The research reported in this paper is focused on the cost-effectiveness of intervention strategies to reduce pollution loads and improve water quality in South-east Queensland. Strategies considered include point and non-point source interventions. Predicted reductions in pollution levels were calculated for each action based on the expected population growth. The costs of the interventions included the full investment and annual running costs as well as planned public investment by the state agencies. The results show that the cost-effectiveness of strategies is likely to vary according to whether suspended sediments, nitrogen or phosphorus loads are being targeted.