main line size

[jwh1]

Our well is 700 ft from the house and 15 ft higher then the house. What size of line do we need? We are considering 1 1/4 inch. We are concerned about the line loss over this distance. Would 1 1/2 inch make a big difference?

[markParticipant]

Size of line and distance from your house will in no way be a concern for major losses. The line entering the house should not be more than 1/4inch larger than the line in the house.Imagine having a 1-3/4inch pipe flowing full speed ahead to your house from your well. Then imagine all that water trying to fit into the 1/4inch pipe inside your house.The force behind the water must go somewhere; that somewhere is your piping network. This will cause unwanted stress on your pipe joints. A flow regulator could be installed to reduce this stress, however this would be working against your pump and is very inefficient.Just so you know most service lines to homes are 1/2inch and even 1/4inch. I would go with 1/2inch if you are doing any irrigation and never less than 1/4inch. Any size bigger than 3/4inch is most likely too much for normal water needs.The one and only important number we must know here is how high must the pump lift the water. Add up the total height the water moves from the inlet (water level in well) to the outlet (highest tap). Your pump MUST be rated slightly higher than this total height.The pump manufacturer should be able to provide you with information to determine what pump size best suites your needs. All you need to show them is the height you added up.

[markParticipant]

Mark, I think Corbin has mis-written something here…I cant figure out what hes getting at. He may be back later to correct his pipe sizes.I dont know anything about pumps, etc. But house service lines are never smaller than 3/4 inch anymore. And 1 1/4 from the well sounds like a minimum. Ill be back later for a longer response if Corbin or someone else doesnt answer your question. Don

[markParticipant]

Mark, I was hoping someone else would have already answered your question. It is an easy one for a person who works on wells, which I dont. My plumbing code book has sizing charts but each chart starts with the size of a water meter, and you dont have one. So Im at a loss. There are several things needed to use the charts: Minimum normal water pressure, water meter size, building supply pipe size, elevation difference, and distance to farthest fixture.A one inch meter, 30-45 psi, 1 1/4 inch building supply, 700 feet, will allow 12 fixture units.When the chart changes to 1 1/2 inch meter and building supply, 30-45 psi, 700 feet, will allow 23 fixture units.So in this example, when pipes go from 1 1/4 to 1 1/2 inch, supply quantity almost doubles.I know this doesnt completely answer your question, but maybe it will help you make up your mind what size pipe to use.If you need more info, maybe you can ask at the following site, they sometimes have water well people hanging around…http://www.plbg.com/cgi-bin/forum.pl

[markParticipant]

DonI assisted in installing the following network and many others like it while employed for South East Kelowna Irrigation District, Kelowna, BC, Canada.This system was designed for an area that consists of 5 tree farms. A gravity feed system with a network of PRV valves (about 120 psi down to 60 psi).A 12inch insulated steel main line ran down to the housing district and was about 3/4 of a mile from the house we were employed to install new services to.From this mainline 4inch C900 PVC enters a pressure reducing station.From the PRV station the 4inch carries water through 3 different properties all having at least 10acres of irrigated land (6 services). The line ends at the end of the last property and has been designed to support more homes.Branching from the mainline and entering each property was one 3/4 inch service for irrigation and one 1/2inch service for the home. Each of these lines had a meter placed in line.I was also suprised and asked the designer about his choice of pipe size. He responded that previous to 1994 all irrigation services were 1-1/4inch and services to homes were 3/4inch.Through management changeovers money was to be saved and smaller pipe sizes used.Irrigation sizes changed to 3/4 or 1inch and service to homes was moved to 1/2inch for large homes and 1/4inch for small condos, trailers and apartments.This system works very well and is inplace with plans for extension to 3 other farms.I am sure that a pump which could produce sufficient pressure (60psi) on one of the upper level faucets would not need a line bigger than 3/4inch. However, since this system is drawn from a well and is without a separate irrigation service a larger line may be needed for irrigation.If daily long durations of irrigation are required a line of about 1-1/4 to 1-1/2inch would definately be adequate for a well system.Remember if irrigating from the same line as home service is on always have a proper backflow device installed.It is best to avoid this and install two services (only for networked systems).

[markParticipant]

We might be getting off the track here at Marks expense…but Don is correct and Corbin is in left field. To make a statement think about water flowing from a 1 1/4 pipe trying to fit into a 3/4 pipe is absurd to say the least. Breaking pipe joints, I dont think so! The most water that will flow thru this line is what the area will allow at a given pressure, (whatever that happens to be) period. Remember the pipe wall itself is a restriction to flow, the larger the dia. the less restriction. However head pressure is your greatest concern. But volume is directly connectly pipe dia. and will be noticed by that person taking the hot shower on the second floor when the washer is running in the basement!: Don: I assisted in installing the following network and many others like it while employed for South East Kelowna Irrigation District, Kelowna, BC, Canada.: This system was designed for an area that consists of 5 tree farms. A gravity feed system with a network of PRV valves (about 120 psi down to 60 psi).: A 12inch insulated steel main line ran down to the housing district and was about 3/4 of a mile from the house we were employed to install new services to.: From this mainline 4inch C900 PVC enters a pressure reducing station.: From the PRV station the 4inch carries water through 3 different properties all having at least 10acres of irrigated land (6 services). The line ends at the end of the last property and has been designed to support more homes.: Branching from the mainline and entering each property was one 3/4 inch service for irrigation and one 1/2inch service for the home. Each of these lines had a meter placed in line.: I was also suprised and asked the designer about his choice of pipe size. He responded that previous to 1994 all irrigation services were 1-1/4inch and services to homes were 3/4inch.: Through management changeovers money was to be saved and smaller pipe sizes used.: Irrigation sizes changed to 3/4 or 1inch and service to homes was moved to 1/2inch for large homes and 1/4inch for small condos, trailers and apartments.: This system works very well and is inplace with plans for extension to 3 other farms.: I am sure that a pump which could produce sufficient pressure (60psi) on one of the upper level faucets would not need a line bigger than 3/4inch. However, since this system is drawn from a well and is without a separate irrigation service a larger line may be needed for irrigation.: If daily long durations of irrigation are required a line of about 1-1/4 to 1-1/2inch would definately be adequate for a well system.: Remember if irrigating from the same line as home service is on always have a proper backflow device installed.: It is best to avoid this and install two services (only for networked systems).

