INUNDATION MODEL FOR HIGHLY URBANIZED AREA

The flood inundation model for highly urbanized area is different from general flood models due to the increase of the complexity of nature and the internal boundaries. As consequences, the flow is more complex and requires a stable numerical model. Here is a flood inundation model for highly urbanized area (SUIKOU-2D) that meets all those challenges.

Suikou has meaning the flow of water in Japanese. Sui is mizu or water and Kou is Iku or go. Although Japanese don't use this word "Suikou" instead of "Kyuuryuu" or "gekiryuu", this word was especially adopted as a name of this numerical code. SUIKOU-2D was written in FORTRAN-77 for Finite Difference Method, MACCORMACK SCHEME combined with ARTIFICIAL VISCOSITY SCHEME. These schemes allow to smoothly perform a numerical simulation of two-dimensional depth-averaged flow.

This model was tested to simulate and to evaluate the past flood inundation in 2004, Aioi area in Kofu, Yamanashi. It was a heavy storm with 78mm/hr of intensity resulted overflows from drainage channels and yielded a severe inundation in Aioi area.
Compared to the observed data, the numerical result was good. Then, it is supposed to be a useful tool for the water authority and the local government to design the countermeasures, to assess the inundation processes and to provide the potential inundation hazard map.

Result of 1 hour flooding (flood.avi).

An example of inundation process is as follow:


Link:
Sisinggih D., S. Oishi and K. Sunada: Flood Inundation Model for Highly Urbanized Area and Its Application to Simulate the Flood Inundation in 2004, Kofu-City, Japan, Annual Journal of Hydroscinece and Hydraulic Engineering, Vol.52, 2008.2