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Land has only 1 1/2 feet of dirt on top of solid rock — so what about septic?

what is a screen name | Posted in GBA Pro Help on

I bought land which is zoned residential without doing a perc test. The dirt is at most 1 1/2 feet deep on top of solid rock. I could do a compost toilet, but I was told I would still need a septic tank to handle the gray water. What do I do?

I don’t know what you want for more explanation.

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  1. Expert Member

    You need an engineered system. There are a variety of different ones from sand filters, manufactured wetlands, to simple aeration. Unfortunately they are all very expensive but a system can be designed for almost any lot.

  2. davidmeiland | | #2

    Yes, get a septic designer and/or installer to figure out the most economical design that will do what you need done.

  3. keithhoffman22 | | #3

    Juanita, we tried to buy a house with a very high water table awhile back. We didn't get the house (or build the system) but what all the septic guys I talked to suggested was a raised bed system. I believe Malcom is referring to the same idea with the term 'manufactured wetland'. As i understand it, they import soil and sand and make an area large enough for your leach field. You'll also need to figure out where to put the septic tank since in the ground won't work. Have you talked to septic companies in your area? They will be able to talk about what works locally and what kind of costs might be involved. Good luck.

  4. GBA Editor
    Martin Holladay | | #4

    Remember, there are two aspects to this question. The first is the engineering aspect; as the other responders have noted, you need a qualified expert to design your septic system

    The second point is the legal aspect. You'll need to research legal requirements for residential septic systems in your area. These regulations vary widely from state to state and town to town. Contact your local building department or health department to make sure that you understand the legal requirements in your jurisdiction.

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