NUMERICAL SIMULATIONS OF FLOOD AND INUNDATION FOR EVALUATING THE EFFECTS OF NOKOSHI AND OPEN LEVEE IN JOBARU RIVER

Abstract

A traditional flood control technology, such as nokoshi and open levee is existing in Jobaru river in Saga Plain. In this research, a quantitative evaluation of these facilities' effect is performed by 1-D and 2-D numerical simulations. The 1-D simulation shows characteristics of nokoshi and open levee and also gives a boundary condition for the 2-D simulation. The 2-D simulation gives how the flood flow is treated in the retarding basin. The flow behavior is compared with the geotechnical investigation results in which sediments are sampled to estimate how the sediments were carried and settled down during the inundation.