The effect of saline lake water disposal from the Lough Calvert Drainage Scheme on water quality of the Barwon River, in south west Victoria, Australia, was investigated. The Scheme is used to regulate the levels of several saline lakes outside the Barwon's catchment. This study found that the disposal of saline lake water was associated with increased total phosphorus, PO4, TKN, suspended solids, electrical conductivity and stream discharge and lower NOx in the Barwon River. Thus, when disposing of saline water, factors other than salinity should be considered in order to prevent an impact on the aquatic environment. At present this is generally not done. The results are discussed with reference to the effects of saline water disposal on aquatic biota and how the effect of saline lake water disposal on water quality may differ from the disposal of saline groundwater.