Hi folks,

Forgive me for needing assistance on such a broad project, but I'm just starting and trying to sort everything out. I'm starting a small vegetable farm and just had a well dug and pump installed (1 hp Grundfos submersible with a 44 gallon tank). I need to run water from it to four locations:

1. Drip irrigation system
2. Small house (130' away)
3. Barn - for a utility sink and an outdoor spigot (150' away)
4. Greenhouse - just for an outdoor spigot (120' away)


They're arranged something like this,



HOUSE
|
|-------GREENHOUSE
|
|
|-------BARN
|
|
WELL----IRRIGATION



I understand that trenches will need to be dug and pipe laid, but what kind and size of pipe would be best and at what depth in the ground does it need to be? From what I've read, I'm thinking 1" PVC at 18" deep would suffice. I'm planning on using copper pipe in the house, so would the PVC come all the way to the house and then change to copper once inside?

I'm also wondering about the fittings right at the tank itself. Would I simply have a single pipe coming off of it and then use T's to direct it other places? I'm not sure what type and size of pipe (I know it was metal) the well pump installer used, but I will get that information soon.


Sorry for my ignorance! Thanks in advance.



Edited 1 times.

since the labor is the same either way, i would just run 1 inch to everything. the material cost is not that much more. i think that the code says you can't use PVC inside a dwelling ? but none of your usage is for dwellings. i would just use PVC for everything reducing to smaller size inside the 'building'..

You need to build a manifold at the tank tee, with tees and 1/4 turn ball valves for each water line. Here in NC you can't have a PVC water line entering the residence , it must transition over to an approved pipe material before entering the foundation. I would use 1" Pex pipe for the runs, there will be no underground couplings like there will be if you use PVC.

The first question to be answered is: where will the pressure tank be located? My pick would be in the house basement where you would have year round protection (freezing, etc.). So, I would install a dedicated line from the well to the house, to the pressure tank manifold.

From there, you would supply water to the house. Then, another line would exit the basement to the barn/greenhouse/irrigation. All three of these supplies must be backflow protected, which you can do in the basement before exit.

I would only consider polyethylene coil pipe for this. It's just too easy compared to everything else. Pipe size depends on gpm demand, but looking at your implied demands, I would guess 1" would be fine (nothing smaller).

Upsizing the tank another two or three sizes would be advised.

Best wishes in your endeavor.



Edited 1 times.

Protection, from the weather and elements. Also protection from backflow, chemicals and grey waters. Also consider potential upgrades, for the future.

Best Wishes

Thanks so much for the information everyone!

North Carolina Plumber:
Should the manifold be above or underground in a valve box?

What's the real advantage of pex over PVC. Is it worth the extra cost?



Edited 2 times.

m&m:

The pressure tank is right next to the well. What's the difference between polyethylene coil pipe and pex? Why would it be better than pvc?

With PVC you will have a connection ( possible opportunity for a leak ) every 20'. If the ground settles under the pipe you'll likely have a cracked pipe to deal with. As I stated earlier PVC is not allowed to enter the structure, you must transition outside the foundation wall, if you happen to get a rock atop the pipe during backfill it'll likely cause a leak at a later time.
Pex or Polyethylene would both be great piping material to use. You can get 500' or more in a roll, that eliminates underground fittings, it's flexible so you don't have to worry about settling, you can run it indoors, etc.
The manifold could be in a box underground near the well, or it could be in the first heated structure you come to when burying the pipe, it all depends on the layout, length of the runs, etc.
If you use Polyethylene, use brass fittings, stainless clamps, and a torque wrench to properly tighten the clamps.
With Pex, I'd go with the polymer fittings and copper crimp rings. Either should give you a lifetime of service.

When you are dealing with hundreds of feet, sizing and pressure are very important to functioning correctly. Determine the demand for each fixture at each location and it is better to oversize the main so that you will have less friction loss and therefore less volume at the fixtures. Take your time make a drawing and show the fixture Unit value of each fixture and knowing the pressure at the tank, you should install a good system. Good luck

NC Plumber, thanks so much, again, for all of the advice. I'm thinking I'll go with 1" polyethylene for the runs, but now I'm just trying to figure out the details of the manifold. As it is now, water will leave the tank, pass a spigot, and then go to a 1-1/4" brass valve with female threads. I'm planning on building the manifold out of 1" PVC like I said, so would it be fine to just connect a taped male threaded 1-1/4" PVC adapter to the brass valve, followed by a 1-1/4"x1" PVC reducer bushing? Then I would connect a bit of 1" pipe and a 90 degree elbow to go underground to where the manifold will be. Does all of this sound like it would be ok?