4" DWV PVC gray water line crushed! Man am I PO'd!

[MasterMech]

Well, we've owned this place for 4 years now and the gremlins are starting to surface. Last fall, I noticed the garden behind the house would get wet whenever we took showers or ran the washer, etc. It got worse over the winter with a standing flood every time we ran more than a bit of water. I finally get Around to digging up the line and here's what I find. The line is crushed all the way back underneath my deck and I have good reason to suspect it is compromised further down towards the drywall as well! I really hate to do it, but I guess my best option is to divert to septic since if the addition the wife wants ever happens, I will be forced to do so anyways. Anybody know what went wrong here?

 

[USMC80]

is that sch 20 pipe?

 

[MasterMech]

is that sch 20 pipe?

I'm not a plumbing expert but maybe DWV and SCH20 are similar? Pipe is white PVC on the outside and has a black liner inside.

 

[gzecc]

Wouldn't scedule 40 be the better choice?

 

[USMC80]

thats sch 20 pipe, that is part of your problem right there. They should have used sch 40. You can crush sch 20 by just stepping on it

 

[Highbeam]

That's gutter pipe. Cheap pipe but can be installed without crushing if you take time to bed the pipe. There is certainly no reason for it to crush at that depth and under a slab if installed properly.

Is there any way that you can drive a thicker walled 3" pipe through it back into the home? I would rather have a high quality 3" pipe (probably matches the plumbing in the home) than a smashed and leaky 4" pipe. You can typically nest one inside the other.

So that we all understand this.... you have a septic system for toilets and then a drywell for your laundry and shower?

 

[USMC80]

Highbeam is correct it can be used if installed properly but I would recommend always using sch 40. It's quite a bit more expensive but you would never have to worry.

 

[MasterMech]

Highbeam, you're correct on how my system is setup. I was quite happy with it but I'm told that I will have to abandon the drywell if I do an addition (that includes any plumbing) due to local building code. That's too bad since I had both systems pumped this spring and both appeared to be in excellent shape. The septic barely had any solids at all.

This line is about 3' down at the point where I dug it up. I wouldn't have chosen this stuff as my first choice in pipe and it doesn't appear that any special precautions were taken during installation. No sand, gravel and rock right up against the pipe.

 

[ironpony]

agree with all the above, that is sch 20 drain pipe, you need schedule 40 DWV pipe. I know around here after it leaves the house it has to be 4 inch for local code.
it is still suprising it crushed like that buried 3 feet deep
also for clarification Sch 20 vs Sch 40 is the wall thickness of the pipe

 

[343amc]

Ouch. That brings back memories of when the pipe between my septic tank and house collapsed 10 years ago, except that was Orangeburg pipe. Easy to remove as it could be sliced with a shovel.

 

[Highbeam]

We run into lots of orangberg pipe here at work. That stuff is like tar paper rolled up two layers thick. It gets soft and collapses like a noodle. I would much rather have the lightweight PVC than orangberg.

 

[DJB]

yeah, there's no reason for that pipe to be that mangled. I'd expect orangeberg to look like that, but not sch 20. the sch 20 can flatten out with too much weight on it, but to split like that, something had to crush it, or run over it, seeing that it's under your deck, this had to occur quite some time ago. you could try to stuff a 3 inch line up it, but it looks like its too far out of round. If its only carrying water, you could get away with a 2 inch line, at least until you get out from under that slab, then switch to 4 inch where you can dig a new trench. I'd put a cleanout at the edge of the slab, also.

 

[pen]

We run into lots of orangberg pipe here at work. That stuff is like tar paper rolled up two layers thick. It gets soft and collapses like a noodle. I would much rather have the lightweight PVC than orangberg.

House is 51 years old and just last month I dug up the line from the house to the septic and replaced the original orangeburg pipe. Can't believe anything was moving through it, but it did.

Schedule 40 went in it's place. I don't mind using a pick and shovel to do a job, ONCE.

To the OP, if it was a working drywell, and it's only problem is that pipe, then keep it and just add the addition's water to the septic???

I built a garage last year that was very close to my cesspool (dry well) by code. I think I had to keep 15 feet from it and that's pretty much exactly how far it is away, give or take. Anyway, code officer looked at the ground and said "It's working, do whatever you can to keep it that way for the sake of your septic."

Had the septic pumped after replacing the inlet line, it had been 6 years and it was working great. The septic pumper guy who generally recommends 2-3 years for septics in my area said there was no reason to do this more often.

pen

 

[peakbagger]

Orangberg pipe appears to be the same as Bermico pipe that was made in Berlin NH for many years. There is lot of it in the ground in the region and it doesn't have a great reputation for longevity. Generally if plastic pipe is properly bedded in sand and then backfilled correctly it rarely fails. If its shallow and in clay or under a surface that gets cleared in the winter, frost can raise havoc with it.