Assessment of the Impact of Climate Change on Design Flood Flows in Small Earth Dams and Adaptation Measures

Abstract

Due to the impacts of climate change, heavy rainfall disasters are expected to become more severe and frequent. In small earth dams, one of the agricultural water facilities, it is necessary to consider the impacts of increased rainfall due to climate change. Therefore, in this study, the impacts of climate change on the design flood flows of reservoirs were evaluated using 5-km spatial resolution future projection data after showing the evaluation method, and the effects of adaptation measures on the evaluation results were discussed. The results showed that the future change ratio of the reservoir design flood flows due to climate change is 1.06 to 1.30 times for the 2℃ rise scenario and 1.10 to 1.85 times for the 4℃ rise scenario. The results also showed that the provision of available capacity before rainfall as an adaptation measure to climate change is effective for the 2℃ rise scenario, but must be combined with the widening of spillways for the 4℃ rise scenario.