Underground Water Line Size From Welll to House & Barn

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cae0008

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Needing help sizing my underground water line from my well head to my house and barn. My well is 320’ deep with static water level at 100’. Driller recommended setting my submersible pump at 220’. From the well, my barn is 400’ and will have a tee at about 200’ to my house that will be approximately 100’ from the tee. The house will be 4 bed x 4 bath, typical appliances, with lawn irrigation. My barn will not need near the volume of water as the house, just enough for my RV. My question is what size water line should I install? 1”, 1.25”, 1.5” etc? My well pump will like be the Grundfos SQE pump with VFD constant pressure controller. If the drop pipe to submersible pump is either 1” or 1.25”, is there any point in having a larger underground water line? Ive tried researching the science behind all of this but my brain can’t think that deeply so any help would be greatly appreciated. The price between 1.25” PVC and 1.5” is very close so is it worth installing a 1.5” line or will that be unnecessary? Would it be wise to reduce the pipe size from the “tee” to my barn or just keep all of the piping in the system the same size?

Thank You All and please let me know if you need additional information.
 
I’d use all 1.5”. I basically just did a job like yours about a year ago and that’s what we used. It’s on city water with a 1” meter.

If you use pvc, use the metal threaded x pvc socket fittings. Sioux Chief makes them, they’re called “ metal head fittings “
They’re expensive and worth every penny.
 
I’d use all 1.5”. I basically just did a job like yours about a year ago and that’s what we used. It’s on city water with a 1” meter.

If you use pvc, use the metal threaded x pvc socket fittings. Sioux Chief makes them, they’re called “ metal head fittings “
They’re expensive and worth every penny.
Thanks twowax, I suppose there is not a concern with increasing the pipe size after the well? Given my need for water before I build my house, I plan on having the vfd and controller at my well head. Will it be an issue with the pressure sensor being located so far away from the farthest discharge point? If so is the solution to increase the pressure setting at the vfd to overcome the pressure loss due to friction?
 
Thank MicEd. As was said, staying with 1.5" pipe the whole way sounds best. 1" is a little small for that distance, and if 1.5" is not much different price to 1.25", I would go with the larger pipe. With 1.5" there is basically no friction loss. However, friction loss is determined by the GPM being used, and with a CSV or a VFD the flow from the pump is only as much as you are using, not how much the pump can produce. So, basically friction loss should be figure at the largest flow for and irrigation zone, plus about 5 GPM for the house.

The pressure sensor for the SQE or the pressure switch to work with a CSV can both be installed at the well head, as long as that is also within a few inches of the pressure tank. They can also be installed at a distant and remote location where the power comes from as long as the switch/sensor and pressure tank are installed at the same location.

Variable speed pumps are great, and the SQE is one of the best, but they still have their problems. When you start experiencing a pressure fluctuation, loss of water, or just get tired of the cost and aggravation of replacing the computerized electronic CU301 controller, it is easily replaced with a regular/dependable pressure switch and a Cycle Stop Valve. A simple mechanical and long lasting Cycle Stop Valve and regular pressure switch can make the SQ pump work better than with the VFD controller. The SQ pump itself is proving to be fairly long lasting and dependable, it is the CU301 controller that is temperamental and gets expensive. If the installer won't substitute the CU301 controller for a CSV, you can do it yourself when the CU301 fails. Here is how. https://cyclestopvalves.com/pages/vfd-repair-kit
 
Thank MicEd. As was said, staying with 1.5" pipe the whole way sounds best. 1" is a little small for that distance, and if 1.5" is not much different price to 1.25", I would go with the larger pipe. With 1.5" there is basically no friction loss. However, friction loss is determined by the GPM being used, and with a CSV or a VFD the flow from the pump is only as much as you are using, not how much the pump can produce. So, basically friction loss should be figure at the largest flow for and irrigation zone, plus about 5 GPM for the house.

The pressure sensor for the SQE or the pressure switch to work with a CSV can both be installed at the well head, as long as that is also within a few inches of the pressure tank. They can also be installed at a distant and remote location where the power comes from as long as the switch/sensor and pressure tank are installed at the same location.

Variable speed pumps are great, and the SQE is one of the best, but they still have their problems. When you start experiencing a pressure fluctuation, loss of water, or just get tired of the cost and aggravation of replacing the computerized electronic CU301 controller, it is easily replaced with a regular/dependable pressure switch and a Cycle Stop Valve. A simple mechanical and long lasting Cycle Stop Valve and regular pressure switch can make the SQ pump work better than with the VFD controller. The SQ pump itself is proving to be fairly long lasting and dependable, it is the CU301 controller that is temperamental and gets expensive. If the installer won't substitute the CU301 controller for a CSV, you can do it yourself when the CU301 fails. Here is how. https://cyclestopvalves.com/pages/vfd-repair-kit
Thanks Valveman! This is great information!!
 
