Relative merits of bus- and rail-based
17. While it was agreed that investment in LRT could
bring many benefits, opinions differed as to which mode offered
most advantages and was most cost-effective. Light rail was favoured
by most who submitted evidence as it "very nearly offers
the best of both buses and trains".
LRT is able to move large numbers of people quickly and efficiently
along the busiest corridors. Services are reliable and punctual
because they are not subject to disruption from other road traffic
as most systems operate over their own rights of way and are given
priority at junctions. Modern systems are easily accessible for
passengers with impaired mobility, and the quality of the vehicles,
stops and passenger information is better than that offered by
most bus services. They also benefit from relatively simple, high
frequency service patterns.
18. The perceived weaknesses of fixed track modes,
and light rail in particular, namely their relatively high cost
and inflexibility compared to buses, can in fact prove to be advantages:
the former ensures that the project has a high profile in its
early stages and commitment from policy-makers, while the latter
gives a sense of permanence. Thus potential passengers can confidently
incorporate the new mode into their future journey plans. Conversely,
cheapness and flexibility, traditionally thought of as the main
strengths of buses, may in fact prove to be disadvantages. It
has been argued that those characteristics mean that although
service improvements can be made at low cost, the fact that they
can be introduced incrementally, and taken away very quickly,
undermine confidence in them, and so prevent them making a significant
The perceived advantages of light rail in particular make it popular
with car users
and, as a result, it has a proven ability to achieve modal shift.
19. Some of the disadvantages of the bus can be overcome
through the adoption of features usually associated with light
rail, such as improved vehicles and stops. Such developments will
help to reduce the current 'quality gap' between the two modes,
improving perceptions of buses. However, more substantial problems
remain, such as the fact that on-street trams tend to be given
a greater degree of on-street priority, improving their reliability
and average speed by comparison to buses. Thus the relative attractiveness
of buses and light rail is determined both by real and perceived
factors: London Transport told us that it believed that there
is little firm evidence that buses could have a similar impact
on car use as rail-based public transport, but agreed that further
research will be required to establish whether this is a consequence
of real differences in performance between the modes or more to
do with their images.
20. FirstGroup accepted the general view that light
rail is the most appropriate mode for moving large volumes of
passengers between a small number of origins and destinations,
but said that guided buses offer the "vast majority"
of advantages of fixed track systems at a lower cost. It conceded
that guided buses are less attractive to motorists who perceived
them as less of a 'step change' from conventional buses than light
rail, but argued that this could be largely overcome through the
use of state-of-the-art buses, with interiors of a standard that
match those of light rail vehicles. More important is the greater
flexibility of a guided bus system, since once outside the guided
section the bus can travel in any direction required, reducing
the need to change between vehicles or modes. As a result passengers
benefit from reduced end-to-end journey times.
21. The guided bus system has a further advantage
over light rail. As well as being used over relatively long distances,
such as the 'O-Bahn' in Adelaide, Australia, significant benefits
can be gained from modest expenditure on short sections of guideway,
which can be built to enable buses to by-pass traffic congestion.
By contrast the infrastructure for a light rail route is required
along the full length of the corridor. In Leeds the introduction
of the guideway has reduced peak journey times to their off-peak
levels and has made bus services more reliable, making the bus
competitive with the car. At the suburban end of the corridor,
services fan out to serve estates which would be too small to
justify light rail extensions.
FirstGroup doubted whether a light rail system would have been
capable of increasing public transport patronage along the corridor
by much more than its guided bus services.
22. Despite their apparent benefits, guided busways
have been introduced in relatively few places, so opportunities
for drawing comparisons with light rail are limited. In certain
circumstances, however, guided bus systems have been chosen in
preference to light rail. The transport authorities in Adelaide,
Australia, have since 1986 developed an extensive network of services
which make use of the 'O-Bahn', a 12 kilometre-long track running
from the edge of the city centre to the north eastern suburbs.
After joining the guideway at the edge of the city centre, buses
run at high speed calling at a few intermediate stops before leaving
the guideway and spreading out into the suburbs. We were told
that guided bus services are particularly suited to Adelaide,
which is surrounded by sprawling suburbs of low population density
which could not be served economically by light rail services.
The 'O-Bahn' is thought to have been successful in attracting
former motorists, despite the city's high level of car dependence.
23. Greater cost effectiveness is often cited as
the main advantage of bus-based LRT over its rail-based counterparts.
While the cost of building a guideway varies considerably depending
on the type of construction, if it is installed along an existing
bus corridor it might be as low as £1 million per lane kilometre,
excluding the cost of other infrastructure such as vehicles, depots
and so on. By contrast, the capital cost of a new light rail line
is between £3 million and £10 million per kilometre,
although this range includes the cost of associated infrastructure,
vehicles and diverting utilities.
However, the capital cost of an entirely new guided bus system
with segregated track, new stations and new vehicles might be
comparable with that of light rail, although in Adelaide, Australia,
we were told that the 'O-Bahn' had cost only two-thirds of the
estimated cost of a light rail line over the same route.
Moreover, the operating costs of a light rail system over its
thirty-year life are much lower than those of a bus-based alternative.
24. The Confederation of Passenger Transport believed
that it was important to note that light rail was considerably
cheaper than new metro or heavy rail construction, and as such
should be regarded as "a cheap railway rather than an expensive
The capital cost of light rail was also thought to compare favourably
with that of building an urban road of comparable capacity.
In addition, the Light Rail Transit Association warned that bus-based
systems should not be seen as a cheap alternative to light rail,
since the Government might realise at a later date that only small
numbers of car users have switched to this form of public transport.
This view was echoed by the PTE Group, which said that it had
found that light rail was more cost effective than superficially
The benefit-to-cost ratio for the original Manchester Metrolink
system, for example, was substantially higher for light rail than
any of the other options considered.
Nevertheless, as we have said, the Government requires promoters
to justify the choice of light rail, rather than lower cost alternatives,
when submitting applications for funding.
25. The Minister felt that where light rail was clearly
the best way of meeting local transport demands it was right to
adopt that option. The decision to do so would, however, be based
on "as objective a set of criteria as possible",
in view of the high cost of light rail projects. Although the
two schemes were not directly comparable, the Minister observed
that "an awful lot of buses" could be bought for the
difference between the £24 million cost of the proposed 24-kilometre
Crawley Fastway scheme, which is based on buses, and the 21-kilometre
Midland Metro, which is a light rail project, at £145 million.
It was essential, therefore, that light rail proposals were examined
26. The Government did believe, however, that light
rail had an important role to play in providing integrated transport
in certain areas, and that this mode of transport would be "an
important component" of the forthcoming ten-year transport
strategy. Despite their high cost, the Government has supported
light rail schemes where they represent good value for money and
are an essential part of a local strategy. As stated earlier,
the Government believes that bus priority measures can also bring
significant benefits at much lower cost. It told us that it is
obviously important to adopt the most appropriate form of transport
for local circumstances, and advocated a "horses for courses"