Flash floods are generally caused by heavy or excessive rainfall in a short period of time, about less than 6 hours. They are usually characterized by raging torrents after heavy rains that rip through river beds, urban streets, or mountain canyons sweeping everything before them. They can occur within minutes or a few hours of excessive rainfall. They can also occur even if no rain has fallen, for instance after a levee or dam has failed, or after a sudden release of water by a debris.
In Northern Ethiopia, in recent times, the severity of the flash floods has increased, and there is a necessity for active modeling to comprehend the magnitude of the problems and alleviate their disastrous effects.
For successful applications of flash floods modeling in water resources development and management practices in the semi-arid regions of Ethiopia, this research will focus on the following specific objectives: