Abstract

This paper analyses the sensitivity of flood inundation due to levee breach against breach model parameters. A parametric levee breach model integrated into the 2D hydrodynamic numerical model Telemac-2D is used to simulate a levee breach flood event at Wonji, Ethiopia. Levee breach process parameters are systemically varied to find out their effect on the modelled flood inundation.The analysis of the model results show that the modelled flood inundation is sensitive to the final breach dimensions and breach location. However, the parameters describing the levee breach development have negligible influence on the modelled flood inundation. This implies that final breach dimension and breach location in an event of levee breach are the most important and decisive factors affecting the resulting inundation of the flood plain and as such should be given due consideration when creating flood inundation maps due to levee breach modelled by employing parametric breach model.