chicago: a new bus rapid transit plan

A Chicago-area planning nonprofit, the Metropolitan Planning Council, has released a plan for 10 Bus Rapid Transit within the City of Chicago.  The final report is here:  Download BRT TRB Report Final

The work, led by consultant Joshua K. Anderson, is admirably wonky.  It analyzes a huge range of arterial segments to identify those that appear best from a standpoint of both constructibility, demand, and nexus with livability values.  The report is a "screening" study, which means it seeks to narrow the range of possibility and encourage more detailed study of those that remain. 

Bus Rapid Transit is defined quite vigorously:

BRT is 4 defined by four main components: 1) dedicated bus lanes, 2) at-grade boarding, 3) pay-before-you-board stations, and 4) signal-prioritized intersections.

This definition is met by almost none of the things now called BRT in North America, or at least not continuously from one end to the other.  But screening is a time to be ambitious about such things.

Chicago brt map final
The 10 corridors that survive the screening are shown on this map.  They're a mixed bag: portions of segments, some of them maybe too short to be effective as BRT, but also two very long corridors, Western and Ashland Avenues, one of which is probably the most urgent BRT project in the city.

The study appears to be silent on whether these are envisioned as open BRT or closed BRT.  Open BRT means that the infrastructure can be used by bus lines that flow onward beyond it to other destinations.  To take an obvious example, an Irving Park BRT that ends at Ashland, short of the Red Line's connection opportunities and the high density of the lakeshore, is unlikely to be satisfying as a complete corridor.  But if it's an open BRT, usable by buses that continue east, it could well be useful. 

Unfortunately, a presumption of closed BRT, in which buses can't continue beyond the limits of the infrastructure, seems to be implied by the author's decision to discard super-dense Lake Shore Drive from the analysis simply because of the complexity of branching patterns that it requires; this assumption will have to be reconsidered in light of open-BRT best practice.

The study illustrates a common challenge in analyzing large, long transit corridors.  Many of the key issues, including available right of way and "livability" impacts, are segment-by-segment affairs; if these dominated the analysis, the result would be a huge pile of largely disconnected short segments, which could not deliver the intended outcomes.  So the author streamlined, discarding small segments and emphasizing larger continuous ones, which is quite right.

But issues of network integrity and completeness seem not to be fully considered.  The report needed to step much further back and describe the underlying geographic structure of Chicago, which determines the type of services that could be relevant to citywide mobility needs.

Except near the lake, Chicago is an extremely regular grid of arterials spaced 1/2 mile (800m) apart.  CTA follows this grid with a grid-pattern of long bus lines that attempt, as much as possible, to cover the entire length of an arterial all the way across the city.  This achieves the important goal of grid completion.  The purpose of each line is not just travel across that street but to complete a network in which people can travel from literally anywhere to anywhere else through a simple L-shaped movement:

Grid with trip

For more on the high-frequency grid principle, see here.  Obviously this structure only works, in its purpose to serve any origin-destination pair, if its constituent lines flow all the way across the grid to its natural edge.  This is the problem with many of the proposed BRT corridors in the report.

Not everyone sees this grid, because Chicago also has an overlying radial system of rapid transit, which runs along diagonals pointing toward downtown.  The two overlaid elements — radial trains and grid buses — work well together, but if you focus too much on the trains, which are mostly about going downtown, you miss the power of the underlying grid to complete trips on any origin-destination pair by a reasonably direct path.  (The report discusses "network integration" only in the form of integration with rail.  Confusingly, too, it gives heavy emphasis to connections with suburban commuter rail — whose poor frequency makes connection difficult — and little to the bus-bus grid connections that are the essence of the network's anywhere-to-anywhere versatility.)

Given Chicago's grid structure, and how well it already works, BRT needed to be understood as a system of grid accelerators, just like the Metro Rapid and proposed Wilshire subway in the similar grid of Los Angeles.  Obviously, if you can concentrate particularly heavy demand on a few elements of the grid, you can justify an overlay of much faster service, stopping only at the grid connection points every half-mile.

On that score, Western Avenue is clearly a winner.  It is the longest arterial in Chicago, running north-south the entire length of the city.  Its extreme length creates reliability issues on a local-stop service, which has caused CTA to break it into three lines thus reducing its usefulness for continuous movement.  BRT would be an opportunity to recombine these three segments to offer a service that would be understood as an intrinsic feature of Western Avenue over its entire length.   Western is also far enough out of downtown that the direct paths it serves are much faster than riding rail into downtown and back.  A vast range of trips between many parts of Chicago would find a Western BRT line useful. 

