I have a open 4" cast iron floor drain in my basement that a sink 5 feet away empties into through the floor. The floor drain then runs to a stack with a clean-out about 12 feet away that heads out under the floor to the septic system.

My problem is that the discharge from my water softner when it recycles runs into the sink and the floor drain overflows on the concrete floor. Since there is always about 8-10 inches of standing water in the floor drain and no sewer odor, I assume there's a trap of some sort under the floor at the floor drain. Btw, the drain does not overflow when I just run the water into the sink...only when a large continuous volume is dumped into the sink.

I'm fairly confident that the overflow is caused by a build up in the pipe running from the floor drain to the stack and I need to have it cleaned to restore proper flow. Everything from the stack to the septic tank drains and flows fine.

I have a few questions that hopefully someone on this forum can answer for me.

1. Assuming there's a trap at the drain under the concrete floor can some type of powered snake or drain cleaner be navigated through it and the line to the stack to clean it out?

2. If not, can some type of powered snake or drain cleaner be fed through the clean-out in the stack directed back toward the floor drain instead?

3. Is there another way to clean this line from the drain to the stack area?

I will probably hire a plumber to do the cleaning, unless someone identifies a fairly easy DIY'er method that I can perform, but would like to know in advance the best way as well as possible ways to clean it out.

Thank you for your help.