How to add a 2nd home onto an existing well system

I have recently purchased a 2nd weekend home located on a private lake which has an inadequate well, my neighbor has just drilled a new well which produces 30gpm and has offered to add me to his well for a minimal usage fee. My home is 350 ft away from his well head and 450 ft away from his pressure tank location. I was planning to install new 1"- 160 psi line and need to know whether it would be best to tee off at the well head or on the outlet side of his pressure tank. I want to optimize my pressure, while minimizing pressure fluctuations, to him as well as to myself. Since he is doing this as a "favor" to me, I do not want to change his brand new well system by adding anything that he may not feel comfortable with like a CSV if possible. Which setup will be best for me without impacting his current setup? Do I need a pressure tank as well? Thanks in advance for your help!

You can tee in at the well head as long as he doesn't have a check valve between the well head and pressure tank. If he has a check valve he should remove it anyway. Problems with extra check valves in the sticky at the top of this page.

It will work without a CSV, just not as good!

Lakeman said:

I have recently purchased a 2nd weekend home located on a private lake which has an inadequate well, my neighbor has just drilled a new well which produces 30gpm and has offered to add me to his well for a minimal usage fee. My home is 350 ft away from his well head and 450 ft away from his pressure tank location. I was planning to install new 1"- 160 psi line and need to know whether it would be best to tee off at the well head or on the outlet side of his pressure tank. I want to optimize my pressure, while minimizing pressure fluctuations, to him as well as to myself. Since he is doing this as a "favor" to me, I do not want to change his brand new well system by adding anything that he may not feel comfortable with like a CSV if possible. Which setup will be best for me without impacting his current setup? Do I need a pressure tank as well? Thanks in advance for your help!

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IMO the Tee should be on the outlet side of the pressure tank because if it isn't, water has to flow backwards from the pressure tank to the Tee (and turn the corner into the Tee) every time you use water. Then when the pump comes on, it has to stop that flow and that can cause water hammer which damages plumbing etc..

IMO both of you would benefit from a CSV because his pump has not been sized to provide both houses; especially when both houses are using water. It would be installed before his pressure tank. And you may want a pressure tank with a check valve on its inlet at your house so you don't back feed into his house. Plus that prevents water hammer when he uses water and the pump comes on.

Personally I don't like this shared well thing much unless it was planed from the start of drilling the well (and it is all legal and in writing) but it can be made to work afterward. It's a good fences make good neighbors thingy. It can go wrong in a heartbeat if the two of you, or the extended families don't get along some time in the future; and it can be over the smallest thing or him selling the house, he dies, divorce, costs too much electricity or wear on his pump, etc. etc.. And if you have a larger water use or water treatment is needed, and you get some equipment and he doesn't, you may use more water than he does which can cause a cost sharing problem.

The shared well thing can and often does turn into WW3 in short order. Specially if it goes marginal.

I think you should drill your own well. Its not that what you are proposing won't work, but I would just prefer it if we could avoid WWIII in my lifetime.

In the long run its not worth the savings and will cause both of you problems if either of you go to sell.

-rick

Gary Slusser said:

IMO the Tee should be on the outlet side of the pressure tank because if it isn't, water has to flow backwards from the pressure tank to the Tee (and turn the corner into the Tee) every time you use water. Then when the pump comes on, it has to stop that flow and that can cause water hammer which damages plumbing etc..

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People tee into the well head all the time for other houses, irrigation, barns, etc. It won't cause a water hammer with these small systems, because the water is already flowing that direction when the pump starts. Only a portion of the water from the pump heads to the tank on start up, and the tank can easily balance out the difference.

We have shared wells which were drilled by the developer where I live. The yield of the well determined the number of houses. A 25 gpm well here supplies up to 11 houses. I agree with much that is said above about shared wells. You really need a legal well agreement form and you need easement rights on that well. This will clear up anything that happens should one of you sell. The well agreement is a legal document that states the water is for residential purposes only and that each of you will share all the electrical and maintenance costs. Having someone share the expense of a well is really nice. When I bought my house the lender was very particular about the well so much so I had to get in writing from the well driller that the well was adequate for the number of homes listed. If you do not have legal access to the well you may not be able to sell the house easily.

valveman said:

People tee into the well head all the time for other houses, irrigation, barns, etc. It won't cause a water hammer with these small systems, because the water is already flowing that direction when the pump starts. Only a portion of the water from the pump heads to the tank on start up, and the tank can easily balance out the difference.

