Wastewater treament

Care & maintenance of septic tanks / wastewater treatment systems

Many factors may contribute to septic/wastewater system failure, including:

  • Too much wastewater, especially in surges.
  • Using chemicals which kill decomposing bacteria in the system e.g. disinfectants, detergents, bleaches (minimal use is recommended).
  • Extended periods of rainfall.
  • Excessive shadowing or compacting of the evapo-transpiration area.
  • Leaking plumbing which overloads the system.
  • Tree roots growing into and plugging trenches.
  • Inadequate disposal area.
Waste water drainage pipe Water tank Water outlet


All aerated wastewater treatment systems must be inspected by an approved company every three months to maintain sufficient chlorine in the system and ensure the system is working satisfactorily

Pittwater Council has introduced compulsory inspections to be carried out by qualified contractors with the relevant paperwork to be completed and forwarded back to Council for approval. Property owners are notified by Council when inspection is due.

System maintenance

Septic tanks produce a sludge that collects on the bottom of the tank and a floating scum on the surface of the liquid.

The primary septic tank will require a pump-out every five to ten years, depending on the load. Failure to clean out a tank when required may cause scum to be carried out of the primary tank and into the disposal system.


Do your bit to reduce compulsory blood donations and possible infections by screening all inlets and outlets to your tank — including the overflow pipe. Also have a look around outside and remove any containers that could collect water, such as trays around pot plants.