Underground electric/drainage question

[yanmars]

From the transformer an underground electric line is going to be ran to the house. It will be in 4 inch schedule 40 PVC. It needs to be at least 36 inches underground. The area it runs tends to get wet. After the electric line is it reasonable above the PVC to place a 4 inch perforated plastic farm drainage tile? I would already have the trench open and could easily place the farm drainage tile in and connect to other tile to help drain the area. I could put some fill material between the two.

 

[Bill Guenthner]

I thought the national code required metal conduit, but in any case the conduit should be sitting on and covered with #2 crushed rock and then cloth and hazard tape and then the top soil so that anyone digging will hit the rock and see the tape before they hit a live wire. The rock will act as a French drain and keep water out of the conduit.

 

[jyoutz]

I thought the national code required metal conduit, but in any case the conduit should be sitting on and covered with #2 crushed rock and then cloth and hazard tape and then the top soil so that anyone digging will hit the rock and see the tape before they hit a live wire. The rock will act as a French drain and keep water out of the conduit.

All good ideas. I’m not aware there’s a national code requirement for metal conduit. My lines are in schedule 40, and that’s all I see contractors using.

 

[yanmars]

The farm tile would be above all of the others. Maybe only 2 feet deep to also help in drainage of the area, not just the electric line.

 

[Bill Guenthner]

All good ideas. I’m not aware there’s a national code requirement for metal conduit. My lines are in schedule 40, and that’s all I see contractors using.

It wouldn't surprise me. I just know they put in metal with PVC risers when they did mine.

 

[Bill Guenthner]

The farm tile would be above all of the others. Maybe only 2 feet deep to also help in drainage of the area, not just the electric line.

Can you grade a shallow swale to keep water from standing where the line is?

 

[CobyRupert]

It doesn’t matter if conduit or cables get wet, or ends up being flooded.
Unless you need to install drainage for some other reasons, it’s unnecessary.
Plus, will tile above the conduit really effect the water table under it?

 

[hube2]

Plus, will tile above the conduit really effect the water table under it?

That's what I was thinking when I read OP. Might help drain the area but it won't affect anything below the level of the pipe. The drain pipe would need to be below it.

 

[yanmars]

I am trying to drain the area above the electric line, just have easy access to do it when they trench for the electric. Did not want to do a separate dig in the same area.

 

[grsthegreat]

5” pipe.. seriously. I have never seen 5” pipe and ive been an electrical contractor for over 30 years. PVC pipe is used underground here . Metal pipe would rot away In our soils…..not even allowed to be used. Guess different states could require different materials. How many amps are we talking here.

just for the heck of it, i checked my supply house for 5” pipe…..$160 per 10 foot stick. Yeiks.

 

[yanmars]

I typed that in wrong. I got a deal on 4 inch PVC so bought it, the electric company only requires 3 inch but the 4 was cheap and available so I bought that.

 

[hube2]

PVC pipe is used underground here . Metal pipe would rot away In our soils…..not even allowed to be used. Guess different states could require different materials.

PVC is required here as well, and it also needs to be sealed with PVC cement, so actually water getting into the line should not be an issue of you seal it. But stone is not required, just the warning tape above it. This is what they did when they buried the line from my solar array to the house.

I would make the trench wider and put the drain next to the line and not above it. I am not up on the code for this but I'm guessing that there isn't supposed to be anything above it in case you need to get to it. I'd check with whoever will inspect it. If inspection is not needed then... well, I'd do whatever I wanted to do.

 

[LD1]

If your worried about water around the conduit....the tile needs to be under or beside it. Not above

 

[LittleBittyBigJohn]

Around here we are allowed to put water line over or beside the electrical as long as it is 12" away. But the power has to be on bottom if it is stacked. So I would assume drain tile would be fine?

 

[bigtiller]

I would want my drainage tile far away from my electric service line. One or the other may need servicing someday.

FYI - for every foot the tile is deep, it will draw water up to 10 feet from either side, but nothing below it.

 

[grsthegreat]

No matter if you glue electrical conduit or not…
water will get in pipe. Always has, always will. The wires used wont be affected by water. I always pull URD wires in, thats what our inspectors want. Not affected by water.

XHHW rated wire is also great to use in conduit. Thinner insulation than urd, but also waterproof.

 

[ovrszd]

It doesn’t matter if conduit or cables get wet, or ends up being flooded.
Unless you need to install drainage for some other reasons, it’s unnecessary.
Plus, will tile above the conduit really effect the water table under it?

I'm with you. And if I were going to use the drainage tile I would place it under the conduit. Over the conduit will do very little if any good.

 

[tshep]

gsr is right.
VA Master Electrician - I was taught UG will always/eventually fill from condensation if nothing else.

If you just wanna' share the trench for other reasons, fine, but you won't prevent condensation, much less the other possibilities.

 

[lman]

PVC is required here as well, and it also needs to be sealed with PVC cement, so actually water getting into the line should not be an issue of you seal it. But stone is not required, just the warning tape above it. This is what they did when they buried the line from my solar array to the house.

I would make the trench wider and put the drain next to the line and not above it. I am not up on the code for this but I'm guessing that there isn't supposed to be anything above it in case you need to get to it. I'd check with whoever will inspect it. If inspection is not needed then... well, I'd do whatever I wanted to do.

UF cable is made to handle moisture. Conduit is not used to keep it away from water.

 

[yanmars]

I was not concerned about water getting into the PVC. I know it eventually will. I just wanted to help drain the area where the electric line will be, just had a free trench to do it in the right location. The farm drain tile would be to dry up the ground above, nothing to do with the PVC electric line other than the same trench.