You can use untreated greywater to water your garden and lawn. To do this:
- use a bucket to collect water from your shower or washing machine
- connect a greywater hose to your washing machine water outlet and place the other end of the hose outside.
Greywater
Learn how to safely reuse greywater in your home. Check if you need approval to install a greywater treatment system.
What is greywater?
Greywater is wastewater from the bath, shower, basin, laundry tub and washing machine. It can be used on lawns, gardens and for other purposes around the home.
Greywater doesn’t include blackwater (wastewater from toilets and urinals) or kitchens, including in-sink disposal units.
Benefits of using greywater
The safe reuse of greywater helps to:
- lower your water usage and bills
- provide a water source for your garden and lawn in times of drought and water restrictions
- reduce the amount of water entering the wastewater treatment plant.
Ways to use greywater
Treated and untreated greywater can be used differently around the home.
Treatment systems are more complex and may collect, clean, store and disinfect greywater.
Treated greywater can be used to:
- irrigate your lawn and garden
- supply flushing water for your toilet
- wash paths, walls and vehicles
- support laundry to landscape systems (cold water source only).
In all cases, it's important to ensure that over-watering does not lead to run-off or ponding. This can cause a health issue for you or your neighbours.
Types of greywater systems
You can choose from 2 main greywater systems.
- Manual or automatic diversion devices.
- Treatment systems. These are more complex and allow you to use treated greywater in the washing machine, toilet and garden.
All diversion and treatment devices installed must meet legal requirements. Look for products carrying a watermark product certification.
Learn more about installing greywater systems on the Business Queensland website.
You can bucket your greywater or connect a greywater hose to your washing machine outlet without Council approval. The hose needs to be placed downhill within your property, ensuring there is no run-off from the desired garden or lawn onto your neighbour’s lawn or into a swimming pool.
If a premises generates up to 3 kilolitres of greywater per day, the work is classified as notifiable work. This means a licensed plumber can install the system without approval but will need to submit a Form 4 - Notifiable Work to the Queensland Building and Construction Commission.
If the premises generates more than 3 kilolitres of greywater per day, a Council permit will be required before work can begin.
Check your property’s suitability
Before you install a greywater system, you must check your property is suitable for greywater irrigation. Suitability depends on various land aspects and whether your property can cope with the volume of greywater generated by your household.
The Queensland Plumbing and Wastewater (QPW) Code sets out the suitability criteria and requirements for greywater installations. Contact a licensed plumber to find out which option is best for you.
Use the following step-by-step process to estimate your household’s weekly volume of greywater.
You also need to check that your property can cope with the volume of greywater generated by your household.
Calculate the area available for irrigation
Measure the size of the garden or lawn area where you will use the greywater. Don’t include space covered by buildings or hard surfaces (e.g. driveways). Leave appropriate setbacks from buildings and boundaries.
For setback distances, refer to the QPW Code.
Calculate the volume of greywater that your household will generate
Use this formula: Number of people per household x total daily use (litres/per person/per day) x 7 days = greywater volume per week in litres.
Calculate the area needed to soak up this volume of greywater
This depends on the soil type and is based on Brisbane's average Design Irrigation Rate (DIR) of 25 mm/week.
Area needed (square metres) = volume (litres/week) ÷ 25 (DIR).
Compare the area needed for greywater generated with the area available
The area available (step 1) should be larger than the area needed (step 3).
Where there isn’t enough land to distribute all the greywater from a house, it’s possible to divert the greywater from just one source, such as a laundry, or limit the diversion times.
Example calculation:
- Available area for irrigation = 130 square metres.
- In an average 4-person household: 4 people x 95 litres x 7 days = 2660 litres of greywater generated per week.
- Area needed to soak up the volume of greywater = 2,660 litres ÷ 25 (DIR) = 106 square metres.
Complete the form
Prepare your documents
Prepare a site and soil report, and site plans showing the location and details of the proposed facility and the location of any buildings.
Lodge your application
Submit all documents via email to domapp@brisbane.qld.gov.au
After you apply
The Plumbing Services Group Assessment Team will contact you about your application within 10 working days and advise on permit fees.
Once you receive a permit, a licensed plumber can install the greywater system. They will need to arrange for Council to inspect the completed work.
Make sure you’re ready to comply with your permit conditions and compulsory greywater auditing.
Greywater monitoring
Council is required by law to monitor greywater systems. This ensures the systems are safe and comply with their approval conditions.
- If you own a greywater diversion device, the permit conditions will outline any ongoing monitoring and inspection requirements.
- If you own a greywater treatment system, the service agent must provide Council with a copy of the annual service report within 10 business days after servicing the facility.
Offences and penalties
All complaints that are lodged about greywater will be investigated. Our priority is to protect your health, wellbeing and the environment.
You may receive a fine if you:
- use an unapproved greywater system
- own a system that wasn’t installed by a licensed plumber
- undertake unapproved plumbing work
- let greywater pond, cause an odour or run off your property.
You can use both treated and untreated greywater to water plants, lawns and gardens. To ensure water quality isn’t compromised, untreated greywater shouldn’t be stored for longer than 24 hours.
Dispose of greywater at a dedicated greywater dump point. You should do this if you’ve stored greywater for more than 24 hours.
To find the nearest dump point, contact Urban Utilities on 13 26 57.
To find out more about the greywater application process, call Council's Plumbing Services Group on 07 3403 8888.
No, you can’t use wastewater from toilets or kitchens as untreated greywater. This wastewater is more polluted than greywater and reuse is not permitted.
Greywater treatment systems vary in price. Depending on the complexity of the system and the intended use of the greywater, a simple diverter can cost under $1,000. Complete treatment systems can cost several thousand dollars and water quality varies accordingly. The best option for you will depend on the amount of greywater you produce and your budget.