低平水田地帯の雨水流出解析

Abstract

In the previous paper, what criterion should be adopted in simplification of complicateddrainage channel networks was discussed fundamentally in order to apply the numericaltechnique of unsteady flow to simulate hydrographs of flood runoff in low-lying drainagebasin. As the result, it was disclosed that the channel networks could be simplified to thesecond order channel system.This paper deals with an actual example of flood runoff in the Ogura research basincomposed of hills, urban districts and mainly paddy fields. Flood runoff from non-inundatedwatersheds such as hills and urban districts is estimated by applying the kinematic wavemethod, and flood flow in low-lying basin is simulated by solving the unsteady flow equationnumerically after simplification of channel networks based on the criterion disclosed in theprevious paper.The results of runoff analysis show good coincidence with observed hydrographs, andverify the usefulness of the criterion for simplifying the complicated channel networks.