None of the other corridors identified in the study can match Western in the utility that arises from extreme length with lots of connection opportunities.  Ashland is obviously close.  Most of the other proposed segments are simply too short, and would be useful only as open BRT segments used by buses that run further.  Effective BRT has to serve long corridors, because the tradeoff that BRT requires of the customer — walk further in return for faster service — makes sense only for a fairly long trip. 

To sum up, the report is very useful and highly recommended.  But it misses (or at least downplays) two points that are missing in many similar studies, and that really matter:

  • Open or closed BRT?  They're totally different, and if you're not clear which you mean, it's impossible to envision the service patterns, and thus the mobility, that your proposal will offer. 
  • Integration with the total network, not just rail.  This requires seeing how the whole mobility flow of the city works, and how each corridor would contribute to that flow.  Localized analysis that asks where BRT would be easy to create or locally beneficial can easily lose this "forest" in its obsession with the trees.  Understanding this principle would have required a much firmer focus on complete corridors that traverse the grid and make many connections, rather than the small fragments that are frequently proposed.

Still, the report can do a lot of good, and bravo to the Metropolitan Planning Council for sponsoring it.  Chicago really needs to start accelerating its bus grid, especially on its busy, high-stakes, versatile corridors like Western.  I hope this study helps to move that along.


23 Responses to chicago: a new bus rapid transit plan

  1. tomtakt August 24, 2011 at 4:01 pm #

    Great analysis! You hit on most of my concerns about the study. That said, the report had a few distorting objectives in terms of a comprehensive transit planning study. The authors wanted to promote a showcase example for the US of what they call “gold standard” BRT, essentially what you referred to as closed BRT. I suspect they also wanted to promote relatively easy-to-implement options that would not face extreme challenges to quality implementation (non-compromising in elements that improve BRT performance).
    Viewed in the context of windy (read: highly political) Chicago, this may have been wise in order to push forward a project that would not be subject to difficult and out-of-the-local-comfort-zone types of trade-offs in order to include those gold standard design elements–essentially they wanted an easy-to-build recommendation. I think that may be wise considering that the value of a successful, exemplary pilot BRT line could be very useful for changing public perception.
    That said, I think that in terms of potential for picking up Gunmetal/pent-up rider demand, they are really missing the boat by not looking at connections between population concentrations and the radial urban rail network. Fortunately, BRT’s unique ability to incorporate open systems allows for service redesign later to improve the network without wasting the less-than-perfect (but good) initial investment.
    Fortunately, the City is onboard and has plans to roll out BRT before the end of Rahm Emmanuel’s first term. I’m happy as long as that happens and distracts from further implementation of the tragically designed Red Line Extension, which would sink a much larger and irretrievable in a mediocre-at-best rail alignment.

  2. jfruh August 24, 2011 at 6:18 pm #

    How do you implement open BRT if, on the BRT segments, you have pre-paid boarding? If you make things proof-of-payment, you have to have some way to get those tickets to passengers when they board the bus in BRT-zones. It can be done — Muni did in SF when I lived there in the late ’90s-early ’00s — but it does slow the boarding process down a bit.

  3. jfruh August 24, 2011 at 6:19 pm #

    (Ugh sorry that should read “board the bus in non-BRT-zones” above.)

  4. Jarrett August 24, 2011 at 7:21 pm #

    JFruh. I don’t see the problem. Where there are off-board ticket machines you use them to get a ticket. Where there are not, you pay the driver and he issues you one. Either way you have proof of payment.

  5. zefwagner August 24, 2011 at 9:00 pm #

    RapidRide in Seattle uses just such a mixed system, where riders at “stations” pay at the platform, while riders who board at “stops” pay the driver and get a proof-of-payment. I think it is very confusing because they chose to have stations and stops all along the line, and the overall stop spacing is not very wide. With Open BRT, on the other hand, I would think you would have pay-as-you-board in the outlying segments where the bus is more like a local and dwell times are not as big a deal. Once the bus enters the BRT corridor, it switches to wide 1/2-mile stop spacing and off-board payment. One trick here is branding to avoid confusion–they should be called A1, A2, A3, etc, rather than having entirely different numbers.

