2 Table of Contents Acknowledgements ................................................................................................................................. 9 Executive Summary ............................................................................................................................... 11 1 Introduction ..................................................................................................................................... 16 1.1 Why is a Water Quality Improvement Plan needed? ........................................................... 16 1.2 Overview and scope .............................................................................................................. 17 1.2.1 Catchment and marine boundaries .............................................................................. 18 1.2.2 Freshwater ecosystems ................................................................................................. 18 1.2.3 Sediment, Nutrient and Pesticide Loads ....................................................................... 18 1.3 Approach, supporting projects, previous work .................................................................... 19 1.4 Governance and stakeholder engagement ........................................................................... 19 1.5 Queensland Legislation and Policy........................................................................................ 20 1.5.1 The Great Barrier Reef Water Quality Protection Plan ................................................. 22 1.5.2 Reef 2050 Plan .............................................................................................................. 22 2 Catchment characteristics ............................................................................................................... 24 2.1 Location and landscape......................................................................................................... 24 2.2 Climate .................................................................................................................................. 25 2.3 Cyclones, storms and flooding .............................................................................................. 26 2.4 Geology, soils and topography.............................................................................................. 26 2.5 Hydrology .............................................................................................................................. 27 2.6 Land use ................................................................................................................................ 28 2.7 Socio-economic profile ......................................................................................................... 30 2.8 Basin Summaries ................................................................................................................... 31 2.8.1 Baffle ............................................................................................................................. 31 2.8.2 Burnett .......................................................................................................................... 31 2.8.3 Kolan ............................................................................................................................. 32 2.8.4 Burrum .......................................................................................................................... 32 2.8.5 Mary .............................................................................................................................. 32 3 Marine and Coastal Ecosystems ...................................................................................................... 34 3.1 Great Barrier Reef ................................................................................................................. 34 3.2 Great Sandy Strait ................................................................................................................. 34 3.3 Ecological Values ................................................................................................................... 35 3.3.1 Seagrass......................................................................................................................... 35 3.3.2 Dugong .......................................................................................................................... 36 3 3.3.3 Turtles ........................................................................................................................... 37 3.3.4 Coral Reefs .................................................................................................................... 37 3.3.5 Cetacean ....................................................................................................................... 37 3.3.6 Birds .............................................................................................................................. 38 3.4 Assessing the value of the marine ecosystems ..................................................................... 38 3.4.1 Determining value of the Burnett Mary marine ecosystems ....................................... 38 4 Threats to marine and coastal values .............................................................................................. 41 4.1 Water quality issues and principal causes ............................................................................ 41 4.2 Climate change ...................................................................................................................... 42 4.3 Current water quality status ................................................................................................. 43 4.3.1 Total Suspended Solids (TSS) ........................................................................................ 43 4.3.2 Dissolved Inorganic Nitrogen (DIN) ............................................................................... 44 4.3.3 PSII Herbicides ............................................................................................................... 45 4.3.4 Particulate Nitrogen (PN) .............................................................................................. 45 4.3.5 Dissolved Inorganic Phosphorus (DIP) .......................................................................... 46 4.3.6 Particulate Phosphorus ................................................................................................. 47 4.4 Water quality risk assessment .............................................................................................. 47 5 Approach and integration ................................................................................................................ 49 5.1 Economics of sugar cane and grazing ................................................................................... 50 5.1.1 Sugar Cane .................................................................................................................... 50 5.1.2 Grazing .......................................................................................................................... 51 5.2 Bioeconomic Modelling ........................................................................................................ 51 5.3 Benefit:Cost analysis using INFFER ....................................................................................... 52 6 Water quality targets and program logic ......................................................................................... 54 6.1 Reef Plan targets - apportioned to Burnett Mary ................................................................. 54 6.2 Ecologically based targets ..................................................................................................... 55 6.3 Implementation Targets for this WQIP ................................................................................. 55 6.4 Program logic linking water quality and protecting values .................................................. 57 6.5 The link between values, water quality objectives and program logic ................................. 58 7 Addressing water quality by reducing land use impacts ................................................................. 60 7.1 Contributing major land uses ................................................................................................ 60 7.1.1 Total Suspended Solids ................................................................................................. 61 7.1.2 Particulate nutrient losses ............................................................................................ 62 7.1.3 Dissolved Inorganic Nitrogen ........................................................................................ 62 4 7.1.4 Dissolved Inorganic Phosphorus ................................................................................... 63 7.1.5 Dissolved Inorganic Phosphorus ................................................................................... 64 7.1.6 Pesticides (PSII Herbicides) ........................................................................................... 65 7.1.7 Other pollutants ............................................................................................................ 65 7.2 Reducing agricultural impacts BMPs in grazing and sugar cane ........................................... 66 7.3 Reducing urban impacts.......................................................................................................