Separation of buried electrical conduit runs from water, gas, and similar wet lines

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Poindextrous

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Try as I might, I have been unable to find what the required separation is for a buried electrical conduit from both water and gas lines. I'm looking for the required separation when the lines are parallel, and when they cross over each other. In addition, what constitutes a "wet line"? For instance I have both downspout tight lines and perforated pipe French plastic drain lines, do these count as well? I have both those drains and a sewer lines all converging at a corner of a building where I need to also bring down and into the ground both the 2" conduit electrical feed (225 A, 24O V) for a new residence, as well as a copper water line. I'll need to cross them over each other in some fashion to send them to a new residence. Code references, diagrams, and practical advice for when the descriptions don't match reality appreciated.
 
Something that has been argued about for years. But nobody has ever shown me any code to back it up. I say you can put them all together if you want. Water, gas, and electricity all should not be leaking.

Some utilities have rules about distance from their facilities. But that is their own rule.
 
While I agree with Dennis, many POCOs and other utilities have their own requirements which may require certain separation. For example, most require a certain separation between gas and electric. This is due to the difficulty of repairs when they are too close together and it is now recognized by some that it is not safe with gas and electric lies where they may be close or touching in the same trench.
There were some explosions in the recent past in the Baltimore area traced to this. In years past since the local utility (BG&E) was both the electric and gas provider it was common practice to put both in the same trench and is now strictly prohibited. It was determined that that an arcing fault could damage a gas line in close proximity and in some cases lead to leaks years later that migrate into the building..
 
One POCO here requires their trench to be a minimum of 36" for secondary runs. If gas, or water is also in the trench, they require 2' of dirt over their lines, then red caution tape, then any other lines on top of the tape. This doesn't work well for water as it needs to be deep enough not to freeze. 12" is not deep enough. I think that is one way of them saying they rather not have other lines there unless it's dug deeper.
 
Reminds me of the puzzle of drawing lines from each of three utilities to each of three homes, with no lines crossing.
 
There are some good points made: basically there are no separation requirements (unless at the local level) except there may in utility specs for THEIR lines. I don't see that a utility would have any power to say anything about separation for customer own lines beyond the demarcation/service point.

From a future repair standpoint, it may be prudent to not have multiple utilities stacked directly on top of each other.

FWIW I have a water line and USE-2 service conductors run through the same 4-in SDR-35 pipe ( for physical protection).
 
I found this
 

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Thanks for all the feedback. I'll just have to bring this up with AHJ (Authorities Having Jurisdiction for those not hip, like I was, to the jargon.) Our local utility, PG&E, has their service entrance separations spelled out clearly, its just beyond the meter where I'm not finding anything. Separating water supply and sewer makes sense. But if the electrical is all in conduit, and not stacked on top of other pipes to impede their servicing (but by how much?, then it shouldn't be a hazard, unless of course someone gets frisky with a pickax or excavator.
 
For non service entrance applications, some separation is useful to be able to make repairs. The separation IMO is based on if machine dug 18” wide trench or a shovel width.
 
See NESC [Edition 2007]
Section 32 Underground conduit systems
320 Location
B. Separation from other underground installations
3.Sewers, sanitary and storms
4.water lines
5. Gas and other lines that transport flammable material
6.Steam line
However, there is no distance indicated but only behavior recommendations.
 
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