Flood Susceptibility Assessment through Statistical Models and HEC-RAS Analysis for Sustainable Management in Essaouira Province, Morocco
Abdellah Khouz,
Jorge Trindade,
Pedro Pinto Santos,
Sérgio C. Oliveira,
Fatima El Bchari,
Blaid Bougadir,
Ricardo A. C. Garcia,
Eusébio Reis,
Mourad Jadoud,
Tarik Saouabe,
Said Rachidi
Affiliations
Abdellah Khouz
Centre for Geographical Studies, Institute of Geography and Spatial Planning, University of Lisbon, 1600-276 Lisbon, Portugal
Jorge Trindade
Centre for Geographical Studies, Institute of Geography and Spatial Planning, University of Lisbon, 1600-276 Lisbon, Portugal
Pedro Pinto Santos
Centre for Geographical Studies, Institute of Geography and Spatial Planning, University of Lisbon, 1600-276 Lisbon, Portugal
Sérgio C. Oliveira
Centre for Geographical Studies, Institute of Geography and Spatial Planning, University of Lisbon, 1600-276 Lisbon, Portugal
Fatima El Bchari
Department of Earth Sciences, Polydisciplinary Faculty of Safi, Cadi Ayyad University, Marrakech 40000, Morocco
Blaid Bougadir
Laboratory of Applied Sciences for the Environment and Sustainable Development (SAEDD), Higher School of Technology Essaouira, Cadi Ayyad University, Marrakech 40000, Morocco
Ricardo A. C. Garcia
Centre for Geographical Studies, Institute of Geography and Spatial Planning, University of Lisbon, 1600-276 Lisbon, Portugal
Eusébio Reis
Centre for Geographical Studies, Institute of Geography and Spatial Planning, University of Lisbon, 1600-276 Lisbon, Portugal
Mourad Jadoud
Department of Earth Sciences, Faculty of Sciences El Jadida, Geosciences and Environmental Techniques Laboratory, Chouaïb Doukkali University, El Jadida 24000, Morocco
Tarik Saouabe
Georessources, Geoenvironment and Civil Engineering Laboratory, Faculty of Sciences and Techniques, Cadi Ayyad University, Marrakech 40000, Morocco
Said Rachidi
Systems Analysis, Information Processing and Industrial Management Laboratory (LASTIMI), High School of Technology Salé, Mohammadia School of Engineers (EMI), Mohamed V University, Rabat 8007, Morocco
Floods are natural disasters that often impact communities living in low-lying areas in the northern and central parts of Morocco. In this study, our aim was to create a flood susceptibility map using three methods; the hierarchy process (AHP) frequency ratio model (FR) and the weights of evidence (WoE) model. We extensively examined the area identified by these approaches using a hydraulic analysis software called HEC-RAS (version 6.3.1). Our analysis focused on the Essaouira watersheds in Morocco, where we identified around 197 flood locations. Out of these, we randomly selected 70% for modeling purposes while the remaining 30% were used for validation. Ten factors that influence floods were considered, such as slope, elevation, proximity to rivers, drainage density, stream order, land use patterns, rainfall data, lithology (permeability level) index (TWI), and curvature. We obtained these factors from data sources. Finally, we generated a flood susceptibility map and evaluated its accuracy by calculating the area under the curve (AUC). The validation results confirmed that all three models were robust and effective with an AUC of 90. Moreover, the research uncovered a trend of vulnerability with the most susceptible area being in close proximity to the city of Essaouira along the Oued Ksob. A detailed analysis using HEC-RAS was conducted at this identified location, pinpointing the village of Diabat as highly exposed. These findings hold significance for flood management, empowering decision makers, scholars, and urban planners to make informed choices and implement strategies that can minimize the impact of floods in susceptible regions while minimizing potential damages.
