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Greywater
Using grey water can help ease the pressure on our water supplies; however, there are possible health and environmental issues that need to be considered and understood before using grey water in the home and garden.
What is Greywater?
Greywater is waste water from your kitchen, bathroom and laundry. Usually, this water goes to the sewer but some of it is clean enough to re-use in your home or garden.
What is Black Water?
Black water is water from the toilet and must be discharged to the sewer.
How Can I Use Greywater?
Greywater can be used to water gardens and lawns. Please note, greywater should not be used on fruit and vegetable plants that will be eaten raw. It can plumbed back into the house to flush the toilet. This must be done by a licensed plumber and permits may be required.
Is Greywater Safe?
Grey water contains a large number of bacteria, which could pose a risk to human health, pets and the environment. Treated grey water is safe for some household uses, provided it is collected and used appropriately.
Tips for Using Greywater
- Don't spray or hose grey water
- Use a below ground system to distribute the water to your garden such as a soaker system
- Alternate watering areas in the garden to avoid the build up of chemicals in one spot
- Regularly check that your irrigation pipes are not blocked. You may need a screen or filter to stop lint, hair and grease from clogging your pipes
- Untreated kitchen water should not be used because it can contain grease and detergents
- Take care when choosing detergents and other household cleaning products. Some shampoos, laundry detergents and cleaning products could cause damage to the garden as they may contain harmful chemicals like chlorine, sodium and phosphorous
- Check the labels carefully
- Water used to wash soiled nappies should be avoided at all costs
- Rinse water from the washing machine is the 'best quality' grey water
Should Greywater Be Treated?
Treating grey water means changing the biological, physical or chemical properties of the water. This can include filtration, storage, aeration or installing a mechanical treating process.
The Environment Protection Authority (EPA) must approve grey water treatment systems that are designed to treat up to 5,000 litres per day before council can issue a permit for installation.
There is no specific legislation banning the use of untreated grey water in Victoria but it is important to understand that untreated grey water may be associated with health risks. The Department of Human Services does not recommend the re-use of untreated grey water inside the home. Untreated grey water must not be stored for more than 24 hours as it has the potential to become septic.
Council Regulations
Keep grey water within the boundaries of your property and make sure that it doesn't enter the stormwater drains.
There is no specific legislation banning the use of untreated grey water in Victoria but it is important to understand that untreated grey water may pose risks to health. Untreated grey water must not be stored for more than 24 hours as it has the potential to become septic.
Council officers may investigate grey water that places public health at risk under the nuisance provisions of the Health Act 1958. The EPA may investigate grey water that causes environmental pollution under the Environment Protection Act 1970.
Please check with Council before installing a grey water system (see details below).
Who Can I Ask About Greywater?
- Your licensed plumber
- Council's Sustainability Unit on 9262 6363
- Council's Environmental Health Unit on 9262 6445
- Environment Protection Authority on 9695 2722