Cultural Heritage in the Light of Flood Hazard: The Case of the "Ancient" Olympia, Greece

Floods are natural hazards with negative environmental and socioeconomic impacts at a local and regional level. In addition to human lives, facilities, and infrastructure, flooding is a potential threat to archaeological sites, with all the implications for the cultural heritage of each country. Technological developments of recent years, particularly concerning geospatial technologies (GIS, Remote Sensing, etc.), have brought novel advantages to hydrological modelling. This study uses geoinformatics to quantify flood hazard assessment. The study area is the ungauged torrent of Kladeos River, located in Peloponnese, Greece. Geomorphological analysis combined with hydrological modelling were performed in a GIS-based environment in order to study the hydrological behavior of the Kladeos River basin. The hydrological analysis was carried out with rainfall data and hypothetical storms using a 5 x 5 m digital terrain model. The quantitative features of the catchment were calculated in order to determine its susceptibility to flooding. The hydro-morphometric analysis revealed stream order anomalies in the drainage network which, combined with the morphology of its upper and lower parts, enhance the possibility of flood events. The primary results indicated that there is an increased possibility of extensive flooding in the archaeological site, depending on the severity of the rainfall, since the basic geomorphological characteristics favor it. The proposed methodology calculates parameters such as flow rate, flow velocity, etc., in order to measure and quantify flood hazard and risks in the area of interest.