Theoretische minimale pendelafstand als ruimtelijke karakteristiek: een denkoefening

In many policy documents on mobility and transport much hope is set on "good spatial planning" as an effective means to improve the efficiency and sustainability of mobility. However, while the spatial structure is generally recognized as a prerequisite for trip generation, observed travel behaviour and particularly trip distances are additionally induced by such "external" factors as the general prosperity, the level of congestion, the quality of roads or the price of fuel. From the point of view of land use planning, it is essential to estimate what portion of the actual traffic is caused by the spatial structure itself, and what portion represents in fact an extrapolation originating from the above mentioned external factors. In the pursuit of sustainable development, we examine the role of the spatial structure in a quantitative way on the basis of "excess commuting", a concept that initially emerged from Hamilton's (1982) seminal work. A case study in the north of Belgium shows us that large variations in minimum commuting distances occur, which define to a large extent opportunities for shrinking commute distances again in the future, e.g. by external factors such as rising fuel prices, extreme congestion or dissuasive policies.