Bus vs Rail, an “Oversimplified Comparison”

Planetizen points out a new paper by Jeffrey R. Brown and Gregory R. Thompson of Florida State University, called “Bus vs. Rail: an Oversimplified Comparison.”  From the abstract:

There is debate about the relative merits of investing in rail or
express bus modes to improve regional transit performance. The debate
largely assumes that both modes serve a single function of providing
higher speed service to the central business district (CBD) over
relatively long travel distances. The debate generally overlooks other
functions that might be served by express bus and rail transit modes
and thus ignores that the two modes may perform differently depending
on the service mission they are assigned. Performance of the two modes
is examined in four metropolitan areas with different strategies for
providing high-quality, regional transit service: a CBD-focused
strategy, a hybrid strategy that serves the CBD and a few other
destinations, and a multidestination strategy that serves a widely
dispersed set of destinations. … It was found that the combination of a
rail transit backbone and a multidestination service strategy leads to
better performance than any other marriage of mode and mission.

In other words, (a) rail and bus technologies are tools, and no tool is right for every job, and (b) multi-destinational networks based on connections are more productive than radial systems that narrowly focus on a single downtown.  Regular readers of this blog will find these conclusions obvious, but it’s interesting to see that this argument still needs to be made in the literature.

UPDATE:  Let me tease this apart a little further.  I don’t mean to imply that the work is redundant, but it does apply to a narrow range of cases, and it conflates “multi-destinational” with “rail” a little more than I’m comfortable with.

The authors’ focus is on four cities which they locate on a spectrum from “CBD-oriented” to “multi-destinational.”

  • Pittsburgh, which they identify as the most “CBD-oriented.”
  • Minneapolis, which they identify as transitional or hybrid.
  • Atlanta and San Diego, which they identify as “multi-destinational.”

These cities are all comparable in size, all have a mix of rail and bus, and all have some facilities for getting express buses out of traffic at least some of the time, ranging from the full busways of Pittsburgh to the freeway-shoulder operations of Minneapolis.

A CBD-oriented system (more commonly called a radial system) is one that views downtown as the sole destination of importance.  In such a system, people who aren’t going downtown usually have to go via downtown, whether or not this is on the way.  A multi-destinational system is one that tries to serve trips to many destinations all over the city.  If you live in Los Angeles or Manhattan or Paris or Berlin, this distinction will seem silly to you, because your city has been multi-destinational for decades if not centuries and your transit system adapted to that reality long ago.  But most American (and Australasian) cities had a period, generally ending around 1945, when they had a single extremely concentrated downtown — fueled, in many cases, by streetcar/tram networks that converged on it.  And at one time, it made perfect sense that this downtown would be the sole focal point of the transit network.

Since 1945, most cities have been becoming more multi-destinational, with more important destinations (employment, retail, leisure, etc) scattered all over the city.  Transit agencies were generally slow to adjust, especially since downtown tended to be where they were most appreciated and where the pre-car development pattern made it easy for pedestrians to get to them.  But over time, it’s been necessary to adjust to a multi-destinational pattern in order to remain relevant to the life of the city as it is now.  The paper suggests that of the four cities studied, Atlanta and San Diego are relatively far along on that path, Pittsburgh least so.  (This seems to match Alan Hoffman’s observation (here, page 67) that despite the introduction of busways, the Pittsburgh network has changed relatively little for a long time.)

Note that the important distinction here is not that the network infrastructure is more or less CBD-oriented, but that the thinking of the transit agency is.  All four of the cities studied have CBD-oriented transit infrastructure that suits their CBD-oriented history, but they have thought about their networks in different ways.

By comparing the experience of these four cities, the authors find that the most effective system is not the CBD-oriented but the multi-destinational.  Needless to say, your mileage may vary; it depends on how CBD-oriented your city still is, but even a city as CBD-oriented as Portland had great success with a multi-destinational network.  Most of the major network redesigns I’ve done have been about helping CBD-oriented systems still meet their CBD need while also being relevant to a wider range of destinations.

