Water Line Run Question

[Kerwin]

I am in the planning stages of running water lines to outbuildings. Starting with a clean slate. Pump pressure tank is in house basement, so all supply lines would originate there. Planning on having running water to three different spots. Longest run would be about 210 feet from house.

What are the pros and cons of running individual lines (3/4 inch black poly) to each of the three water sites, rather than one main line with branches? Lines would be in the same trench as much as possible, but would branch out as needed. All three could probably run together for about 80 feet before the first branch, then two could be together for another 100 before they would split apart.

My initial thought is that by using individual lines I could avoid underground connections and be able to shutoff and drain the individual lines as needed. Also, a leak in one line would not bring down the whole system. The runs aren"t that long so the overall cost of the black poly is not too bad with running them separate.
 

[Two Dogs]

Looks like you've talked yourself into a good plan. Maybe go one inch on the longest run. TDF
 

[rustyfarmall]

I would use 1 inch for all of it.
 

[OliLt]

For optimum pressure and gpm"s, I would run a 1.25"-1.50" main line with branches off from that. A lot will depend on your pump capacity, how many lines would be running at the same time, and what you want for pressure and gpm"s at the working end. There are formula"s to calculate these values if you want to do a Google search.
 

[mosinee dave]

Go with intivituall runs like you say you can shut one off and not effect the rest. if you have rocks I put it in small drainage tile the extra money is worth the pain if you back fill a rock on it. Also use brass connecters I found out the hard hay after a few years I had a couple either pull out or break also double strap them with stainless steel hose connecter.When we were digging them up to fix my contactor was jacking me up on these issues.
 

[wisbaker]

You hit the advantages on the head, the disadvantages, more friction, less flow, more KW needed to run the pump at the higher head pressure.
 

[David G]

I would go no less than 1" on any of the runs. A smaller line is easier to break.
 

[George Marsh]

Kerwin,
Why would you want to drain lines? My frost line is 24 inches. My water lines are installed 36+ inches below grade. I never drain my lines.

Without knowing what the lay out of your plans are, it's hard to say what will work best for you.

Going out on a limb and say your pump is in the well, tank is in basement and the line from the pump is 1 inch. I have the same set up. I installed a hydrant 150 ft from tank with 3/4 inch plastic. No problems, plenty of water. I have a hydrant at the well head too. Lots of water there too. I have a hose bib at house. I can run all 3 and have plenty of water. Just how good is your well? If your well can't put out lots of water, why use large pipe?

Would it save you trenching and pipe if you teed in at the well head? You don't have to go to the basement to run lines.

Do you plan to have all three hydrants going at the same time? If you do, can your pump handle all 3 at once? If it can't then what is the advantage of 3 different lines? Will you have to dig up more of your yard to run 3 lines? Will you save trenching running a main and having 3 branches?

I wouldn't use a pipe bigger than the pipe from your well to the house.

There is a lot you are not telling us. Guess there is no real simple answer.

George
 

[4010guy]

3/4 i feel is plenty and just t off..
I got a line buried for over a mile to a cattle tank thats a 1/2 inch...
I shure theres others that will say dif so do what u feel good about
 

[Dick L]

All of my under ground lines here at home are one inch. I used two inch at the factory underground the 150 feet from the well to the tank and then one inch inside just below the the rafters. I ran two inch from the system pump to the machines and one and one half to the coolers and manifolds. A lot of friction from water running thru pipe. All depends on the volume you expect at the use end. Myself I hate standing with my leggs crossed in the cold waitiing for a pail or tank to fill.
 

[MarkB_MI]

Go big.

210 feet is much too far for 3/4. One inch is a minimum, and I don't think two inch is out of line. By running a big, single line, you'll get full pressure to all your outbuildings, all the time. You'll get the same pressure drop from 200 feet of two inch pipe as you would get from 15 feet of 3/4. And I would use one inch for all the branch lines.

Bury your lines deep, and use frost-proof yard hydrants inside the outbuildings. 3/4 inch hydrants will be just fine, since there will be much more pressure drop in the one inch branch lines than in the hydrants.
 

[MarkB_MI]

"I wouldn't use a pipe bigger than the pipe from your well to the house."

George, let me give you a quick course in fluids. Pressure drop in a pipe is proportional to its length, and inversely proportional to its cross sectional area. What's that mean? In your case you say you have 150 feet of 3/4 inch pipe to your hydrant. And you have 10 feet of 1 inch line from your pump to your house. 3/4 pipe has .56 times the cross sectional area of one inch (.75 squared is .56). So that means you have 27 times the pressure drop from your house to your hydrant as you have from the pump to your house. (distance ratio is 15, divided by the area ratio of .56).

Now if you have a marginal pump, you won't notice that difference because the pump can't flow enough water to generate much pressure drop. But if you own a Miracle Wonder Pump like you say you do, you're cheating yourself by undersizing the plumbing.
 

[Brian G. NY]

Back in "96 (long before I had access to all the information available on this site) I ran a water line to a frost-proof hydrant at my pole building 220 feet from my water pump at the house.
I used 3/4" black poly and I have sufficient voulme and pressure for my needs.
Had I had access to this site back then, would I have used 1"? Probably, as the cost difference is negligible. I personally like the idea of separate lines!
BTW, my line is buried 5" to 6" deep and I do not concern myself with either draining or freezing.
 

[Justin SE IOWA]

I work in the water industry and you have the right idea. Run a seperate line to each hydrant and run 1" 200PSI. Anything less than 200PSI is thin wall pipe and it will leak. I see it once a week! Also stay away from barb fittings underground. USe a good compression fitting.
 

[George Marsh]

Mark,
There isn't enough pressue difference at 150 ft to notice. I can run a total of 5 sprinklers, 2 from hydrant, 2 from well head and one off the house all at the same time. If there was a pressue difference don't you think the sprinklers would show it? They don't. Still have 35 psi at the house. Each sprinkler covers 3000 square feet. At the 150 ft hydrant I have two 3/4 inch 75 ft hoses going to each sprinkler. How do you explain that?

BTW, well was installed a few month's ago.

George