Application of the random walk theory for simulation of flood hazards: Jeddah flood 25 November 2009

Abstract

Hydrological and hydraulic modelling are becoming essential in the field of flood hazards. There are many models available in the literature among them HECHMS, MIKESHE, HECRAS, MIKEFLOOD, MIKE11, SWMM, DELFT3D, etc. Each of these models has its own advantages and disadvantages. In general, hydrological models are used to estimate the flood from a rainstorm, while hydraulic models are used to delineate the inundation zones. Solution of the governing equations for flood propagation is cumbersome and takes lots of time and efforts especially in two-dimensional domains in urbanised areas. In this paper, an efficient methodology based on the random walk theory is developed and programmed to delineate the inundation areas from a flood. The method is applied on the flood that happened on November 2009 in Jeddah city using a simplified city configuration. The results are plausible. The method can be further developed to simulate floods in a real city configuration.