Application of two-dimensional hydraulic modelling in flood risk mapping. A case of the urban area of Zaio, Morocco

Abstract

Flood risk mapping is important to prevent damage from flooding in urban areas. In this study, a flood risk map was produced with hydrological and hydraulic data. The methodology implemented in this article was based on both the mathematical calculation of the maximum flow rate and the software Iber 2.4.3 is used as a 2D hydraulic modelling tool verified using field observation data. The flood conditioning factors used in the modelling were precipitation, slope, depth, land use. Other factors, including urban density, socio-economic conditions and the responses of 500 questionnaires distributed to people in the study area, Zaio NORT EAST Morocco, were taken into account to analyze the vulnerability to flooding. A flood risk map was then produced using flood risk and vulnerability maps. The mapping method presented as a precautionary measure against flooding not only alerts the public to flood risk issues and reduces it more effectively in identified vulnerable areas, but also helps the authorities to make decisions about flooding strategies, land use and urban development.