverage in the innermost suburbs and in outer-urban neighborhoods.

On no line is express service a good proposition except when it’s downright intercity service, such as high-speed rail to New York via Providence, or even intercity trains to Maine or deep into New Hampshire. The problems coming from runtimes that aren’t a short turnaround time less than an even multiple of 15 minutes should not be fixed with express trains, but with closing some stations that aren’t necessary (such as River Works and Mishawum), and building more infill together with the North-South Rail Link, redistributing lines in such a manner as to maximize efficiency. For example, if the branch from Lynn to Marblehead is reactivated, then even with several additional infill stops, trip time from North Station to Marblehead would be about 22 minutes, which together with time gains from the tunnel (travel time through the rail link should be a hair lower than a turnaround time) would allow mixing with the Worcester Line. Currently it’d be difficult to do Worcester-Boston in 55 minutes even under best operating assumptions, and impossible with infill stations, but with the rail link and through-service to Marblehead, the limit would be closer to 1:01, and this allows a few infill stops in Brighton.

What’s driving all of this is the fact that there isn’t all that much demand mismatch. The South Side lines have a larger (wide) market than the North Side lines, but the difference is much smaller than the difference in ridership, and decreases even further if one lets the subway take care of certain parts of the South Shore. This means that, in terms of planning, all lines should be upgraded and should receive ample attention toward service levels, and in terms of operations, through-service should be based on infrastructure capabilities and scheduling constraints rather than on service demand matching.

The Limits of Clockface Scheduling

This is morally the last post in my series on improving the MBTA: see here, here, and here for the three previous posts. However, it’s a more general principle concerning interlined regional rail services.

Good practice for running transit service that isn’t at show-up-and-go frequency – say, anything that comes every 10 minutes or more, certainly anything that comes every 15 minutes or more – is to have regular clockface intervals. This is memorable for passengers, and works as a baseline with which to work on providing extra connections. In addition, if there is interlining, then it makes it easy to schedule trains to come at a uniform frequency on the share segment. If service is uniform throughout the day, then this is very easy. The problems start when it is not.

Normally, if extra peak service is required, then rigid clockface systems, such as those found in the German-speaking world, will usually interpolate in the middle of the period. In other words, if a station gets inbound trains at :00 and :30 every hour, then in the peak it will also get them at :15 and :45. This is what’s done in Stuttgart on two of the S-Bahn lines, interpreting peak very liberally, and less rigidly on the TER in Nice. Many systems instead use similar peak and midday service, dropping service only in the evening, such as the Berlin S-Bahn, and BART.

To see where problems could occur, let us look at Berlin again. There are three services on the Stadtbahn: the S5, the S7, and the S75. At the peak, all three run every ten minutes, with westbound trains departing Ostkreuz at :02, :00, and :05 respectively. Off-peak, the S75 drops to 20-minute frequencies, introducing 8-minute gaps into a schedule whose average headway is 4 minutes.

For a cleaner, contrived example, let’s say we interline two services, each with a 15/30 frequency; a factor-of-2 difference in frequency is more or less the norm on commuter lines in Tokyo and Paris, which do not have rigid clockface schedules – more local lines have a slightly smaller gradient than more long-distance lines. There is an inherent tradeoff between uniform frequency at the peak and uniform frequency off-peak. It’d be much easier to do if both services were bound to have the same frequency but the frequency varied continuously, as it does on most subways; however, what works on a dedicated line when passengers show up and go fails when passengers consult schedules and when timed connections or overtakes are involved.

More concretely, if Line 1 leaves a station at :00 and Line 2 leaves at :08, providing uniform peak frequency of 7-8 minutes, then off-peak we will have a 22-minute gap when we reduce to half-hourly frequency on each line; and if Line 2 instead leaves nearly at :15 to provide uniform off-peak frequency, then there will be a gap of nearly 15 minutes at the peak. The sum of the largest peak and off-peak gaps is necessarily 30 minutes, whereas the ideal would be for the sum to be 22.5 minutes.

Extra constraints can force one choice of gaps. For example, the Providence and Stoughton Lines are (or should be) constrained by the need to fit faster intercity trains on the line, at least in the future; for details of those constraints, see my posts on MBTA-HSR compatibility. In short, if we choose the symmetry axis to be :00, then Providence Line trains are compelled to leave South Station at :02 to meet up with trains to Woonsocket, and high-speed trains leave South Station at :10-11 and begin to overtake Providence trains at Readville at :15. Stoughton trains should then leave immediately after the high-speed trains so that they can leave the line toward Stoughton just before they’d get overtaken (at Sharon, if they continued), which means at :12-13. Thus we obtain about a 10-minute gap at the peak and a 20-minute gap off-peak, which is an acceptable compromise.

In contrast, one thing that clockface scheduling does not limit is short-turns. Indeed the Berlin S-Bahn often short-turns every other train, without trouble. Moreover, it is not difficult to drop to half the peak frequency with short-turns. If a train that leaves at :00 runs all the way to the end and a train that leaves at :08 short-turns (both repeating every 15 minutes), then it is not difficult to change things so that in the off-peak, a train that leaves at :00 or :30 runs to the end and a train that leaves at :15 and :45 short-turns. People beyond the short-turn point would still only need to memorize at what minute between :00 and :29 the trains serve their stations, and it would be regular all day; people before the short-turn point would again only need to memorize one number, from :00 to :14. In the case of the MBTA, this means that the Fairmount Line (which should get a train that turns at Readville for every train that continues toward the Franklin Line) can get a perfectly regular timetable.

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.