Bus Rapid Transit – An Introduction

033Recently I completed a series of posts on Bus Rapid Transit (BRT). Although I had mentioned it as being complete, there should be a quick introduction for those unfamiliar with developing transit techniques.  Thus, this post will discuss what Bus Rapid Transit (BRT) is, and the main advantages/disadvantages to using such a system.

What is BRT?

BRT is, in essence, a way to use buses in the way we would think about using trains. By mimicking light rail type systems BRT can speed up travel times, improve reliability and improve the overall transit service along the route. This is done in several ways. BRT systems should have dedicated lanes, level boarding, off board fare payment/multi-door boarding, and special signals at intersections, these improvements all contribute to faster running times and higher reliability.

Dedicated lanes are often the hardest part of a project to get political support (see Red Line), but they are also the most essential portion of BRT projects. By dedicating lanes to buses, the buses no longer have to compete with normal congestion and traffic, and we can see this in the Twin Cities using the proxy of Bus-Only Shoulders. Bus-Only Shoulders have been shown to increase average speeds, reliability, and ridership.

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Boarding in a BRT system is meant to be level and use multiple doors, with fares paid for before boarding the vehicle. Level boarding prevents delays from buses kneeling, or using lifts to accommodate those with disabilities, or those who are less sure footed. By removing changes in height from the boarding process the system can board faster, be more inclusive, and be more reliable by not being delayed by individual passengers. Using multiple doors to board a bus is similar to how trains board their passengers, this system is already used by the University of Minnesota’s Campus Connector and express bus outbound trips. This method is faster than single door boarding, simply because there are more entry points into the vehicle. Pre-paying for fares also speeds up the boarding process, especially for cash fare patrons. If you would like to experience these improvements in boarding for yourself ride a train, then ride a heavily ridden local bus route (ex: Blue Line and the 16). When these steps are taken as a unit, no queue to enter ever forms, and every stop will take a similar amount of time.

Also like a train, a BRT’s buses should have some sort of advantage at intersections, either giving them the right-of-way or at least moving up the bus in priority against other traffic. This can take many forms, from signals being timed for non-stop trips between stations, to giving buses a head start, to simply preventing left turns when a bus is present. Signals again increase speed and reliability, and can be some of the most exciting technology that exists (it is being installed across the Twin Cities, mostly as a way to keep buses on schedule by holding green lights for just a few extra moments).

We already have trains, why do we need BRT too?

BRT uses buses, and pavement. We are good at buses and pavement, and they are cheap in comparison to trains and rails. Because of our existing infrastructure for maintenance of buses and roads, we gain the economies of scale from already having an expansive bus service and road network.


About nine lanes in total, as a surface road… we do this a lot.

BRT can be adapted and made to be more palatable than a train in some situations, such as the Orange Line in Minneapolis. Instead of dedicating lanes solely to buses, the lanes also serve carpools and people who will pay a toll. Rail projects, especially those that are going to be operating at a higher speed than a streetcar, need their own right-of-way simply because they cannot stop from high speeds as quickly as would be needed in congestion and other common occurrences on these roadways. This allowance for some infringement on the dedicated lanes can make projects more palatable to the driving public because they are not seen as taking away roadspace. BRT projects can serve entire corridors, not just a single route. When you build a train, you usually cannot drive a bus on the train tracks, that space is only for trains. Thus the improvement of building the line only benefits those that will use that line.

Sometimes buses do drive on train tracks, but it’s not often.

With BRT, a local bus that needs to travel along the corridor for a short while can still use the BRT improvements, as they would not be able to use train tracks, providing benefits to transit which might use the corridor but not the line.

So what’s the catch?

BRT does have some downsides, operating costs are typically higher than with trains simply because you need an operator on every bus, which can max out at about 80 passengers (even with standees and an articulated/accordion bus). Trains can be joined together, and train cars have higher capacities than buses, providing a more efficient allocation of labor.

People like trains. I will let this play itself out in the comments, but in the U.S. it appears that people prefer to take a train rather than a bus.

Remember how BRT can be made more palatable from above? Like the Orange line with letting carpools into its lanes? While that’s great for getting something done it removes a lot of the advantage that BRT gains from having these facilities. From not fully dedicated lanes, to not getting the lanes in congested areas (where they’re most needed), to not giving BRTs any lanes and instead relying on queue jumps at intersections, there are lots of ways to make your service less effective. This phenomena happens often enough it has been dubbed as BRT Creep. While the most common forms of BRT Creep involve the dedicated lanes, sometimes stations just become normal bus stops, prepayment is ignored on some or all stations, or a service is otherwise worsened to cut costs. This doesn’t typically happen with trains, because trains cannot be mixed with normal traffic, cannot kneel, and need conductors if they don’t have prepayment. When trains need to cut costs, you end up with fewer stations, a shorter line, or an alignment through a park instead of a dense urban environment. When BRTs need to cut costs, you end up with a new bus that’s painted a different color than the others.  This is why BRTs are hard from a planning and a policy perspective, there is so much flexibility that they can be watered down to the point that we get Arterial BRT, which really comes to slightly improved bus service.


It’s hard to justify a lack of a platform for a light rail station.

If you would like to revisit the evaluations of the Red Line, Campus Connector, or the BRT Scorecard, with this new information, please do.

