Disasters related to mountain torrents in the High Atlas region: their behavior in space and time based on geomorphological, sedimentological, and stratigraphic analyses; case study of the hydraulic basin of Wadi Lahouar, Agadir, Morocco

Abstract

The studied region is part of the watershed of Oued Lahouar, located in the western region of Agadir, Morocco. Oued Lahouar runs through the center of the city, creating potential flood risks. Agadir is generally characterized by a semi-arid climate and rare precipitation. The soils in this area are fragile, primarily due to the lack of rain, the intensification of flash floods, and water erosion. The city's location, as a foothill-mountain area crossed by significant watercourses, plays a crucial role in exacerbating floods. These floods occur in years of heavy precipitation and high flow rates, causing significant damage to the population and property. Therefore, our objective is to study the Oued Lahouar watercourse, which traverses the city, to identify areas most susceptible to flash floods, drought, and water erosion. In this context, an analysis of sediments in the hydrological network of the Oued Lahouar watershed will be conducted, accompanied by risk mapping using remote sensing data and geographic information systems (GIS). These efforts aim to standardize methods for estimating flood periods and soil degradation rates. The ultimate goal is to propose development measures based on research findings to mitigate the risks facing the study area.