Developing Probabilistic Floodplain Inundation using Hydraulic Model

Estimating flood hazard in areas subject to flooding from rivers is the basis of many hydrological studies. An estimate of the spatial dimension of the flood event is implicitly deduced from these stages. This study focused on the determination of producing flood plain map from different Annual Rainfall Intensity (ARI) and hydraulic. A numbers of flood plain map were designed using ArcView GIS 3.3 with extension of HECGeoRAS and by using HEC-RAS as hydraulic model. While CCHE2D model visualise the flood extend in 2D and as a comparison with HEC-RAS. Results show that different storm events produced different flood plain extent. As the increase of storm events from 2 years of storm event in 1 hour to 100 years of storm events in 1 hour, the flood plain maps extent were increased both for predevelopment and post development. Therefore, there is the limit in producing a flood plain map. In view of this, research into flooding represents a pressing concern and should be seen as one of the most important applied roles of the hydrological sciences and as a tools towards sustainability development of the ecosystem.