Onsite wastewater treatment plants must meet the appropriate standard set by us. 

Appropriate standard is: An onsite wastewater treatment plant type must be assessed by a body accredited under the Joint Accreditation System of Australia and New Zealand or any other accreditation body approved by the Authority (assessment body). The assessment body must certify the treatment plant as conforming with the relevant Australian and New Zealand standard (appropriate standard).

These standards are:

• AS/NZS 1546.1: 2008, Onsite domestic wastewater treatment units, Part 1: Septic tanks
• AS/NZS 1546.2: 2008, Onsite domestic wastewater treatment units, Part 2: Waterless composting toilets
• AS 1546.3:2017, Onsite domestic wastewater treatment units, Part 3: Secondary treatment systems
• AS 1546.4:2016 Onsite domestic wastewater treatment units, Part 4: Domestic greywater treatment systems.

An application to your local council for a permit to construct, install or alter and onsite wastewater management system must include a certificate of conformity with the relevant standard. Find a list of all onsite wastewater systems that hold an Australian Standard  certificate .  

In some circumstance, we may grant an exemption from the requirement for a treatment plant to have a certificate of conformity. This may relate to innovative onsite wastewater treatment plants. Read about the section 459 exemptions.

Appropriate standards for onsite wastewater treatment plants

Types of onsite wastewater treatment plants	Appropriate standard
Septic tanks (and vermiculture systems)	AS/NZS 1546.1: 2008, onsite domestic wastewater treatment units, Part 1: Septic tanks.
Waterless composting toilets	AS/NZS 1546.2: 2008, onsite domestic wastewater treatment units, Part 2: Waterless composting toilets.
Secondary treatment systems (including sand filter treatment plants)	AS 1546.3:2017, onsite domestic wastewater treatment units, Part 3: Secondary treatment systems
Domestic greywater systems	AS 1546.4:2016 onsite domestic wastewater treatment units, Part 4: Domestic greywater treatment systems. (Note: AS 1546.4:2016 was adopted in the legislative framework on 21 November 2016).