[ Simulation de la propagation des crues dans la plaine d’inondation de la vallée du fleuve Sénégal ]
Volume 40, Issue 3, September 2023, Pages 1032–1043
Yaya Dieme1, Mamadou Bop2, and Vieux Boukhaly Traore3
1 Laboratoire d’Hydraulique et de mécanique des fluides, FST, Université Cheikh Anta Diop de Dakar B.P. 5005 Dakar-Fann, Senegal
2 École Supérieure Polytechnique, Université Cheikh Anta Diop de Dakar, corniche Ouest BP 5085 Dakar-Fann, Senegal
3 Laboratoire d’Hydraulique et de mécanique des fluides, FST, Université Cheikh Anta Diop de Dakar B.P. 5005 Dakar-Fann, Senegal
Original language: French
Copyright © 2023 ISSR Journals. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
To simulate the propagation of floods in the Senegal River valley in order to lay out the flood risk maps, we used hydraulic methods calculating the flooded surface from the topography of the minor and major beds. To this end, the HECRAS model and GIS (ARCGIS and HEC-GeoRAS) were used on the Bakel-Matam reach. The work was done in steady state and allowed us to map the risk of flooding on this Bakel-Matam section in the Senegal River valley for different floods. to do this work, water levels and flows were used for the calibration and validation of the HEC-RAS model. The Nash criterion was used to optimize the HEC-RAS parameters. The flood extent obtained by this model was exported and visualized in ArcGIS. Thus, the flood mapping results obtained made it possible to detect a certain number of villages at risk of flooding for the hundred-year flow, wich shows that the Senegal River Valley is vulnerable to floods. Moreover, this was demonstrated by the average catastrophic flood which caused flooding that could impact approximately 24,071 people. The characteristics (height, speed and propagation time) for each flood were analyzed. The promising results obtained showed that the couple HECRAS and GIS is an effective tool for mapping floods and could be used as a tool to help planners in planning.
Author Keywords: Simulation, flood, flooding, Senegal River.
Volume 40, Issue 3, September 2023, Pages 1032–1043
Yaya Dieme1, Mamadou Bop2, and Vieux Boukhaly Traore3
1 Laboratoire d’Hydraulique et de mécanique des fluides, FST, Université Cheikh Anta Diop de Dakar B.P. 5005 Dakar-Fann, Senegal
2 École Supérieure Polytechnique, Université Cheikh Anta Diop de Dakar, corniche Ouest BP 5085 Dakar-Fann, Senegal
3 Laboratoire d’Hydraulique et de mécanique des fluides, FST, Université Cheikh Anta Diop de Dakar B.P. 5005 Dakar-Fann, Senegal
Original language: French
Copyright © 2023 ISSR Journals. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Abstract
To simulate the propagation of floods in the Senegal River valley in order to lay out the flood risk maps, we used hydraulic methods calculating the flooded surface from the topography of the minor and major beds. To this end, the HECRAS model and GIS (ARCGIS and HEC-GeoRAS) were used on the Bakel-Matam reach. The work was done in steady state and allowed us to map the risk of flooding on this Bakel-Matam section in the Senegal River valley for different floods. to do this work, water levels and flows were used for the calibration and validation of the HEC-RAS model. The Nash criterion was used to optimize the HEC-RAS parameters. The flood extent obtained by this model was exported and visualized in ArcGIS. Thus, the flood mapping results obtained made it possible to detect a certain number of villages at risk of flooding for the hundred-year flow, wich shows that the Senegal River Valley is vulnerable to floods. Moreover, this was demonstrated by the average catastrophic flood which caused flooding that could impact approximately 24,071 people. The characteristics (height, speed and propagation time) for each flood were analyzed. The promising results obtained showed that the couple HECRAS and GIS is an effective tool for mapping floods and could be used as a tool to help planners in planning.
Author Keywords: Simulation, flood, flooding, Senegal River.
Abstract: (french)
Pour simuler la propagation des crues dans la vallée du fleuve Sénégal afin de disposer les cartes à risque d’inondation, nous avons utilisé les méthodes hydrauliques calculant la surface inondée à partir de la topographie des lits mineur et majeur. A cet effet le modèle HECRAS et les SIG (ARCGIS et HEC-GeoRAS) ont été utilisés sur le bief Bakel-Matam. Le travail a été fait en régime permanent et nous a permis de cartographier le risque d’inondation sur ce tronçon Bakel-Matam dans la vallée du fleuve Sénégal pour différentes crues. Les hauteurs d’eau et les débits ainsi que le critère de Nash ont permis le calibrage du modèle HEC-RAS dont les résultats ont été exportés et visualisés dans ArcGIS. Ainsi les résultats de cartographie des crues obtenus ont permis de détecter un certain nombre de villages à risque d’inondation pour le débit centennal montrant ainsi que la vallée est vulnérable face aux crues. D’ailleurs cela a été démontré par la crue catastrophique moyenne qui a engendré des inondations pouvant impactant environ 24071 personnes. Les caractéristiques (hauteur, vitesse et temps de propagation) pour chaque crue ont été analysées. Les résultats prometteurs obtenus ont montré que le couple HECRAS et SIG est outil efficace de cartographie des crues et pourrait être utilisé comme outil d’aide aux aménagistes dans la planification.
Author Keywords: Simulation, crue, inondation, fleuve Sénégal.
How to Cite this Article
Yaya Dieme, Mamadou Bop, and Vieux Boukhaly Traore, “Simulation of the propagation of floods in the flood plain of the Senegal River valley,” International Journal of Innovation and Applied Studies, vol. 40, no. 3, pp. 1032–1043, September 2023.
