Annex 4
Financial, Operational and Demand Comparison
of Light Rail, Guided Bus, Busways and Bus Lanes
EXECUTIVE SUMMARY
The purpose of this study was primarily to evaluate
the experience of existing light rail, guided bus, busway, and
bus lane systems to current plans for expanding the role of public
transport generally. The evaluation covers technical and financial
aspects, together with results of surveys (including new ones
carried out for the project) on the attitudes and judgements of
passengers and car users. In the final section of this summary
we outline a policy evaluation based on the study.
Existing and proposed systems
When studying existing and proposed systems
it is evident that light rail was and remains the mode in which
are invested the greatest aspirations for an expanding role for
public transport, especially in Europe, but also in the US. Bus
lanes are rarely provided with the extensive network of priorities
that would be necessary for them to fulfil their potential, except
in the centres of some capitals. So far there is no city in the
world which has implemented a full guided bus network, so the
experience is meagre. It is a matter of concern, for British current
thinking, that apart from Leeds, none of those other few cities
which built guided busways, have expanded them further. Busways,
however, have been built in a number of North American cities,
also in Brazil and Japan: in two cases which we visited, it was
clear that an important consideration was the availability of
existing rail, tram or road corridors suitable for building busways.
There are numerous proposals for new busway sections, especially
in the US and Australia. In Europe there are few sections of busways,
mostly constrained by unavailability of suitable space.
Technical aspects
In terms of the corridor widths needed, light
rail requires least space and busways most. Bus lanes and guided
busways are in between. In terms of passenger capacity, normally
light rail can transport more passengers than standard buses.
However, the example of Ottawa shows that the same number of passengers
can be transported as with light rail. Particularly interesting
is the new generation of guided buses, for example the TVR which
has about the same passenger capacity as a light rail vehicle.
Speed is mainly influenced not by the inherent
running space in free flow conditions, but also by stop density,
and existing light rail corridors usually have many more stops
than busways. As a result, buses running on busways are the fastest,
followed by light rail where it has right of way. Where light
rail shares space with car traffic, it tends to run faster than
buses in similar conditions.
Noise and pollution considerations favour light
rail, but innovations in the diesel technology will provide zero
emission buses. Noise is a problem with older vehicles, whether
rail or bus.
Running comfort for passengers is best with
light rail but can also be good with buses.
Overall, with regard to the technical aspects,
modern light rail vehicles operating on their own corridor will
rank slightly higher than buses in terms of space, speed, capacity,
comfort, pollution and noise although buses could do equally well
in terms of capacity and speed, and modern buses also on pollution.
Costs
Infrastructure cost per kilometre varies substantially
for all modes, depending on conditions and terrain. The most costly
is, of course, light rail operating in tunnels, and the cheapest
by far are bus lanes on existing road networks. In similar conditions,
the infrastructure costs for light rail, busways and guided buses
are closer together than has often been assumed. Light rail and
busways are very similar in cost. Guided busways are generally
slightly cheaper: We do have some examples where guided busways
are very much cheaper, but it would be overoptimistic to assume
this will always apply.
There are clear differences between the vehicle
costs, light rail being by far the most expensive, but also having
the longest life expectancy. However, the newly manufactured guided
buses, the TVR, Translohr show similar costs to a light rail vehicle.
Overall vehicle costs for buses are much cheaper than light rail.
For operating costs, some available examples
for Germany and the US indicate light rail as slightly cheaper
than buses, on a lifetime basis for similar levels of service.
However the examples from Pittsburgh and Ottawa show that the
operating costs per passenger km are about four pence cheaper
for buses than for light rail, even if the average loading factor
for Pittsburgh is included. This implies that the loading factor
is decisive and that light rail could only be cheaper than buses
if it is running at or near full capacity. The difference in the
cost per passenger km between the two New World cities reveals
that apart from the loading factor the difference in the labour
cost of bus drivers can be crucial.
—complementary measures
A number of complementary measures are easier
to implement with light rail than with buses, for instance pedestrianisation,
but complementary measures are vitally important to all public
transport modes and may hold the key to the success of the public
transport system as a whole. Conversely, investing in new and
expensive public transport systems without planning at the same
time to implement strong complementary measures will certainly
reduce the value of the investment and may even lead to a waste
of money.
—passenger gains and the level of transfer
between car users and public transport
Newly constructed public transport infrastructure
does in most cases generate significant growth in the number of
passengers—experience varies from a few per cent up to 50
per cent or more. There appears to be a tendency that European
cities which operate significant light rail networks have gained
more public transport passengers over the 10 year period 1986-96
than cities which rely only on buses. The reasons are not clear.
It may well be that those cities which operate light rail have
a tendency to implement more effective car restraining measures,
partly because light rail can help to provide the political consensus
to adopt more radical approach to car restraint than bus-based
systems have allowed. Effective complementary measures also influence
the growth in the number of passengers. However a few US cities
experienced a decline in the number of light rail passengers between
1990-95.