My only quibble is that multi-destinational systems don’t have to mean “rail and bus working together” because you can do the same thing in smaller or pre-rail cities by designing an all-bus system to work just the way a good bus+rail system would work.  I was the lead planner on a redesign for San Antonio around 2001-2, shortly after their voters had rejected light rail.  We did what we could to create a connective frequent network given that they only had buses to work with.  Following Portland’s model, we did this with a mixture of high frequency grids in the denser inner city and trunk-and-feeder systems in the outer suburbs.  As a side effect, that project helped to intensify and simplify services in a concentrated corridor (Fredericksburg Road) where they’re now planning Bus Rapid Transit, and light rail is being talked about again.

Portland, too, did it with buses first.  Their multi-destinational route network (including the frequent grid covering the inner city and the trunk-and feeder structures for major outer suburbs) all were put in place by 1982, four years before the first light rail line opened.  Rail sometimes leads, but sometimes the result of good multi-destinational network planning, not its cause or starting point.

22 Responses to Bus vs Rail, an “Oversimplified Comparison”

  1. anonymouse December 13, 2009 at 1:52 pm #

    Only tangentially related, but it seems like BRT was the wrong tool for the job in the case of LA’s Orange Line. The MTA is now running a new supplemental service, Route 902, to connect Van Nuys Blvd to the North Hollywood Station, and relieve some of the load on the Orange Line at rush hours. Rather than using the fancy expensive busway, though, the 902 will run nonstop on Burbank Blvd.

  2. David December 13, 2009 at 5:06 pm #

    Funny, I haven’t found it too obvious reading this blog. I’ve seen excuse after excuse given as to why Ottawa’s BRT is not working and what Ottawa should do to “fix” the unfixable in the face of overwhelming evidence that just keeps piling up like snow at municipal snow dump in winter (as an aside, we’ve had our first snow storms in Ottawa, and, naturally, a few artics got stuck in it, blocking other buses) but never an admission that BRT is the wrong tool for the job in Ottawa, whereas the philosophy espoused by the study above makes it pretty clear (“a rail transit backbone and a multidestination service strategy”) that light rail should replace BRT on the Transitway.

  3. Ed O December 13, 2009 at 8:32 pm #

    Jarrett, not having read the paper, I can’t say whether the authors’ conclusions are obvious – or if your interpretation of the conclusions from the abstract is reasonable. Do you find the ongoing need for work on this topic ‘interesting’ because you believe it’s redundant; or because the knowledge on how to structure and operate multidestinational networks just isn’t getting through to planners and decision makers?

  4. J December 13, 2009 at 8:37 pm #

    I find the two above comments amusing. The first talks about how the orange line is bad, the second, how only BRT acting as a feeder is good. Guess what: The Orange Line feeds into the rail backbone (red line)!
    As for the new supplemental service…ehm, doesnt that show that BRT was a huge success if its running over capacity? I also dont understand why it’s not being routed via the exclusive lanes…

  5. Dan Wentzel December 14, 2009 at 7:33 am #

    The Orange Line isn’t “bad”, it just needs to be upgraded to light-rail. It’s already got the light-rail stations.

  6. Pantheon December 14, 2009 at 11:19 am #

    I still think Portland needs to rethink its bus system in favour of a more multi-destinational model. The bus network on the eastside is inadequate given the population growth and increased retail presence there.
    To be very specific, it is quite silly that there is only one bus line that connects the entire NE area to the SE (#75). (I am not counting the #6, because it touches the SE neighbourhood in only the most tangential fashion on its way downtown). If you are in the Alberta St. neighbourhood (an up and coming retail area) and you want to take a bus to the SE, you have to walk all the way to 42nd street because that is the only bus that will take you there. All the other bus lines go to the CBD.
    Considering that there is a lot of retail on the eastside, I imagine there are a lot of people who live in the SE and work in the NE, or vice versa. Not to mention that many may have friends or want to visit a restaurant once in a while in the other neighbourhood and imbibe freely without having to drive home (or connect in the CBD). That Portland has not updated its bus network in the last, oh, 30 years to reflect this reality is seriously offensive.
    Part of my opposition to the MAX system is that it reinforces the radial CBD-oriented approach even more, not only because they all go the CBD, but also because for the most part they do not serve any interesting destinations on the way to the CBD.
    EngineerScotty wondered a while back why I was so opposed to the MAX system, and this is a big part of it. I would be much more supportive of MAX if I felt Portland was taking a more balanced approach to things, rather than neglecting the bus system even as they continue to build shiny new rail lines out to the ‘burbs. Not to mention that I am also greatly opposed to parking lots at rail stations for the most part as I feel it only strengthens the automotive culture even more and discourages or even eliminates the possibility of TOD. But then I don’t want to get into too much of an oversimplified bus/rail comparsion here, or rehash an old debate ad infinitum. My central argument is about the multi-destinational vs. radial approach, regardless of whether it is rail or bus.

