Flood Risk Assessment from Dam Failure based on 2007/60/EC European Flood Directive: A case study on Kelefinas Dam in Greece

European Flood Directive (EFD) 2007/60/EC of the European Parliament and of the Council on the assessment of flood risks was ratified in Greece under Ministerial Decision (MD) 31822/1542/E103. According to this MD, flood means the temporary covering by water of land not normally covered by water. Apart from the natural causes, e.g. floods from rivers, ephemeral water course and average sea level raising, the EFD includes floods from dams or other hydraulic works failures which can cause immense damage and loss of life when they occur. During EFD public consultation, several local stakeholders can participate and express their opinion about the effects of EFD implementation.

In this study we assess the flood risk from a hypothetical failure of the Kelefinas dam, in Southern Greece. The assessment is based on the requirements of the EFD 2007/60EC which are different than what is currently implemented till now. We develop an index based hierarchy method to assess the impact of flood risk on human health, environment, cultural heritage and economic activities. The Special Secretariat for Water used the index based hierarchy method across all the water bodies of Greece by taking into account important factors of floods such as depth distribution, flow velocity, etc. In addition, the potential flood area of Kelefina theoretical dam failure is discretized into grid of cells, which is used for flood risk calibration and verification.

The calibrated flood risk, along with the public consultation comments and remarks were used to establish objective criteria at a national level in order to help Civil Protection Agency and other Competent Authorities for the Dams Safety Emergency Plans drafting and implementation.