  6. zefwagner August 24, 2011 at 9:05 pm #

    I suppose part of the resistance to Open BRT is a fear that the operations side will be difficult to manage. If the BRT line has 10 minute headways, schedulers have to make sure the multiple tails enter the BRT corridor at precise 10 minute intervals, which can be tricky. As long as the tails go through uncongested areas and really focus on reliability, it could definitely be done, but I’m sure planners like the idea of a closed system with fewer opportunities for delay.

  7. Jarrett August 24, 2011 at 9:23 pm #

    Zef. The scheduling task isn’t as difficult as you suggest (and what you suggest shouldn’t be viewed as difficult anyway by a halfway competent scheduler.)
    While you obviously want best possible offset of buses in the open busway, and thus maximum possible frequency there, it isn’t an operational problem if two buses end up close together. In fact, during the peak, the throughput of large numbers of buses may be an important feature.

  8. zefwagner August 24, 2011 at 9:43 pm #

    I didn’t mean to suggest it actually would be difficult, just that in practice things can easily go awry. A couple years ago, the schedulers at King County Metro changed the schedule on the 71,72, and 73 expresses without communicating with the planners. The result was that often 2 or even all 3 buses would come at around the same time, with a long wait until the next batch. This got fixed, but it’s the kind of thing that seems to happen fairly often even at the best transit agencies. The schedulers are often focused on layover time and other details, rather than looking at the effects down the line as part of the network.
    That’s a good point that given enough frequency and the availability of passing lanes, it might be good to have multiple buses close together, since the not-so-full bus can pass the full one. That can help deal with overcrowding.

  9. Chris, Public Transport August 25, 2011 at 8:40 am #

    I think the lack of open BRT is a problem with Metro’s Rapid and Colored Bus Lines, with empty rapid buses at the end of line passing people waiting at a stop because they weren’t waiting at a rapid stop. Toronto style express buses would be better; they make local stops at the end of the route and then operate express during the main portion.
    Despite this, I’ve been told that ridership on the 110 corridor in LA has significantly increased since a special bus route called the Silver Line replaced the former routes that operated along it; almost all of these former routes now end at a transit center and have a forced transfer to reach downtown LA.
    The open/closed BRT question kind of relates to the route number question – the open BRT is by its nature more complicated, and would require well-thought out route numbers – while a closed BRT is simple and can be known simply as a color.
    Anyway, the CTA operates a sensible system, so I bet whatever they come up with will be sensible.

  10. Zoltán August 25, 2011 at 1:15 pm #

    @jfruh @Jarrett
    This is what happens on the proof-of-payment local stop trams in Helsinki. Most people have smartcards and can use the readers at every door, but you can purchase a ticket from the driver if you don’t already have one. I’ve never seen more than a couple of people needing to pay cash at any given stop, so it doesn’t really slow anything down.
    I believe the city would be well-served by implementing articulated buses on the busiest routes, and on those routes applying the same system as on the trams.
    Incidentally, in a very similar way, on the city’s high-frequency commuter rail system each train has a conductor that dispatches the train at centre platforms (away from the driver’s window), who stays in a single carriage marked the “ticketing car” and can sell tickets to those that need them. I view this as a good way of doing PoP on rail systems with many minor stations that don’t justify a ticket office.

  11. Jeff Wegerson August 25, 2011 at 1:20 pm #

    Thanks for your insight. You gave voice to my own un-articulated concerns about the integrity of the bus system grid as a whole. It means that even minor arterial streets require a decent frequency in order to maintain the quality of the system as a whole.
    I have used the Western corridor. I have boarded mid-north and traveled both via train connection and bus connection to get to mid-west. The timing is comparable. The speed on the train is lost in the extra time to go downtown, exactly as you say.
    For a while they tried “express” buses on Western. The only difference between the express bus and the normal bus was half mile boarding stops for the express. The time difference was a few minutes for five miles of travel.
    There does seem to be a local blind spot with regards to creating a bus only lane on LSD for BRT. I can see why they end the Irving Park BRT at Ashland, Irving after that point becomes very narrow. But to ignore the possibility of a connection to LSD and an Open BRT there is again an example of the local blind spot. I assume it’s a “be careful, don’t upset any drivers” mentality.

  12. Justin N August 25, 2011 at 4:05 pm #

    When I was in Chicago this summer I noted the appalling information provided about bus connections at rail stations. The only time my wife and I (as tourists) took the bus was when Google Transit suggested it- I never got a clear idea of how the buses flowed through the city. Finally, as we were waiting for the bus to take us back to the Amtrak station, the shelter we were at had a bus system map.
    Looks like that attitude about bus service is prevalent at CTA.

