With the drought heavily upon us in the Western Cape, alternative water sources are becoming more important than ever. Grey water is water collected after showering, bathing,  using basins, and washing dishes or clothes. (It does not include water from the toilet, which is called black water.)

If you grow your own food, this grey water could be used to water your fruit trees and vegetables.

Growing veggies using household grey water simply makes sense. It saves water in the long run and, with a bit of knowledge about composting, crop rotation, rainwater collection and other gardening topics, you could be well on your way to becoming self-sustainable. Apart from saving money, you’ll also avoid supporting monocrop farming which destroys arable landand and places a heavy burden on water resources.

Grey water contains nutrients like nitrogen and phosphorus, and plants can produce a higher yield if grey water is substituted for normal municipal water. Soapy water can also repel pests like aphids.

It is important to remember to use biodegradable products as many cleaning products can damage or kill your plants. Aside from containing harmful chemicals that can harm humans, animals and plants, many cleaning products on the shelves of supermarkets have also been tested on animals.  It makes sense to diversify our shopping habits and look into more sustainable solutions in the way we live our lives on a daily basis.

There are companies that install grey water systems and these can cost anything from R2 000 to R10 000. We have found that the most affordable and easiest option is to purchase a WaterWarrior for + – R110.  This is a fitting which connects your drain outlet pipe to a 25mm hosepipe.  You can then let the water run straight into your garden. Most drain outlet pipes are 50mm or 40mm in diameter. The WaterWarrior connects to a 50mm drain outlet pipe. However, a 40mm connector ring can be purchased for 40mm outlet pipes.

Things you will need to divert an outlet pipe to the garden:
  • WaterWarrior (and a connecting ring if you have 40mm outlet pipes)
  • Plumbing tape
  • 25mm garden hose or irrigation pipe
  • Clamp

For more instructions on how they are installed, you can watch this video

Important things to remember with grey water:
  • Use grey water within 24 hours. Pathogens can develop if it is stored too long
  • Use biodegradable, environmentally friendly cleaning products
  • Don’t use fabric softener, half a cup of vinegar is the best substitute .
  • Oily water is not good for soil so rinsing pots and pans in a little hot water first is  beneficial
  • Don’t use water from washing nappies or clothes soiled by faeces
  • Don’t use grey water if anyone in the house is suffering from an infectious disease


Written by Aimee Hoppe