Questions and Answers on Grey Water
What is grey water?
Waste water from the bath, wash basins, washing machine and shower.
What is excluded?
Waste water from the kitchen sink (including the dishwasher) and toilets.
What is Grey Water diversion?
Usually this is untreated grey water and it cannot be stored for more than 24 hours and usually reused for sub-surface and surface irrigation.
Why should I treat the grey water?
Treating and sanitising grey water to a certain standard, allows the homeowner to store the water for discretionary use. It is safer water and less likely to cause disease or infections. This reuse depends upon the regulations in your area. Please check with your local health department or council. In Canberra ACT the treated and sanitised water can be reused for reuse in the laundry, toilet flushing, car washing and spray, surface or subsurface irrigation.
Is a grey water treatment system right for you?
Grey water treatment and sanitisation provides a constant source of reusable water for a wider range of purposes. Another popular alternative is a rain water tank however the amount of water from rain depends upon the local rainfall and your storage capacity. Grey water storage tanks can be much smaller provided the stored water is regularly used.
Can I over water my block?
Yes, with grey water it is possible to put too much water out for irrigation especially during winter when there is limited call for irrigation. In these circumstances the grey water storage can overflow to the sewer.
Should I use different soaps and detergents?
Use detergents that are low in phosphates, nitrates and salts. Further details
Do I need to chamois my car and house windows after washing?
Yes, dry the vehicle and glass of any source water that is not distilled water
Is there a pay back period?
No, water is not priced based upon its scarcity and therefore the cash savings from the amount of water saved will not repay your outlay. You may consider any additional resale value of the home, the betterment and enjoyment of the garden including the longevity of the plants. Dry soils may also cause house foundations to move hence increasing maintenance costs.
What steps do I need to take?
Please determine:
- Is your house built on a slab - retrofitting is difficult however plumbing for new homes cater for grey water reuse
- Are the grey water and black/sewer water drain pipes separated
- Are the drain pipes accessible for the purpose of separation - suspended floor and reasonable access under the houseDo you have drainage plans for the house - assists in the feasibility assessment and accurate quoting of prices
- Is there an appropriate location to install a sump or other method for the water to be harvested
- Is there an appropriate place to install a processor and storage tank
- Can the storage tank be above or below ground
- Tank size may be between 2,000 and 5,000 liters depending upon your needs and the grey water available. What shape or style of tank will you require
- Is there any local government or Federal government rebates available and what must be done to qualify
- How will my neighbours react; will you need to place a recycled water sign in the front yard
- Are you aware that purple hoses and signages are required on recycled water taps
- Can the storage tank, processor and sump be positioned so as to allow overflow to sewer
- What obligations are there upon you to maintain the system
- What happens if you sell the home and the new owner does not wish to maintain the system
- Can you use my existing rain water tank as the storage and re-use tank
- Do you want the reuse water for the garden, toilet and/or laundry
- How often does the system need to be serviced and what are the costs.
- What are the consumables, likely replacement cycle and costs
- Power consumption details
- Who will service the system and do I need to sign a contract
- What regulations are in place for these types of systems
- Are you entitled to any rates rebate
- Will plans need to be submitted for approval
- What are the warranty details