I’ve been running longer than usual lately, so I’ll revert to “short and…” – well, come to think of it, talking about septic systems probably doesn’t qualify as “sweet.” In fact, it wasn’t at all when someone finally stayed in our little refurbished farm house and had to cover the bathroom floor drain with plastic wrap because of the smell.
When we finally got around to examining the mechanics, the problem was quite obvious. The toilet (which of course has a water trap built into it) dumps into a (how Pompeain!) concrete box. The sitzbad drain goes into the bathroom floor drain, then to this same box outside.
So think about it: the residue from the toilet flows through this box to the septic tank (pozo negro), which then creates smelly gas that wafts its way back up the same pipe and follows the path of least resistance. The toilet is blocked by a water trap, and the concrete lid is more or less airtight, goes where does it go? Up the pipe to the floor drain, of course!
The solution was simple, and took just a few minutes: stick in a cut-off sifón (kitchen sink thingie) and make a little trap. The water in the bottom of the “U” stops gas in its tracks. (“Stop gas in its tracks!” I should be in advertising.) Anything to the right of the “U” I could cut off, but I left just because. You. Never. Know.
Since I didn’t post it in my September 2013 Sitzbad post, I want to mention that the plumbing fail I describe here was balanced by ingenuity, a solution to the “geyser” problem of the floor drain when emptying the sitzbad. The next day Martín returned with one of his daughter’s glass marbles, dropped it into the bath drain, and – pim pam pum – problem solved! The marble reduces the flow by 75%, and it works!
I’ve mentioned before (I’m sure) that Uruguayans can be incredibly resourceful. Had we actually been using the farmhouse with its one bathroom, I have no doubt Martín would have sorted this, no doubt even more elegantly.
On the other hand, in testing this, when I went into the bathroom to turn on the shower/sitzbad water, one of the slate tiles on the step of his sitzbad creation came loose and dropped to the floor.