The software Faitou (= makes all) has been devloped by the Institute of Hydraulic Construction of the Swiss Federal Institute of Technology at Lausanne by Jérôme Dubois (actually HydroCosmos) and Professor Michel Pirotton of the Service of Applied Hydrodynamics and Hydraulic Construction of the University of Liège. It is a quasi 3D, non-stationary and geographically distributed model for simulating precipitation and runoff of a watershed. It is based on a new law that allows modelling of all types of flow. The input data can be spatially distributed time series and the computation grid is automatically generated. Watercourses are also automatically detected by analysing the topographical data. The model is thus able to couple runoff to flow in water courses.