What are the water quality requirements for effluent released from a wastewater treatment plant into the Marine Park?
The discharge of sewage effluent from fixed structures on islands into the Great Barrier Reef Marine Park is managed under the Sewage Policy 2005 and the Great Barrier Reef Marine Park Regulations 1983. The Policy stipulates that all discharge of sewage effluent from fixed structures into the Great Barrier Reef Marine Park must be of tertiary treatment standard and this standard is outlined in Regulation 135(3): Sewage is taken to have received tertiary treatment if the effluent discharge complies with the following standards: • 5 day biochemical oxygen demand does not exceed 20 milligrams per litre; • suspended solids do not exceed 30 milligrams per litre; • pH value is between 6.0 and 8.5; • dissolved oxygen is at least 2 milligrams per litre; • Escherichia coli bacteria organisms in at least 5 samples of the effluent, collected at intervals of not less than half an hour: • have, in respect of all the samples, a geometric mean value that is not more than 200 colonies per 100 millilit
