Extreme events such as floods can endanger human lives and cause large economic damage. The Savinja River catchment is one of the most frequently flooded areas in Slovenia, Europe. In order to evaluate the impact of the proposed flood mitigation measures on the flood safety in this catchment, the combined hydrological and hydraulic modelling approach was carried out. The hydrological model Hydrologiska Byråns Vattenbalansavdelning (HBV-light) was used to perform hydrological modelling. The hydraulic calculations were carried out using the HEC-RAS 5.0.3 model in order to simulate the combined one- and two-dimensional unsteady flow. Using the calibrated and validated hydrological and hydraulic models, the impact of the proposed measures was assessed in the light of the sustainable flood management. Additionally, with analyses of the historical data and past flood events, we were able to investigate the characteristics of the extreme floods in this area and also downstream at the confluence with the Sava River. Moreover, it was found that the backwater effect has an important role on the water level and flood safety along the river reach, which is often neglected in the aspect of flood management.
Part of the book: Achievements and Challenges of Integrated River Basin Management