# Thoughts on Brisbane Metro
Date: 2023-08-10

*Brisbane’s busway network is a victim of its own success. The “Metro”
project, while misleadingly named, is what’s possible as an incremental
upgrade.*

# How did we get here?

Brisbane’s main surface-level transport corridors were mostly
established by the middle of the 20th century. Queensland Rail train
lines covered some parts of the city, while Brisbane City Council trams
(generally running in the centre of the road, mixed-traffic) covered
much of the rest. In the 1960s, the trams were replaced with buses,[1]
many of which run the same routes today. In the early 1970s, the SE
Freeway (M3) route was developed with the Captain Cook Bridge opening to
traffic in 1973.

The 1997 [*Integrated Regional Transport
Plan*](https://web.archive.org/web/20110316094603/http://tmr.qld.gov.au/~/media/1008ff20-a4b7-4a18-89df-10c19d3348d6/pdf_irtp_part01.pdf)
proposed busways (with grades suitable for light rail) along the SE
Freeway to the Logan Hyperdome, to Capalaba via Carindale and Old
Cleveland Rd, and to Carseldine via Chermside and Gympie Rd. These areas
of the city are not served by QR heavy rail, and so were/are in need of
a dedicated public transport right-of-way.

The Brisbane busway operational concept is an “open network”: buses
collect passengers on suburban roads, then enter the busway for a
quicker trip to the city without passengers needing to transfer. Busways
were seen as a good incremental solution because sections could be
staged as needed or where possible.

The first part of the busway, from South Brisbane to Woolloongabba, was
delivered in 2000. In 2023, the busways extend south to Rochedale, east
to Langlands Park (with “transitway” part time bus lanes being added
further east), north to Windsor (with a non-contiguous busway tunnel
under Lutwyche and more transitway being added to Chermside). Extension
further south to the Hyperdome is about to happen alongside motorway
works.

It’s important to note that building the sort of dedicated right-of-way,
grade-separated busway Brisbane has is not cheaper than rail-based
options. What a busway *does* permit is deferring capital investment on
sections which would need to be there from the beginning for a
rail-based option, possibly at prohibitive expense.

Not in the *IRTP* — but very successful — is the western half of the
“Eastern Busway” to UQ Lakes, which has greatly improved access[2] to
the University of Queensland from the other side of the Brisbane River.
UQ is now the second-largest PT destination after the CBD itself.

For more detail, see [Tanko & Burke 2013, “How did Brisbane Get Its
Busways?”](https://australasiantransportresearchforum.org.au/wp-content/uploads/2022/03/2013_tanko_burke.pdf)

# What’s the problem?

The inner part of the busway from Mater Hill to the city became very
congested by the 2010s. The most visible trouble points are Mater Hill
in afternoon peak (as that station has short platforms) and queuing
across Victoria Bridge[3] and the Grey St intersection in either peak.

# What’s the solution space?

## Reverse branching

Many all-day trunk “BUZ”[4] routes (which, in the south and east of the
city, run via Mater Hill) have peak-only express counterparts
(“Rockets”) which run to the city via the Captain Cook Bridge. This
diverts CBD patronage away from the most congested section of the SE
Busway, between Mater Hill and the city. On those terms, it’s arguably a
success.

The main negatives of reverse branching are of course the hit to network
legibility and that frequency is cut in half for a major set of
destinations. When you’re going to Mater Hill, South Bank or the
Cultural Centre, the Rocket service is one that you have to remember
*not* to catch, or at least transfer from.

Only about half of the 300-ish buses through the Woolloongabba junction
in peak hour run via Mater Hill. This means the effective “stopping”
capacity of the busway is probably at or below 120 buses per hour. Above
that, it gets overly congested because there’s not enough platform
space.

## Light Rail

The busways were originally designed to have light rail laid on them.
It’s not clear exactly when this approach was given up on but there are
certainly parts of the busway today which wouldn’t support conversion.

A system where all the major corridors were light rail would almost
definitely be better from a capacity and passenger-experience
perspective than what we have today. The main problem with light rail is
“getting there from here”. Conversion to light rail would of course
require laying tracks on the busway (or perhaps in some places making
new corridor) but that’s only the beginning.

