Due to population growth and densification, and expanding construction, disaster risk in the world and its specific parts of the world is steadily increasing. Earthquakes cause the most damage, followed by floods. Floods are characterized by the highest frequency of events. In this research, annual data on 25 hydrological gauging stations of the considered territory were used to study the characteristics of maximum discharges and maximum levels of rivers in the Yesil water management basin. Data on maximum water levels and discharges are generalized because they are most important in the study of floods and the organization of flood control. It is the maximum level that determines the area and depth of flooding of territories. This study assessed the provided values of maximum levels and maximum water discharges by several methods (method of moments, the graph-analytical method for the full distribution, truncated distribution). For assessing flood damage, a map of the distribution of the maximum floodplain inundation depth over the basin area was constructed, taking into account the flood hazard classification by floodplain inundation layer. Quantitative assessment of hydrological extremes characterizing the danger of flooding has been carried out for gauging stations of Yesil water management basin during this research.