Rainwater Tanks and Pumps
There isn’t much in life that is free. Rainwater is an exception – it has an economic value and its free!
Assume that you are a resident of Sydney – you own an average-size detached house with a roof area of 250 square metres, and you harvest rainwater from the entire roof area. With Sydney’s average annual rainfall of 1,125mm, you can collect over 280,000 litres of water. If you used 280,000 litres of mains water, that would cost over $650.
Yes, there’s a cost to a rainwater tank, accessories, and installation, but in most cases the payback is quick.
You can use rainwater from a tank anywhere that you use mains water.
You can use rainwater direct from the tank for watering your garden, washing down decks and cleaning cars. With a simple, low-cost filter system, you can use rainwater for drip irrigation and sprinkler systems, and for some indoor uses such as flushing toilets, laundry, and showers. If you treat rainwater with a multi-stage filter to remove all particles and a UV filter to kill pathogens, it is safe for human consumption. Particle and UV filters are available as integrated units and are quick and easy to install.
What happens if you connect your rainwater tank to your domestic supply and your tank runs dry or a power failure stops your pressure pump delivering water to the house?
Luckily, there is a device that allows you to switch from your rainwater supply to mains water. It is called a Mains Water Switch Device and it is installed between the pressure pump, your mains supply, and your house inlet.
The switch device will always prioritise the use of rainwater over mains water so you can use your tank water supply first and then automatically switch to mains water supply if your tank is low or empty or in the event of electrical failure. Once rainwater has been replenished or power has been restored to the pump, the switch will automatically revert back to rainwater.