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Water butt from combined rain and greywater.

Hi again.

I'm looking to get a water butt.  The issue is the only downpipe combines the guttering to the output from our bathroom (a sink and bath only - no toilet of course).  I understand one can use greywater in the garden, though it can cause issues due to soap, toothpaste, hair bleach and cleaning products.

If this is combining the rainwater from the roof will it all be so diluted it won't cause an issue?  I could always disconnect the downpipe while cleaning or when the Fiancee bleaches her hair!

Any input would be appreciated image


  • They shouldn't be connected - the rainwater is overloading the domestic drainage system. If every house did this there would be chaos.

  • Grabs39Grabs39 Posts: 18

    Only applicable in newer properties, Joe.  We still have a combined sewerage system around here.

  • The problem is that combined sewer overflows pollute rivers and the sea. Anything anyone can do to use their rainwater will help, so Grabs could divert his downpipe to a water-butt and a soakaway if feasible.

  • Grabs39Grabs39 Posts: 18

    It's not an overflow, there literally is one drain.  All output from the property, be it drainpipes, soil pipes etc goes down it.  This is very common in houses built before the middle of the 20th century.

    In fairness there should be a separate downpipe for rainwater and soil pipe from the shower, but they would still meet at the drain around 4 feet from the base of the pipes.  As such it's not really worth sorting it out.

    The (small) garden slopes down to the house, so a soakaway wouldn't be feasible.

  • Sorry Grabs, I was talking about large scale overflows much further 'downstream', which come into operation at times of high rainfall. But I was still thinking you could insert a diversion in your gutter downpipe to feed a couple of connected water butts, and leave the hair and toothpaste to go into the sewer. You'll have more than enough water from the roof to feed a small garden.

  • should be able to cut into your gutter downpipe and install a water butt.

    It will prove more than useful and save all the rain water going to wasteimage

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