Digging for drainpipes

[nobleswood]

I am a procrastinator.

This sounds like the start of an AA meeting 

I am a procrastinator & if I'm not sure of how to do something, I'll research, but this can easily become 'Doing something other than what I should be doing'.

So here's my problem & I thought I'd ask the combined knowledge here for sound advise, as I am often amazed at the broad range of knowledge & experience on WildGuzzi.

I have to install drainpipes on my property. Ok no problem. House was built in 1938 & used clay tile/pipe for the drainpipes, septic tank etc. To mow etc I have a Kubota L 185 small tractor. The weight of the tractor going over the clay tile drainpipes has created a depression so I'm assuming they are crushed  or broken enough to need replacing.

Whilst initially I was thinking of Schedule 40 rigid pipe, how deep would you have to bury the pipe to overcome the tractor problem ? I presume the pipe needs to be in 3" of gravel to allow for flexing. The pipes will go from the top of the ridge down the hill to the pond & all of my land is Ohio clay.

The flexing problem brought me to using the black plastic pipe, as seen at Home Depot etc. Whilst this would be able to move, could it cope with the load of the tractor?

I am loath to sweat & strain digging  & putting in the pipe only to find next year that it's failed in some way next year cos I didn't understand how it should have been constructed

Whilst thinking about this..'Squirrel!' sunny day, I'm off for a ride.

Management  would like to see some movement on this project as I'm home with the time.

Advise please

[John A]

Call the diggers hot line so they mark the gas and electric lines,  then put out some of your own markers where you want your lines might go.  That’s the all important visual progress 

[Perazzimx14]

Is the area often wet and/or soft? If the ground i stable a 12" bury depth is plenty with suitable backfill as plastic is very resilient if crossing over it at a 90 degree. If the tires are running with the pipe burying  deeper is better.

The rub is since you are relying on gravity to drain the current bury depth might be as good as it gets. The good news is PVC will take a lot more weight then terracotta.


If you are talking about sewer DO NOT use corrigated flexable pipe.

[Ncdan]

Call a respectable septic service and have professionals to do the job. In the long run you’d be glad you did. I’ve been there.

[nobleswood]

Answers in order;

Gas, electric & phone lines have been marked.

The tractor has lawn tyres on it with 12 psi pressure & do a good job of not leaving an imprint. So if I am running with the length of the pipe, how deep to bury the pipe ?
What do you consider a suitable backfill other than the clay soil I dug out ?
The ground is not wet or soft but it is clay & moves.

The septic system is another project & can of worms.

[rocker59]

Use schedule 40 PVC.  You'll crush the flexible black french drain pipe.

[Murray]

Answers in order;



The tractor has lawn tyres on it with 12 psi pressure & do a good job of not leaving an imprint.

Might be worth doing some gentle exploration with the shovel, you either have some kind of leak before you drove on it or the pipes are very shallow indeed I would not expect that kind of pressure to cause a failure.

[Perazzimx14]

Answers in order;

Gas, electric & phone lines have been marked.

The tractor has lawn tyres on it with 12 psi pressure & do a good job of not leaving an imprint. So if I am running with the length of the pipe, how deep to bury the pipe ?
What do you consider a suitable backfill other than the clay soil I dug out ?
The ground is not wet or soft but it is clay & moves.

The septic system is another project & can of worms.

You will want to use either sand or 2b stone. You also want a 6" sand or stone bed under the pipe then cover with another 6" of sand or son then backfill the res of the ditch with suitable dirt. Suitable means not to dry or sopping wet. If you can for a ball with eh dirt by hand and it stays then it is suitable. This means your ditch will be a minimum of 25" deep. If you need to add more than 12" of dirt you should compact it in 12" lifts. By compacting I don't mean stomping it down with you foot or patting the dirt with the back of a shovel. A vibrating plate compactor or jumping jack should be used.


12" above the pipe
4" pipe is 4-5/8" OD
6" of stone bed under the pipe
-----------------------------------
25" minimum ditch depth


SDR 35 or sch 40. I'd also advise you not go to the local home center if using sch. 40 pvc as it will most likely be foam core. Go to a plumbing supply house that sells to the public and get solid core sch. 40 pvc.   will work and since you only dealing with a lawn tractor even running with the ditch 12" from finish grade to top of pipe will be fine.

[nobleswood]

Perazzimix14, thanks that was the information I needed but feared hearing.

Better get figuring out my shopping list.

[Groover]

Well, if it helps any, I just had some sewer problems last week and called Eco-Plumbers to snake it, They ran the camera, and traced all the bad spots that need work (eventually). At about 60' from the house, the 6" pipe was at 3'-4" deep, and then at about 82' it was 3'-11 deep, and 8' deep where it taps into the city sewer.

All this was done with permit work and inspected in 2010, so thinking it's to code. The issue however is the contractor skimped on back fill gravel and now 10 years later we have a 25' stretch of bellying causing the issue that eventually I'll deal with...

[80CX100]

The issue however is the contractor skimped on back fill gravel and now 10 years later we have a 25' stretch of bellying causing the issue that eventually I'll deal with...

     I had to deal with a similar problem here a few years ago, thankfully my neighbors were professional septic installers and helped me solve the mystery.

     I thought my tank was full and not allowing good drainage, but upon close inspection my problems were caused by settling in my 30' ABS/PVC? drain pipe from the house to the septic tank, where a large section of pipe had bowed down in the middle due to improper tamping of the material on installation.

     To the OP, I won't go anywhere near my septic system with my tractor, but it sounds like you don't have a choice; once you have a good grade for your installation, pay particular attention to tamping down the material under the pipe for support from the bottom.

      Iirc the contractor used clear stone to back fill around the new straight drain pipe, then just regular fill to finish off.

      Good luck

      Kelly

[nobleswood]

These are the sort of issues I want to avoid & why I asked.
Thanks to all who replied.

The septic is another expense that I’m going to leave to the professionals