The main difference between rural and urban area inundation is the existence of an impermeable layer and the complexity of the road and building configuration. Therefore, although surface overland flow can be appropriately simulated by the two-dimensional diffusive model in a rural area, there also is a need for a more accurate and elaborate simulation model. In this study, we simulated homogeneous and non-homogeneous mesh types to estimate the effect of road networks and building groups. Two-dimensional run-off flow model and one-dimensional slot-model simulated ground surface run-off flow and sewer pipe flow. To connect both models, we used a newly suggested bi-directional model and its coefficients (LEE et al., 2013). The simulated results showed a non-homogeneous case could calculate more reasonable results; the results further reveal the importance of using storm drains as exchange spots in the model.