Two separate Source models were developed to address the requirements of the Murray Darling Basin Authority for the ACT Water Resource Plan. These models were developed using consistent data sets and were calibrated using consistent approaches. The catchment model was set up to evaluate results across different land use, management practices and climate scenarios at monthly to annual time steps. It was well calibrated and provided a good estimate of pollutant loads in four different scenarios and can be easily modified to represent future rural and urban runoff management actions (e.g. urban stormwater improvement) without compromising overall model accuracy. The water resource model was constructed to represent each WMA and each of the components of ACT’s net take. The model development was focussed on the ACT; however, the Source model has been created to represent the entire Upper Murrumbidgee River catchment upstream of Burrinjuck Dam.