  Modelling river physical processes is of critical importance for flood
protection, river management and restoration of riverine environments.
Developments in algorithms and computational power have led to a wider spread
of river simulation tools. However, the use of two-dimensional models can still
be hindered by complexity in the setup and the high computational costs. Here
we present the freeware BASEMENT version 3, a flexible tool for two-dimensional
river simulations that bundles solvers for hydrodynamic, morphodynamic and
scalar advection-diffusion processes. BASEMENT leverages different
computational platforms (multi-core CPUs and graphics processing units GPUs) to
enable the simulation of large domains and long-term river processes. The
adoption of a fully costless worflow and a light GUI facilitate its broad
utilization. We test its robustness and efficiency in a selection of
benchmarks. Results confirm that BASEMENT could be an efficient and versatile
tool for research, engineering practice and education in river modelling.
