Septic Systems

Regardless of the type of property, any waste water needs to be disposed of in an approved manner, usually via connection to a sewerage system. In areas where reticulated sewerage is not available, an approval to install onsite effluent disposal system is required.

Onsite effluent disposal refers to the treatment and discharge of waste water from properties onsite. Most effluent disposal systems used and installed are septic tanks and leach drains. The type and size of system will depend on a number of factors including the scale of development, volume of wastewater produced as well as environmental factors such as type of soil and proximity of water bodies or groundwater.

Before an onsite effluent disposal system is installed, an application must be lodged with The City’s Environmental Health Department which will then be assessed subject to approval conditions for compliance to the Health (Miscellaneous Provisions) Act 1911.

How do I lodge my application and pay fees?

Applications are to be submitted using the City's application form. Each application must be accompanied by payment of the required fee.

View the Application to Construct or Install Sewage form.

Each application must be accompanied by 2 sets of plans where City approval only is required and 3 sets of plans where approval from the Department of Health is required. Drawings are to include the following;

  • Scale of drawing, either 1:100, 1:200 or 1:500
  • Location of effluent disposal system and all drains and pipework
  • Distance of the system from all buildings, boundaries, bores, waterway and waterbodies
  • Distance of system from all trafficable areas
  • Site plan to have contour lines indicating the slope of the land

Note: Any change from what has been approved must be supported by the City before installation, which may require the submission of amended plans.

Final Inspection and Permit to Use

Upon completion of the installation of the system and prior to it being used, it must be inspected and passed by The City. To arrange an inspection please contact the City to make an appointment.

If the system has not been installed exactly in accordance with the approved plans then ‘as constructed' plans must be provided to the City. Where the system in question is an Aerobic Treatment Unit a 'Certificate of Installation' is also required to be submitted.

Once the system has been inspected and passed, the 'As Constructed' plan submitted and if required the 'Certificate of Installation' then the City will issue a 'Permit to Use'.

Note: It is an offence to use a system without a permit to use.

What do I need to do to decommission a septic tank?

When a developed property is connected to sewer, usually under the infill sewerage program, any onsite effluent disposal systems such as septic tank and leach drain/soak well systems will eventually require decommissioning. This means that the contents of the tank are pumped out (by an approved contractor) and the system is either removed or backfilled. If the system can’t be removed, the tanks should still be pumped out and the bottom of the tanks can be broken up and the system backfilled with sand.

As there are costs involved in both decommissioning a septic tank and connecting to sewer, householders are not automatically required to decommission tanks when they connect to the sewer.

However under the Health (Treatment of Sewage and Disposal of Effluent and Liquid Waste) Regulations 1974, decommissioning is required when:

    • The property is sold
    • The use of the development changes e.g. from a residence to a child care centre
    • Building extensions may encroach on minimums setback requirements from the system.

Septic tanks which have not been decommissioned should not be paved or built over without approval from the relevant local government.

For further information on requirements around decommissioning septic tanks, visit the Department of Health website.