Rainfall-runoff modelling in small and middle-large catchments - An overview

Abstract

A rainfall-runoff modelling is nowadays a dynamically developing department of hydrology and water management. This development is caused by a rapid progress of computers and information technologies. This evolution provides the mankind with new possibilities to use water as its basic need and at the same time to evolve an effective protection against it. The aim of this article is to give some basic information about rainfall-runoff modelling, various approaches to it, methods and possibilities of application. This kind of information may help the user with the choice of the suitable rainfall-runoff model. Rainfall-runoff or hydraulic models have many different applications, e.g. in operational hydrology, water resource management or in research. Typical structure of any rainfall-runoff model, come out from a simplified catchment structure as a system of vertical ordered reservoirs, which form a linear cascade model. The main reservoirs are precipitation, evapotranspiration (together with interception), direct runoff, runoff in unsaturated zone (interflow), base flow and channel flow. For computation of processes running in each of these reservoirs (filling or drainage), many equations (model techniques) are applied. This structure and presented modelling techniques are used in the most common models like HEC-HMS, MIKE-SHE, Sacramento (SAC-SMA), NASIM, HBV and many others.