The Australian water balance model

The Australian water balance model (AWBM) is a catchment water balance model that calculates runoff from rainfall at daily or hourly time increments. The daily version iss used for water yield and water management studies; the hourly version is used for design flood estimation. This paper describes the origin and development of the AWBM beginning with elementary modelling components of saturation overland flow. A particular feature of the AWBM is the development of model-specific calibration procedures based on the model structure, including a graphical analysis of rainfall and runoff data, multiple linear regression and an automatic self-calibrating procedure. Application of the model for daily streamflow simulation is illustrated using data from 19 catchments located across Australia. Application at hourly time steps for design flood estimation is demonstrated on three catchments in Victoria. A procedure for use of the model to estimate daily streamflows on ungauged catchments is illustrated using the 19 catchments from the water yield study. Applications of the model in several research programs are described.