Development of an Integrated Model for Inundation Flows in Coastal Urban Areas

Abstract

An integrated inundation model that consists of a 2D overland flow model, a rainfall-runoff model and a 1-D sewerage network flow model is developed. The overland flow model is refined to capture the effects of urban structures on flooded flows on Cartesian coordinate system using the concept of flow porosity and a CIP scheme. The integrated model is applied to the inundation due to the high tide brought about by Typhoon 0416 in the downtown of Takamatsu city. The numerical simulations are carried out using the computational mesh of 12.5m×12.5m withand without the sewerage system.The comparisons with the flooded records clearlyshow that the heavy inundated areas are well reproduced by the present model andthat the numerical simulation taking account of the sewerage system gives betterresults.