DYNAMIC RAINFALL-RUNOFF AND FLOOD-INUNDATION ANALYSIS OF AKATANI RIVER BASIN IN KYUSHU-HOKUBU HEAVY RAIN IN 2017

Abstract

 A new numerical model for two-dimensional rainfall-runoff and flood-inundation flow analysis was constructed and dynamic rainfall-runoff and flood-inundation analysis of Akatani river basin in Kyushu-hokubu heavy rain in 2017 was performed by the model. A new procedure for a dry/wet boundary over a topography is incorporated into the model based on FDS(Flux Difference Splitting) solver. The model was also verified against observed water level and maximum inundation area. It showed that the proposed model can reproduce it with reasonable accuracy. A rainfall-runoff and flood-inundation process and were also examined based on the numerical results.