In the XXI century around 200 notable dam and reservoir failures happened worldwide causing massive fatalities and economic costs. In order to reduce the losses, managers usually identify flooding area due to dam break using standalone hydrodynamic models and then import the results within a GIS to perform risk analysis. This two step procedure is time expensive, error prone, due to export/import requirements, and not user friendly. For this reason with this work, a new numerical model for the solution of the two-dimensional dam break problem has been implemented in the GRASS GIS as a GIS embedded module. The model solves the conservative form of the 2D Shallow Water Equations (SWE) using a Finite Volume Method (FVM); the inter-cell flux is computed by one-side upwind conservative scheme extended to a two-dimensional problem. The new developed GIS module, among others outputs, allows to derive maximum intensity maps that can be directly used for risk assessment.
Hypothetical dam break flood simulation using the implemented GRASS GIS embedded module