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McZippie's avatar
McZippie
Explorer
Aug 07, 2013

Bathroom sink bypass drain

DW just has'ta shampoo her hair everyday. She was filling up the waste tank, so modified the sink's P-trap with a valve that can divert waste water to tank or directly to the ground.



  • TakingThe5th wrote:
    We generate a good amount of grey water too. I am happy with my grey water flush system because it keeps the grey water tank level down while extending our fresh water.

    Found a 2nd use for grey water. On one trip we had a lot of leaves on the campsite and couldn't seem to keep them away from the campfire. I hooked a hose to the cap on my dump discharge and ran the hose near the campfire. Before we would leave the campfire unattended I would open the grey water valve and put out the fire with the hose. That was a gravity-feed system. My next mod will be to tap into my grey water flush system for grey water under pressure.

    I don't mean to steal your thread, just wanted to give you some alternative thoughts on getting rid of grey water. Hope this helped.


    That's a great idea! Any others with creative grey water mods?
  • TakingThe5th wrote:
    You have tapped into your p-trap, which is designed to prevent sewer gases from entering the living space. Your modification drains all the water from the trap, which is liable to raise a stink in a very real sense. The DW might be breathing these gases as she washes her hair. If you continue to leave it open afterward you may be in for some more "surprises".


    Thanks for the caution and yes I'm aware of the sewer gas problem. Only open the valve when she shampooing.
  • We generate a good amount of grey water too. I am happy with my grey water flush system because it keeps the grey water tank level down while extending our fresh water.

    Found a 2nd use for grey water. On one trip we had a lot of leaves on the campsite and couldn't seem to keep them away from the campfire. I hooked a hose to the cap on my dump discharge and ran the hose near the campfire. Before we would leave the campfire unattended I would open the grey water valve and put out the fire with the hose. That was a gravity-feed system. My next mod will be to tap into my grey water flush system for grey water under pressure.

    I don't mean to steal your thread, just wanted to give you some alternative thoughts on getting rid of grey water. Hope this helped.
  • You have tapped into your p-trap, which is designed to prevent sewer gases from entering the living space. Your modification drains all the water from the trap, which is liable to raise a stink in a very real sense. The DW might be breathing these gases as she washes her hair. If you continue to leave it open afterward you may be in for some more "surprises".
  • Old-Biscuit wrote:
    That ground dumping could be costly........most places it's illegal to dump on ground.


    Yikes double trouble for us... We also have an outdoor shower that's plumbed into RV's fresh water system, that DW uses sometimes to shampoo her hair on nice weather days. She complained a lot about using the outdoor shower, so rigged up a new faucet and ground drain to keep her happy and the limit amount of waste water going into holding tank. Really no different between using indoor ground drain or outdoor shower as to amount of waste water dumped onto ground.
  • path1 wrote:
    Is that U shaped fitting with down spout available commonly over the counter or is that something you rigged up?


    I rigged it up from PVC, plumbing and garden hose parts. The "U shaped fitting" had a clean out plug that I replaced with a iron pipe coupler. The valve screws into the other end of coupler. Bottom of valve has brass garden hose coupler.
  • Is that U shaped fitting with down spout available commonly over the counter or is that something you rigged up?
  • That ground dumping could be costly........most places it's illegal to dump on ground.

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