Grey Water System

Posted by on Oct 21, 2007 in Life Support Systems | 4 Comments

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It took as a little while to find out where the grey water from the house went when we first arrived.

Eventually we traced it to a pipe that was buried 10cm underground near the roots of our pomegranate tree. At the time this was just water from the sink. Like this is stayed for over a year.

We planted pumpkins around it, a passionfruit popped up but it was pretty low-tech.




Feb 2007


One of our first new owner-builder without a clue moments was getting a bath installed.

This meant fitting a tub in somewhere getting water as close as possible (at this stage still cold Webster's creek water) and then having somewhere for it to go.

While we were setting up a bathroom – we also setup a twin tub for washing clothes.

We stuck with the homes original concept of pipe out onto the ground below to runoff for simplicities sake. From legality alone this was never going to do for the long term.





Feb 07


When I first introduced Jerem from the Permaforest Trust around my share a seed was planted to sort out the grey water situation.


We discussed the design brief over email.


Our soils are like beach sand. The initial idea was to line the terraced beds with clay so that the water would run through some water loving plants that would catch the bits. This would eventually lead into a banana circle.


This was later amended to a simpler three tier design after the scope of the project day was also expended to float the slab on the composting toilet.




April 2007


So the big day arrived, it was also unfortunately pouring with rain. Jack managed the project with help from others. He dug out three beds and used a recently felled dead Mexican tree fern to hold them level.



Jack lays pipe – April 2007


We cut the original pipe just under the house and installed a small grease trap. This is required by council law – there are good reasons to have it and good reasons not to. For our situation the main reason is that large chunks of food that might go down the kitchen sink could block the tiny holes that are drilled into the pvc distribution pipe. The main downside of trap is that it effectively forms an anaerobic environment – that's the stinky way to break down organic matter. Unless s or p traps are used under all the sink holes – swamp gas rises from the pit and is piped right into the home!


I've been exposed to all manner of organic breakdown since I moved onto Avalon – and I'm fairly used to the worst of it. However it doesn't really reflect well on my shining example of ecological living when guests visit and are greeted by a foul sewerage stench.


The bath and shower water bypass the trap entirely as it is intended for kitchen chunks.




Once the holes were drilled ag pipe is then threaded over the top. This is to give the holes some chance of not being filled by greedy roots trying to get to the source and clogging up the works. The holes are drilled on the top of the pvc pipe so the pipe fills with water and then leaks out of all the holes at once.




Once the beds were all setup, A boundary of Vetiver and Lomandra grass was planted. These are intended to stop the invasive grasses from entering the main beds.


As the soil has been heavily disturbed we mulched as quickly as possible – this will prevent the weed seeds in the soil bank from germinating.




A job well done!


Shortly after we visited the trust and harvested some Taro and Arrowroot root stock. We planted that in and have effectively left it to work.




August 2007




September 2007




October 2007


Our recent inspection of the grease trap revealed;





October 2007






November 2007


  1. Charles Cone
    November 17, 2007

    Brac Greywater Recycling Systems

    The Brac Greywater Recyling System is available in the Atlanta region from Southern Energy Solutions, Marietta, Georgia, United States.

    The Brac Greywater Recycling System takes in greywater (bath/shower/laundry water), filters and treats it, then sends it on demand for toilet flushing. By reusing greywater for toilet flushing, the typical home can save 30% or more on potable water consumption.

    The Brac Systems are available in residential-use sizes 250/350/450 liters (66/92/119 gallons US) and commercial-use sizes 4200/5000/6600 liters (1110/1320/1745 gallons US).

    Southern Energy Solutions

  2. J Watson
    January 28, 2008

    I found a fantastic company called Waterwise Systems who fully installed their Greywater System for me!
    I cant believe how simple it is compared to so many other things i was looking at doing.
    All the water from my washing machine, shower and bath is slowly released into both my front and back gardens through underground drippers! I have had it for 6 months and my garden looks amazing! Plus i feel great about saving water..
    If anyone is interested go to their website

  3. Wholistic » Blog Archive » House Water System
    November 27, 2008

    […] Grey water is treated on site in a special bed of Arrowroot, Taro, Comfrey and Tansy. This system was designed and installed on a work activity day organised by the Permaforest Trust. The kitchen and the bath are run through a grease trap. The bath needs an S bend installed to prevent swampgas from coming back up the line. There is debate in the greywater sphere about the effectiveness of greasetraps as they encourage anaerobic decomposition, however they are still the legal standard. From the greasetrap water feeds into three separate beds built on terrace. The root crops are not to be eaten, but was can use them as rootstock for areas designed for food production. The system is currently thriving and experiencing a burst of spring life. Lomandra and Vetiva grasses have been planted to keep out invasive grasses. […]

  4. Water Garden Advisor
    October 27, 2009

    Interesting blog post. What would you say was the most common problem?