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Discuss Gray water system _________ in the Renewable Energy area at

  1. Loubanez

    Loubanez Member

    Hello all,
    As of late I'm becoming increasingly aware of the amount of clean water I'm wasting by flushing the toilet, I want to create a Gray water system that recycles the water from my shower/bath and then pumps it back to the toilet.
    So far I'm in the early stages of thinking through this, i have an old brick outhouse/ which could be a suitable place to store the collection tanks. What I want to ask is what would be a suitable pump to use to pump the Gray water back to the toilet? Probably about 4 metres with a 35- 40d incline, also some sort of on/off, switching, flow switch? I'm no plumber and I'm trying to educate myself.
    Has anyone ever installed a similar system Or got anything they could add?
  2. johnduffell

    johnduffell Member

    Sounds interesting but i am not sure how to do it. Following with interest.
    I would be concerned how can you keep the tanks clean?
  3. rpm

    rpm Trusted Plumber

    If this idea is to save on the water bill then I`m thinking it will be awhile before you get the outlay involved back tbh.
  4. Loubanez

    Loubanez Member

    Can't really see a great deal of outlay I would be doing all the work myself, I've calculated that I use about 70 litres of water a day on flushing the toilet which would be about 30% or more of my daily water consumption, I'm on water meter aswell and just got hit with my bi-annual bill,
    As for maintenance I'm thinking some sort of bypass system so the tanks could be cleaned when necessary.
  5. Loubanez

    Loubanez Member

    Also it's more of a hobby/challenge something to do over the summer.
    • Like Like x 1
  6. ShaunCorbs

    ShaunCorbs S. Mod Trusted Plumber GSR Top Contributor!!

    Problem is that you will need to repipe your feed to the toilet so underfloors etc

    It's doable but a bit of work

    Have a look / phone pump world up for the pump and container
  7. rpm

    rpm Trusted Plumber

    Average shower use is around 50l a time if that helps your calculation for size of tank required.
  8. Chester

    Chester Member

    Not something I would be too happy to retrofit personally, bit of a mission and considering the price of water it will be a while before you've got your money back.
  9. Pintsize

    Pintsize New Member

    Watching with interest, be having an extension soon, could be an option.
  10. Murdoch

    Murdoch Active Member

    The perfect time to do major works like this IMHO

    I think all new German houses have these systems...
  11. Loubanez

    Loubanez Member

    Yes admittedly their will be some disruption to the house but the bathroom at the moment is back to brick so plumbing two pipes in for the toilet and a diverter valve on the waste shouldn't be a problem, anyone got any suggestions on a suitable pump, pressurised pump?
  12. gmartine

    gmartine GSR

    Grey water is manky and requires cleaning even for toilet use, why not go for a rainwater harvesting system and a header tank supplying the toilet. That way the pump only operates when refilling the tank rather than every time the toilet is flushed.
    • Like Like x 1
    • Agree Agree x 1
  13. oz-plumber

    oz-plumber Plumber

    A few years ago, we were on water restrictions because of drought.
    In Melbourne we were restricted to what we could use water for.

    Grey water systems were all the rage - now we're pulling them out.

    Without going through all the pitfalls, basically, the tanks were meant to be emptied once every 24 hours, to stop bacteria growth.
    The water wasn't allowed to be dispersed above ground level, if you wanted to water your garden - underground drip feed system.

    Of course people avoided this and ended up with tanks full of algae and the like. Stuffed up pumps, stuffed up cistern inlet valves, blocked water lines and so forth.

    At the end of the day, I would prefer to unblock someones sewer than their grey water system - I felt it healthier!!!

    On the other hand, rainwater tanks were installed and are still operating with minimal problems.
    Many pump manufacturers make tank water pumps connected to the mains water and switch automatically between tank water and mains when the tank is empty.
    The other option was to put a ball float valve in a tank that would keep the tank with enough water in it to flush toilets, if you hadn't got enough water from rain.

    Hope this helps
    • Like Like x 2
    • Informative Informative x 2
    • Winner Winner x 1
  14. Jack bIRCHLEY

    Jack bIRCHLEY New Member

    Hi rather than use grey water why not use your tanks in the shed to collect rainwater from the roof. I have done this for toilet flushing, car washing and garden watering. It cuts down your water bill and your sewage bill. Its easy to install with a self priming pump and a pressure switch.
    • Like Like x 1
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