  7. Alon Levy December 14, 2009 at 12:19 pm #

    J: the problem with the Orange Line is that the capacity is so low that despite having low ridership, it’s running over capacity.

  8. EngineerScotty December 14, 2009 at 1:27 pm #

    Pantheon.
    Rather than raise any objections, a couple questions for you:
    1) Which routes (between SE and NE) would you like to see added or expanded? A 28th/33rd route? 39th/42nd? 52nd? 82nd (PDX to CTC?)? 122nd? Something further out? Something else?
    2) Which “interesting” destinations (I put the word in quotes because what is interesting to you might not be interesting to others) aren’t presently being served by MAX?
    3) What level of balance (I assume between urban and suburban transit needs) is appropriate?
    And a few comments.
    One problem with north-south service on the eastside (broadly speaking, between downtown and I-205) is that there aren’t very many contiguous north-south corridors. There’s 82nd, which gets frequent service already. There’s 39th (42nd north of Hollywood), which does too. All the other major north-south streets are fragmented, and only arterial in spots–and TriMet generally doesn’t like to run busses in neighborhood streets (and gets blasted by the neighbors when it tries).
    The park-and-ride topic (i.e are they good, as they reduce driving; or are they bad, as they don’t really encourage auto-independence) is an interesting one which Jarrett might consider blogging about.
    One of the future mass transit corridors in TriMet’s plans is essentially Clackamas to Washington Square via Lake Oswego (crossing the Willamette, likely, at a new transit-only bridge between LO and Milwaukie). Such a thing is a long way off, but that route, you’ll notice, doesn’t touch downtown. Improvements to the Tualatin/Beaverton corridor, now poorly served by WES, are also on the radar.
    I do think that Tri-Met needs to get a more stable funding base, and a few ideas that it has floated (such as bonding its payroll tax revenue) are idiotic in the extreme. OTOH, MAX moves a lot of people–it ain’t as though the trains are running empty most of the day, so I’m not entirely sure that expanding transit service to the ‘burbs vs improving inner city service, is entirely an unreasonable thing to do. My biggest complaints with TriMet concern some egregious tactical blunders, not its overall strategy.

  9. Jarrett at HumanTransit.org December 14, 2009 at 11:31 pm #

    Pantheon. I think you have to count Line 70 on 11th-12th, which you may see extended further north into NE sometime soon. As for Line 6, I’m afraid its convenient SE segment may be blown away when the streetcar opens there.

  10. M1EK December 15, 2009 at 9:42 am #

    The CBD service issue discussion above, as is usually the case, ignores the fact that transit, delivered well, can help restore the CBD’s rightful place as the core of an urban area. IE, you can choose to redesign your transit network to further subsidize employment sprawl – but that’s just going to lead to even less efficient transit and land-use. Or, you can build rail transit that hits some suburban employment centers but delivers superior CBD service – and in the long-run, provide employers with strong incentives to relocate back to the CBD – which is the obvious win.

  11. J December 15, 2009 at 11:54 am #

    Alon, there are many ways to increase capacity then. Increase frequency (I just looked at the headways, they arent great). Use longer buses (bi-articulated). Run buses as trains (attach a second bus to the first, only one driver, its done in switzerland). No need to spend money laying rail and electrifying the line.

