Main drain depth exiting cottage for septic line connection

Discussion in 'Plumbing Code Questions' started by chuck b, Jun 23, 2011.

  1. chuck b

    chuck b sea-bee

    Joined:
    Jan 19, 2011
    Location:
    levering, michigan
    Have smallish 650 sq. ft. cottage in Northern Michigan - seasonal for non-winter months.

    Replumbing entire DWV system, and need to know what depth to exit cottage for future new septic system (elevated-engineered system) connection.

    Have heard conflicting stories, e.g. top of (3" sch. 40 pipe in my case) at least 8" below ground level.

    Please advise. After exiting, will travel short distance to dousing tank - grinder pump then some 300' to field.

    Thanks.
     
  2. hj

    hj Moderator & Master Plumber Staff Member

    Joined:
    Aug 31, 2004
    Occupation:
    Plumber
    Location:
    Cave Creek, Arizona
    You install the plumbing inside the building, and then they install the septic tank wherever it has to be so the pipe can be connected. I have had tanks 18" below the ground, and also 10' down when there was a basement.
     
  3. Sponsor

    Sponsor Paid Advertisement

     
  4. Smooky

    Smooky Member

    Joined:
    Apr 4, 2011
    Location:
    NC
    I would put it at least 12 inches deep so your tanks will be below the ground surface. The depth of the tanks should not matter unless you have bedrock near the surface or a very high water table that could cause installation problems etc. Since you are pumping the sewage the depth is not as important. Sometimes for a gravity system you would have to keep the plumbing high if the drain-field was being installed in a raised mound or required to be installed ultra shallow because of the water table etc.
     
  5. hj

    hj Moderator & Master Plumber Staff Member

    Joined:
    Aug 31, 2004
    Occupation:
    Plumber
    Location:
    Cave Creek, Arizona
    Since the opening in the tank is usually 12", OR MORE, below the top, a pipe 12" deep would put the tank at or above the ground level.
     
Similar Threads: Main drain
Forum Title Date
Plumbing Code Questions Underground Branch Line Ok to Cross Over Main Waste Line? Jan 21, 2015
Plumbing Code Questions Main Vent or Stack Vent Required? Sep 16, 2013
Plumbing Code Questions Will this drain vent layout work... Jan 2, 2015
Plumbing Code Questions Washing machine drain diagram (California) Dec 11, 2014
Plumbing Code Questions Drain/Vent for New Bathtub Oct 30, 2014

Share This Page