A large number of properties in the Ipswich area are not connected to a reticulated sewerage system. The treatment and disposal of all wastewater generated on these properties must be undertaken by an on-site sewerage facility.

On-site sewerage facilities

An on-site sewerage facility is any system that stores, treats and disposes of household wastewater on the property. Poorly sited or maintained on-site sewerage facilities can impact public health and the environment. The owner of the facility is responsible for ensuring the system is maintained and functioning properly.

The disposal of effluent (treated sewage) may occur:

  • on the property on a designated area (called a land application area)
  • off the premises by a common effluent drainage system
  • off the premises by collection from a holding tank by a council-approved liquid waste carrier.

A common effluent drainage system is where two or more premises have their wastewater combined (usually after primary treatment) and transported to a common land application area independent of premises where the wastewater was generated. Such systems over 20 equivalent persons would also require approval and further monitoring from the Department of Environment and Science.

Types of on-site sewerage systems

Treatment systems for household wastewater include:

Conventional domestic sewage treatment plants (secondary treatment or better)

  • activated sludge system
  • biological trickling filter system
  • extended aeration system
  • aerated/aerobic sand filter system
  • effluent may be disposed of via trenches, surface or subsurface irrigation

Septic tanks (primary treatment)

  • all-waste septic tank (all household wastewater)
  • black water septic tank (toilet, urinal and bidet wastewater only)
  • greywater septic tank (sullage wastewater only)
  • effluent may be disposed of via trenches only

Composting systems

  • dry vault system (toilet waste only - waterless)
  • wet system (all household wastewater - may be considered a domestic sewage treatment plant)

Holding tank

  • off the premises by collection from a holding tank by a council-approved liquid waste carrier
  • grey water treatment/diversion facility.

Although council approves the installation of an on-site sewerage facility, the treatment system will require product approval from a State Government Department.

Greywater

Greywater is waste water generated from baths, showers, washbasins and laundries which can be diverted for use on lawns and gardens. Kitchen greywater cannot be diverted or reused.  Kitchen greywater must be treated and disposed of in accordance with the plumbing permit issued when the building was constructed.

Greywater can be diverted from laundries and bathrooms by:

  • manual bucketing of untreated greywater (except kitchen greywater)
  • connecting a flexible hose to a washing machine outlet
  • seeking council approval for the installation of greywater diversion device or greywater treatment plant (by licensed plumbers), connected to an irrigation hose.
  • surface or sub-surface system (with council approval).

Care should be taken if reusing greywater because of its:

  • potential health risks to humans
  • potential for environmental damage to soils, ground water, and waterways caused by increased nutrient and chemical levels.

Council approval for greywater diversion and treatment systems

You will need a council permit before installing either:

  • a greywater diversion device, which diverts greywater from the bath, shower, hand basin and/or laundry to an irrigation hose. Untreated greywater cannot be stored
  • a greywater treatment system, which collects the greywater and treats it to a high standard for reuse as garden irrigation.

Information for plumbers

The greywater guidelines for plumbers on the Business Queensland website can help plumbers assess whether the home owner has suitable and sufficient land to distribute greywater.

Fact Sheets