Septic or on-site wastewater management

In areas where reticulated sewer is not available, all household wastewater must be treated and contained within the boundaries of the property. This is done through the use of on-site domestic wastewater systems including septic tanks and secondary treatment systems.

Septic tanks installations and alterations

Council must issue a permit before the installation or alteration of a wastewater system. Your plumber may provide you with general information regarding the wastewater treatment system suitable for your property however if you require specific details regarding on-site wastewater treatment options and installation requirements refer to the Environmental Protection Authority (EPA) website.

Installation or Alteration of an Onsite Waste Management System:

OWMS Application Form and Guide(PDF, 462KB)

Council will only issue a Permit to Install for EPA approved wastewater systems

Application Process

The following is an outline of the on-site wastewater application and installation process:

Step 1

Once a planning permit has been granted and prior to works commencing on the building, a Permit to Install must be obtained from the Environmental Health Unit. This must be obtained prior to any installation or alteration to a wastewater system. It is illegal to install a wastewater system without Council approval.

Step 2

Initial inspection and assessment of the property will be conducted by Council's Environmental Health Officer (EHO) to assess the suitability of the proposed installation. This is a time whereby owners and plumbers can liaise with an EHO prior to installation and discuss any queries, options or issues that may arise. In some cases you may be required to provide additional information regarding the site and/or the proposed system for installation. Small lot sizes, steep slopes, flood prone areas or areas known to have poor draining soils, nearby surface water, shallow depth to bedrock or a high water table, may require a Land Capability Assessment as part of the planning process. If the EHO is then satisfied that the proposed system and area are adequate, a 'Permit to Install' will be issued. The "Permit to Install" should be attached to your Building permit application documents.

Step 3

The installation of the septic system must be carried out by a registered plumber. Prior to back filling when installation is nearing completion, a second inspection by an EHO will need to be arranged to ensure the system has been installed in accordance with the Environment Protection Authority (EPA) Septic Tanks Code of Practice and the relevant conditions on the Permit to Install. 

Step 4

If the EHO is satisfied that the system has been installed correctly, an Approval to Use will be issued which will highlight any conditions of use and maintenance requirements that must be followed to ensure correct functioning of the system. A Certificate of Occupancy will not be issued for the property, by the relevant Building Surveyor, unless an Approval to Use for the wastewater system has been granted. Maintenance is required for your septic tank or a secondary treatment system to continue to operate in a safe and environmentally friendly manner.    

It is your responsibility to manage the wastewater from your septic system and/or treatment plant. 

Tips for maintaining your septic or onsite domestic wastewater management system

Poorly installed or maintained systems can be a risk to human health and the environment. The general environmental duty (GED) requires you to manage your onsite wastewater management system to reduce the risk of harm to the environment or human health. 

How to keep your system working well   

  • Make sure your system can be easily accessed
  • Maintain the system regularly. Keep all maintenance record - Council can request to see them 
  • Use licensed plumbers to check if your system needs cleaning and unblocking
  • Desludge the system every three to five years. How often depends on how much the system is used
  • Maintain the disinfection chamber. This chamber uses chlorine to disinfect the treated water. Chlorine tablets must be fitted to the dispenser in the right way. If fitted with UV disinfection, UV light tubes must be cleaned regularly
  • Have an accredited servicing agent install an alarm to warn you of breakdowns
  • Don’t drive vehicles over any part of the system
  • Don’t allow stormwater to discharge into the onsite system or over the disposal/drain field
  • Don’t cover the tank or drain field
  • Don’t place non-biodegradable items or rubbish into the system. Bacteria and other organisms can't break down these items or rubbish
  • Follow any local council maintenance requirements.

Reduce sludge build up in the tank

  • Scrape all dishes to remove fats and grease before washing
  • Don't put solids in the system
  • Don't use a food waste disposal unit unless your system can carry the extra load
  • Don't put hygiene products in the system. For example, sanitary napkins and tissues.

Keep bacteria working well

Not all bacteria are harmful. Some of the bacteria in your onsite wastewater management system converts your waste to liquid and gas.

  • Use biodegradable soaps and detergents that are low in phosphate. Phosphates feed algae that pollute waterways
  • In dispersive soil areas, use detergents that are low in sodium
  • Use the right amount of detergents
  • Don't put chemicals or paint down your drains.

Avoid powerful chemicals

  • Powerful bleaches, whiteners, nappy soakers, spot removers or disinfectants can impact how well your system works. Try to avoid using them.

Reduce the amount of wastewater you produce

  • Install water saving fittings
  • Take showers instead of baths
  • Wash only full loads of clothes.

Avoid overloading your system 

  • Space out your water use
  • Don't do all your washing in one day
  • Don't run your dishwasher and washing machine at the same time.

 

Failing Systems

You must monitor your onsite wastewater management system for signs of failure, especially older systems. Owners and occupiers, including renters, have a legal obligation to report system failures to the local Council. You must take steps to address any issues as soon as possible. Warning signs include:

  • foul smells coming from or near the system
  • slow running toilets or drains
  • full or blocked grease trap
  • wastewater runoff from the disposal area
  • wastewater pooling on the disposal field's surface.

 

Decommissioning your Septic Tank

If your property is connecting to reticulated sewer or you are replacing an old system, the septic tanks must be decommissioned. 

All works must be carried out by a licensed plumber in accordance with EPA guidelines. 

The plumber will ensure the tanks are properly cleaned, disinfected and filled and pipes are permanently sealed. 

You will be required to send a copy of the decommissioning certificate to Council.