Probabilistic delineation of flood-prone areas based on a digital elevation model and the extent of historical flooding: the case of Ouagadougou

R. De Risi; F. Jalayer; F. De Paola; M. Giugni

doi:10.21701/bolgeomin.125.3.005

Authors

R. De Risi Department of Structures for Engineering and Architecture, University of Naples Federico II
F. Jalayer Department of Structures for Engineering and Architecture, University of Naples Federico II. (2) Department of Civil, Architectural and Environmental Engineering, University of Naples Federico
F. De Paola Department of Civil, Architectural and Environmental Engineering, University of Naples Federico II
M. Giugni Department of Civil, Architectural and Environmental Engineering, University of Naples Federico II

DOI:

https://doi.org/10.21701/bolgeomin.125.3.005

Keywords:

flood-prone areas, Topographic Wetness Index, Bayesian parameter estimation, GIS, Africa

Abstract

The delineation of flood-prone areas is one of the most important steps for flood risk assessment and mitigation. This study uses a probabilistic and DEM-based framework for the delineation of flood-prone areas based on information about the extent of historical flooding in the area of interest. This is particularly useful for the delineation of flood-prone areas in cases where more accurate hydraulic profile calculations are not available. The delineation of flood-prone areas is carried out by using the Topographic Wetness Index (TWI) which allows for the delineation of a portion of a hydrographic basin potentially exposed to flooding by identifying all the areas characterized by a topographic index that exceeds a given threshold. A Bayesian updating framework is used for estimating the TWI threshold for identifying the flood-prone areas based on available information on the spatial extent of historical flooding. An application of the proposed method is demonstrated for the delineation of potentially flood-prone areas in the city of Ouagadougou, based on the observed spatial extent of the 2009 flooding event in the city.

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References

Apel, H., Aronica, G. T., Kreibich, H. & Thieken, A. H. 2009. Flood risk analyses-how detailed do we need to be? Natural Hazards, 49, 79-98. https://doi.org/10.1007/s11069-008-9277-8

Degiorgis M., Gnecco G., Gorni S., Roth G., Sanguineti M., and Taramasso A.C., 2012, Classifiers for the detection of flood-prone areas using remote sensed elevation data. Journal of Hydrology, 470-471, 302-315. https://doi.org/10.1016/j.jhydrol.2012.09.006

De Risi, R. & Jalayer, F. 2013. Identification of hot spots vulnerability of adobe houses, sewer systems and road networks. Available: http://www.cluva.eu/deliverables/CLUVA_D2.1.pdf.

De Risi, R., Jalayer, F., DePaola, F., Iervolino, I., Giugni, M., Topa, M. E., Mbuya, E., Kyessi, A., Manfredi, G., Gasparini, P., 2013. Flood Risk Assessment for Informal Settlements, Natural Hazards, 69 (1), 1003-1032. https://doi.org/10.1007/s11069-013-0749-0

Gall, M., Boruff, B. J. & Cutter, S. L. 2007. Assessing flood hazard zones in the absence of digital floodplain maps, comparison of alternative approaches. Natural Hazards Review, 8, 1-12. https://doi.org/10.1061/(ASCE)1527-6988(2007)8:1(1)

Jalayer, F., De Risi, R., De Paola, F., Giugni, M., Manfredi, G., Gasparini, P., Topa, M. E., Nebyou, Y., Yeshitela, K., Nebebe, A., Cavan, G., Lindley, S., Printz, A. & Renner, F. 2013. Probabilistic GIS-based method for delineation of urban flooding risk hotspots. Natural Hazards - in press. https://doi.org/10.1007/s11069-014-1119-2

Jaynes, E. T. 2003. Probability theory: The logic of science, Cambridge University Press. https://doi.org/10.1017/CBO9780511790423

Kirkby, M. J., 1975. Hydrograph modelling strategies. In, PEEL, R. F., CHISHOLM, M. D. & HAGGETT, A. P. (eds.) Progress in physical and human geography. London.

Manfreda, S., Di Leo, M. & Sole, A. 2011. Detection of Flood-Prone Areas Using Digital Elevation Models. Journal of Hydrologic Engineering, 16, 781-790. https://doi.org/10.1061/(ASCE)HE.1943-5584.0000367

Manfreda, S., Sole, A. & Fiorentino, M. 2007. Valutazione del pericolo di allagamento sul territorio nazionale mediante un approccio di tipo geomorfologico. 4, 43-54.

Manfreda, S., Sole, A. & Fiorentino, M. 2008. Can the basin morphology alone provide an insight into flood-plain delineation? WIT Trans. Ecol. Environ, 118, 47-56. https://doi.org/10.2495/FRIAR080051

Qin, C.-Z., Zhu, A. X., Pei, T., Li, B.-L., Scholten, T., Behrens, T. & Zhou, C.-H. 2011. An approach to computing topographic wetness index based on maximum downslope gradient. Precision Agriculture, 12, 32-43. https://doi.org/10.1007/s11119-009-9152-y