Policy instruments (1) - Transport Policy and Planning in Great Britain - page 190

In some cases there are links between renewal and enhancement as variants of an
investment strategy. In Tyneside and Greater Manchester for example the 'like for like'
replacement of life-expired former electrified suburban rail lines was not considered
an economic proposition and the opportunity was taken to introduce new light rail
systems instead. On the national rail network the degree of disruption caused by
track and signalling renewal schemes means that these are normally combined with
planned enhancements wherever practicable. Disruption to traffic during highway
(re-)construction can also be an important factor in weighing up the relative merits of
improvements on or off the present road alignment.
As the general standard of transport networks is improved over a long period
of time, so the scale of investment involved in making a significant improvement
increases (whether this is by the remodelling of an existing facility or the building of a
new one). This has several important implications:
• Enhanced facilities will be fewer in number . (There are fewer motorways than
all-purpose main roads, fewer high speed rail lines than ordinary main lines.) The
gap in opportunities between places which do or don't benefit from enhanced
facilities widens and economic activity increasingly focuses on the corridors and
urban centres which have received major transport investment. (Access to major
airports is a further dimension of this spatial phenomenon.)
• The costs involved in achieving a 'step-change' improvement are very large ,
as are the potential risks and wider consequences (good and bad). Inevitably any
group of decision-makers will be very wary about committing themselves to such
a change when the lead-in and pay-back times are long and there are typically
few 'get out' opportunities along the way. (The plight of Eurotunnel shareholders
following the introduction of cheap short-haul flights and the resulting collapse in
forecast use of the Channel Tunnel provides a very salutary lesson.) On the other
hand prolonged procrastination can produce widespread uncertainty and blight
in related transport and development decisions.
• Greater attention deserves to be focused on optimising existing networks ,
both through managing their use and through carefully targeted, relatively small-
scale enhancements. As well as entailing fewer risks (including the potential for
significant political opposition) this is likely to represent the most cost-effective
use of available resources. This message underpinned both the Route Utilisation
Studies initiated by the SRA and the new 'charter' set for the Highways Agency
in Managing Our Roads (DfT 2003a). The same message was reaffirmed in the
context of longer term planning in the Eddington Report (24.5).
12.3 The rationale for public investment
The rationale for public investment in transport can be linked to the more general
arguments about the role of the State discussed in Chapter 9. There are two main strands.
The first relates to the general road network as a result of its special characteristic as
a 'public good'. The second relates to all transport modes and concerns the capturing
of benefits which are either not reflected in market transactions or whose market price
does not reflect their full social value.