  12. Alon Levy December 15, 2009 at 12:44 pm #

    Electrification is good in itself, given LA’s air quality issues.
    As for running buses as trains, it’s interesting. Do Swiss cities stick two artics together? Or do they use guided buses?

  13. Pantheon December 15, 2009 at 1:29 pm #

    EngineerScotty,
    Answers to your questions:
    1) I find it is often better to think of transportation in terms of goals to accomplish, rather than specific routes. At some point, transit professionals like Jarrett have to sit down and make up routes, but those routes should be informed by the goals of mobility and access that a community has identified for itself.
    I believe the Eastside should be thought of as a residential area with five areas of conentrated commercial activity. They are N Denver Ave, Lloyd Center, Alberta, SE Belmont, and SE Hawthorne. Very roughly speaking, Alberta from 6th to 30th, and Belmont and Hawthorne from 10th to 40th. Belmont and Hawthorne are so close to each other that they could be condensed to one, which we will call Belmont-Hawthorne. So that gives us four areas.
    My goal is that everyone who lives on the Eastside should be no more than a 7 block walk from a frequent bus line going to each of the four commercial areas. This would mean that such routes would be spaced no more than 14 blocks apart. In other words, Alberta, Denver, and Lloyd Center should have feeder routes spreading out all over the SE, spaced approximately 14 blocks apart. Similarly, Belmont-Hawthorne should have feeder routes spreading out all over the NE. Feeder buses that serve Alberta would continue on to Denver, and then to St. John’s. There should also definitely be a bus that connects Alberta to Belmont-Hawthorne directly. Note that buses in the NE basically already feed Alberta and Lloyd Center, and buses in the SE already basically feed Belmont-Hawthorne. Note also that as you go further out these buses might be more heavily spaced out. I just don’t know the Eastside beyond 82nd so I can’t comment on it.
    2) Interesting destinations are defined as core areas of commercial activity as described above. Two of the five are currently served by MAX, though note that you can get to Denver by bus from downtown just as fast, so the fact that it happens to be served by MAX is basically irrelevant insofar as considering MAX service an improvement over bus.
    3) That is a very difficult question for me to answer. Should it be thought of in terms of dollars invested? Some other measure? I don’t know. But I don’t think you can argue that it is currently balanced in any way. All of the investments over the last 30 years have gone into rail, and the bus service is actually less frequent than it was 30 years ago.
    It is true that there aren’t many contiguous North-South corridors. But who cares? Where is it written that buses must travel on the same street the whole way? And yes, of course the predictable crop of NIMBY’s will pop up to protest any improvement in transit service. But again, who cares? There will always be people who don’t want transit in “their” neighbourhood, whether it is bus, rail, or something else. America is the only country in the world where anyone would seriously consider the argument that there shouldn’t be bus service because a few NIMBY’s don’t want it, but that is indicative of a larger problem with America where there is too much emphasis placed on the rights of the few, and not enough on the rights of the many.
    I have a problem with your argument that the MAX is necessarily a good investment because it carries a certain number of people. I think we need to be very careful when making arguments about the efficacy of transit networks to be sure that they are not circular or self-fulfilling. Tri-Met has invested billions in rail over the last 30 years, and none in bus. So it stands to reason that MAX ridership has increased while bus ridership may not have. MAX ridership will increase even more when the Orange line gets built. That doesn’t mean it is a good investment. It is an apples-to-oranges comparison because we don’t know how many people the bus system would serve if a similar amount had been invested in it instead of rail. The question should not be “how many people does MAX serve?”, but rather, “is this the best way to move them around?” Or, “could we have done it better a different way?”. Hell, I spent the weekend in Seattle last month and noticed the Monorail was packed. Does that mean it was a success too?
    I think we need to be honest about what the MAX really is. It is a hodgepodge of different kinds of transit with very different goals, and that is a real problem. If someone asked me “what is MAX?” I couldn’t answer in one sentence. I don’t have a mental image of what the MAX is the way I have a mental image of what the Toronto subway is, or what the Vancouver Skytrain is. The MAX is by turns a commuter rail system with parking lots (Green, parts of Blue), a commuter rail system without (other parts of Blue), a street-running light rail line (Yellow), and a streetcar (downtown). The system was designed in such a half-assed fashion that it is basically many different modes of transit, all put together in a patchwork way. It doesn’t have a consistent brand image, and it is the only rail transit network I have seen that I can say that about. The description of it as “light” rail is also a little bit deceptive. In terms of how it actually functions, it is more of a heavy-rail system in light-rail drag – a bunch of suburban commuter lines with parking lots going express to downtown, a la Sounder in Seattle or Toronto’s Go.
    When you say “I’m not entirely sure that expanding transit service to the ‘burbs vs improving inner city service, is entirely an unreasonable thing to do”, the problem can be summed up with one word you used: “vs”. The mere fact that we are using that word to describe this situation is problematic. It shouldn’t be an all-or-nothing proposition, and transit shouldn’t be used to pit groups of people against each other. That is really what I mean when I say transit investments should be more balanced.

