Contribution of GIS and Simulations of Capacity of Hydraulic Structures to the Mapping of Flood Zones in the City of Agadir in Central Morocco

IJEP 44(5): 445-453 : Vol. 44 Issue. 5 (May 2024)

Abdellaali Tairi1*, Ahmed Elmouden1, Lhoussaine Bouchaou1,2 and Abderrahmane Wanaim3

1. Ibn Zohr University, Laboratory of Applied Geology and Geo-Environment, Faculty of Sciences, Agadir 80000, Morocco
2. Université Mohammed VI Polytechnique (UM6P), Morocco; International Water Research Institute (IWRI), Ben Guerir 43150, Morocco
3. Ibn Zohr University, Department of Earth Sciences, Faculty of Applied Sciences, Agadir, Morocco


The hydraulic infrastructures of the city of Agadir are in poor condition and require major rehabilitation. They have been affected by floods and rainfall that have flooded most of the urban facilities of the city of Agadir. The present study aims at simulating and evaluating the capacity of two hydraulic works (Lahouar and Tassila) to face floods. These works are in the floodable black points of the city of Agadir. This study was carried out using modeling tools, empirical formulas and functions integrated into software dedicated to geographic information systems (GIS) and by exploiting climatic, hydrological, topographic, digital terrain model, geological data, etc. The simulated project flows were estimated using the rational method. The hydraulic capacity of two structures was simulated using the Culvert Master software. The simulation results for two hydraulic structures, Lahouar and Tassila, show that Tassila structure is powerless against the project flow (Q10) with a return time of 10 years, while Lahouar withstands the flow (Q10 and Q20) at 10 and 20 years return time and shows no flow (Q100) for the 100 years return time. These results can be used not only for flood risk prevention but also for the management of urban sewerage systems.


Simulation, Floods, Lahouar, Tassila, GIS, DEM, Flow, Return time


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