Thanks twowax, I suppose there is not a concern with increasing the pipe size after the well? Given my need for water before I build my house, I plan on having the vfd and controller at my well head. Will it be an issue with the pressure sensor being located so far away from the farthest discharge point? If so is the solution to increase the pressure setting at the vfd to overcome the pressure loss due to friction?
You could reduce the last 200’ to the barn to 1” if you’re sure you’ll never need much flow there other than a RV hookup.
 
Without much flow you can get stink issues with larger pipe. I doubt it’ll be chlorinated. The section to the house and from the well will be fine as he will be using more water there.

If he does run 1.5” to the barn I would suggest installing multiple outlets so he can max out the flow every now and then.
 
Without much flow you can get stink issues with larger pipe. I doubt it’ll be chlorinated. The section to the house and from the well will be fine as he will be using more water there.

If he does run 1.5” to the barn I would suggest installing multiple outlets so he can max out the flow every now and then.
I just copied your initial response. 🤣
 
I just copied your initial response. 🤣
Yeah I know but I reread the original post where he said the barn will be used for an RV.

I would encourage you to post your own responses rather than parroting other posts.

I try to read the posts throughly but I’m currently running a plumbing business and being a father to two young boys and a husband so sometimes I get distracted.

I’m also a moderator on a professional plumbers forum.
 
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Sorry, I didn't mean to "parrot" your response, but rather agree with your original response and that of Valveman.

Using 1 1/2" all the way makes sense. If the RV is occupied, the line will be used adequately. If the RV is just there and mostly sitting to be used, whether the volume is 8 gallons or 20 gallons sitting in the pipe doesn't really matter in regard to "stink issues" that may occur. And if the RV is just sitting there, purging the line at a goodly flow makes sense, be it 1" or 1 1/2".
 
Low flow doesn’t scrub the line and you’ll get some bacteria growth if you’re too much oversized. Water doesn’t flow in a slug and exchange all the water in the pipe when you run the volume it’s holding.

For example if your pipe holds 8gal and you run 8 gallons of water into a bucket, you didn’t exchange all the water that was in that section of pipe.

This is easily observed when purging the cold water out of a hot water line. The lower the flow the more volume it takes to purge it.

Remember, it’s for the children, it’s for the kids ! 🤣
 
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Low flow doesn’t scrub the line and you’ll get some bacteria growth if you’re too much oversized. Water doesn’t flow in a slug and exchange all the water in the pipe when you run the volume it’s holding.

For example if your pipe holds 8gal and you run 8 gallons of water into a bucket, you didn’t exchange all the water that was in that section of pipe.

This is easily observed when purging the cold water out of a hot water line. The lower the flow the more volume it takes to purge it.

Remember, it’s for the children, it’s for the kids ! 🤣
Perhaps you have forgotten that I am a Registered Professional Engineer. I don't think plumbers take fluid dynamics classes, nor can they perform computations using differential equations to establish flow characteristics of water, let alone other fluids and gases. They generally use tables, charts, and simplified calculations for their needs.

I just reread my response and I didn't see where I said or implied that low flow did scrub the line. But what I did say was, "purging the line at a goodly flow makes sense, be it 1" or 1 1/2"."

I'm scared to death for my grandchildren and great-grandchildren. That's why I'm praying constantly for them and this nation.
 
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Perhaps you have forgotten that I am a Registered Professional Engineer. I don't think plumbers take fluid dynamics classes, nor can they perform computations using differential equations to establish flow characteristics of water, let alone other fluids and gases. They generally use tables, charts, and simplified calculations for their needs.

I just reread my response and I didn't see where I said or implied that low flow did scrub the line. But what I did say was, "purging the line at a goodly flow makes sense, be it 1" or 1 1/2"."

I'm scared to death for my grandchildren and great-grandchildren. That's why I'm praying constantly for them and this nation.
I gave valid reason not to oversize if there are no plans for expansion that would need 1.5” water main. This aged water also isn’t chlorinated which could exacerbate the over sizing and age of the water in the line.

That applies to engineers and plumbers and handymen. 👍
 
Yep, so as the barn is apparently not a farm barn where livestock need water, or else the OP would have said so, then the smaller the line to still provide adequate pressure would be good. And in any case, routinely "purging the line at a goodly flow makes sense" regardless the size.
 
All water lines, especially dead ended lines need to be flushed out occasionally. But I don't worry about stuff growing in underground water lines as much as lines above ground. Underground water lines are cool and out of the sunlight, which helps keep things from growing in the water.
 
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