Floods And Floodings In The Sebou Watershed (Morocco) Between 1980-81/2013-14: Statistical And Mapping Approach

Abstract

The ultimate aim of the study is to examine the hydrological variability of flow causing floods, as well as its distribution in the Sebou watershed. It is also aimed at assessing the risks of flooding in the lower valley of the Sebou and its tributaries. In March 2010, flood caused significant financial and human damage. Eventually, it was necessary to determine the return periods of the extreme flows, and the importance of the floods in the watershed. Therefore, the study is based on the statistical approach to examine the instantaneous maximum flows. The results yielded that there is  an increase in extreme flows in the stations studied, which gives rise to numerous floods in the Sebou watershed. In this regard, we have modelled the floods; then we selected the biggest flood -March 10^th, 2010- in the Gharb plain using geographic information systems (ARC-GIS 10.2 and HEC-RAS 5.0.7). Therefore, the flooded area in the Gharb varies depending on the water ratio, the intensity of the flow and the topography of the plain.