Approved wastewater systems

The Department of Health is consulting on a draft code of practice for on-site wastewater disposal. The aim is to adopt the code of practice within future wastewater regulations to be created under the Public Health Act 2016. You are invited to provide feedback. Review the consultation page (external site) for more details. Submissions close 4.00 pm 28 September 2023. 

Only approved wastewater systems can be used in WA. Premises owners who install an unapproved system contravene the Health (Treatment of Sewage and Disposal of Effluent and Liquid Waste) Regulations 1974 (external site).

The Department of Health (DoH) requires certification for all onsite wastewater treatment systems against the relevant Australian Standard as detailed in the table below:

Type of Onsite Wastewater System Capacity (L/day) Standard
Precast concrete septic tanks 6000 AS 1546.1 or *DoH approval
Glass fibre-reinforced plastic or plastic septic tanks 6000 AS 1546.1
Waterless composting toilets N/A AS 1546.2
Secondary treatment systems  5000 AS 1546.3:2017
Greywater treatment systems 1000 AS 1546.4

*DoH approval as per Appendix 1 of Code of Practice for Product Approval of Onsite Wastewater Systems (2013)

All onsite wastewater treatment systems with the hydraulic capacities below the volumes in the table must be approved by the DoH. The approved onsite wastewater treatment systems are listed below. On how to obtain certification of wastewater system against the relevant Australian Standard please refer here.

Onsite wastewater treatment systems with capacities exceeding the volumes presented in the table require engineering certification to accompany each application to install the system. It is recommended to submit an engineering certification for each system model at once so that the documentation is on the DoH records  for any future applications.

The DoH will approve and publish onsite wastewater treatment systems with capacities above volumes listed on the table that have StandardMark certification to the relevant Australian Standard. 

Approved wastewater systems include:

Last reviewed: 02-08-2021
Produced by

Environmental Health Directorate