Author(s): Carlos Arturo Martinez Cano, Arlex Sanchez, Zoran Vojinovic, Oscar Hernandez
Keywords: Infiltration models; Numerical models; Urban flood modelling; 1D-2D coupled modelling;
Abstract: Over the past decades, there have been an increasing need to manage urban flooding. It is normally generated by the expansion of impervious areas and increased localized heavy rains. In urban flood modelling, the effect of infiltration has been normally considered to be not significant, minimum in relation to the rainfall or in most cases simplified to a constant infiltration rate. This paper presents a new and simplified modelling concept to evaluate the effect of infiltration on urban flooding. The evaluation is achieved by coupling a Non-Inertia 2D flood inundation model with a sewer network model through dynamic link libraries. An algorithm to simulate infiltration using the Green-Ampt method is included in the 2D model. The infiltration behaviour is expressed as a function of soil water content and the infiltration rate decays with time. The coupled models were compared to the results of a coupled 1D/2D model built in MIKE URBAN. Infiltration simulations were compared to previous measured experimental data. The results obtained suggest that this approach could be effective to provide quantitative performance values to support decision making as an alternative tool for modelling and evaluating rehabilitation measures. It also shows the importance of incorporating surface water infiltration process into the urban flood models.