Wikipedia
Kalypso (software)
Kalypso is an open source modelling program. It focuses on numerical simulations in water management and ecology such as the generation of inundation and flood risk maps by hydrologic and hydrodynamic models and GIS functionality.
The Kalypso software system has been collaboratively developed in a joint project by the company Björnsen Consulting Engineers (BCE) and the department for river and coastal engineering at Hamburg University of Technology, Germany. It is available for download at SourceForge.net under the GNU LGPL.