Rainwater tanks

Rainwater is considered a high-quality water source with a lower contamination risk than surface water.

However, this doesn't guarantee safety and contamination is not always visible.

Installing or using a rainwater tank

You can use rainwater tanks to collect and use water as a private supply anywhere in the Territory.

You don't need approval to install or use a rainwater tank, but you should make sure the water is safe to drink.

Before you install a rainwater tank, make sure it has:

Once installed, you must regularly maintain it.

You can get guidance about the use of rainwater tanks on the Australian Government's Department of Health website.

If you have a commercial or community facility that uses a rainwater tank, find out how to manage private water supplies.

To avoid or minimise water quality problems you can do the following:

Regularly clean the roof and gutters collecting rainwater by removing leaves, bird droppings and other organic matter.
After the dry season or when you clean the roof and gutters, divert water from the first rainfall using a first flush or bypass device. This reduces the amount of contaminants entering the tank.
Remove overhanging tree branches that may drop leaves into gutters.
Paint or remove any lead flashings used in the roof construction.
Install screens on tank inlets and overflows to prevent leaves and small animals from entering. Check the screens regularly.
Examine tanks for build-up of sediments every 2 to 3 years or if sediments are seen in the water flow. Any sediment build-up needs to be removed (desludged).
Regularly inspect in-ground tanks to ensure they don't become contaminated. Water that has flowed over or through the surrounding soil or ponded on the lid must not be allowed to enter the tank.
Any nearby onsite wastewater management systems (OWMS) must be maintained and working effectively. OWMS effluent must not be allowed to enter drinking water tanks.
If the water supply has not been used for 24 hours or more, and water has been stagnant in pipes, copper or lead can build up. You should flush the pipes for a few minutes until fresh water flows through from the tank.

Tanks built from different materials need to be treated differently during maintenance:

Plastic tanks need to be anchored when empty.
Concrete tanks should not be allowed to dry out in case of cracking.
Tanks with a ‘cone scour’ base are easily cleaned by opening the cleaning outlet to allow the water to drain out with the sludge, then rinsing with a hose.
Small, flat-bottomed tanks can be drained, rinsed with a hose, and tilted to drain.
In-ground tanks need to be cleaned and refilled quickly in case of tank displacement from the ground.

Below are the recommended maintenance schedule.

You should check for all of the following every 3 months:

You should check the following annually:

You should clean the roof and gutters every 3 months.

You should also do the following annually: