Single-flush v. dual-flush

All modern toilets in New Zealand have a dual flush system, giving the user the choice of how much water they require to flush clean the toilet bowl. These use on average around 7 litres per flush. However, older infrastructure that is often found in clubs, more often than not sport old single-flush toilets, which use up to 12 litres of water per flush. The most efficient models on the market, use a mere 4.5 to 6 litres of water per flush.  

What are your options?

  • Gizmos: If upgrading to more efficient dual-flush toilets is impractical or not within the current budget, installing a gizmo is a simple, inexpensive way to conserve water. A gizmo is a lead weight that hangs inside the cistern tube. Once installed, the flush only lasts for as long as the button is pushed. These can be purchased very cheaply at your local hardware store.

  • Upgrading to dual-flush: If you have decided to install a new toilet, make sure you look out for the Water Efficiency Label. Its simple star rating indicates the water efficiency of the product you are looking at - the more stars, the more water efficient it is. It also states the amount of water used per flush so you can easily compare different models on their water efficiency.

  • Grey water or rainwater capture: You can use grey water recycling or rainwater capture systems to provide the water for your toilet flushes. Using rain or grey water reduces the need for and reliance on the mains water supply system, and it reduces the wastewater peak flows discharging to council’s wastewater system. More information on grey water recycling can be found here and rainwater capture here.

  • Waterless composting toilets: In order to completely eliminate the need of water, composting toilets are an alternative. This is an especially interesting option in areas where no means sewer connection is available. However, waterless toilets are not recommended for urban environments!


Leaks from your toilet cistern can result in thousands of litres wasted. A good way to test if you have a leaking toilet is to put a piece of toilet paper on the dry part of the toilet bowl. If this paper ends up wet or even in the bowl’s water without flushing it indicates that you have a leak that should be fixed. Read more on leaks here.

More Information

Go and check out Watercare , Level NZ and Smarter Homes for more great water-saving tips!