Recycling and reusing water at home with a greywater system

As we face the challenges of decreasing rainfall and a growing population, water conservation has become crucial more than ever. Reusing greywater can be a simple effective solution. By using it for irrigation, we can reduce our reliance on potable water sources and create healthier gardens.  

For example, in the Perth Hills, a greywater system was installed to an existing home, providing irrigation for a 100 sqm garden saving around 114,000 litres of water annually. That is equivalent to approximately 11,400 buckets of water. Additionally, this practice helps save energy and reduce greenhouse gas emissions, benefiting both our environment and communities.

Understanding greywater

Greywater is wastewater from baths, showers, spas, bathroom basins, washing machines and laundry tubs in your home. Greywater can be used to irrigate gardens and lawns, which can be very helpful during drier months.  When treated properly it can even be used for toilet flushing and laundry to reduce your overall water use in the home.   

When designing a greywater system to ensure even distribution of grey water, it’s important to consider  the following: 

• local climate – ensure the system can be turned off during rainy periods to prevent overwatering 
• type of soil – sandy soils are ideal for greywater use 
• garden layout – plan the layout to ensure even distribution of greywater.

Different types of greywater systems

Manual bucketing - collecting greywater manually using a bucket. This method is simple but labour-intensive.

Greywater Diversion Devices (GDD) - these systems divert water directly to your garden without storage or treatment. They can be gravity-fed or pumped. Learn more about greywater diversion system.

Greywater Treatment Systems (GTS) - these systems treat greywater directly to a higher standard, allowing it to be used for toilet flushing and laundry.

Just like any other system, regular maintenance of the greywater system is essential. This includes cleaning filters regularly to prevent clogging, ensuring pumps are functioning properly and not blocked and periodically flushing drip lines to remove any build-up of debris.

For detailed information on reusing domestic greywater, refer to our greywater guide.

Installing a greywater system

In WA, greywater reuse is regulated by the ‘Code of Practice for the Reuse of Greywater in Western Australia’ (Department of Health, 2010). It’s important to follow these guidelines to ensure safe and effective greywater reuse. This includes having the system installed by licensed professionals, using greywater below soil surface to prevent human contact and ensuring systems have an overflow to the sewer to handle excess greywater. Additionally, surface irrigation is permitted if the greywater has been adequately treated. 

For more information on installing a greywater system, visit Department of Health.