On this page:

As our population grows and our climate becomes drier and more variable, we need to make the most of all sources of water to ensure secure and sustainable water supplies are available into the future.

Using water more efficiently is important. But this alone will not meet future water demand. Using more diverse water sources like rainwater from your roof, stormwater and recycled water will help meet water needs that currently rely on river water and groundwater.

They provide a range of benefits to our community, including:

  • saving drinking water
  • protecting our waterways and bays by reducing the amount of stormwater and treated wastewater that enters them
  • returning water to Traditional Owners and the environment
  • retaining moisture in our urban landscapes for cooler, greener cities and towns.

When considering diverse water supplies, you should choose the most appropriate water source for where and what it will be used for.

You can find information and guidance from the EPA on how you can safely use these sources.

Recycled water

Recycled water is produced from wastewater from homes, businesses or industries that is treated at a wastewater treatment plant to a standard that is suitable for its intended use.

Once treated, the recycled water is delivered by water corporations to their customers through a separate (purple) pipe system.

A qualified plumber undertakes the plumbing of recycled water services to ensure that they are plumbed correctly.

Treated wastewater and recycled water that is not reused is released to waterways, bays and the ocean under EPA permissions.

Using recycled water

In Victoria, recycled water has been used safely for non-drinking purposes for decades. This includes uses such as:

  • agriculture (for irrigation of crops and stock drinking water)
  • irrigation of sporting fields and parks for residential and commercial purposes (via purple pipe schemes) or industrial processes
  • supporting biodiversity (for example, the Ramsar wetlands at the Western Treatment Plant
  • water treatment processes.

In other states and around the world, recycled water can be further treated and added to drinking water supplies.

Recycled water supplies are largely independent of rainfall, making them a more reliable source in an uncertain climate.

Although the volumes of wastewater produced are large and continue to grow, only a small amount is currently reused. There are many reasons for this, and DEECA is committed to working with the water industry to increase recycled water use where it is fit for purpose.

If you are a home or business with a purple pipe, ensuring your system is connected to your laundry, toilets and garden means that you can save precious drinking water, reduce your water bills, and help return water to our rivers.

Your local water corporation's website has information if you want to learn more about recycled water and how it is treated and used.

Investigating barriers to using recycled water

DEECA has been working with the water industry, EPA and the Department of Health to address some of the barriers that are making it difficult to use recycled water.

Projects include:

Investigation into the impacts of pricing on recycled water uptake fundings summary

Mandating recycled water use investigation findings summary

Stormwater

Stormwater is water runoff from urban areas. This water is different from runoff in undeveloped areas, because of all the hard surfaces in cities and towns, such as roofs and roads. Stormwater runoff carries pollution into waterways, disrupts natural flows and causes erosion.

This happens as our drainage systems are normally designed to carry stormwater away as quickly as possible, to reduce local flooding.

Using water sensitive urban design (WSUD) in cities and towns can reduce the damage that stormwater does to the environment. WSUD uses better urban planning and design to mimic the natural water cycle and capture stormwater for reuse. More information on WSUD is available from Melbourne Water.

Many new developments are required to treat stormwater to prevent pollution, for further information on those requirements visit stormwater management for urban development.

Stormwater that is captured can be treated and reused for non-drinking purposes. Reusing stormwater helps to protect urban waterways and reduce how much drinking water we use. Currently, in Victoria, stormwater is often used for irrigating local parks and open spaces. But there are many other things it could be used for, such as:

  • crop irrigation and other agriculture
  • residential and commercial purposes (via purple pipe schemes) or industrial processes to environmental benefit (where there isn’t enough river water for flows).

DEECA is working with the water industry to improve stormwater management in Victoria. Visit improving stormwater management for more information.

Rainwater

Rainwater is water that is captured from your roof, before it touches the ground or other hard surfaces. When it touches the ground or other hard surfaces it becomes stormwater.

Rainwater is normally much cleaner than stormwater, as a home roof is generally much cleaner than other hard surfaces, such as roads and driveways.

You can capture and reuse water from your roof using a rainwater tank. This is one of the easiest ways to save water at home and keep your garden green. It can also lower your bills and save drinking water. In urban areas, rainwater is typically used for:

  • watering your garden/lawn
  • flushing toilets
  • clothes washing (connection to your washing machine).

If your rainwater tank is properly installed and maintained, you could save up to 30% on your water bill.

Using rainwater can also help to:

  • reduce our use of river water and desalinated water
  • protect our rivers from stormwater pollution
  • reduce operating costs of drinking water infrastructure
  • reduce local flooding.

Before you buy or install a rainwater tank you should think about:

  • choosing the right tank for your needs
  • understanding maintenance requirements
  • ensuring safety and water quality
  • what permits you might need
  • any regulations and Australian standards you need to follow.

Learn more about installing and maintaining your rainwater tank.

Greywater

Greywater is wastewater from domestic use in the home. It is water from baths, showers, hand basins and washing machines (the final-rinse water is best).

Greywater from the kitchen (including dishwashers) should not be used. The concentration of food wastes and chemicals are not broken down by soil organisms.

Using greywater can keep your garden thriving during low rainfall periods. Yet, you need to know how this affects your home, garden and environment. If used incorrectly, greywater can damage your soil, plants or even put your family and pets at risk. This is because greywater has chemicals and bacteria in it, that with the wrong application can cause problems.

You don't need permission to divert greywater from the shower and washing machine for immediate use on the garden. But if you want a permanent greywater treatment and reuse system you need to have an EPA-approved system and a local council permit.

More information

Environment Protection Authority (EPA) or contact your local council.

Page last updated: 23/10/23