Yet the fact remains that in the majority of
cases most of the growth in public transport use has resulted
from a greater use by existing passengers, rather than making
substantial inroads into car use. Research suggests that for light
rail, transfer figures of more than 20 per cent are very much
the exception and not the norm. Transfer from car use to guided
buses, buses on busways or buses on bus lanes appear to be lower,
except for Dublin where the percentage was 16 per cent. We do,
however, have far less research on bus-related improvements. Dublin
is exceptional but it shows what can be achieved if traffic conditions
for car users are very bad. No information on transfer from car
to buses on busways was found.
It is clear that the level of transfer depends,
other things being equal, on the existing level of public transport
use. A world city like Paris which has a relatively high modal
split in favour of public transport can gain fewer additional
car users than a city with a very low initial public transport
share. The effect of rigorous hard complementary measures (such
as road pricing or private and public parking charges) is decisive,
whether the mode is light rail, guided bus, or buses operating
on busways, though the actual figures for transfer will—in
all cases—depend on the actual service, speed and fares
offered. Bus lanes normally have the disadvantage that they do
not give a clear right of way if car traffic is congested but
the Dublin example shows that strict enforcement of bus lanes
can have an astonishingly impressive effect. There has been significant
discussion, on the Continent and in the US, about the "rail
factor", suggesting that under equal conditions people will
prefer rail to bus. This was also shown in our own survey in four
British cities where we asked about 1,850 car drivers. About half
(47 per cent) of the car drivers preferred light rail and 36 per
cent guided bus, the rest not knowing. The problem for analysis
is that conditions are usually not equal: the rail factor has
not been researched adequately, thus a final conclusion is not
possible.
Each mode can be used for different purposes
Guided busways can be effective in overcoming
bottlenecks when the road network is congested but this could
be achieved more cheaply with strictly enforced bus lanes. In
all cases guided busways and busways seem not to be suitable for
city centres as they are too obtrusive and the feasibility for
integration into a denser built up urban environment is difficult
or impossible. In the best case these busways will become bus
lanes. If that is the case then the question may arise why not
use bus lanes for all those roads where priority is suggested.
A guided bus network can be an innovative public
transport system, to testing whether it works well in a medium
sized free standing city like Northampton may have international
significance. However, some politicians are reluctant to go for
a system which has not already been tested elsewhere, and it may
be that trials now planned in French cities will give British
local authorities more confidence.
Overall policy evaluation
The general policy evaluation which emerges
from this research is that the decisive influence on the success
of a policy of expanding public transport is not the specific
mode favoured, but the political commitment to an overall strategy
of reducing the dominance of car use in urban areas. Any of the
main public transport modes, whether it is bus, guided bus or
light rail, can secure expanding demand—if a high density,
high quality service is provided, and if complementary measures
(parking charges, large scale pedestrianisation, land-use policies
etc) are vigorously implemented.
In some cases, successful expansion of public
transport has been preceded by detailed cost benefit studies,
though this is not always the case. Sometimes this technical tool
is hardly used at all, and even where it is used there is often
a feeling of caution because of concerns that the figures are
unreliable or prone to manipulation, or because the underlying
decisions are much more influenced by other processes. In any
case the results of such studies are typically subordinated to
political considerations.
From this point of view, we can reconsider the
relative advantages of the different public transport modes.
Light Rail. Its main advantages turn
out to be what are often considered to be disadvantages—its
high cost and inflexibility. In political terms, these attributes
give it a high profile as a symbol of commitment in the early
stages, and a confident, futuristic symbol of the city when it
is implemented. "Inflexibility" becomes redefined as
"security"—the population is confident that a
change of political power or financial situation will not result
in the new system being taken away from them, and can therefore
plan their lives knowing that the system will be there in the
future. Political and professional careers can and have been built
around building a new light rail system. It has many friends—commercial,
civic, political, environmental—and few enemies.
Bus Priority. By the same argument, the
main disadvantages of relying on conventional buses are what are
usually assumed to be advantages—its cheapness and flexibility.
This always gives the temptation to be too cautious in implementation,
so that the service improvements—while overwhelmingly positive
in terms of value for money—are simply too small to make
a great impact. In effect, it requires much bolder political will
to make a success of (cheap) bus priority networks than (expensive)
light rail systems but if that will is there, then the balance
of advantage is profound.
Busways and existing guided buses emerge as
useful additions to the instruments available for public transport,
but probably limited to a specific fringe role—making use,
on occasion, of disused rail lines (but not justifying replacing
a still-functioning rail system), and for use in some outer areas.
The main disadvantage of busways is their required width which
is hardly available in European urban areas. They are unlikely
to be implemented in town centres in any country. They both have
some of the symbolic and career-enhancing qualities of light rail
systems, though on a smaller scale. We do not consider that busways
will be the central element of the public transport strategy of
any European town—though they could be useful additions
if the main strategy is right. The main disadvantage of the existing
technology of guided busways, in current UK conditions, is that
they may stimulate unrealistic ideas about massive systems which
will never happen, thereby diverting attention from the core strategic
questions. New types of guided buses, such as the TVR or Translohr
may have some future, especially in middle-sized towns where they
would operate like trams and not like buses and therefore would
have some of the characteristics of light rail. However, significantly
more practical experience and research are needed before a final
judgement on the new generation of guided buses could be made.
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