One cannot avoid flood and drought but hydrological extremes can be managed in a sustainable manner. The responsible institutions have developed two main approaches so far: the prevention actions and the (post-) crisis management. The prevention approach includes hydraulic works for flood defense and reservoirs to store water both for flood and drought control, and also meteorological and hydrological modeling to forecast the possible hazard evolution and to issue information and recommendations for the exposed population. The crisis management approach relies on emergency plan development and post crisis management. That requires a deep implication of governing institutions in adequate policy development and in a good coordination between services. The final objective is to limit the consequences of flood and drought hazard for the exposed population and for the economy, but also to recover and to establish a normal situation as soon as possible after a crisis. Flood and drought hazards are different, both in their duration and in their intensity. Therefore, their management strategies are different. Statistical regional analyses are important tools for modeling the frequency distributions of flood and drought events in terms of intensity and duration, which are the two components of the hazard severity. They are used to design hydraulic works and refer to a mean recurrence period of time.

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