"Self-sufficiency does not mean 'going back' to the acceptance of a lower standard of living. On the contrary, it is the striving for a higher standard of living, for food that is organically grown and good, for the good life in pleasant surroundings... and for the satisfaction that comes from doing difficult and intricate jobs well and successfully." John Seymour ~ Self Sufficiency 2003

Wednesday, 28 November 2012

Grey water filter

You may, or may not, know that we are so off grid that we only have the supply of municipal water.  And, not the best water at that.  But, it is drinkable, so mustn't complain... :)  And that, together with our rain water tanks should stand us in good stead for our human requirements.

The ramifications though, are that our "waste water" is our responsibility.  The black water goes into a large septic tank, and, providing that I feed the tank with "good bacteria" every month, all should be well.

But we didn't want our grey water (water from our shower, bathroom basin and kitchen sink) unnecessarily filling our septic tank.

So, we have installed plumbing to take the grey water to a "pond" ( in inverted comma's as it's a work in progress...:)  )
The "pond" in the foreground - not such a pleasant
view or experience
Initially, with the chaos of builders, building, mess and confusion, the water just ran to the "pond".  But the "pond" wasn't looking so good - in fact it was not pleasing at all.  Distinctly unappealing even to the bird life.  A direct result of all the inevitable kitchen grease and minute scraps of food which were being flushed down the drain.  So I put on my thinking cap and came up with this solution...

The higher hole was inserted on the side of the
kitchen sink pipe, and the lower hole is for
the pipe to the pond 
I purchased a 20lt black box, drilled two holes - one in the top at the end for the "in pipe" and one in the lower end for the "out pipe.  Then the "in pipe" and the "out pipe" got siliconed in place and fitted to our kitchen waste pipes.
Vermin proof lid on the grey water
filter box
It comes with a secure lid, so that will also deter vermin.
Larger filter stones layer the base of
the black box
Then, with RMan's assistance, I placed a layer of larger stones in the base of the box.
Smaller filter stones were laid on top of
the larger stone
On top of that we placed a layer of smaller stones.
A couple of layers of shade cloth
to hold the sand
On top of the stone I lay some shade cloth...
A layer of clean sand
... and filled the shade cloth with sand.
Test run...
As the water enters the box from the kitchen basin in lands on the sand and it then has to filter down through the sand, and the two different layers of stone before exiting the box and continuing on it's merry way to the "pond". A couple of days later I inspected the set-up to ensure that it was working correctly.  What I found was tiny scraps of food covering the top of the sand layer.  With my fertile imagination I envisaged a thriving community of nastiness, including a nasty smelly result, developing within a short space of time.


I had another plan.  We all know that washing machines like to chew just one of a pair of socks.  And that one invariably has the odd-sock-out lingering in the hopes that it's mate will surface somewhere.
Leftover socks that the washing machine
didn't fancy...
I decided enough was enough - I mean we had schlepped these odd socks all the way from our town house, and I still couldn't find it's mate.  So, it was time to put those socks to another good use...
Yup - they were put to good use
as an additional filter
Fixing it on to the end of the inlet pipe, I now have all those scraps being caught in the sock, instead of landing on the sand in the box.  An extra filter so to speak.
It works a treat :)
Yeah, cleaning out the sock on a weekly basis entails shoving on a pair of rubber gloves, but hey, I brought two babies into this world, and a greasy slimy sock is nothing compared to what they delivered on the odd occasion in their first few months of life...LOL

But, most importantly, the water that is heading for the pond is clean (er), and it doesn't smell anymore, and that result is worth a couple of minutes every 7 - 10 days in order to complete the unpleasant task of cleaning the sock...
Clean water - it works :)
We have a saying in this country - "a Boer maak a plan" (a farmer makes a plan).  McGyver - eat your heart out - or should that be "Thanks McGyver - I did learn something from watching your programme all those years ago..." :)
The plants are loving it :)
The plants in the pond are thriving - need I say any more...?


  1. Excellent idea, Dani! You've done a fine job of solving that problem. I agree-the job must be kinda "ick!", but once a week isn't so bad.

    1. Sue - Thank you :) LOL - I try and push it to every 10 days...

  2. Dani - that is just freakin' brilliant! good on ya!

    your friend,

  3. Very Cool Dani. Now you got my wheels to spinning. I might just have to do something like this. Right now my aerobic septic system handles the full load of the house and it would be more cost effective to do a grey water system for the washer and sinks. I just need a good place for it to grain to.

    1. MDR - Thanks :) The water in the pond is almost crystal clear - so it definitely works. Save your aerobic system for the waste that needs it most :)

      Create a small pond like we did - the wildlife loves it :)

  4. Not just a pretty face Dani! That's a brilliant system and very easy to install (even with the sock cleaning required). I'm sure it won't be long before there are some happy creatures in your pond

    1. EB - LOL Necessity is the mother of invention, and smelly grey water is not pleasant. The pond is already the watering hole for various birds and home to frogs...

  5. Replies
    1. Sprig - LOL - as RMan says - my squatter tendencies come in useful sometimes :)

  6. Well done, Dani. Simple, elegant, low-tech solution. We homesteaders just have to keep thinking outside the box. Thank you St. McGyver! :-D

    I hope your little watering hole thrives!

    1. Kris - Thanks. Oh, the little watering hole is a happy, and an aesthetically more pleasing, little spot...

  7. Dani,
    Thanks for such interesting and descriptive pictures.
    Here we have no municipal water and no wastewater arrangements and so we are on our own well and our own septic tank. In this county, grey water is SUPPOSED to go into your septic. However, I know that for years my parent's grey water left the house and was used for amazing plants. They kept the septic nice and healthy.
    I have a sink in the barn a great distance from the house, and so a grey water "treatment tank" is just the ticket.

    1. Jane - WHY would you HAVE to add grey water to your septic tank - makes no sense? All you're doing is adding "mass" to your tank... Or do you use a drain field?

      As long as your use low chemical cleaning agents, why not use the water for something else?

  8. We have a septic tank for the house. The outbuildings, the studio, the garage and barn and the kennel are all substantial distances from the house and therefore the septic tank. They need either their own septic tank (which will occur when pigs fly) or some other way of dealing with grey water. The barn especially could benefit from the system you demonstrated.

    1. Jane - It's a simple system - but it works :)

  9. Wow, just wow. We have been wondering what to do with our gray water as well. Our septic tank is small so I've been wondering about an alternative. Great solution!

    1. 1st Man - Thanks - glad to have been of assistance :)

  10. If you have reeds growing in the grey water pond, you can harvest them as mulch. Ultimately returning the nutrients to your garden beds and plants.

    1. Diana - Good idea - thanks :) Had my eye on some reeds just up the road, all I need is RMan to dig 'em out for me... LOL

  11. I heard that barley straw and bull rushes can be used to purity pond water as well.

    1. Brat - Heard that too. Question is - where to find barley straw...? :)

    2. first find your barley farmer. Some of our 'wheat fields' are barley.

    3. Reckon asking at the local Co-Op may help :)

  12. Wow, Dani, thank you! I knew there was a way to do this without getting all "sciencey". You've saved me so much time & money!

    1. Debi - Welcome - and thank you for taking the time to leave a comment. This works, as long as you clean out the "trap" frequently. Leaving it for too long results in a very gunky sock, and sludge building up on the top of the sand ;)


Thank you for taking the time to comment - it makes my day and removes the "loneliness' of sitting at my screen blogging supposedly to myself ;)