Emulating an Integrated Activity Based Land Use – Transportation Model to Provide a More Effective Spatial Decision Support Tool

Effective strategic regional planning requires both a capability for forecasting the future state of the system under business as usual conditions, and an ability to test the effect of possible infrastructure developments and policy interventions on the system. We use a comprehensive simulation platform designed to support strategic spatial planning by modelling the long-term spatial dynamics of land use, population, and economic activity. It is being used to evaluate planning and policy options for containing urban sprawl and enhancing environmental quality. Most applications have been to Flanders, Belgium, where it is known as the RuimteModel. Here we describe an extension designed to improve simulations of future land use/cover and activity patterns, and to give additional indicators useful to spatial planners and policy makers in mobility. The extension, the Mobility Module, deals with changes in travel times, modal split, and flow volumes driven by changes in the location of population, employment, and other activities as calculated in the core model. Since the Mobility Module is integrated with the original RuimteModel, it also provides feedback from changed travel times, modal split, and flows to show their impact on the location of the various activities and the associated land use/land cover patterns, as well as their impact on environmental quality. Although the Mobility Module deals with modal split, traffic volume, and travel speed on network links, it is not a full transportation model. Rather it emulates in a computationally efficient way the results of such a model. Early results show that incorporating the Mobility Module in the RuimteModel results in significant changes in land use and activity patterns. In particular, residential development tends to be more dispersed. This result has clear implications for the efficacy of several anti-sprawl policies being considered by the Flemish government, and consequently for the attainment of spatial-environmental goals.