  14. Pantheon December 15, 2009 at 1:51 pm #

    Jarrett,
    You are right. I forgot about the #70. And as for the #6 segment being blown away, that is yet another reason for me to be against the streetcar.

  15. EngineerScotty December 15, 2009 at 2:56 pm #

    Pantheon,
    There are many “hubs” of commercial activity on the eastside, even if we limit ourselves to those west of I-205, beyond the one you list. Somehow, your list excludes the Hollywood District, Burnside west of Laurelhurst, the entire length of Powell, the entire length of 82nd, Lents, etc. If we venture a bit past I-205, we can throw in places like Gateway, the Mall 205 area, Airport Way, and so on. Many of these are also important destinations for transit, some better served than others.
    Not to be rude–but what you have described is a transit system to enable yuppies and the artsy crowd to get to the trendy neighborhoods and hot-spots quickly. 🙂
    I agree somewhat that MAX is a bit of a hodgepodge, in that different levels of service are provided (metro-like service in much of east Portland and past Beaverton; dang-near-streetcar-slow downtown). I’m not sure that this is really a problem, with the exception of people having to make crosstown trips (for which the downtown segment is painfully slow). This is probably one reason that TriMet is considering the LO/Milwaukie crossing mentioned previously–a downtown bypass. I don’t care much about “brand image”, I suppose. As far as it being a commuter line, I would disagree–commuter lines connect suburbs or exurbs with downtowns and stop infrequently, whereas MAX is stopping all along the line even in the fast parts.
    The Monorail in Seattle is as much of a tourist attraction as anything else–and it is successful at what it does, moving people from Seattle Center to downtown and back. Would I base an entire system on monorails (or recommend building one at all, unless for very specific applications?) Probably not.
    Transit, I don’t think, IS being used to “pit people against each other”–TriMet isn’t trying to pit anyone against anyone. Certain local governments like to grumble about getting their share, and inner-city residents will defend bus routes vigorously. But like most agencies which require an operational subsidy, adding service requires money rather than generating it; and so there is the question of how to spend the dollars best providing service. And the question of WHERE to provide service, and HOW (local bus, MAX, streetcar, BRT, something else) are fundamentally entangled.

  16. Pantheon December 15, 2009 at 7:02 pm #

    EngineerScotty,
    “What you have described is a transit system to enable yuppies and the artsy crowd to get to the trendy neighborhoods and hot-spots quickly”. Actually, that sounds more like a description of the Streetcar than what I am proposing. With the exception of the word “quickly”.
    Burnside and Hollywood could be included as stops along the way for some of the routes I am proposing. Although I hardly think those neighbourhoods rank with the ones I mentioned. It is true that I excluded Powell Blvd., 82nd Avenue, and Lents. But I have never heard anyone express a burning desire to, say, visit a restaurant in one of those places. I don’t know, maybe I’m hanging out with the wrong crowd.

