Deep septic tanks

**SewerRat** · 06-11-2012, 10:21 AM

I saw the deepest septic I've ever seen last Saturday.

Daylight basement with gravity sewer, no ejector. 9' ceilings in basement with full backfill on the non-daylight side. Surely, surely they ran the sewer line out the daylight side of the house, right?

Nope. Scout picks up a very weak signal at the deepest part of the front yard. Probed and found a riser lid about 2' down. Dug it up and pulled the lid, look down a tall riser and sure enough there's the tank exactly 10' below the sod.

Took quite a while to pump. Quite a lift, plus it was pretty bad and we had no way to mix it that far down, so we had to pump, then backflush, then pump, a total of about 4 or 5 times to get the tank clean. No way to inspect anything that far down either.

What's the deepest you've ever seen?

**Colgar** · 06-11-2012, 01:20 PM

I'll find them like that every once in a while. I don't pump tanks, so my experience is limited.

Back when Peoria was booming in whiskey production, the hoity toity whiskey barons built mansions on the river bluff. Some of these are still on septics. They'll be dug in the hill side below basement grade, on a slope so steep you can barely stand up without holding on to a tree. Makes pumping interesting because they are so far below the truck.

**KCJAKE** · 06-11-2012, 02:55 PM

10ft is crazy deep - I found one about 3 years ago that was roughly 7ft deep and about 400ft from the house - fortunately there were about 3 outside cleanouts leading me to the tank...

**dcman** · 06-11-2012, 05:00 PM

That is insanley deep....6 foot is about as deep as we seem them.....

**Hahns Septic** · 06-11-2012, 05:33 PM

Most of the septic tanks we clean are 2-3 foot deep and all have risers that bring the inlet side to 6" of the surface. The deepest i have seen is 5' to the rim of the tank 10' to the bottom

**Trent2** · 06-11-2012, 11:27 PM

I've seen them that deep before. No fun to pump. Only one or two in my career.

**BuckeyeBowhunter** · 06-13-2012, 03:05 PM

we're generally hilly enough that its tough to get one down that deep. Not sure why you'd go out the deep side of the basement...

but lots of times we have enough land contour that you're lower than the house when you get on ground level above the tank.

**gene bickford** · 06-13-2012, 04:36 PM

Riser? Whats that? LOL! not often I see a riser around here.

Normal depth is between 0' and 2'. Not uncomon at all to see them up to 4' deep. Deepest I've located was 6'. After 1' of hand digging the pumper and I told the HO "you need a mini excavator" nothing but rocks for backfill.

Started hand digging one awhile back 4' deep and would have done the same thing, nothing but rocks and shale, but the HO was in a wheel chair (looked to have MS in a bad way) and his mother looked to be about 175yrs old. They where backed up solid and it was late in the day. Exposed the inlet cover as I suspected a baffel clog and thank God I was right.