Rainfall-runoff processes and modelling

Hydrological studies of rainfall-runoff processes provide the basis for estimating design flows for urban stormwater drainage systems which control floods and the transport of sediments and pollutants. This paper outlines the theory of urban rainfall-runoff processes and describes the development of modelling practice and the current use of computer models. It concludes that rainfall-runoff theory has reached a mature stage, and highlights deficiencies and dilemmas which require further research, including rainfall variability, scale effects and interfacing between models.