Journal cover Journal topic
Natural Hazards and Earth System Sciences An interactive open-access journal of the European Geosciences Union
Nat. Hazards Earth Syst. Sci., 18, 1493-1516, 2018
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.
Research article
30 May 2018
Low cost, multiscale and multi-sensor application for flooded area mapping
Daniele Giordan1, Davide Notti1, Alfredo Villa2, Francesco Zucca3, Fabiana Calò4, Antonio Pepe4, Furio Dutto5, Paolo Pari6, Marco Baldo1, and Paolo Allasia1 1National Research Council of Italy, Research Institute for Geo-Hydrological Protection (CNR-IRPI), Strada delle Cacce 73, 10135 Turin, Italy
2ALTEC S.p.A., 10146 Turin, Italy
3Department of Earth and Environmental Science, University of Pavia, Via Ferrata 1, 27100 Pavia, Italy
4National Research Council of Italy, Institute for the Electromagnetic Sensing of the Environment (CNR-IREA), Via Diocleziano 328, 80124 Naples, Italy
5Civil Protection Service of Turin Metropolitan area, 10095 Grugliasco, Italy
6Digisky S.r.l., 10146 Turin, Italy
Abstract. Flood mapping and estimation of the maximum water depth are essential elements for the first damage evaluation, civil protection intervention planning and detection of areas where remediation is needed.

In this work, we present and discuss a methodology for mapping and quantifying flood severity over floodplains. The proposed methodology considers a multiscale and multi-sensor approach using free or low-cost data and sensors. We applied this method to the November 2016 Piedmont (northwestern Italy) flood. We first mapped the flooded areas at the basin scale using free satellite data from low- to medium-high-resolution from both the SAR (Sentinel-1, COSMO-Skymed) and multispectral sensors (MODIS, Sentinel-2). Using very- and ultra-high-resolution images from the low-cost aerial platform and remotely piloted aerial system, we refined the flooded zone and detected the most damaged sector. The presented method considers both urbanised and non-urbanised areas. Nadiral images have several limitations, in particular in urbanised areas, where the use of terrestrial images solved this limitation. Very- and ultra-high-resolution images were processed with structure from motion (SfM) for the realisation of 3-D models. These data, combined with an available digital terrain model, allowed us to obtain maps of the flooded area, maximum high water area and damaged infrastructures.

Citation: Giordan, D., Notti, D., Villa, A., Zucca, F., Calò, F., Pepe, A., Dutto, F., Pari, P., Baldo, M., and Allasia, P.: Low cost, multiscale and multi-sensor application for flooded area mapping, Nat. Hazards Earth Syst. Sci., 18, 1493-1516,, 2018.
Publications Copernicus
Short summary
We present a multiscale and multi-sensor methodology for flood mapping using free or low-cost data. We first mapped flooded areas at basin scale using free satellite data using both SAR and multispectral sensors. At local scale we refine mapping using very high-resolution images from Remotely Piloted Aerial System and terrestrial car camera, then we used these data to create 3-D model with structure from motion (SfM). All these data allowed creating accurate flooded area and water depth maps.
We present a multiscale and multi-sensor methodology for flood mapping using free or low-cost...