You don’t miss your water until your well runs day – country proverb

FACT: An average American family of four generates about 70 gallons of graywater a day!  That is a lot of water going down the drain.

For comparison the average African family uses about 5 gallons of water each day.

What is Gray Water?

As its name connotes, graywater is of lesser quality than potable water, but of higher quality than black water. Blackwater is water flushed from toilets. Also, water from the kitchen sink, garbage disposal and dishwasher usually is considered blackwat er because of high concentrations of organic waste. Graywater derives from other residential water uses. Water from the bath, shower, washing machine, and bathroom sink are the sources of graywater.

Gray water composes 50–80% of residential wastewater  generated from all of the house’s sanitation equipment (excepting toilets).

The best method of reusing gray water, without using expensive treatment and disinfection methods, is through sub-surface irrigation which we just finished here on the urban homestead.

New CA Code

The State of California recently revised its plumbing code to allow simple gray water systems to be installed without a permit (this is bathtub/shower/sink/laundry water) for use in landscape irrigation.

Homeowners are still supposed to follow regular gray water regulations, which include not putting the water directly on parts of a plant to be consumed by people (so not on lettuces, greens, etc) and not allowing the water to  exposed to the air, standing contained more than 24 hours.

Summary of the new code:

* no permit needed for a washing machine system if the system followed health and safety guidelines outlined in the code
* no permit for a singe fixture (one shower) if guidelines are followed
* mulch basins allowed (instead of gravel)
* other systems are separated into “simple” and “complex” depending on the quantity of water. There are less requirements for “simple” systems.
* depth of discharge is 2 inches under mulch (it used to be 9″ under dirt)

:: Resources ::

Gray Water and Soaps / Do’s & Don’ts

Create and Oasis with Gray Water

Water Conservation Using Gray Water

Laundry to Landscape

:: Products ::

Toilet Lid Sink


  1. Laura @ Getting There says:

    The house we are living in, we rent, so we can’t install a greywater system. But what I do, is in the summer I carry water down from the bath tub after the kids have had their bath in the evening, in bucket loads, and pour it on the flower garden. I must be dedicated to saving water, because we live in a three story house–and the bath tub is at the top! 🙂

    • Lura says:

      @Laura @ Getting There, try siphoning it out with a hose – much easier than a bucket

  2. Brad says:

    You rock Laura! Important correction for the definition of graywater in this post… graywater can be of greater quality than potable water for irrigating plants due to the presence of additional nutrients. Hooray for the plumbing code revision 🙂

  3. Ben says:

    Just curious about what you have to use as laundry detergent in order to use the water for plants.

    I would assume the standard store bought detergent (Tide, etc) would contain crap that would not be good for the plants or people eating them.

  4. CE says:

    Laura might try coiling a couple feet of garden hose in the bottem of the bathtub. Put a weight on it. ( A child would work). Then drop the rest of the hose out of the window but hold onto the end. Suck hard on that end and when you can feel a bit of water leaving the tub and going into the hose, lower your end out the window. You should feel the water moving further into the hose and once it gets over the window sill ( that is the hard part) it will run very fast so someone needs to be down below or lower the end into an empty garbage can and fill-er-up. Hope this works for you. It will be less work once you get your system down.
    I am a bathtub water hauler also.

  5. Grizzly Bear Mom says:

    It appears easiest to me that after you weigh your hose with a child, shut in in the window, you could go outside and suck on the hose, right?

  6. Grizzly Bear Mom says:

    Why recycle grey water for if I can’t eat what it grows?

    Why make grass grow only to have to use my and petroleum energy to cut it and create pollution by doing so?

  7. The Front Porch » Blog Archive » Urban Homestead ~ Be Water Wise says:

    […] a few modifications, I think that would be a good place to start.  For more on grey water, see this post at Path to […]

  8. BABY STEPS | Little Homestead in the City says:

    […] 2. Reduced water with installation of graywater to garden […]

  9. 10 Common Plumbing Terms | Top Plumber in Pittsfield, MA says:

    […] A Simple Plumbing RepairsMission Viejo Simple Plumbing RepairsPlumbing Jargon You Might Find HelpfulGRAY WATER RECLAMATION #rotator { position: relative; width: 610px; height: 300px; margin: 0; padding: 0; overflow: […]

  10. melody says:

    Is there a way to recycle vegetable & waterwaste after its run through a garbage disposer? and can it be tied into a greywater system in some way?

  11. john paul says:

    Enjoyed reading this post and the subsequent comments. Cheers for CA revision of the code. I am preparing to build a home on 13 mountain acres in the upstate of South Carolina. The location has no public water or sewer availability. When I went for my septic system permit I asked for a double system – so as to allow for the installation of a gray-water system for the house. I was told I could not have one because it is illegal in the state of South Carolina. What stupid law makers we have…

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