Grey
Water
This is a very basic break down of some grey water issues.
There could be serious health issues created for Australians
if the re-use of grey water is taken too lightly. Soil structure,
run-off and potential cross connections, need to be addressed
when considering grey water re-use. Across Australia the re-use
of grey water is being taken seriously and responsible authorities
such as the EPA are reconsidering their guidelines. As more
information becomes available we will update this page and
keep you informed.
For a more detailed preview, and links to more specific sites,
please see the Links & Extracts section of this page.
Products
to aid in the re-use of Greywater.
Waste water from non-toilet plumbing systems such as hand
basins, washing machines, showers and baths is known as 'grey
water'.
Grey water
needs to be used carefully. If it's not used properly, it
can make the householders ill and kill the plants you are
trying to care for.
Do not
store grey water for more than 24 hours
Never use 'black water'
'Black water' is water that has come in contact with toilet
wastes. Black water has to be chemically treated and disinfected
before it can be re-used
Grey water Dos
• Only use wastewater from baths, showers, hand basins
and washing machines (preferably the final rinse water)
• Only use grey water on the garden and rotate which
areas you water.
• Only apply enough water that the soil can absorb
• Wash your hands following watering with grey water
• Stop using grey water during wet periods
• Stop using grey water if odours are generated and
plants do not appear to be healthy
• Grey water that can be reused straight away without
the need for pre-treatment includes grey water from the shower,
bath and laundry rinse cycle.
• Choose phosphate-free or low-phosphate household cleaners
and detergents.
• Install a lint filter in your washing machine.
Grey water Don'ts
• Water vegetable gardens if the crop is to be eaten
raw or uncooked
• Use grey water that has faecal contamination, for
example wastewater used to wash nappies
• Use kitchen wastewater (including dishwashers) due
to the high concentration of food wastes and chemicals that
are not readily broken down by soil organisms
• Store grey water for more than 24 hours
• Let children or pets drink or play with grey water
• Allow grey water to flow from your property or enter
stormwater systems
• Don't use grey water if any member of your family
is suffering from gastroenteritis.
• Don't irrigate your garden with grey water in wet
weather, or if the soil is already sodden.
• Don't allow grey water to form pools or ponds in your
garden. The microbes will thrive, creating an offensive stink
and a health hazard.
• Don't allow your pets to drink grey water.
• Keep children away from garden areas irrigated with
grey water.
• Make sure your swimming pool and any other water features,
like ponds and birdbaths, are safe from grey water runoff.
• Encourage all the family to wash their hands before
eating.
• Don't urinate in the shower or bath.
• Never use water that has come in contact with the
toilet, or any other toileting fixture such as a bidet or
urinal.
• Don't reuse the water when you wash domestic pets,
because of the high level of bacterial contamination
Links &
extracts about Grey Water
How
Much Greywater Do We Create Each Day?
From
http://www.rosneath.com.au/ipc6/ch08/marshall/
An average urban Australian house uses 820 litres of water
per day for indoor and outdoor use. This encompasses toilet
(140 L), greywater (340 L) and outdoor (340 L) use. Toilet
water use is reducing as dual flush toilets become more widespread.
Greywater is generated in the bathroom (180 L), laundry (110
L) and kitchen (55 L). Each house varies from these averages
depending on appliances and habits, but the volumes indicate
a lot of greywater is generated that generally disappears
down the plug-hole never to be seen or re-used again.
The
Dos and Don'ts of Grey water Reuse
Extracts taken from :
http://www.epa.vic.gov.au/Water/Programs/reuse.asp
Greywater can be reused following a few simple steps with
readily available systems.
Greywater should only be reused when following the basic safety
tips outlined below.
A number of products are now on the market that enable access
to greywater from domestic plumbing situations. These products
are designed for immediate greywater reuse.
Greywater (all non-toilet household wastewater) can be a good
water resource in dry periods but its reuse can carry health
and environmental risks.