  17. Jarrett at HumanTransit.org December 15, 2009 at 7:24 pm #


    Pantheon.  Good multi-destinational design avoids futile and divisive debates about which centers outside downtown are the most important.  A good grid system allows you to from anywhere to anywhere with a simple L-shaped trip using one transfer.  That's what Portland's eastside grid was trying to be when it went in in 1982, but it was never funded properly and now has less frequency than it had then.

  18. Pantheon December 15, 2009 at 9:03 pm #

    Jarrett,
    Fair enough, but I don’t agree that Portland’s eastside network is a very good grid. There is a huge gap in the inner eastside without any full-length north-south service. The #75 on 42nd/39th is the only full-length route (#6 stops at Hawthorne, #70 stops at Lloyd Center). After the #75, the next full-length one is the #71 on 60th. So that means you can walk 60 blocks and encounter exactly one true north-south route. That doesn’t sound like much of a “grid” to me.

  19. EngineerScotty December 15, 2009 at 9:20 pm #

    Pantheon–
    the above description is a bit puzzling, because the #71 runs on TWO N/S corridors, in a sort-of-horseshoe shape. Its eastern leg is on 122nd (60 blocks from 42nd), the western leg runs on a variety of numbered streets, changing often due to the discontinuity noted above. I’m sure you know this, of course–this is for readers not familiar with TriMet.
    One problem with this bus is it isn’t frequent service, and it’s not very useful for long trips, especially on its westside leg, due to the snaking around. But it is there.
    But between 39th and 82nd, the rough 52nd/60th/57th corridor is the only real corridor for bus service, with large swaths of residential streets (neighborhood collectors and locals) in between. Between 60th and 82nd, Mt. Tabor is an obstacle for transit, as the street grid doesn’t traverse it.

  20. Nathanael December 22, 2009 at 7:19 pm #

    “by designing an all-bus system to work just the way a good bus+rail system would work”
    You oversell your case. It can never work *just* the way a good bus+rail system would work, and if you tried to do that, it would be just as expensive.
    You should have said “approximately the way a good bus+rail system would work”.

  21. Aquaria April 14, 2010 at 10:04 pm #

    Now I know who to blame for San Antonio’s wretched scheduling that routes everyone through downtown, whether or not we need to go there. It’s ridiculous that I must go 15 miles southeast then 15 more northeast to go what is only 16 miles across from where I actually am.
    But that’s not all! None of the routes crossing the major streets meet up–the big routes will run 5-10 minutes before the metro feeder routes can get you to the big route (or vice versa–it’s never in your favor if you live on the NW side) and then you have to wait 30-55 minutes for the next bus to arrive. Routes get cut off midway through or end for the day, always just before you need that very route–why? Who knows?
    It takes me 2-3 hours most of the time to get from the NW side of SA to the NE side or vice versa, even in “peak” times with frequent service. That’s just stupid. I don’t have a life because I must spend 2-3 hours using VIA to get to work, 9 hours getting to and from the bus stops + working + lunch, and another 2-3 hours using VIA to get home.
    Look up how long it takes to get from Perrin Beitel and Wurzbach Pkwy to Clark High School if your workday ends at 7.30 a.m. Go ahead. See what it takes to get home, how long you must wait before you can get a bus that gets you home at a reasonable time. Then explain why I shouldn’t strangle all urban planners and fix the schedule myself. I can’t mess up VIA’s scheduling any worse than it already is!
    Unless you live inside Loop 410, VIA is a ridiculous, time-wasting bag of frustration that didn’t need to be that way. It would have more riders if it wasn’t such a pain to use. Heck, long before I was without a car, I was willing to invest a half hour extra each way not to have the frustrations of commuting to work. But VIA just won’t cooperate, thanks to you and whatever other morons came up with this pathetic excuse for bus scheduling.
    Thanks for nothing in making our city such a nightmare to get around for suburban public transit users.

  22. Jeb March 24, 2012 at 8:47 pm #

    I’m not quite sure I buy the idea that MSP is transitional. While there are ways to go places without hitting downtown Minneapolis, try going somewhere without going through either downtown Minneapolis, St. Paul, or Mall of America. It’s difficult, and most of the transit trips I’ve taken there require stopping at one of those three places.