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A risk assessment of water quality pollution of Darwin Harbour using modelled catchment impacts on water quality.



A risk assessment of water quality pollution of Darwin Harbour using modelled catchment impacts on water quality.


Fortune, Julia; Northern Territory., Department of Environment and Natural Resources. Water Resources Division


E-Publications; E-Books; PublicationNT; 6/2018




Darwin Harbour


A semi-quantitative risk assessment was undertaken using outputs of the WQPP-DSS for the 2050 scenario and knowledge of current water quality in conjunction with factors such as land use, point source loads, residence times and typical estuarine categories. The 2050 scenario assumed treated wastewater from urban development in the Elizabeth and Blackmore river catchments would be directed to the Palmerston treatment plant and that discharge water quality would be the equivalent to the base scenario. The risk assessment focussed on the possibility of pressure and stressor elevations occurring over a timeframe of 20 to 40 years in attempts to align with the future development (worst case scenario) outputs.


This report has been funded by the INPEX-operated Ichthys LNG Project.

Table of contents

Summary -- 1. Darwin Harbour -- 2. Risk Assessment of Water Pollution using WQPP-DSS -- 2.1. Catchment planning for estuary response (CAPER) -- 2.2 Limitations of model -- 3. Introduction to scenarios -- 3.1 Base case and 2050 scenario flows and loads -- 4. Summary changes in pollutant loads with scenarios -- 5. Modelled estuary nutrient response map outputs -- 5.1 Modelled base case and 2050 scenario for TN and estuary response -- 5.2 Modelled base case and 2050 scenario for TP and estuary response -- 5.3 Estuarine nutrient response -- 5.3.1 Limitations of TSS evaluation -- 6. Semi Quantitative Risk Assessment -- 7. Conclusion -- 8. References -- Appendix 1: Chronology of point and diffuse loads to Darwin Harbour (2006-2014) -- Appendix 2: Base case - estuary response --Appendix 3: 2050 Scenario estuary response -- Appendix 4. Risk assessment - List of Figures -- List of Tables




Water Quality Pollution; Darwin Harbour modelled

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Northern Territory Government

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46 pages : colour illustrations and maps ; 30 cm.

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