Natural hazards and flood events are part of nature. They have always existed and will continue to exist. In the most cases, floods are caused by climatological phenomena, which are out of human control.
Due to the present change in the Earth’s climate the precipitation pattern will also change. In general, this means a greater probability of hazardous flooding and unexpected risk.
Although floods are natural phenomena, human activities and human interventions into the processes of nature, such as alterations in the drainage patterns from urbanisation, agricultural
practices and deforestation, development of land on the floodplain area, have considerably changed the situation in entire river basins.
At the same time, exposure to risk and vulnerability in flood-prone areas has been growing constantly.
The flood risk increases as a consequence of the climate change and human interventions into the processes of nature, leading to an increase in the probability of the occurrence of flood events and to the intensified use of floodplains for settlements and the rising accumulation of valuable goods. (ICPDR Flood action program)