  13. david vartanoff August 25, 2011 at 6:03 pm #

    old timers will recall CTA dreamt of a Western Av crosstown L in the 50s. The need is greater as both jobs and housing have sprawled. As long as there is no real money for rail transit BRT is a good band aid. There is unused mainline ROW very close to Western which could be used as was done building the Orange Line to Midway.

  14. Beta Magellan August 25, 2011 at 7:19 pm #

    I’d say the big reason no LSD route was considered was because it would almost certainly involve getting rid of a general traffic lane—not a problem to me, but certainly a major political hurdle. Adding lanes is probably impossible since LSD is mostly bounded by parks, beaches and the “Inner Drive,” which provides local circulation for the high-rises lining road; even with converted lanes you’d probably need to reconfigure intersections to allow for bus-only ramps (I’m assuming a Brisbane level of service between various North Side points and downtown—there are probably sub-quickway improvements you could do on the Drive, but I doubt they’d save much time).
    @David—No offense, but using that ROW would be an awful idea. Although it parallels Western, the area around that line is fairly low density (in some cases disinvestment and post-urban renewal blight) and not terribly pedestrian-friendly, and the densest parts of the Western Avenue corridor are north of that ROW’s termination point, meaning the line would have to be in a subway. It’s a favorite fantasy project, but personally I doubt there really is the traffic density to justify the investment (I wasn’t a big fan of the Circle Line either, but at least it eased access to the Medical District, which has the highest employment density of any part of the city outside downtown).

  15. Josh Ellis August 26, 2011 at 2:12 pm #

    Hi everyone, my name is Josh Ellis, the project lead for this study by the Metropolitan Planning Council (in addition to Joshua Anderson, the lead researcher). Thanks for a lively discussion of our report and where it fits into the broader BRT discussion.
    For those of you that don’t know who MPC is, I think it’s important to know that we are not a transit agency, but rather a policy advocate in regional and community development issues in the Chicago area. That said, we see BRT as both a transit project and a community development effort, which informs many of the decisions we made throughout the paper. I think that’s a critical distinction.
    To address a couple of points here:
    – Lake Shore Drive was not considered simply because there is no opportunity for community development along what is essentially an isolated highway. We state very clearly in the report that some form of transit enhancement running along Lake Shore Drive (e.g. express bus, dedicated bus lanes, etc.) is likely warranted, but not consistent with our vision as BRT forming the framework for complementary public an private investment in station areas.
    – As to why certain BRT routes send where they do… as noted above, we strongly advocate for dedicated lanes for the full extent of the BRT route. In the Irving park example noted above, as well as in the far more egregious example of Garfield Blvd. (wherein the BRT route ends at Western, even though the street continues to Midway International Airport), the street is simply too narrow to include a dedicated lane eastward beyond Ashland. Surely the BRT vehicle could continue running in mixed traffic to the Red Line stop, or in the case of Garfield, to Midway.
    – As to open vs. closed, we simply didn’t feel it was necessary at this stage in Chicago’s discussion of BRT to be that prescriptive. Our goal was to demonstrate that BRT with dedicated lanes was possible in Chicago, but only possible on a small number of corridors, and that within that number of corridors, some would provide better connections to existing rail and other livability amenities than others. We want Chicago to set ‘gold-standard’ as the goal (acknowledging that in reality we may not be able to achieve that standard), and I think our report has successfully pushing the expectation of BRT in Chicago in that direction. Are ‘open’ and ‘closed’ both on the table? Yes, and it’s those kinds of questions that need to analyzed along Western and Ashland as part of the CTA’s Alternatives Analysis.
    – Lastly, as to the question of connecting to CTA and/or Metra rail… I frankly don’t understand the comment posted above about “missing the boat by not looking at connections between population concentrations and the radial urban rail network” when in fact that is exactly what we did. We prioritized routes and segments of routes by many factors, including population concentrations (and within that, populations living beyond walking distance of existing rail) as well as connections to both CTA and Metra. That’s stated very clearly throughout the report. As to whether connections to CTA are more beneficial than Metra
    because of frequency of service… 1) frequency of service can be altered fall more readily than location of stations; and 2) not everyone living in Chicago works in downtown Chicago, and not everyone coming to Chicago to work works in downtown Chicago, so improving connections to the suburban rail system helps a whole lot of people who don’t need to go downtown.
    Again, thanks for a great discussion, and I’m happy to answer any and all questions about the study, which I encourage everyone to read. I can’t reiterate Jarrett’s point at the outset enough, this “report is a “screening” study, which means it seeks to narrow the range of possibility and encourage more detailed study of those that remain.” Our goal was to narrow Chicago’s vision on practical/beneficial corridors, as well as to create an expectation for what BRT is and isn’t.
    Josh Ellis
    Metropolitan Planning Council

