It is commonly asserted that so-called compact development is the urban form most able to
sustainably accommodate growth by reducing travel distances and conserving land, but credible
supportive evidence remains limited.
This study rigorously and realistically tested the relative performance of spatial options over the
next 30 years for three distinct kinds of English city regions. Statistical models first forecast the
behavior of people within interacting markets for land and transport. These outputs were then
fed to established simulation models to generate 26 indicators measuring the economic
efficiency, resource use, social and environmental impact of the spatial options. This permitted
an explicit comparison of the costs and benefits of compact against sprawling urban forms for
these regions.
While the prototypes - i.e. Compaction, Market led development (sprawl), Planned expansion
(edge expansion and/or new towns) - were indeed found to differ in their sustainability, no one
form was clearly superior. Rather the change to ‘white collar’ lifestyles and associated
population growth dominates the impacts on the natural environment and resources, far
overwhelming those attributable to spatial urban form.