Grey water as a valuable resource

In times of drought that South Africa is experiencing, instead of releasing your grey water into the sewer lines, your grey water can be utilised in your garden to keep your living space green and benefit the flora and fauna that also suffers in times of drought.

With proper treatment grey water can be put to good use. These uses include water for laundry and toilet flushing, and also irrigation of plants. Treated grey water can be used to irrigate both food and non-food producing plants as the water has not come into contact with faeces, either from the toilet or from washing diapers. Grey water may contain traces of dirt, food, grease, hair, and certain household cleaning products. While the water may look “dirty,” it is a safe and even beneficial source of irrigation water in a yard.

It is advisable to use biodegradable products in the washing machine. The average suburban garden accounts for about 35% of domestic water consumption. Most of the concerns about grey water are to do with the hygiene aspect and odours of the water, but both these aspects are eliminated if the water is re-used as soon as possible and bacteria has not been given the time to produce.


Advantages of using grey water

  • Lower fresh water usage
  • Less strain on septic tank
  • Grey water has effective nutrients for plant life
  • Ground water recharge
  • Cost effective, up to 80% of waste re-used
  • Avoid penalties of water restrictions
  • Connect to existing irrigation


What is the difference between black water and grey water?

Recycled grey water can be used for irrigation and in constructed wetlands while black water is wastewater from toilets. Grey water is wastewater from sinks, dishwashers, bathtubs, and washing machines. Black water is contaminated with disease carrying bacteria, while grey water has lesser contaminants.