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Community and Q&A

Kitchen Waste Water

Lacunatx | Posted in Green Building Techniques on

We’re building a small cabin in a remote region of central Texas with limited restrictions. OSSF site certification through the county is the only inspection we need to pass. We want to conserve water and would love to use a composting or incinerating toilet with grey water irrigation for our garden without installing septic. Unfortunately, Texas considers kitchen wastewater as black. Has anyone found a way to filter kitchen water that meets code in states that designate it as black water? Perhaps through the experimental sections of the code? We are open to any solutions. Thank you!

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  1. DC_Contrarian | | #1

    I think you need to do what's called in the trade a "post-inspection alteration."

  2. nynick | | #2

    Composting toilets seems ok in theory, but they take a lot of 'getting used to'.
    Visitors aren't particularly happy about them either.

  3. jameshowison | | #3

    Yeah, this discussion of first Austin whole house grey water permit does seem to exclude kitchen water.

    I wonder what makes something kitchen water?

    1. Lacunatx | | #4

      That's a great question. We only have one sink in this tiny cabin...maybe I need to look into arguing that it is a bathroom sink not used for food disposal (because we compost all that anyway) rather than planning elaborate and unnecessary blackwater treatment systems. There are simple effective ways to treat kitchen water that other states allow, just not Texas. I'll look into that further. Thanks!

      1. DC_Contrarian | | #5

        Are you subject to code? Is it permitted as a dwelling? If so, it's going to need a kitchen. And that kitchen needs a sink.

  4. ben_strasheim | | #6

    Not a code expert here, but I believe kitchen water is considered blackwater because of the animal products (meat, dairy, egg) that may get washed down the drain. Bacteria and odor would be the big concerns on an untreated outlet.

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