Assessing land use /cover variation effects on flood intensity via hydraulic simulations: A case study of Oued El Abid watershed (Morocco)

Abstract

Despite the semi-arid to arid nature of its climate, Morocco is exposed, like all the Mediterranean countries to inundations, which can be very damaging for public and private infrastructure, and cause many victims. On Monday 10 August 2015, one of Oued El Abid tributary raised in a remarkable way, causing five deaths and serious material damage in Iminwargue village (Azilal province). This study comes to assess the impact of land use/cover variation in the multiplication of floods frequency via the hydraulic simulations. For this purpose, relying on land use/cover variation from 1987 to 2017, flow and precipitation database, we made a hydraulic simulation of the 2015 event and the 100 years recurrence inundation. As results, the land use/cover decrease is always followed by an increase in flows peak even that all recorded precipitations are more or less similar. The case study hundred years inundation prediction shows a 5.03 m increase in the river and all population near banks, agricultural land and other useful infrastructure such as roads and bridges are invaded. These results show that more catastrophic events could be reproduced and oblige the decision makers in Oued El Abid watershed to be aware of the critical situation.

Keywords

• Land use/cover
• inundation
• Oued El Abid watershed
• hydraulic simulation
• hydrological response