  16. Ben Smith August 28, 2011 at 10:17 am #

    While Chicago will definitely benefit from these new lines, they could probably greatly improve the performance of their current bus routes by increasing the stop spacing. From what I can tell, most routes have a stop spacing of about 1/8th of a mile, or 200m. If they increased that to 1/4th or 1/5th, even 1/6th, they could greatly improve the performance while still offering excellent local coverage.

  17. Beta Magellan August 29, 2011 at 2:39 pm #

    Off-peak, it often is around 1/4 due to skipped stops. Although there would definitely be some political pressure to keep them on every block or so (I remember seeing this in Milwaukee when railstitution or BRT was proposed along a major bus corridor), it might not be as big a hurdle as we imagine.
    A bigger problem, though, would be the possibility that this would lead to more paratransit service in the city—it might even be required by the ADA if the CTA were to increase its stop spacing. Paratransit’s typically quite expensive per rider—I know that the MBTA’s suffering from the fact that it can’t cut back its paratransit services, which are mandated by the ADA. Although I got the impression that much of the problem there came from paratransit in the more rural parts of the MBTA’s service area, if extra paratransit’s a precondition for stop consolidation I can see why the CTA would be reluctant to look into it.

  18. Wad August 29, 2011 at 4:56 pm #

    @Ben, Chicago’s famous grid is eight streets to a mile. Do local buses really stop every block?
    Also, many Chicago streets have bus service a half-mile, or four blocks, apart. Even limited-stop buses couldn’t produce a time savings.

  19. Beta Magellan August 30, 2011 at 7:25 am #

    @Wad—not consistently—they’re flag stops, but sometimes it happens. Very rarely it’s closer. when there’s a “Place” in between two streets (e. g. 54th St., 54th Place, 55th St.).

  20. Alex August 30, 2011 at 8:24 am #

    @Wad, it’s been a while since I rode a bus in Chicago, but Minneapolis has a similar 8 blocks per mile grid, and I can tell you on several routes (the 4, 5, 6, 14 and 18 come to mind) people typically flag stops every block for a mile or two out of downtown.
    I imagine the problem is worse in Chicago (most of them are).
    Curious about the ADA requirements for stops every 1/8 of a mile. Is that based on science or is it an arbitrary distance?

  21. Al Dimond August 30, 2011 at 1:10 pm #

    @Wad: The “logical” layout of Chicago streets for address numbering is 8 to a mile, except for the three miles south of Madison, where there are 12, 10, and 9 respectively. So Roosevelt (1200 S) is a mile south of Madison, Cermak (2200 S) is a mile south of Roosevelt, and 31st is a mile south of Cermak. After that it’s regular.
    The major streets are on a very regular mile grid, with secondary roads on a quite regular half-mile grid, and the side street layouts can vary a lot from neighborhood to neighborhood. Usually in at least one direction there are streets more often than every 1/8-mile. Older neighborhoods had the grid imposed onto them later, and often have slight offsets in parts of their grids. I don’t think all the minor streets have bus stops, but there are at least 8 stops per mile most places.
    But, for what it’s worth, the 9X and similar routes didn’t really improve things much. I was once on a regular Western bus with a rather aggressive driver that passed its “express” cousin, and in the 9 miles or so I stayed on it didn’t catch us again.

  22. Beta Magellan August 30, 2011 at 4:22 pm #

    @Alex—I think the spacing’s an ADA thing but rather a relic from when the trolleys were competing with the sidewalks.
    My question was whether ADA-mandated paratransit would have to pick up the slack if the CTA abandoned every-block stops, even if for something like quarter-mile stop spacing (common in Europe). I really have no clue.

  23. Scott Riedel December 17, 2011 at 11:09 pm #

    Wouldn’t it be better still to build a CTA rail line on Western Avenue that would intersect with the lines radiating out from the Loop (Chicago’s city center)?