Rain Water Harvesting

Rainwater Tanks are an eco friendly way of harvesting rain water which would normally run off your roof and down your drains. The harvested water is captured from your drains, filtered and stored in the tank for on-demand use for flushing toilets, garden irrigation, dish washing, clothes washing etc. The system typically comes with a pump to direct water via the plumbing to a specific point of use.

What you need to know:

  • Make sure the tank design is aesthetically pleasing to fit the overall dimensions and look of your home. Some tanks can be an eyesore by size, shape and colour
  • Rainwater is a clean source of water – a water treatment system is not required if harvested water is only used outdoors. Water must be treated if plumbed for indoor use
  • The system ensures water supply in the event of water restrictions or municipal water switch off
  • It is generally accepted that  1mm of rainfall over 1m2 will give you 1 litre of rainwater
  • Harvested water can also be used for human consumption with the correct filtration treatment inside the tank
  • Payback period is typically 10 to 15 years but this will reduce as water supply becomes more expensive
  • Water is typically pumped to the point of need by a small pump system
  • The system can be connected to your garden irrigation scheme and also used for washing your car
  • A 2000 litre tank will be adequate for a small to medium size garden


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