Author(s): Laszlo Koncsos; Edina Balogh
Linked Author(s):
Keywords: Inundation simulation; 2D hydrodynamical model; Flood damage estimation
Abstract: Our aim was to develop the methodology for an optimal flood management strategy for the Tisza valley in Hungary, a country with rather unfavourable natural-geographical conditions from the point of view of flood risks. To achieve this, a fast computation methodology was developed and the consequences of two types of catastrophe were analysed: those due to dyke breaching and those due to geotechnical reasons. To establish the magnitude of damages caused by possible catastrophe events we simulated inundation processes. This was done assuming the breakdown of dykes at 30 relevant catastrophe points and with the help of a 2D model, which is based on the solution of the hydrodynamical equations originating from the Navier-Stokes equations of the shallow water wave. To estimates losses we developed population, industrial and agricultural loss functions. The individual elements of this model were connected in a Monte Carlo simulation for a hundred years. As a result of the inundation simulation the time series of inundation depths at the individual catastrophe points became available. Based on this, and using spatial information and statistical databases, the magnitude of losses at the individual catastrophe points were estimated with the help of the loss computation methodology developed by us. As the result of the simulation examination projected for a hundred years we produced the loss probability density functions and risks for the individual scenarios. On the basis of the results we established that, in the scenario of a climate change that we assumed, the expected annual risk would grow more than twofold. A similar growth can be seen if the assumed effects of the floodplain saturation in hundred years is taken into account.
Year: 2007