Biobeds for reducing the impact of pesticide point-sources of pollution upon water quality entering the Great Barrier Reef Lagoon: a preliminary investigation

Agricultural pesticide point-source pollution negatively impacts the quality of water entering the Great Barrier Reef Lagoon. Mixing sites for sugarcane farm chemicals and spray-tank wash-down areas have been identified as considerable sources of pesticide point source pollution, yet no mechanism of control has been identified. To address the issue, preliminary tests of the efficacy of a form of bioreactor, termed as a biobed system, were undertaken under commercial farming conditions via establishment of two systems within Central region sugarcane farms. Results from three separate events demonstrated the ability of biobeds to significantly reduce the overall concentration of multiple forms of pesticides applied simultaneously and to reduce the concentration of multiple forms of pesticide to below nominated environmental threshold levels. Further work is required to fully address all aspects of biobed operation and function to maximise water-quality outcomes. However, in their current format biobeds were seen to provide a viable option in addressing pesticide point-source pollution and improve water-quality outcomes for the Great Barrier Reef lagoon.