crazy drain

I can't figure out this drainage problem, perhaps someone here can enlighten me. Today water began flooding out from under our hardwood floor in a hallway between a bathroom and our laundry room. The washing machine had just been running and the water had some soap in it so I assumed something was wrong with the drainage system from the washer. I pulled out the washer and under a trap door in the floor there is a little sink where the pipe that runs down the wall from the washer drains. It was all wet all around it so this was obviously where the water had flooded over to come up under the floor just on the other side of the wall (our house is on a concrete slab)... I snaked it and it seemed clear. I ran a garden hose down both the pipe from washer and the drain in the little sink and it drained just fine. Here's the strange part... when I flush the toilet or run the tub it backs up into the little sink and takes forever to drain back out again. How can it be that it drains when I pour 50 gallons of water into it from a hose, but backs up when I flush 2 gallons from a toilet? I am stumped.

Sounds like a clogged drain... All the water you poured in from the hose filled the pipe and now the toilet overflowed it. Get a drain cleaner over.

you'd think so...

... but after the toilet back up, I ran the hose again, and again it drained with no problem... I snaked the toilet just to be sure, came up clean, and then for good measure the big inlet outside the house coming from the bathroom (I ran the hose into that as well with no backing up anywhere). Snaking the tub is next but I have to recharge the battery on my power drill from all this snaking. I hesitate using liquid openers cause if that came up under the hardwood floor it wouldn't be pretty.

With a drill snake I sincerly doubt you will accomplish anything. You my friend are battling a dragon with toothpicks.

I see... I am pretty good at most house-related problems, but I will be the first to admit that plumbing is not on that list. I thank you for your time and I will take your advice and call a professional dragon slayer in the morning (how do those dragons get down in the pipes anyway?? bet it was my 4 year-old!). Thanks again for your replies... Ted

I'm curious about the "sink" in the floor. That sounds like a bungled bit of hardware to me.

Herk said:

I'm curious about the "sink" in the floor. That sounds like a bungled bit of hardware to me.

Click to expand...

Seemed a bit odd when I discovered it too. There is a small wooden platform that the washer and dryer sit on, the washer drains to a pvc pipe that goes down inside the wall and fits into the drain in a small (prob 1 cubic foot) sink that is at floor level under a trap door in the platform. The drain in the sink would be about 12" below the floor level, and as I said our house is on a concrete slab with no foundation (which I was very thankful for after the Northridge quake when my neighbor who's house has a foundation had to all but rebuild his entire house and we only had a little plaster damage).
It has obviously worked pretty well, as strange as it seems, as I have owned the house for almost 20 years and only discovered it day before yesterday when it backed up.

So your washer is an indirect drain going to a scupper under the platform... Doesn't sound great...