ABSTRACT
Flash flood or "sail", is a typical flow of mud through dry valleys which are located in an arid and semi-arid area. It is the outcome of torrential rain which occurs suddenly during the end of the wet season and covers the dry valley of Assi river. It causes catastrophic consequences on the environment and the economy of some villages in the North Beqaa. It is essential to make a comprehensive study on the dry valley of Fakehe village which includes an analysis of the geo-morphological, hydrological, and climatic factors
Remote Sensing and Geographic Information System [GIS] are considered as an effective and advanced technological tool to study the hydrological characteristics of Fakehe valley such as the nature of hydrological network, drainage index, soil permeability, and slope gradient. Then combining together all these factors using a [GIS] model one can identify the weak spots which cause or intensify the flash floods
After identifying the sensitive areas in Fakehe area many appropriate solutions are proposed to reduce the effects of the "sail" such as terraces and reforestation of steep slopes. Another solution is to widen and deepen the U form of the flash flood bed in order to contain the big muddy waves. Finally, the installation of many pipes is another solution to protect farmlands