Wastewater is used water that has been used inside homes, businesses and industries.

Wastewater mostly comes from showers, baths, sinks, washing machines and toilets and is 99.97% water by mass. Wastewater collects in pipes inside a home or business and then travels to a wastewater treatment plant to be cleaned. Wastewater should not be confused with stormwater which, as the name implies, is rainfall runoff collected in storm drains and other catchments.

Treatment process

The treatment of wastewater goes through a number of stages:

  • wastewater enters a treatment plant, where debris and large objects are removed using filter screens, collected and disposed of.
  • wastewater is then transferred into tanks where solid matter sinks to form sludge.
  • the wastewater flows then has oxygen added to help break down and remove any organic pollutants.
  • the remaining wastewater enters into settlement tanks where remaining sludge sinks to the bottom.
  • water is returned into the ocean, recycled for use on the irrigation of gardens and parks, or transported to an Advanced Water Recycling Plant to be further treated, ready to recharge groundwater supplies. 


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Where should your waste go?

Where should your waste go e-learning 

Wastewater - upper primary

e-learning wastewater upper primary

Wastewater - high school

e-learning wasewater high school

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