Sources (not linked in above)

Frank Douma, Bus-Only Shoulders in the Twin Cities, University of Minnesota, Humphrey Institute, June 2007.

Bus-Only Shoulders – A Transit Advantage, MnDOT

Joseph Totten

About Joseph Totten

Joe is a graduate of Civil Engineering-Transportation and Urban Studies at the University of Minnesota, and has a masters degree from Portland State University. Born and raised in Saint Paul, Joe has worked with nonprofits and public agencies in MSP and Portland.

6 thoughts on “Bus Rapid Transit – An Introduction

  1. Steven Prince

    Nice post.

    One perceived downside of BRT is development potential. One important reason communities build LRT is to encourage development at the stops. BRT systems have lower infrastructure investments; the buses can be moved tomorrow; the stop locations can be easily changed; pavement can be converted to auto use.

    That may make property owners reluctant to invest in the concentrated development we want at transit nodes.

    BRT is a great deal deal from a cost perspective, but does it encourage investment the way (we assume) LRT does? Has anyone studied the U’s transit-way (The oldest BRT in town) vs. the Hiawatha Line for changes in development patterns or land values?

    1. Alex CecchiniAlex Cecchini

      I’d cheekily (and of course, predictably) ask how permanent the rail investments made at the turn of the 20th Century were.

      But more seriously, changing bus line routes, their stops, etc is incredibly difficult. How often do bus routes make meaningful changes in MSP, particularly within core city limits? Frequencies and hours of operation may change, routes downgraded when other investments (like LRT) come in, etc. If (and politically speaking, big if) BRT is implemented fully with full stations, raised curbs, dedicated lanes, and more, I can’t imagine that route being picked up and moved any more than a streetcar route, for example.

      We should view transit investments as primarily serving existing markets, with a priority further down the list to spur more development. With that in mind, there are plenty of markets today that aren’t going anywhere, and are actually growing like crazy on their own without rail or bus improvements. Or others that aren’t growing so fast but need significant improvement to transit service anyway, but we can’t serve them all with streetcars or LRT because we don’t have the money.

      I think the goals of the U’s BRT are completely different than the Blue Line LRT, and comparing them wouldn’t be a very good exercise. The campus BRT is meant to connect major points within the university, mostly for the students and staff who are already on campus. It doesn’t really run past much developable land (though there certainly has been plenty of development near the U anyway).

      Besides, what good is development potential if neighborhood groups don’t want it or re-zone anyway?

      1. Joseph TottenJoseph Totten Post author

        The investment in BRT is possible and likely if you do a good job with your system. (David Levinson posted about this in September https://streets.mn/2013/09/11/does-brt-have-economic-development-effects/)

        And BRTs should be built in a way that the conversion from buses to general auto is difficult (is this being done in the US? No, not really… we get the Red Line and Snelling Avenue instead…)

        Really, this more comes down to what I said I’d leave for the comments, the ridership seems higher for trains, it seems people like them more, exactly why has everyone stumped but we all have our own theories.

  2. Matty LangMatty Lang

    I agree–very nice post Joe. You’ve done a great job explaining the trade offs between LRT and BRT. However, on the point of long term costs you mention operating costs, but do not talk much about maintenance costs.

    Rail system rolling stock and tracks both have a much longer lifetime than buses and pavement. When shared use of the bus lanes is involved through BRT Creep, the pressure on the pavement is only increased and the lifetime reduced. My point is that it seems like the initial capitol costs of rail systems probably are not as outrageous as it’s often assumed when compared to bus systems over the lifetime of each set of infrastructure.

    Here’s a study that was done on the St. Louis metro system over a 10 year period that shows the rail system to be actually cheaper than the bus system on a per passenger mile basis:


    Regarding the question of a rail preference, I can say that I have a distinct preference for riding the train over the bus.

    1. Joseph TottenJoseph Totten Post author

      I’d agree. I think rail bias does exist because I am susceptible to it, buses often end up jerky and give me greater discomfort. Case in point; I have never fallen asleep on a bus while trying to keep myself awake.

      For the maintenance costs, I hadn’t seen it, thanks for the link. Shared lanes come down to further confusion… because then who pays? MnPASS could be great for the METRO Orange Line because it’s paid for by MnDOT, and I don’t know if MetroTransit pays tolls or not.

  3. Walker AngellWalker Angell

    Great post Joe.

    Preference for rail (LRT or Tram) is not limited to the U.S. Every European I’ve asked prefers rail as well. For riders rail is smoother, doesn’t rock side to side as much (or does so in a less annoying way), and has consistent routes for decades rather than days or weeks. While BRT requires people to climb up a ramp to the boarding level, trams are much lower to the ground. BRT also, I think, requires much larger boarding platforms than trams due to the height.

    Most trams are also less visually intrusive to people on sidewalks, produce much less air burst when they pass by (particularly those sitting in sidewalk cafe’s) and produce no local pollution.

    Rail is predictable compliments of the rail guidance. Two-way systems can be closer together and rail can pass closer to buildings and other objects. Pedestrians, bicyclists, and vehicles can operate closer to them and safer (and feel safer) because they know exactly where they will go and that they’ll not deviate more than an inch.

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