Application of the maxima distribution to the evaluation of the variability of flood risks in the Odra River basin on the basis of quarterly maxima of daily water levels

The method of assessing the flood risk variability has been presented based on maximum value distributions. Hydrological data were used in the form of daily water levels for the period 1981–2013. The collected data originate from the Malczyce Hydrological Station on the 300th km of the Odra River. To assess the risk of flooding based on the collected data quarterly highs were selected. As a measure of flood risk, the authors suggested the probability of exceeding the emergency level in the studied section of the river. This risk was calculated using the theoretical distribution function of the quarterly heights of the water level. The study used the Gumbel distribution. A special attention was paid to the possibility of using the presented solutions for an integrated flood risk management process in accordance with applicable national and European legislation.