Sustainability is tough, both in terms of how to define it and
in terms of bringing it about in reality. Rather than becoming
entangled in complicated definitions of the concept, it is better
to set out a broad-based definition relevant to the transport
domain, to explore how we can use substantially less rather
than more carbon-based energy sources to provide the mobility
needed for society to function efficiently. This means that
transport must accept its responsibility to take at least a “fair”
share of any targets set at the national (or international) level.
In the past, transport has been the one major sector of the
economy for which it has been difficult to make cuts in energy
use and in carbon emissions.
This paper takes a historical perspective on how cities have
become less sustainable in terms of transport, but it will argue
that many positive changes have taken place even before the
current concerns over CO2
and oil. There seem to be many
more opportunities for further change through the encouragement
of high-quality city-based lifestyles that do not require
high levels of carbon-based mobility. But it is in the newly
emerging “megacities” that the main problems occur, as there
is a discontinuity between the slow growing, stable, and wellstructured
cities of the west and the rapidly growing, unstable,
and unstructured cities of the east.
The debates need to address the role of transport and
land-use planning in these megacities that are growing at rates
and on a scale that do not reside comfortably in the traditional
planning framework. New visionaries are required to confront
the problems of megacities, and innovative planning processes
are necessary to facilitate rapid and adaptive change so that
new urban structures can accommodate growth yet maintain
flexibility. A hundred years of knowledge and experience about
different forms of transport and urban structure needs to be
concentrated into the next 10 years so that these megacities
can emerge as the new models for transport and urban sustainability