You will need approval to construct or install liquid waste, effluent and sewage treatment apparatus including septic tanks, aerobic treatment units, compost toilets or any other sewage treatment apparatus.
Apparatus will need approval from local government if they service a single dwelling, or buildings that produce less than 540 litres of sewage per day.
If they service multiple dwellings, or more than 540 litres of sewage per day, you will also need approval from the Department of Health. These applications must be accompanied by a report from the council on whether approval should be granted (a local government report).