Basement V4—A Multipurpose Modelling Environment for Simulation of Flood Hazards and River Morphodynamics Across Scales

The numerical modelling of hydro- and morphodynamics in watercourses is of great importance for both the advancement of scientific understanding of underlying processes and for design in engineering practice. For this purpose, and focusing on alpine and subalpine conditions, the modelling software BASEMENT has been developed in the last two decades. The simulation environment is currently composed by different tools, either freeware or open-source. BASEMENT version 4 consists of two main modules, namely BASEMD (MD—Multi Domain) and BASEHPC (HPC—High Performance Computing). The software provides a unified simulation workflow and graphical user interface for setting up numerical models with both modules. BASEMD offers multiple options to couple 1D and 2D domains, whilst BASEHPC supports both the use of multi-core processors and general-purpose graphics processing units (GPGPUs) to increase calculation efficiency. This can speed up simulations many times over, depending on the problem at hand. In both modules, the hydrodynamics is calculated based on the shallow water equations whilst morphodynamics accounts for both bed- and suspended load transport. In the present contribution some application possibilities of the software will be illustrated by means of four examples: (i) flood peak discharge capping using automatic control, (ii) lateral flood diversion with different model coupling options, (iii) progressive dam breaching due to overtopping and (iv) tsunami wave propagation. The steadily growing number of users confirms that BASEMENT is a useful tool for the efficient investigation of complex and extensive questions in river and hydraulic engineering.