Anyone able to give me a hand with this one?? In my basement, the main septic line enters our house about 4 feet off the floor. Right next to that there is a "drain" for what used to be our laundry room (we have since moved it upstairs). For a couple months now, and only at certain times, when we flush one of the toilets in our house (we have 2), sewage comes out of that "drain" in the basement. I had the septic system pumped, thinking that might help... no luck. I removed the toilet, and snaked the drain (25 feet worth)... no luck. I snaked the "drain" in the basement... no luck. Do I have a clogged air vent?

Any help would be greatly appreciated.

Thanks in advance

I had this problem a couple years ago, It was because some sort of animal had crawled into the roof vent got stuck and died. (the cover had blown off during a recent storm)

Thanks DLBart... turns out I had a clogged main septic line from the house to the septic system... I got it cleaned out (I'll be talking with my family about TP use :-) tonight), and everything is good as gold.