In recent years, dramatic river flooding has occurred in several regions of Europe causing numerous casualties and the damage reached unprecedented proportions.
There are two basic reasons for this: a) the increased frequency of extreme weather events, likely due to modifications of the climate regime, b) built-up areas (e.g. urbanisation and infrastructures) continue to grow mainly in flood prone areas. The combination of these two elements is particularly worrying since changes in land use associated with urban development affect flooding in many ways. Urbanisation generally increases the size and frequency of floods and may expose communities to increasing flood hazards (Konrad 2003). Altogether, these trends contribute to an unsustainable development pattern, with an increasing exposure to natural hazards in large regions of Europe .
The protection of human and capital assets from natural hazards is high in the agenda of the European policies and is directly addressed in the European Regional Development Fund for the programming period 2007-2013. The prevention of risks is indeed a priority for investments in the actions linked to the three major objectives for structural funds interventions (namely: convergence, competitiveness and cooperation).
This technical note describes a contribution to the evaluation of exposures to flood risk in 13 out of the 15 Countries that can receive support from Structural Funds under the Convergence objective. The work is part of a wider frame of research activities carried out at the Weather Driven Natural Hazard action of the Institute for Environment and Sustainability of JRC.
The first step towards the definition of a strategy for the prevention of natural disaster is the evaluation of the risk (Barredo 2004). Three components determine the “risk”, according to the definition proposed by Kron (2002): hazard, vulnerability and exposure. Based on this definition, the risk may be decreased by reducing the size of any one or more of the three contributing variables - the hazard, the elements exposed and/or their vulnerability. The reduction of any one of the three factors to zero would consequently eliminate the risk.