EPA supports water conservation methods and believes that
greywater can be reused effectively and safely in domestic
situations by following a few simple tips.
If you wish to put in a permanent system for greywater reuse,
further information can be obtained from EPA’s information
bulletin - Domestic Wastewater Management Series, Reuse Options
for Household Wastewater, Publication 812 (Adobe PDF format,
291 KB).
You should also talk with your local council regarding requirements.
Common
contaminants in grey water
Extracted from :
http://www.betterhealth.vic.gov.au/bhcv2/bhcarticles.nsf/pages/Grey_water_-_recycling_water_at_home?open
If it is not used properly, grey water can make the householders
ill and kill off the plants you are trying to care for. Some
of the common contaminants in grey water include:
• Salts
• Food materials
• Household detergents, soaps and chemicals
• Bacteria and other disease-causing microbes.
Health risk comparison
The health risks to you and your family depend on how you
use grey water. Examples include:
• Laundry rinse water is low risk, while grey water
from the kitchen is high risk.
• Sub-surface irrigation pipes are low risk, while hosing
the garden with grey water is high risk.
• Using grey water on ornamental plants is low risk,
while using it on vegetable gardens is high risk.
Grey water irrigation system
The various issues to consider before installing grey water
irrigation include:
• Council regulations - consult with your local council
about the rules on grey water use in your area. Many councils
won't let you use grey water - especially without an approved
treatment system. Some of the issues that may affect your
council's policy on the use of grey water include: the condition
of soil in your area, the slope of your block, how close the
subsurface or surface water is, and whether you are in (or
close to) a conservation area.
• Expertise may be needed - don't set up an irrigation
system yourself, unless you are licensed to do so. Consult
with a licensed plumber. Household plumbing must comply with
the Australian Standards AS 3500 and AS 1345.
• Use 'low risk' grey water - your irrigation system
should divert grey water from low risk sources, such as the
laundry rinse cycle, bath and shower.
• Keep it in your yard - your grey water should not
leave the boundaries of your property. It should not be allowed
to discharge into any (piped or surface) drainage system.
• Keep it out of the storm water - your grey water should
not leak into the storm water system. Make sure your pipes
don't discharge near any underground agricultural pipes.
• Avoid overwatering - check how moist your soil is
and spread the water around; don't just water in the same
place.
• Check for blockages - the contaminants in grey water,
like grease and slime, can easily block pipes. A filter may
help to avoid this problem.
• Store only for a short time - don't store grey water
for any longer than 24 hours, as microbes will thrive. Your
surge tank shouldn't exceed 80 litres. Make sure you have
an overflow drain connected to your surge tank that directs
excess grey water straight to the sewer. You may want to get
advice from a plumber on installing a settling tank to capture
grease.
Practical suggestions for safe garden use
Suggestions include:
• Filter your grey water before it reaches your garden,
to reduce the amounts of solids. Otherwise, your plants will
suffer from clogged soil.
• Ingredients in cleaners and detergents that can harm
or kill plants include total salts, sodium, chloride and boron.
Check product labels carefully.
• Evidence suggests that microbes from grey water have
higher survival rates on the topsoil. All irrigation should
be located sub-soil. Never hose, spray or mist grey water.
• You may need to reduce the amount of fertiliser you
use (note that native plants don't like nutrients - plant
selection could be critical for nutrients and soil moisture
levels). Consult with your local nursery for further information.
• Regularly water your garden with fresh water to help
prevent the build-up of salts in your soil.
Reduce health risks
What
are the Environmental Benefits of Water Recycling?
From
http://www.epa.gov/region9/water/recycling/index.html
In addition to providing a dependable, locally-controlled
water supply, water recycling provides tremendous environmental
benefits. By providing an additional source of water, water
recycling can help us find ways to decrease the diversion
of water from sensitive ecosystems. Other benefits include
decreasing wastewater discharges and reducing and preventing
pollution. Recycled water can also be used to create or enhance
wetlands and riparian habitats.
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