Water Tanks in Perth

Perth does it hard when it comes to water. Despite often getting more annual rain than Melbourne, Perth has long periods without rain which can make or break farmers and put significant pressure on the dams. This is most evident 2002 when water reserves dropped to around 19%. Since then, the things have been a little better however Perth still has not had their dams over 50% full for a long time.

The Water Corporation has now turned to alternative water sources such as desalination, recycling, even the concept of a canal from North- West at a cost of billions of dollars.

Even in a bad year Perth gets quite a lot of rain. So, wouldn’t it be better that everyone buy rainwater tanks rather than spend billions of dollars on desalination plants that also need vast amounts of power to run them?

When calculating your water usage and your water tank size you need to allow for a longer period without rain than other capital cities. The average for January is just 8.6mm which is very low in December, January and February not much better. Depending on how much you intend to rely on your tanks, you need to either:

a) get more Supertanks rainwater tanks to increase your storage and help get you through the dry months, or

b) accept that you can only rely on your water tanks for around 70% of the year, and use mains water over Summer when your tanks get low.

To reduce your Mains consumption by 70% is pretty amazing when you think about it. If everyone did that we wouldn’t have a water problem, and we sure wouldn’t need desalination plants!

To make any difference, you need to install a rainwater tank with over 5000-litre capacity. To achieve this volume with Supertanks, you need at least 13 tanks.

The Department of Water offers rebates for tanks and many developers, and local councils are offering incentives for installing tanks. Consult your local council or developer for more information or visit the Waterwise website for current rebates and info about rainwater tanks. You might also like to learn a bit more about the reasons for the water restrictions.

For more information about Perth and Western Australia’s rainfall, or first flush rainwater filters or designing your rainwater tank system, please see our rainwater design guide for rainfall data and water usage in Perth.