Estimating Optimal Design Frequency and Future Hydrological Risk in Local River Basins According to RCP Scenarios

In South Korea, flood damage mainly occurs around rivers; thus, it is necessary to determine the optimal design frequency for river basins prevent damage. However, there are not enough studies showing effect of climate change on hydrologic frequency. Therefore, estimate according future scenarios, this study examined urban flooding area and extreme rainfall that can in future. After estimating frequency, hydrological risks 413 local were evaluated Representative Concentration Pathway (RCP) scenarios 4.5 8.5 after regenerating daily rainfalls from HadGEM2-ES model into hourly using Poisson cluster. For RCP 4.5, increased relative established by 3.13% average. 8.5, 2.80% The 4.58% P2(2040–2069) period 4.39% P1 (2021–2039) 8.5. These results suggest will likely decrease, safety also decrease.