The identiﬁcation of ﬂood-prone areas is a critical issue becoming everyday more pressing for our society. A preliminary delineation can be carried out by DEM-based procedures that rely on basin geomorphologic features. In the present paper, we investigated the dominant topographic controls for the ﬂood exposure using techniques of pattern classiﬁcation through linear binary classiﬁers based on DEM-derived morphologic features. Our ﬁndings may help the deﬁnition of new strategies for the delineation of ﬂood – prone areas with DEM-based procedures. With this aim, local features—which are generally used to describe the hydrological characteristics of a basin—and composite morphological indices are taken into account in order to identify the most signiﬁcant one. Analyses are carried out on two different datasets: one based on ﬂood simulations obtained with a 1D hydraulic model, and the second one obtained with a 2D hydraulic model. The analyses highlight the potential of each morphological descriptor for the identiﬁcation of the extent of ﬂood-prone areas and, in particular, the ability of one geomorphologic index to represent ﬂood-inundated areas at different scales of application.
How to cite: Manfreda, S., C. Samela, A. Gioia, G. Consoli, V. Iacobellis, L. Giuzio, A. Cantisani, A. Sole, Flood-Prone Areas Assessment Using Linear Binary Classifiers based on flood maps obtained from 1D and 2D hydraulic models, Natural Hazards, 79 (2), 735-754, (doi: 10.1007/s11069-015-1869-5), 2015. [pdf]
Three different geomorphic approaches to the identiﬁcation of ﬂood prone areas are investigated by means of a comparative analysis of the input parameters, the performances and the range of applicability. The selected algorithms are: the method proposed by Manfreda et al. (2011) based on a modiﬁed version of the Topographic Index (TIm); the linear binary classiﬁer proposed by Degiorgis et al. (2012), which uses different geomorphic features related to the location of the site under exam with respect to the nearest hazard source; the hydro-geomorphic method by Nardi et al. (2006) simulating inundation ﬂow depths along the river valley with the associated extent of surrounding inundated areas. Comparison has been carried out on two sub-catchments of the Tiber River in Central Italy. The simulated ﬂooded areas, obtained using the selected three methods, are evaluated using as a reference the Tiber River Basin Authority standard ﬂood maps. The aim of the research is to deepen our understanding on the potential of geomorphic algorithms and to deﬁne new strategies for prompt hydraulic risk mapping and preliminary ﬂood hazard graduation. This is of foremost importance when detailed hydrologic and hydraulic studies are not available, e.g., over large regions and for ungauged basins.
How to cite: Salvatore Manfreda, Fernando Nardi, Caterina Samela, Salvatore Grimaldi, Angela Celeste Taramasso, Giorgio Roth, Aurelia Sole, Investigation on the use of geomorphic approaches for the delineation of ﬂood prone areas, Journal of Hydrology, Pages 863 – 876 (doi: 10.1016/j.jhydrol.2014.06.009),2014. [pdf]