Various flooding present one of the most severe natural disasters in Slovenia and all over the world. Floods can cause a huge material damage and are a threat to many human lives. In recent years we have witnessed increasing trends in flooding. Most of them are the result of climate variability, which is reflected also in discharge and flow regimes changes. Humans can also be the guilty part of it, with reckless building and urbanization in flooding areas. Flooding is a natural phenomenon, which represent a danger and risk only if it’s close to the population. Monitoring and alerting before the flooding have a significant impact, as with it we can prepare people for the worst and minimize the threat and damage. In order to achieve alerting as precise as possible and timely, the floods have to be accurately analyzed and the connections between rainfall, discharge and runoff in the watershed have to be determined. This was also the main aim of this master thesis. We analyzed larger flood events and extreme flows of the Savinja River basin.
Because of dense populations of the flood area the watershed of the Savinja River is one of the most problematic watersheds in Slovenia. Prevailing torrent character of the Savinjaa River and its tributaries increasing the flooding issues in this area. Heavy rainfall can cause incredibly fast increase in flow. The overflow can be very shortly after the rainfall practically all over the watershed. The most problematic places are towns of Celje and Laško, and some smaller towns and villages in the upper part of the watershed, where smaller torrents come to an expression. Analysis showed that flooding is caused mainly by heavy rainfall. Great influence has also antecedent soil moisture, which greatly decreases the ability of retention of the rainfall in the watershed and with it increases the runoff. The duration of the flood waves is short. The peak discharge is usually achieved in the timeframe of a day or even earlier. Analysis of the monthly extremes showed that flood events can be expected mostly in months of November and September.