Physically based river basin modelling within a GIS: the LISFLOOD model

Although many geographical information systems (GISs) are very advanced in data processing and display, current GIS are not capable of physically base d modelling. Especially, simulating transport of water and pollutants throu gh landscapes is a problem in a GIS environment. A number of specific routi ng methods are needed in a GIS for hydrologic modelling, amongst these are the numerical solutions of the Saint-Venant equations, such as the kinemati c wave approximation for transport of surface water in a landscape. The PCR aster Spatial Modelling language is a GIS capable of dynamic modelling. It has been extended recently with a kinematic wave approximation simulation t ool to allow for physically based water flow modelling. The LISFLOOD model is an example of a physically based model written using the PCRaster GIS en vironment. The LISFLOOD model simulates river discharge in a drainage basin as a function of spatial data on topography, soils and land cover. Althoug h hydrological modelling capabilities have largely increased, there is stil l a need for development of other routing methods, such a diffusion wave. C opyright (C) 2000 John Wiley & Sons, Ltd.