Rapid Bus Fact Sheet


"Rapid bus" as proposed by Capital Metro seems to be an attempt to develop a "bus rapid transit" system for the urban core of Austin. This page will explain some of the common features of "bus rapid transit" in theory and in practice, and compare to what Capital Metro is proposing for the primary route (the Lamar/Guadalupe corridor).

Bus Rapid Transit

Developed by the Federal Transit Administration as a new, highly preferred alternative, bus rapid transit involves some combination of many individual efforts to enhance bus service. The model project for BRT is the city of Curitaba, Brazil; in which major arterials throughout the city have bus runningways in the median, with train-like boarding and other features designed to make a bus act more like a train.

Bus Rapid Transit, as defined by the FTA, can include very few to all of the service enhancements listed below.

Dedicated runningway

BRT systems can include a separated runningway (like a light-rail or heavy-rail track). Where done, this is usually implemented as a bus lane, or in the case of Miami-Dade's busway, a completely new paved facility. This BRT characteristic is the best contributor towards train-like performance, and most BRT systems when proposed include some degree of separated runningway. Unfortunately, during implementation a large number of those systems drop the dedicated runningway from their plans due to political opposition (see Honolulu). Most BRT systems end up running in shared lanes (some in HOV lanes shared with carpools; others in general-purpose lanes shared with any vehicles).

Signal priority

BRT systems can include the ability for the bus to affect signal changes at an upcoming intersection. Typically, this involves "holding a green" until the bus passes through the intersection (a current green light stays green longer than it otherwise would have) or "shortening a red" so the traffic in the bus' direction will get a green light quicker than they otherwise would have. This treatment is fairly common in BRT systems in the US even in implementation since its impact on cross traffic is fairly minor even with short bus headways. This treatment can improve the speed of the bus, as long as the other vehicle traffic on the road is below a certain threshold. (This does not work in backed up traffic, in other words).

Another form of signal priority, often called "queue jumping", allows a bus to get around a set of stopped cars at a signal. This can be accomplished with the use of a lane at the station which is reserved for bus use only, or for bus use and right turns. This treatment can provide a small improvement in speed if a particular intersection at a station is congested but the portion of the route following is not.

Train-like boarding

Most city buses (local and express buses) operate on the "board-pay" system, i.e., the passenger boards the bus and pays near the front of the bus, by dropping coins in a box or showing a card to the driver. With train-like boarding, the passenger pays at a ticket kiosk or machine, and then boards through a queue. Since this obviously requires more space for infrastructure and queueing at stops, this is fairly uncommon in the US. When implemented, it can provide slightly shorter stop times for the bus.

Limited stops

Although not limited to BRT, the concept of limiting stops (providing a longer distance between stops than on a typical city bus route) is nearly ubiquitous in BRT systems as proposed and as implemented. This can be achieved with normal bus routes as well, but is included since it is commonly thought of as a necessary prerequisite for BRT. Limiting stops provides higher speed in all applications.

Low floor and other vehicle characteristics

Many (most?) BRT systems also include low-floor treatments for the vehicle (instead of the bus having to lower for a wheelchair, the bus is already at a level at which it can be loaded, for instance). Also, in an attempt to lower operating cost, many BRT vehicles consist of two buses connected together, or an "articulated bus". Neither of these attributes affect speed more than trivially, but both can improve passenger perception of value.




Capital Metro's Rapid Bus system

Runningway

The Rapid Bus line proposed by Capital Metro runs in the normal vehicle lanes of Lamar and Guadalupe. It does not include any bus lanes or other treatments which could move the bus ahead of a long line of stopped cars. Queue-jumping at stations has been mentioned, but is not likely due to an effort to implement this system with minimal condemnation of adjoining properties. Therefore, if automobile traffic on Lamar and Guadalupe is slow due to congestion, the "rapid bus" will be slowed by the same congestion.

Signals

The Rapid Bus line proposed by Capital Metro does include the "hold the green" component of signal prioritization. However, due to the congestion along this route, especially on Guadalupe, it is unlikely to have much effect on vehicle speed.

Boarding

The Rapid Bus line proposed by Capital Metro does not include any changes to boarding of which I am aware.

Limited Stops

The Rapid Bus line proposed by Capital Metro does include the "limit stops" prerequisite of BRT. However, an existing bus route on this same corridor already provides this feature (the #101 North Lamar Limited). No improvement over current conditions is likely.

Vehicle characteristics

The vehicle proposed by Capital Metro for use on this Rapid Bus line is two short buses connected by an accordion-like device, allowing one driver to drive more passengers at a time. This vehicle's length is limited by the geometry of this corridor (and there are no plans to acquire any property even in tight spots such as Guadalupe at 29th). Operating larger vehicles could achieve a slightly lower operating cost than with the existing #101 bus. Passenger comfort may be slightly improved with a larger vehicle.



Conclusion

Speed Improvements

The #101 bus is much faster than the #1 (local) bus on the same route, but is much slower than a private automobile in this corridor. The Rapid Bus system is likely to be at least slightly faster than the existing #101 bus. Even in heavy traffic, at worst, the car may go nearly as slow as the #101 bus. The Rapid Bus system proposed by Capital Metro does nothing to improve the bus' standing against the car, since if one insisted on driving one's car down Lamar/Guadalupe even in heavy traffic, one could just tail one of these buses and get the same signal advantage which provides the only speed improvement in this proposal.

Reliability

The Rapid Bus system proposed by Capital Metro does not improve reliability compared to the #101 bus, since no dedicated or partially-dedicated runningway exists. If car traffic is backed up particularly far, the Rapid Bus will be stuck in it even with signal prioritization.

Comparison to automobile

If evaluating Capital Metro's Rapid Bus line compared to the private automobile, it is unlikely that any automobile driver will consider these improvements to be enough to make the bus a viable competitor to the car. After all, the #101 bus already exists on this corridor, and is not attracting a large number of "choice" commuters (apart from those whose "choice" is to pay a high premium for parking their car). There are two ways a transit line can become more competitive with the automobile - speed and reliability. If the average speed of a transit trip approaches that of driving, it may attract riders due to the other conveniences of transit (such as being able to read during one's commute). But even if the transit trip is slower on average, it can still compete if it provides a much more reliable trip than does the automobile (a trip which always takes 45 minutes may be more attractive than one which takes 30 minutes one day and 1 hour the next).

Unfortunately, Capital Metro's Rapid Bus line as proposed provides a trivial speed improvement, and no reliability improvement. It is unlikely to attract any new passengers to transit.