عنوان مقاله [English]
Undoubtedly, floods are known as one of the most important natural disasters. In practice, the flood is considered to be the most enormous disaster in terms of mortality and financial losses.
In a ten-year period in the world (1988-1988), about 390000 people were killed by natural disasters, 58% of which were flood casualties, 26% related to earthquakes, and 16% were caused by storms and other disasters.
The related financial losses in this short period were about $ 700 billion, 33% of which caused by flood, 29% by earthquake and 28% were related to the storm. Throughout history, humans have been attracted to the fertile lands that are located on the course of previous floods, and have made their lives easier by settling close to rich sources of water and food in these lands. The same river or water flow that provides people with livelihood will make them more vulnerable to flooding.
Flood can be caused by heavy rainfall, accumulation of heavy and abnormal sediment behind dams or dams’ failure, rapid melting of snow, blockage of the course of rivers due to landslides, or explosions of water reservoirs.