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I know they do, mostly because many drillers, plumbers and pump guys say there is no problem in doing it. But it causes water hammer whether they hear it or see evidence of it or not. The water is flowing the opposite direction from the pressure tank to the Tee and that flow is stopped and then reversed. The size of the system is irrelevant, reversing the flow causes water hammer shock between the Tee and the submersible pump. Steel or copper doesn't but PE pipe lets you feel it at the pressure tank.

I've seen guys that have done it then have a huge expense or be told it is impossible (because something has been built over the tee or line) to solve a water quality problem when later they want/need to add water treatment equipment and need treated water at both locations.

You can not get any type of water treatment equipment to work for the other location if it is fed with a Teed off water line before the pressure tank. You would have to duplicate the equipment at both locations or dig up the tee and run the line back to the house on the house side of the pressure tank; or run a whole new line and have sometimes a few hundred feet of dead end water line under the yard. And you can't dig up the tee if anything has been installed/built on top of it.

It is a short cut that can come back to bite those that have that type set up.

Gary Slusser said:

The water is flowing the opposite direction from the pressure tank to the Tee and that flow is stopped and then reversed.
.

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The part about the water going the opposite direction is not exactly true.

If the pump is running and lets say house 1( the owner of the well) is not using any water but house 2 is, and the tank has 40psi ( the well has a 30/50 switch)
House 1 and house 2 will have 40psi, with water flowing to house 2. If the T is at the tank after the pressure switch, where is the water hammer at?

Are not all bladder tank plumbed just this way? The water goes in on the same pipe the water goes out.





Travis



I tend to agree with you on the treatment thing. It would cost twice the money to do it right.

Waterwelldude said:

The part about the water going the opposite direction is not exactly true.

If the pump is running and lets say house 1( the owner of the well) is not using any water but house 2 is, and the tank has 40psi ( the well has a 30/50 switch)
House 1 and house 2 will have 40psi, with water flowing to house 2. If the T is at the tank after the pressure switch, where is the water hammer at?

Are not all bladder tank plumbed just this way? The water goes in on the same pipe the water goes out.

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Of ocurse you're right IF the tee is on the outlet of the pressure tank in the first house but, the OP questioned:

How to add a 2nd home onto an existing well system I have recently purchased a 2nd weekend home which has an inadequate well, my neighbor has just drilled a new well which produces 30gpm and has offered to add me to his well for a minimal usage fee. My home is 350 ft away from his well head and 450 ft away from his pressure tank location. I was planning to install new 1"- 160 psi line and need to know whether it would be best to tee off at the well head or on the outlet side of his pressure tank. I want to optimize my pressure, while minimizing pressure fluctuations, to him as well as to myself.
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My advice was/is against the Tee being at the well head/before the pressure tank. I said for it to be after the pressure tank because of water hammer caused when the direction of water flow to his house is reversed when he is using water and the pump comes on.

Valveman suggested it doesn't matter and there would be no water hammer or problem in a small system like this. I've disagreed.

I haven't mentioned it but with 350 to 450 feet of water line to get water to the OP's house, especially for when both houses are using water during peak demand times, the pressure switch settings are going to have to be higher than the normal 30/50 or 40/60 or the OP's house isn't going to have sufficient flow rates and will be complaining about 'low pressure' and so will the well owner.

So since the pressure switch is at the well owner's house, because the pressure tank is there, his water pressure is going to be rather high. Which will cause more serious water hammer, and higher pressures uses water faster and that will cycle the pump more frequently unless they use a CSV.

BTW, the importance of this is due to all water treatment equipment (and bladder type pressure tanks) has a max operating pressure of 100-125 psi. Repeatedly getting up towards those pressures weakens the resin/mineral tanks and disposable filter housings, control valves etc..

The pressure repeatedly gets up that high if there is water hammer because it can easily quadruple the main line pressure which can exceed that 125 psi max pressure. That's why I have studied water hammer and its causes and effects.

Think Long and hard on this one!!

What do you think your neighbor will say if he has to replace a pump and the bill is $2500.00.

Personaly I would have my own well...

What happens if he has a personal problem and the house sits empty with no electric on....

What if the house burns down...in winter...

There are to many unforseen things that could happen...and may times do...Murphys Law


BTW...who was Murphy?