INSPECTION FOR FLOOD MITIGATION EFFECT OF SMART PADDY FIELD DAM IN YONEBUKURO BASIN

Abstract

 In this study, an analytical model of the Yonebukuro drainage pumping station basin in Osaki City, Miyagi Pref, was constructed to evaluate the flood mitigation effects of Smart Paddy Field Dam, and inundation simulations were conducted with the conventional and smart paddy field dams under multiple rainfall scenarios. The results suggest that the smart paddy field dam is more effective in mitigating flooding than the conventional paddy field dam, since the smart paddy field dam does not over-flow the rice paddy even if all rainfall is stored when rainfall does not exceed the drainage standard water level of the smart paddy field dam. However, in the case of rainfall that exceeds the drainage base level, the flood mitigation effect is reduced when a conventional paddy field dam is compared with a smart one that always cuts the peak drainage outflow. This is because the outflow is the same as that in rice paddies without the paddy field dam when the rainfall exceeds the base level. In addition, it was shown that the loss of storage pockets when the rainfall peak shifts backwards leads to weakening of the flood mitigation effect.