Using geographic information systems (GIS) and remote sensing to map flood extent and to assess flood hazard in erythropotamos river basin (Evros, Greece)

Περίληψη

According to 2007/60/EC Directive of the European Parliament and the Council of the European Union, floods are recognised as a phenomenon that causes severe damage upon both the environment and mankind. Having this Directive in mind, the present study focuses on the flood of the river basin of the tributary river of Evros called Erythropotamos. Also, taking under consideration that the event occurredbetween the 9thand 18th of February in 2010 in this area, this preliminary study attempts to achieve detection and mapping of its extent, along with determining if there is a connection between the latter and the geologic formations of the study area. Moreover, data layers such as land cover, hydrogeology, topography and EU-DEMs 1 arc second (approximately 25m) spatial resolution elevation data, were used in order to achieve hazard assessment in Erythropotamos catchment with the aid of Hec-RAS software and its ArcGIS extension HEC-GeoRAS by compiling flood hazard and risk maps. Finally, these maps were evaluated by comparingthe flood extent depicted in them with the flood extent that was initially mapped with ENVISAT imagery by usingmeasures of fit tests. The results evaluated the existing methodologies for their effectivenessand accuracy to achieve flood risk assessment mapping and raise the question if there are ways in which these results can be improved.