Manisa Kizildere flood currents modeling with HEC-RAS

In this study, inundated areas are determined when 100, 500, and 1000 years of repetitive floods are observed in Kızıldere Tributary, Gediz River, which passes through the boundaries of Manisa city. Since there is no current observation station at Kızıldere to use in assessing flooded ares, the flood events of the repeated years are found using the Mockus method. Rainfall data observed in Muradiye and Üçpınar stations are used to represent Kızıldere Tributary Basin. Statistical analyzes of precipitation data are performed to determine the most appropriate probability distribution. The most suitable probability distribution for rainfall data is found to be Log-Pearson Type-3 through statistical tests. Using this distribution, annual maximum precipitation heights of 2, 5, 10, 25, 50, 100, 500 repetitive years to be used in Mockus method are calculated. The flood events of 2, 5, 10, 25, 50, 100, 500 and 1000 years belonging to Kızıldere Tribautary are found by unit hydrograph obtained from Mockus method for the basin. For 100, 500 and 1000-year floods with HEC-RAS model, inundated areas in Kızıldere Basin have been determined.