Since NEC doesn't "disallow" it, it shouldn't be a problem. We use this common trench set-up often with primary power, secondary power, communications, tv, and gas line all in the same common trench. We use a similar common trench detail that are usually in utility company infrastructure installation manuals, there is usually about a 12" separation between systems. As far as water line, there shouldn't be a problem. Metallic water lines are ground bonded in buildings, and all electric lines underground get wet. Unless the water company or civil engineer in their codes have an issue.
Re: trenches for raceways.#92228 03/09/0504:46 PM03/09/0504:46 PM
If the wiring is before the outside meter, the utility companies should have the say on those trenches. Usually here in NJ the electric/cable and Telco can all go in one trench. Sewer and water in another trench and gas is usually seperate. If the trench in question is on private property and after the utility meter, the all is fair game in the same trench.
Re: trenches for raceways.#92231 03/14/0510:13 PM03/14/0510:13 PM
There's only one safety net, let's say, thay gives us some protection. If the Service Conductors are direct burial, they need a warning ribbon 12" above the conductors. I don't have a copy of the NESC but if the NEC is applicable it would be Article 300 section 300.5(D)(3). I suspect the wording is similar in the NESC.
Re: trenches for raceways.#92232 03/14/0511:29 PM03/14/0511:29 PM
It would be permitted - NEC code wise - to have tel. co and power in same trench...maintaining a 6" clearance(? Article #, anyone..or just a "rule of thumb"?)...BUT water and gas lines usually go DEEPER according to their respective codes and standards. Water is generally below the frost line...don't know about gas. When in doubt, ask the AHJ.
~~ CELTIC ~~ ...-= NJ =-...
Re: trenches for raceways.#92233 03/15/0503:28 AM03/15/0503:28 AM