Integrated planning of water and land-use

The role of water in spatial planning has received increasing attention in recent years. It was, for example, one of the leading motives in the preparation of the latest National Spatial Planning Note for The Netherlands. For the preparation of such spatial plans, and to support the associated policy analysis, there is a need to fully identify and characterize the interactions between the water sector and spatial planning and establish the process for making consistent joint projections for the water sector and land-use. This should account for spatial claims from the water sector, balance those claims with claims from other sectors, and feed back spatial constraints and opportunities. Land-use markets and government policies (translated e.g. in spatial reservations) form an important input in this balance. Modeling is indispensable to keep track of spatial characteristics and trace changes. Most of the available modeling considers a layered structure with a layer for national/regional projections and a GIS based layer to keep track of land use changes. Basically such model makes a distribution (rule based) of the national projections into the GIS based spatial raster, followed by an impact assessment based on the changes in the raster. Those models are generally weak in representing the processes driving land use changes such as the housing and labor market and – the water sector. The challenge remains to set up a suitable module covering these spatial - and water sector development processes. Based on the experience of the authors with many water studies and the recent development of a space-transport modeling tool (integration of transport and land-use), a sketch will be made of the requirements for such module. The scope for such planning tool will be illustrated (with data for The Netherlands), addressing key aspects such as competition for space, costs, risk, and environmental impact.