Assessment of Water Erosion Risk Based on Satellite Imagery and GIS Mapping: Case of the Bouregreg Basin

Abstract

Water erosion is a major problem in Morocco, and its vulnerability is growing all the time. Indeed, the Bouregreg watershed is one of several Moroccan basins affected by this phenomenon, resulting in annual soil losses that disrupt the natural balance of the basin's ecosystems and hamper the region's socioeconomic development. This soil loss is particularly marked at the Sidi Mohamed Ben Abdellah dam, located near the mouth of the Bouregreg river, and leads to silting estimated at several million dirhams per year, with significant financial consequences. The aim of this study is to investigate water erosion and map erosion risks in the Bouregreg watershed, using remote sensing and a geographic information system (GIS). An exhaustive study of the study area was carried out with the aim of characterizing the main factors involved in the evolution of water erosion in the Bouregreg basin. The results of this study showed that the simultaneous presence of watercourses running through easily erodible areas, as well as steep slopes with no plant cover, aggravate this phenomenon and exert a control over its evolution.