Author(s): Atsuya Ikemoto; So Kazama; Takeo Yoshida; Hayata Yanagihara
Linked Author(s): So Kazama
Keywords: Inundation flood analysis: Irrigation reservoir: Damage cost: Climatic change
Abstract: Flood mitigation is expected to be achieved by storing rainwater and floodwaters on agricultural land and agricultural facilities and pre-discharging stored water from agricultural facilities. This study aimed to demonstrate the potential of reservoirs to reduce flood damage in areas where reservoirs have been used for irrigation for a long time and to evaluate the amount of damage caused by flood inundation by conducting flood inundation analysis considering reservoir storage capacity. The damage amount was evaluated. The relationship between the damage reduction rate and the reduction rate and the storage capacity of reservoirs was discussed and examined in more detail, especially for areas with high potential for flood control, such as Hyogo, Akita and Aomori prefectures. By using three Shared Socioeconomic Pathways (SSPs) (SSP1-2.6, SSP2-4.5, and SSP5-8.5), we evaluated the flood control potential of reservoirs under future climate. To determine the maximum effect, no water was assumed to be in the reservoir at the start of the calculation. The analysis results showed that the damage reduction rates ranged from 3.7% 5.1% in Aomori Prefecture, 1.7% 6.0% in Akita Prefecture, and 2.0% 10.1% in Hyogo Prefecture. In Akita Prefecture, the difference between the maximum and mean values was small, and the difference between the minimum and mean values was large. In Aomori Prefecture, the differences between the maximum and mean values and between the minimum and mean values are small for each future climate. Therefore, stable reservoir use for flood control is expected. Akita and Hyogo prefectures are expected to have high flood damage reduction effects by flood control depending on the SSPs-RCPs but may be strongly affected by uncertainties.
DOI: https://doi.org/10.3850/978-90-833476-1-5_iahr40wc-p1306-cd
Year: 2023