rbstern
Platinum Member
HDPE is best. Pex isn't designed for outdoor use- don't use it outside! The proper HDPE doesn't need, nor should it have conduit.
I wrote HPDE, but I'm not sure I didn't mean plain old, potable safe polyethylene..
1" at 18" is fine if the frost line is 6". The typical is 1' below frost line and deeper under driveways or other locations where the snow is packed down. The packing tends to drive the frost down.
Don't direct bury low voltage. Put in a 1" conduit.
The conduit and water line can go in the same trench. The typical 1' trench would work fine. HDPE water line at 18" on one side of the trench. Then add 6" soil and place the conduit on the other side of the trench. Then fill trench.
Run a tracer wire with the water line so it can be located before the electrical goes in.
Skip the valve box. Have a shut off on the new line at the well. Go directly into the new building basement and keep the shutoff inside the new basement. No need for an outside shutoff where it freezes.
Key thing here is, if something goes wrong inside the new house, without a nearby shutoff in the yard next to the house, the next place to cut the water is at the tank inside the basement of the existing house. And that house could be locked, which means running and finding the key. The well itself doesn't have a cutoff, and it's another several hundred yards away, and it's covered with a heavy manhole cover (I think there is a switch box for power in there, but I can't recall).
A lot of water could get pumped into the basement of the new house before the water got shut off.
There's a community well house across the street from us, and my neighbor got a feed from them when he built his house a couple of years ago. The well company installed a cutoff valve in a box outside the build site. Hence, my thought of doing the same. It's also what I'm used to for city water setups.
Unless you are having a second electrical meter set the electrical company won't be doing the 240v wiring. An electrician will. It is typical to have all the underground done at once. One tractor is onsite and would dig all the needed trenches and place the needed conduit, water lines etc.
There will be a second meter. Power company will trench and put in a temp power pole at the second home site. Have to meet with one of their engineers to get the specifics of how they'll do it.