Uses for Rainwater

Rainwater can be used instead of mains drinking water for a number of activities in the home. Here are some instances where you can be confident in using rainwater as an alternative water source.

In order to get good use out of a rainwater tank and maximise its value, you should consider connecting it for some indoor usage such as toilet flushing and in the laundry. This way you can use the tank all year round and particularly during the winter months when outdoor use is at a minimum.

Water Wise Rules apply from 1 July 2014. They do not apply to water from rainwater tanks, provided the rainwater tank is not connected to or topped up by the drinking water system. However, rainwater tank users are still encouraged to save water.

Rainwater tanks should NOT be used as a means of supplying drinking water in urban areas due to traffic and industry emissions that can settle on roofs.

Garden watering

The percentage of household water use in the garden varies from less than 25% to more than 50% across Australia, generally depending on a household's geographic location.

Large rainwater tanks tend to be more beneficial as you can store a large amount of water to get through longer dry periods without using potable water.

Where space is an issue, you may wish to consider a different style of tank or installing two smaller tanks.

You can use a sprinkler or watering system to water your garden or lawn with a rainwater tank at any time of day provided that your rainwater tanks is not connected to or topped up by the drinking water system.

Toilet flushing

A toilet can use up to 12 litres per flush and connecting the tank to the toilet system can lead to major water savings. An average person uses 30 litres of water in the toilet per day or 210 litres per week.

You can install an automatic diversion directly from mains water if the rainwater tank is empty. Alternatively, a trickle top up system uses a float valve to measure how much water you have in your tank. When the water level gets too low, mains water will trickle into the tank to top it up. 

In the Laundry

You can save a large amount of water by connecting your washing machine to your tank.

Washing machines can use in excess of 150 litres of water per load and most households do 5 to 6 loads per week. Using a 4.5 Star water efficient washing machine with 7kg capacity will cut back water consumption to 60 litres per wash and reduce the rate of depletion of your rainwater tank.