Septic tanks and treatment systems

Onsite sewage management systems

If your home is not connected to a reticulated sewer, you are likely to have some type of Onsite Sewage Management System (OSMS). Onsite sewage management is often referred to as decentralised sewage management. An OSMS is any system that stores or treats sewage. 

The following provides essential information to residents regarding onsite sewage management:

  •  Onsite sewage management monitoring program
  •  Registering your onsite sewage management system/approval to operate
  •  Maintaining your septic system
  •  Installing an onsite sewage management system
  •  Types of onsite sewage management systems
  •  Forms and Fact Sheets
  •  Useful links and references.

Monitoring program

It is a regulatory requirement that onsite sewage management systems by regulated by the council within its local government area. Council's onsite sewage management monitoring program was developed under the guidance of the Offices of NSW Health and Local Government and is detailed in the Onsite Sewage Management Strategy (link to Your Council/A-Z Strategies/On-site Sewage Management Strategy). The Strategy outlines the objectives, goals, legislation, inspection program, fee structure and operational conditions.

Registering your system

All systems must be registered with Council and the owner to be in possession of an Approval to Operate. Council approval is also required for the installation or alteration of a system. 

Existing systems

If you have an existing system that is not currently registered with Council, you must submit an Application for Approval to Operate an OSMS. By lodging the application you will be granted interim approval until such time as Council has carried out an inspections of the system. Following inspection, providing the system complies with Council's requirements, the system will be allocated a risk category and inspection frequency. If the system is not satisfactory, Council will advise what needs to be done to gain approval to operate.

New systems

If you are installing a new system, a Sewage Management Facility Application form must be lodged with Council. An Application for Approval to Operate an OSMS must also be submitted to Council prior to commissioning the system. The installation must be inspected by Council before you move into your home. Upon a satisfactory inspection, Council will then issue you with an Approval to Operate.

New owner

If you have recently purchased a property with an OSMS, you will need to submit an Application for Approval to Operate an OSMS within two (2) months of the transfer of title.  Council does not immediately receive property transfer information from the NSW Land & Property Information Office, therefore it is recommended that you submit an application to Council as soon as possible after your purchase.

Septic systems

The Easy Septic Guide is a booklet that provides information on your responsibilities, how to check your system, easy maintenance tips, types of systems and what can be planted in disposal areas.

For further support with common septic system problems, contact a NSW Health Accredited Systems Installer or Maintenance Contractor - On-site sewage system contacts (Septic Installation/Maintenance Contractors (PDF 41.3KB)

Installing a septic system

Council approval must be obtained prior to carrying out any work on an OSMS. If approval is related to a new building, approval to install an OSMS is usually required prior to gaining a Construction Certificate. For further information, download the Fact Sheet - Installing/Altering a Septic System.

Types of septic systems

There are many different systems available, including:

  •  Septic tank and absorption trenches
  •  Septic tank and evapotranspiration areas
  •  Septic tank and aerobic sand filters
  •  Aerated wastewater treatment systems (AWTS)
  •  Septic tank to pumpout
  •  Dry composting toilets and greywater treatment systems
  •  Wet composting toilets and subsurface application systems
  •  Septic tank and constructed wetlands
  •  Septic tank and soil mound systems
  •  Pit toilets
  •  Pump to sewer systems
  •  Greywater treatment systems
  •  Any other system that stores, treats and/or disposes of sewage and wastewater onsite

When choosing a septic system the most important thing to consider is how it will be used and who will use it. Each user and site may have different factors which will determine the type of system most suitable. 

Under the provisions of Clauses 40 and 41, Local Government (General) Regulation 2005, a local council must not approve the installation of a sewage management facility unless it has been accredited by NSW Health. For further information on accredited systems, visit NSW Health or contact Council. 

Forms and fact sheets

Useful links and references

Below are some useful links and references to government departments, legislation and guidelines relating to onsite sewage management.

Last Edited: 20 Mar 2017