We now recognise that the provision of new transport capacity on the supply side does not simply better accommodate demand. It can generate additional demand (indeed it has also been shown that when transport supply is reduced so too does demand reduce – traffic can ‘disappear’). Predicting the demand for new travel and providing for it can amount to a self-fulfilling prophecy, i.e. the predicted demand arises through the very act of providing the capacity. This underlines that while it may be politically sensitive to suggest ‘social engineering’, we have a tremendous opportunity to shape the future rather than reactively respond to it in terms of transport.
Data from different parts of the world has revealed a change in the correlation between economic activity (measured by Gross Domestic Product) and transport activity (measured by road traffic). Against a previous trend of ‘traffic intensity’ of economic activity increasing (i.e. more traffic needed per unit of economic output), in more recent years this has reversed: the traffic intensity of the economy is reducing. While this is not fully understood, it may relate to the changing makeup of the economies of the countries concerned (decline in manufacturing and growth in services), urban agglomeration effects and the growth in digital connectivity following the advent of the internet and world wide web; growth in domestic aviation may also be a factor. This suggests that it may be possible increasingly to realise economic prosperity through effective land use planning and urban development alongside investment digital infrastructure and services as an alternative to or complement to the role of the transport system.
Change can sometimes be dramatic. The closure of European air space in 2010 as a result of a volcanic ash cloud from Iceland is an example; the 2011 earthquake and tsunami in Japan, is another. However, change is often much more of a process than an event and one that is gradual yet powerfully cumulative over the passage of time. The world wide web is 25 years old this year. A growing proportion of the world’s population has been absorbing the succession of developments in ICTs over its lifetime to date into their lifestyles and behaviours. When we look back over time we can observe how such change can become transformative. The move into the motor age was, over a period of decades, transformative for society and for transport. Further transformation is all but inevitable.
Given such lessons from the past, we need to consider developments in transport that are aligned to shaping the type of future society that is desired (by current and also for future generations). It is important to give more attention to anticipating the indirect and longer-term effects of policy and investment decisions, recognising that effects can take some time to emerge as individuals and organisations adapt their behaviours to evolving conditions. Fundamentally, we should not be addressing the future of transport but the future of access. In turn we should focus strongly on the importance of what might be termed a triple-access system of transport, physical proximity and digital connectivity. We do not know what future society will want to do or be able to (afford to) do in relation to access though we do know people can adapt. We should therefore focus upon developing a balanced triple-access system and, accordingly, a balance of investment and policy support across this system that may transcend the traditional remits of government departments.