Rapid Bus Fact Sheet
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).
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
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
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.
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.
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.
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.
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.
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.
The Rapid Bus line proposed by Capital Metro does not include any
changes to boarding of which I am aware.
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
No improvement over current conditions is likely.
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.
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.
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.