ely
Member
Hi all,
Any tips on pipes etc we can use for subsurface greywater irrigation?
Something that doesn't block up with roots. One local plumbing shop reckons there's no such thing and recommended greywater sprinklers. But we have small kids and the greywater is untreated so I don't want to do that.
Any other suggestions?
Michelle
Geno
Member
We have a sandy type of soil with no clay base which means any subsoil drainage tends to dissappear without getting to the roots. What we have used is the standard purple drip line on the top of the garden soil and covered with a thick layer of wood mulch. It doesn't clog and so far roots haven't been a problem but it has only been in a couple of years. Other than sprays it has been the most effective method we have used. We still use sprays but these are fed from tank water, the grey stuff only through the drip lines. I'm not suggesting this as a perfect solution but it works for us.
ely,
You were wise to dismiss the advice of "one local plumbing shop" to use greywater sprinklers, 'advice' that is contrary to health regulations in most areas. I did a quick search on Qld regulations but could not find anything specific for such grey water usage, just a lot of outdated advice by the QLD Water Commission and other bodies that should be removed from the web. Have you tried the local nursery for advice?
The only grey water I would use is the final rinse from the washing machine and many plants including grevillea, bougainvillea, azaleas and rhododendron, herbs and citrus fare poorly on a grey water diet. Vegetables should also not be watered with grey water. There are many well researched articles now available that detail the long term effect grey water use has on plants, soil structure and beneficial soil organisms.
One product my company tested a few years ago was the Leeaky Hose:
http://www.leeakyhose.com.au/index.php
We found this product was resistant to root invasion and operated with a very low pressure requirement. We had no interest to also test this product with grey water but grey water is addressed in detail in one of their downloads:
http://www.leeakyhose.com.au/pdf/LHmanual.pdf
dymonite69
Member
Queensland govt regs:
http://www.dip.qld.gov.au/sustainable-housing/greywater.html
http://www.derm.qld.gov.au/waterwise/gardening/pdf/domestic_greywater_qld.pdf
Ely,
I am also in the process of selecting wastewater systems (for my new house in Brisbane). The Eco Design greywater system (http://www.greywater.com.au/greywater.html) (Qld approval at http://www.dip.qld.gov.au/plumbing/greywater-treatment-plants.html) uses large 75cm? diameter solid plastic pipe to feed greywater to small plastic "pits" - maybe 15-20 litres? which then leak it out to the garden via subsurface irrigation. The "pits" have access hatches so they can be maintained (any roots removed etc) once a year. Business located in Brisbane.
Latest Qld Plumbing/Wastewater laws are at http://www.dip.qld.gov.au/plumbing/plumbing-laws.html
onrbikes
Member
I've been using my greywater system for over 10 years with no problems.
All of the waste water (no Black water) goes to a large soak well for settling. 2 exit pipes are located below the entry pipe on the opposite side.
One goes to another small holding tank that acts as an overflow and is surrounded by rocks.
The other pipe goes to an orange tree, 2 date palms and 2 pomegranite trees via a large drain pipe that has many 12mm drilled holes. The pipe sits in crushed rock and is covered with shade cloth and more crushed rock. This allows clean water to seep through the pipes and water the roots.
It works for me.
onrbikes,
Does your kitchen greywater go into your system? If so do you have some sort of greasetrap before the distribution system?
PS my previous post referred to 75cm (I meant 75mm) plastic pipe as part of the Eco design greywater system. I checked the specs and it is 100mm sewer pipe that carries the irrigation water to the "pits"
P.S. The reason the link (above) to the system approval in Qld doesn't work is that it includes a parenthesis. Try this http://www.dip.qld.gov.au/plumbing/greywater-treatment-plants.html
Hi Michelle, good on you for seeking advice on the sprinkler issue! I wouldn't want my kids playing in the backyard if I'd been using sprinklers to get rid of our greywater.
We manufacture a subsurface textile irrigation system that was designed specifically for use underground. It's called KISSS Subsurface Textile Irrigation and is a more advanced version of drip irrigation. We work with a lot of people using KISSS to disperse their household greywater in their backyards.
With KISSS the water is carried out into the soil via a geotextile surrounding the irrigation pipe. This means that the water is absorbed at a rate dictated by the soil - not by the flow of the water from the pipe. It has lots of benefits for irrigation, but for dispersel the biggest benefit is that you won't get water tunnelling to the surface (which can sometimes happen with bare drip)
As for root intrusion, you'll find the only way drip pipe guarantees against root intrusion is with the addition of a chemical or herbicide. Because of the design of KISSS we don't need to rely on harsh herbicides to deter roots. We have a root intrusion statement on this page of website http://www.kisss.com.au/page/iwt_library.html (scroll down to the bottom).
Hope that helps.
Best of luck.
Bianca
Marketing Manager
IWT
ely
Member
Hi Bianca,
Your product looks interesting, I didn't see when it was on the New Inventors.
Could you give me a ballpark figure as to how much it costs and how much area you would recommend it cover for around 2500L a week greywater?
Also, your website says you need to flush the system every 6 months - how do you do that?
If I have more Q's can I call head office or do you not deal with residential people directly?
I have been considering bypassing my greywater tank and feeding it into a reedbed system, which would then clean up the water before it enters our dam. But then I'd have to pump to water our yard and garden.
Subsurface would be great if I knew it would not clog up.
Ely
dymonite69
Member
The Biolytix system uses KISSS for their irrigation system.
The main problem is that all wastewater irrigation system are at risk of biofilm formation and blockage. This results from the organic molecules that are still in the water even after processing. KISSS has a biocide, Vinizene released in low doses in the system to reduce this. Apparently it is not significant enough to have environmental effects.
Biolytix recommends scouring the lines if they do get blocked with chlorine (e.g. issues with chlorinated hydrocarbons - a potential carcinogen) or copper sulphate.
I found one published article comparing its performance:
CLOGGING INCIDENCE OF DRIP IRRIGATION EMITTERS DISTRIBUTING EFFLUENTS OF DIFFERING LEVELS OF TREATMENT
