The article concerns the application of selected distributions of extreme values to estimate the risk of occurring of flood danger in Lower Silesia. In the study a daily water level on the Nysa Klodzka River was used, that was gathered in the hydrological station in Bystrzyca Klodzka. From the collected data from the period 1981-2013 biannual maximum water level was selected. Two theoretical distributions: Gumbel and Frechet were fitted to the empirical distribution of biannual maximal. The best fitted two distributions were used for the exemplary assessment of flood danger.