WHAT IS GREYWATER?

Greywater is used household water from hand-basins, showers, baths, washing machines and kitchen sinks, as opposed to Blackwater, which is water from toilets.

The greywater from the bathroom (hand-basin, shower and bath) is the most suitable source of greywater for recycling as irrigation water. Laundry water is the next most suitable, particularly if a biodegradable detergent is used. One draw-back of using laundry water is where water softeners are used, as their waxy texture may clog the pump and irrigation pipes. More frequent cleaning of filters and flushing of the system is required if laundry water is used in a grey water recycling system. The use of water from the kitchen sink or dishwasher is not recommended as it may contain traces of blood, food scraps and pesticides.

BENEFITS OF GREYWATER RECYCLING

  • Save potable drinking water
  • Save money on water bills
  • Ensure a constant water supply for the garden
  • Reduce the impact on natural water resources by reducing water consumption

HOW MUCH WATER CAN BE SAVED BY RECYCLING GREYWATER?

The average South African household uses 250 – 270 litres of water per person day. As can be seen from the breakdown below, nearly 50% of household water can be recycled.

Toilets37%
Baths & Showers32%
Washing Machine17%
Other eg. cooking, washing dishes and clothes, drinking, etc.14%

 

IS IT SAFE TO USE GREYWATER?

Greywater Recycling has been reused for irrigation purposes for many years all over the world and specifically in countries with very similar climatic conditions to South Africa, such as Australia, Europe (Spain, Denmark), Japan, Israel, Jordan and USA (California, New Mexico and Arizona)

Rand Water and UNISA baseline research shows that the quality of greywater from sample homes in suburbs are all within the parameters of the South African water quality guidelines for irrigation. This means that greywater from your bathroom is safe to use for irrigation in your garden.

HOW IS GREYWATER RECYCLED?

The outlet pipes from the bathroom are diverted to a greywater collection tank.  The water passes through a filter to remove hair, lint and other particles and is then pumped out of the collection tank to irrigation pipes. Greywater should not be allowed to form pools on the surface after watering, if connected to a hose it should be moved regularly to different areas. Any greywater tank should be securely covered to restrict access and to prevent mosquito breeding.

Mini Greywater – suitable 4 – 6 persons                                                                     G-Flow Greywater System

Calcamite Mini G-Flow Cropped

 

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