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On-site sewage management systems

On-site sewage management (OSSM) systems refer to any system that treats wastewater and disposes of the effluent within the premises. If you live in a house that is not connected to reticulated sewer, you will have an OSSM system.

OSSM systems involve the collection and treatment of wastewater, followed by disposal to an approved land application area (effluent disposal area). This disposal area could be:

  • surface or subsurface absorption
  • an irrigation system
  • a system which uses a holding well and is collected by a tanker.

If your system is not maintained and treated properly, there can be serious adverse effects and impacts. Some of these include the spread of disease, bacteria, virus and pathogens, and contamination of groundwater and surface water.

Major steps in the OSSM system application process

Council's flow chart outlines the major steps in the OSSM system application process:

Approval to install, alter and operate an OSSM system

OSSM systems are regulated jointly by local councils and NSW Health and must be approved by Council before installation. You must ensure your OSSM system is maintained and working well once installed.

If you would like to install a new OSSM system on your property, or alter an existing system, you need to gain approval from Council and submit an Application to Install/Alter and Operate an On-site Sewage Management System.

Council's On-site Sewage Management Code of Practice explains the approvals process and requirements to help you prepare your application:

The Local Government (General) Regulation 2021 (the Regulation) also outlines the documents you need to lodge with your application.

Under the Regulation, Council must not approve of the installation of certain sewage management facilities unless they have been accredited by NSW Health. The types of sewage management facilities to which accreditation applies includes septic tanks, aerated wastewater treatment systems and composting toilets.

Lodge an Application to Install/Alter and Operate an On-site Sewage Management System

There are two ways you can lodge your application:

Prepare your supporting documents

You can lodge a Section 68 application (OSSM) on the NSW Planning Portal as a separate application or as part of a Development Application (DA).

There are various supporting documents you will need to prepare and upload with your application. Some of these include:

Lodge your application on the NSW Planning Portal

Step 1: Prepare to upload your supporting documents

Once you have prepared the supporting documents detailed on this page, you will need to save them as separate PDFs ready to upload with your application.

Please ensure that you have addressed all requirements in the application so that you're not charged another portal service fee to re-submit. The NSW Government issues portal service fees to support the ongoing maintenance and delivery of the Planning Portal.

Please note that fees payable through the ServiceNSW gateway may incur a surcharge.

If you have any queries about portal service fees, please contact ServiceNSW:

  • T:  1300 305 695.

Step 2: Lodge your application and supporting documents on the NSW Planning Portal

Council's Environmental Health Officer will assess your application and where approval is granted, we will provide you with a letter that will include any conditions that apply to these works.

Council will issue you with an invoice for the application fee.

If you choose to apply for approval at the same time as your DA rather than lodge a separate Section 68 Application, you will not be required to pay any additional application fees associated with these works.

Step 3: Pay your application fee

Once you receive an invoice for the application fee, you will need to pay the fee by following one of the payment options detailed on the invoice.

You will need to pay the applicable fee at the time of lodging your application. The current fees are:

  • installation application: $373
  • modification: $102
  • unapproved existing tank: $559

OSSM system risk ratings

All OSSM systems are allocated a risk rating, which determines the frequency of inspections. If you have a sewage management system that has been operating for a while, there is an opportunity to downgrade the risk rating so inspections are required less frequently.

You can apply for this if systems are well maintained and meet these criteria:

  • No defects have been identified for the past three inspections (high risk) or two inspections (medium risk).
  • The property has remained in the same ownership during the above inspections.
  • The property is owner-occupied (not tenanted or holiday rented).

Apply to downgrade your OSSM risk rating

More information

Contact us

If you need more information about on-site sewage management systems, please contact our Public and Environmental Health Team: