Backward analysis of the Bílá Desná dam break outflow

In September 1916, the Austro-Hungarian Empire (today the Czech Republic) experienced the failure of the embankment dam Bílá Desná (historically named Weiße Desse), which at that time was the most disastrous dam failure in central Europe. In this study, available information on the failure of the Bílá Desná dam was gathered and analysed. The initiating cause of the Bílá Desná dam failure was an internal erosion. For the backward analysis of the dam failure, the method of analogy, empirical formulae, and three numerical models, AREBA, DL Breach and HEC-RAS were used. Due to uncertainty in the reservoir volume, the solution was carried out for the originally determined (during the dam design) and newly determined reservoir volumes. The analysis indicates the peak breach outflow range between about 360 and 810 m3/s. The most realistic and probable peak outflow discharge is about 520 m3/s. The comparison of individual methods indicate that the AREBA numerical model using Opendata (2024) provides the most realistic failure hydrograph.