Question on conduit burial with natural gas piping?

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herding_cats

herding_cats

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Kansas
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Mechanical Engineer
I have a project I am working on and wasn't sure about the relationship with natural gas piping next to PVC conduit.

In the image the 3 PVC runs are: 12 volt DC, 120vac 20A, and a communications run (CAT6)

The Yellow pipe is a 3/4 inch natural gas run. Is there any reason this cannot be in the same run/burial? Is it best underneath, or next to conduit or does it matter?
 

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There is no NEC Code about it.

There is no Plumbing or Fuel Gas Code regarding kit, not in my area, or any place I have ever heard of.

I have heard of some utilities not wanting *their* gas lines sharing a trench with other (private) utilities, but that is up to the local energy provider.

Many utilities have regulations regarding electrical equipment in proximity to gas meters and such, but again, that’s a local utility provider issue.
 
herding_cats said:
...The Yellow pipe is a 3/4 inch natural gas run. Is there any reason this cannot be in the same run/burial? Is it best underneath, or next to conduit or does it matter?
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I would hate to have to dig below the gas line to get to my conduit if I needed to, I"m sure the gas person would hate to have my conduit in the way if he needed to get to the gas line. Keeping them all at the same depth makes the most sense.
 
ActionDave said:
I would hate to have to dig below the gas line to get to my conduit if I needed to, I"m sure the gas person would hate to have my conduit in the way if he needed to get to the gas line. Keeping them all at the same depth makes the most sense.
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I’ve worked in a couple of jurisdictions with rules. In the last one with a common trench and rules, they wanted 6” horizontal separation so we staked to either side of trench. If we went vertical, we would had to have 12” separation.
 
ActionDave said:
I would hate to have to dig below the gas line to get to my conduit if I needed to, I"m sure the gas person would hate to have my conduit in the way if he needed to get to the gas line. Keeping them all at the same depth makes the most sense.
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Exactly, and relative location concerns are just about future ease of access. Having them close (or far apart) and at the same depth makes the most sense. Many come up with "gas +electrical= bad" or "water +electrical= bad" type of thinking, which makes no logical sense. And I hope no one mentions the "not in the same trench" thing😡
 
There is only one Code requirement that I have ever heard of, concerning combined utility trenches, and it’s a Building Code requirement:

If you have sewer AND water in the same trench, AND your sewer pipe is of a slip fit design, like SDR, you must have 5’ of horizontal separation, or 12” of vertical.

This does not even apply to solvent weld piping methods, like PVC or ABS.

I think this is where a lot of the confusion about combined utility trenches comes from. I get asked about this constantly.
 
Seven-Delta-FortyOne said:
I think this is where a lot of the confusion about combined utility trenches comes from. I get asked about this constantly.
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That, and the utility requirements that when a customer installs their gas and electric facilities and hands them over to the utility, the utility has their own requirements about separation for their own access later.

After the point of demarcation, the electric and plumbing and gas codes have nothing to say about it.

We run PVC conduit and PE pipe in the same 6" trench somewhat regularly, and nobody questions it.

We do not make a habit of digging up buried pipes to work on them. We like them to stay where they are.
 
I think you still have to run a tracer with the gas if not epoxied iron. That being the case even though the current carrying wires are traceable. Kinda redundant. Of course they could come up in different places, so the tracer is a good thing.

But you may not be the plumber so let him worry about it.
 
ActionDave said:
I would hate to have to dig below the gas line to get to my conduit if I needed to, I"m sure the gas person would hate to have my conduit in the way if he needed to get to the gas line. Keeping them all at the same depth makes the most sense.
Click to expand...
I would hate to have a gas line in close proximity of conduits in the event some did need to be dug up.
 
National grid requires 6 inch separation of gas from buried electric and 36 inch from water/sewer.
If you are putting it all in the same trench I would make sure marking tape is put into ditch to identify locations of all buried utilities. Gas around here requires tracer wire to be buried with the gas line also.
 
electrofelon said:
Exactly, and relative location concerns are just about future ease of access. Having them close (or far apart) and at the same depth makes the most sense. Many come up with "gas +electrical= bad" or "water +electrical= bad" type of thinking, which makes no logical sense. And I hope no one mentions the "not in the same trench" thing😡
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can dig two separate trenches and still end up with pretty close placement to one another ;);)

and be closer than if you placed them at opposite sides of a single wide trench.

Many haven't wanted phone or coax cables close to electric lines either claiming interference. A they are shielded. B 60 Hz isn't going to cause much for interference.

Warning tape in a trench 12" above what it is warning you about is also just one those things that when you are using a trencher and you see that tape coming out of the ground - it just tells you what you already hit before you do any further excavation to expose it for repairing.
 
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