Review of toxicity of agricultural chemicals and implications for aquatic fauna of the Keep River

This report was compiled for the Western Australian Department of Primary Industries and Regional Development (DPIRD) as part of the National Water Grid Authority (NWGA) project entitled “Managing water quality to enable future irrigation development in the Kimberley Region, WA”. The purpose of this report is to review the toxicity of farm chemicals (herbicides and insecticides) used by farm operators in the Keep River catchment and their potential impacts on the aquatic species in the river, in particular those species that are listed under the Environment Protection and Biodiversity Conservation Act 1999. It is designed to complement the report entitled “Three-dimensional hydrodynamic modelling to evaluate effect of farm chemicals on the lower pools of the Keep River” compiled by GHD Pty. Ltd., and to inform management of current and future agricultural practices in the catchment. Investigators from Murdoch University, DPIRD, GHD, The University of Queensland and Farmacist presented preliminary results of these investigations into the potential toxicity of agricultural chemicals in use on farms in the Keep River catchment and mitigation and management options to key stakeholders in Kununurra on 29-30 March 2023