Matching the passenger capacity of the stopping routes via Mater Hill is
not that difficult in isolation. A Gold Coast size tram (the length of
the platforms at Mater Hill!) running every two minutes should be
sufficient. But full conversion would presumably mean replacing the
reverse-branch expresses too; and “tram every minute” operation would
surely push the limits of reliability. Lengthening Mater Hill station
would allow for longer trams and would surely be worth the expense at
some point.

That’s assuming tram-only operation. The busway platforms are designed
to allow for several buses stopped at once, and for buses to drive
around each other. A tram has to wait for the platform to clear. For
this reason it seems likely that mixed-mode operation would have *lower*
capacity than either mode running on its own.

The core of the busway system (especially at King George Square) has
routes from all over the city, so upgrading any one corridor still
involves mixed running in the core.

Because of the busway’s “open” operation, suburban stations are not
currently designed[5] to support trunk-and-feeder transfers. Substantial
works would presumably be required to allow for more of that.

On corridors with the patronage to support, say, 10-minute tram service
or higher[6] it would of course be better to extend the tram lines,
reducing the need for in-corridor bus-tram transfers.

Conclusion: It’s difficult to upgrade to Light Rail incrementally,
because of the issues with running mixed-mode and the interconnectivity
of the busway network.

## “Brisbane Metro”: longer buses

Fundamentally, the “Metro” project is about running longer
bi-articulated buses. This is an incremental improvement: there are more
passengers per vehicle, but the vehicles can still “play by bus rules”
in terms of operational flexibility.

The two initial Metro routes will directly upgrade two existing busway
routes: the 111 between Eight Mile Plains & Roma St stations, and the 66
between UQ Lakes and RBWH stations.

There will be some very limited network reform where minor bus routes
are terminated at suburban busway stations (probably under 20 buses/hour
in peak through Mater Hill). It also gives political support to other
(though still largely cost-neutral) network reform which puts several[7]
all-day not-quite-a-BUZ routes on the Captain Cook Bridge. Finally, with
new vehicles for the upgraded routes, their existing vehicles (which are
often themselves articulated) can be deployed elsewhere.

The Lord Mayor has also expressed intent to expand the system so that it
covers all the “busway” corridors. Since the vehicles are unlikely to be
run in general traffic lanes (for several reasons), support for Metro
expansion should also mean support for on-road Bus Rapid Transit lanes.

The project previously also proposed a major improvement at Cultural
Centre with via-South-Bank buses getting to go under Grey St. This has
been deferred indefinitely following disagreements between state and
local government. However, taking cars off the Victoria Bridge has
already allowed for intersection improvements at Grey St and the
Melbourne St busway portal (i.e. fewer phases = more busway time).

I can’t seem to find project cost breakdown by specific elements but it
seems likely the single most expensive element of the project is
actually the Adelaide St tunnel. This largely replaces a very nasty turn
between the Queen St and King George Square busway stations (including a
one-way-at-a-time section!). It’s unclear whether the new tunnel could
take a 43 metre tram as modelled above, but if it can’t then there’s
surely no hope for the existing turn either!

# Is it the best solution?

It’s not ideal, but it’s probably better than nothing. There’s a
substantial question around whether it represents any kind of value for
money and what the further upgrade paths are from here. Personally I
think that the major civil works being done on this project would also
be necessary for any sort of light rail upgrade, so in one sense they’ve
been brought forward. The other alternative is to build a new parallel
corridor, presumably as a light metro system similar to e.g. the
Vancouver Skytrain, which would take over the core baseload demand.

But fundamental transformation has been quite deliberately avoided.

*First published: 2023-08-10*

[1] “This has made a lot of people very angry and been widely regarded
as a bad move.”

[2] <https://humantransit.org/2014/07/brisbane-a-city-transformed-by-a-bus-bridge.html>

[3] <https://www.flickr.com/photos/danielbowen/6305218567/>

[4] Bus Upgrade Zone

[5] Garden City bus interchange being located above Upper Mount Gravatt
busway station is about as close as it gets. Woolloongabba and
Springwood are also OK.

[6] An ideal full car lane (following the “two second rule” and about
1.2 passengers/car on average) is about 2160 people/hour. When we
introduce an exclusive tram lane, that ought to not represent a capacity
decrease.

[7] The 125, 175 and 185. The corridors for all three routes will
benefit from the frequency and legibility boost - with more funding,
ideally all three would be BUZzes.

