The assessment of hydraulic engineering structures based on soil material is incomplete due to vadose and often transient seepage processes that have a significant effect and requires a methodical upgrade. At the same time, extreme meteorological events are amplifying the uncertainties associated with these processes that arise from long periods of draughts or heavy rainfall. A joint research project to develope a prediction system for dam and levee failures deals with these effects. Their influence on geohydraulics and soil mechanics is analyzed using experimental and mathematical models. This article presents the combination and expansion of a FEM-software for holistic geohydraulics with an independent, Open-Source stability module.