Onsite effluent disposal systems

Effluent Disposal Applications are required for all new dwellings/sheds that are not connected to sewer and for renovations and/or additions to existing dwellings.

Lodging an Application to construct or install an apparatus for the treatment of sewage

(for commercial applications or applications requiring Department of Health approval, refer to below link)

Guide to onsite effluent disposal applications

Who can apply to install an Effluent Disposal System?

Applications can be made by:

Conventional septic system Alternative systems Grey water systems
The plumber Only the approved installer The plumber
The builder  The installer
Earthworks contractors and/or drainers 


When is Department of Health approval required?

If you are applying for a commercial system or a system which is to produce more than 540L of sewage per day, the Shire will refer the application to the Department of Health for approval.

Lodging an Application to the Department of Health

Refer to the below guide:

Health approval required

Conventional Septic Systems VS Alternative Systems

Only a small proportion of our shire has reticulated sewerage. When sewer connection is not available, an onsite effluent disposal system is required.

If you are unsure if reticulated sewerage is available on your property, please contact the Water Corporation’s Technical Advice Line on 13 13 95 for more information.

Due to the number of sensitive environments and ecosystems within our shire, many of the sub-divisions have specific requirements for onsite effluent disposal in order to protect the environment and water systems.

Nutrient retentive effluent disposal systems are an alternative to conventional septic systems. These systems are installed in areas that are environmentally sensitive or where untreated effluent would pose a risk to public health.

Nutrient retentive effluent disposal systems are categorized into one of two types:

  • Aerobic Treatment Units (ATU’s) are a small scale septic system which uses aerobic process to speed up the breakdown of organic matter. The effluent is then further treated and disposed of by either surface irrigation, sub-soil/sub-strata drippers, or leach drain systems. Please note some subdivisions only allow sub-soil/substrata drippers for the disposal of waste water.
  • Nutrient retentive leaching systems have conventional septic tanks which process the solid and liquid wastes. These are connected to leach drains that discharge the effluent into an amended soil bed. The amended soils strips the effluent of nutrients.

List of current approved waste water systems

Greywater Systems

Grey water is wastewater from the bathroom and laundry. The Department of Health has approved a number of “off the shelf” products that can be installed by licensed plumbers or installers.

List of current approved greywater systems

When can I use my effluent system?

You cannot use/move into a residence until a final inspection has been completed by one of our Environmental Health Officers and a permit to use the system has been issued. This must be arranged prior to occupation of the dwelling.

It is the responsibility of the installer of the effluent system (septic tank or ATU) to arrange for this inspection.

Prior to inspection, please ensure that:

  • Power is available and connected to the pump and alarm (if a pump and alarm have been installed).
  • The tanks have been filled with water for at least 24 hours before inspection. The lids to the units have either been removed or opened.
  • The pipe work into the tanks has been left exposed.
  • All other conditions as specified on your approval have been completed.

If items are still outstanding at the final inspection a re-inspection may be required. A re-inspection will incur a fee of $109.50 per hour.

Once the Apparatus has been inspected and commissioned, a Permit to Use will be issued to the Installer and a copy sent to the Owner and Builder if applicable.

Additional references and links

Understanding septic tank systems 

Aerobic treatment units (ATU’s)

Trade wastewater

Phosphorus Free Detergent Register

Wastewater system loading rates

Wash Bay Guidelines

For further information, please contact Health Services on 9526 1111 or by email info@sjshire.wa.gov.au