|
Clothes washing accounts for 10-30% of the average household's water use.
Grey water from the laundry can be used and, with the right choice of laundry products contamination can be reduced to an acceptable level. It is advisable not to use greywater continuously on the garden.
Laundry products: what to look for
Many chemicals go into modern laundry products in the push for sterile, whiter than white clothes and linen. Plants, beneficial insects and soil microbes are sensitive to certain chemicals, so it's important to use an environmentally responsible laundry powder if you are planning to reuse laundry water on the garden.
When choosing a laundry powder, avoid those containing antibacterial agents, phosphates and extras such as optical brighteners, enzymes, synthetic fragrance and bleach.
Instead, look for laundry products that:
- Laundry liquids tend to be more concentrated and contain less bulking ingredients
- Are phosphate-free (phosphates can harm sensitive native plants)
- Are low in sodium (salt) as this can damage your garden
- State that all of their ingredients are readily biodegradable (the Australian Standard for laundry powder biodegradability only requires the surfactant to be biodegradable)
- Are concentrated (cheaperpowders can contain extra salt as a bulking ingredient)
- Can be used in cold water (hot water can damage plants and soil)
Go to
For information about laundry products that are safe to use if you are using your greywater for watering your garden
Tips for 'garden safe' laundry greywater
- Regulations require that you keepall grey water within your property. It must not run into neighbouring properties or drains.
- Untreated greywater must be delivered a minimum of 100mm below the surface of the soil (sub soil irrigation)
- Current guidelines for the bucketing of greywater allow the water to be poured directly onto the ground but to reduce health risks, don't allow greywater to pool on the surface of the ground.
- Avoid water pooling on the surface as children may play with grey water and pets may drink the water.
- Don't use the greywater from washing nappies on the garden.
- Health authorities advise against using greywater on plants and vegetables that you intend to eat.
- Greywater may be used to water fruit trees but greywater must not come into contact with the leaves or fruit.
- Don't use hot laundry water directly from the machine onto your garden.
- Do not store grey water for more than 24 hours unless it has been treated by an approved Greywater Treatment System installed by a licensed plumber
Greywater: The Basics
Greywater, the 'waste' water from the laundry and bathroom, is now seen as a resource - water that can be reused, reducing our demand for potable water. However, greywater can carry higher levels of pathogens and residual chemicals and shouldn't be used unadvisedly.
Kitchen waste water is not recommended for reuse as it tends to contain high levels of fats, food residue and other contaminants.
Bathroom grey water is sometimes used on gardens provided it is not heavily tainted with soap, bubble bath and other toiletries. However, bathroom plumbing can be difficult to access in order to set up greywater diversion systems. All such plumbing work must be undertaken by a licensed plumber.
Laundry water is most commonly reused on gardens. Raised laundry sinks make pipes accessible and allow gravity to help the water flow into the garden. The use of eco-friendly laundry products reduces the chemical content of the greywater lowering the impact on the soil and plants.
Grey water systems
There are many methods for reusing grey water, from simple bucketing to complex treatment and recycling systems.
Factors that can influence your choice of grey water reuse method include:
- Budget - Costs range from simple relatively inexpensive diverters to complex treatment, storage and irrigation systems that cost several thousand dollars.
- Existing plumbing - The accessibility of the pipes that carry grey water from inside your home may affect your options.
- Existing garden landscape - The installation of irrigation systems may disturb existing plants or soil. Your garden design and choice of plants will also determine your garden watering needs.
- The elevation of garden bedscompared with grey water sources -This will partly determine if the force of gravity alone is enough to push the grey water through the system to where it is needed. Some sloping blocks are well suited to gravity fed grey water diversion systems, while systems that recycle grey water with raised garden beds may require a pump.
Types of grey water system
The various methods of grey water reuse fall into two categories: diversion systems and treatment systems.
Diversions systems typically direct grey water from the laundry or bathroom to the garden for immediate use, without making changes to its quality.
Treatment systems improve the quality of the wastewater by filtering, disinfecting and other treatments. Treated water can be stored for longer periods without the risk of it going septic.
Components
Grey water systems can have a combination of various components, as outlined below:
- Diverter - A diverter is a fundamental component; a device connected to waste water pipes that can switch the flow of water away from the sewer and direct it elsewhere.
- Overflow device - Many systems also include an overflow pipe or device that directs grey water to the sewer in the event of the system becoming overloaded or not functioning properly.
- Filter – Grey water can contain soap scum, lint, hair, bits of sand and dirt and other small debris, all of which can block drippers or porous hoses, so it is useful to have some sort of filter connected to the diverter or elsewhere in the system.
- Simple distribution pipe or hose -Water can be diverted into a pipe or hose and applied directly to parts of the garden. This effectively floods areas of the garden, if only temporarily, increasing the risk of the water running off the property. This concentrated application of the grey water to the ground can lead to a build up of chemical residues in the soil.
- Pump-A pump may be needed to push greywater through a distribution system when gravity alone is inadequate to do the job.
- Distribution system - It is generally safer, more convenient and more effective to direct grey water directly to the soil through distribution or irrigation systems.
- Drip lines - Untreated greywater must be delivered by a sub soil irrigation system.
Choosing and installing a system
Greywater use is a way to reduce your demands for fresh drinking quality water and, used on the garden, a way to keep your plants thriving during times of drought and water restrictions. Grey water used without forethought can be a health risk.
For this reason, only permanent greywater systems approved by the Department of Health can be installed. Changes to any plumbing systems must only be made by a licensed plumber to eliminate the risk of backflow and crossconnection problems that arise when undertaken by unqualified people. Water authorities and licensed plumbers specialising in grey water systems can provide advice on the right system for your particular situation. You can find a specialist plumber in your area through eco-smart plumber.
Your licensed plumber can advise on the cost and greywater systems approved in your state.
Treated greywater systems currently can cost anywhere from $9,000.00 to as much as $15,000.00. As demand rises and competition increases, costs will become lower, but because any Treatment system must filter and disinfect, they will remain a relatively expensive option.
Applying for Greywater Reuse
Please click here for full information and application forms.
|
