RE: 650 square foot seasonal cabin in Northern Michigan. Have only a septic tank at present, no field through a 4" ABS pipe. Can and if so where can I connect the shower drain, bathroom sink drain, kitchen sink drain, and laundry drain to the existing toilet (water closet) drain - before the toilet drain or after)? All will terminate into a single 4" pipe to the septic tank. The toilet is the only fixture currently connected to the septic tank. All of the other go into a dry well which has been getting saturated with the load and needs to be eliminated.
Have heard something about other drains not being allowed on a toilet drain. Then how and where do I connect them all to the single line to the septic tank. And do Studervent's work ok? Would use one for the bathroom and another for the kitchen sinks. The shower would be vented along with the toilet up and out the roof. Is code 4" one foot on each side of the roof minimum for vents? Can a 4" ABS pipe be connected to a DWV plastic pipe (solvent welded?) Thanks.