Rainfall-Runoff Processes in Tropical Urban Environments

Abstract

This study used Genetic Programming to establish a modular model consisting of two sub-models: (i) a baseflow module and (ii) a quickflow module to simulate the two hydrograph flow components. The relationship between the input variables in the model (i.e. meteorological data and catchment initial conditions) and its overall structure can be explained in terms of catchment hydrological processes. Therefore, the model is a partial greying of what is often a black-box approach in catchment modelling. Subsequently, this study used the modular model to predict both flow components of events as well as time series, and applied optimization techniques to estimate the contributions of various land uses (i.e. impervious, steep grassland, grassland on mild slope, mixed grasses and trees and relatively natural vegetation) towards baseflow and quickflow in tropical urban systems. This quantification facilitates the integration of water sensitive urban infrastructure for the sustainable development of water in tropical megacities.