Looking after your onsite wastewater management system

Maintaining your system

Under the Environmental Protection Act 2017, the general environmental duty (GED) requires any person engaging in an activity that may cause risk of harm to human health or the environment from pollution or waste to minimise these risks. The GED applies to people who own or use (ie. tenants) a septic tank and how the system is constructed, installed, altered, operated, and maintained. Management of treated wastewater from your OWMS is your responsibility. Older systems, poorly installed systems, and poorly maintained systems can be a risk to human health and the environment; however, correctly maintaining your system will prevent harm and increase the life of your system.


For all systems, Council recommends to do the following to keep your system in good working area:

  • De-sludge the primary septic tank system at least once every 3 years, or sooner if it reaches capacity. 
  • Don’t cover any part of the system with paving, concrete, buildings, garden beds, large trees, vehicles, livestock etc.
  • Ensure that suitable plants and landscaping is maintained over the life of the system. Council can be contacted for a list of suitable plants to be used. If you are planning on changing the landscape of the area, please contact Council before doing so to ensure that it is compatible with the system.
  • Ensure that any maintenance issues identified by a servicing agent are addressed as soon as possible to minimise ongoing damage to the system. 
  • Don’t use any bleach, detergent, or disinfectant unless they are designed for use in an OWMS.

  • Use low phosphorus and low sodium (liquid) detergents to improve effluent quality and maintain the soil’s properties.

  • If your property has a treatment plant (AWTS), have it serviced by a suitably qualified agent at least once every 3 months in accordance with the system manufacturer‘s specifications.


For further information, please refer to the information sheets in the side panel or contact Council's Environmental Health Team.