[markParticipant]

Corbin, Thanks for the info, it is very interesting. I will reread it several more times later. Here in Texas, and most of the US, 3/4 inch is the minimum pipe size for a residential service. A 1/2 inch pipe can supply only a maximum of three plumbing fixtures inside a house. And 1/4 inch can only be used for the very short distance between a cut-off valve below a sink up to its faucet. Even our cheap garden hoses are 3/8 to 1/2 inch. A good rubber hose is 3/4 inch.These things make me wonder if 1/4 inch in Canada is the same as 1/4 inch in the US. And I wonder if those houses you spoke of had very minimum in the way of plumbing fixtures. I wouldnt think they could have two or more bathrooms as is the norm here. Thanks again for the reply. Don

[markParticipant]

TedI know what your thinking, but its wrong. I saw the design and operation of service lines this size in a network that served over 25 000 people. Not only were the designs very economical, proffessional and accurate, they were also designed by people with more education than me and you put together.In one sentance you say The most water that will flow through this line is what the area will allow at a given pressure. This works to prove my point and half of yours. The real proof behind what I say is: Flow = area x velocity What the area will allow is what velocity and flow will give when a line is running full at a fixed speed.A large change in pipe diameter will increase pressure on the point of diameter change and possibly more if the network is weak. This is a basic flow priciple for any incompressible liquid. Any hydraulic engineer would learn this in their first week. The proof is: Flow = Velocity1 x Area1 = Velocity2 x Area2 The 1 and 2 represent velocities and areas of two different pipe sizes.When one pipe diameter changes the flow is limited by that change. So when area changes, velocity and flow change. Velocity will increase therefor pressure will increase and flow will remain the same.Now put your numbers into this equation. See what the pressure change from a 2inch line to a 1/4inch line is. Now try it for a 12inch line to a 1inch line. Is this increased pressure necessary for a single family dwelling or is the differance so small that there is no point. Try it, I have.I hope you see my point. Although your approach is great in a Tim the Toolman, more power to ya type of way, it often results in oversized lines and wasted resources.Unless the pump can not overcome the head to provide adequate pressure for multiple open outlets (it should if sized properly) a change of line size from outside to inside is completely unnecessary.

[markParticipant]

This is great! I wish I was smart enough to continue the conversation…But I cant quite understand it all and dont have the time to think about it right now.tedbo, youre right about one thing for sure, we are no longer helping mark.Corbin, you may be absolutely right in everything you say but Im not smart enough to understand your logic…And it seems somehow contrary to what I believe I understand.Mark and other readers, all US plumbing codes that I am aware of do not allow water service lines to residences smaller than 3/4 inch. So 1/2 and 1/4 inch water service lines (as discussed here) would actually be illegal in most states. I look forward to a time when this topic comes up again. Don

[markParticipant]

I am unaware of any and all US plumbing codes. I am from BC, Canada. I know most common practices in use in Canada today. I would expect that the codes in each of our countries would have great similarities and differances.I do know the last thing Ted said earlier is true. In Canada there is no way anyone in a home can have a shower while any other faucet is running. The change in flow would burn or freeze your ass off. Homes are designed to allow about only 2 outlets open at a steady pressure. After that the pressure drops off.I have a feeling by what everone is saying here that this pressure change is not common in the US. It seems water supply to US homes is based on the most you can get to each outlet if they were open all the time all at once.In Canada we have 98% of the worlds fresh water and our government is dead set on keeping it this way. Smaller lines are used for conservation of water and irrigation of non agricultural properties is strictly managaed in the summer.Maybe the US should look to follow California and stop using their water like it was as plentiful as air. California will have no water in the near future and they will either get it from the ocean or Canada.The proof (calculations) behind what I said last time is listed in Water and Waste Water Technology by Mark J. Hammer. This book is very indepth and I reccomend it as basic knowledge to anyone in the water or waste water business. By the way thiks book is published in the US and should be available.

[markParticipant]

Corbin, I think you have cleared up much of the apparent disagreement. We in the US want to be able to use multiple fixtures at the same time without noticable pressure loss. And we are wasteful…But that is slowly changing. I wouldnt be surprise if some day we move in the direction that you have been describing to us. Thanks for giving your time to help others. This internet sure makes the world smaller. Don

[markParticipant]

Corbin, You can quote any engineer you would like! Ive been working around them for 30 years on all areas of fluid transfer field… and Ive been correcting their prints & P&IDs all along too. I especially enjoy the ones who say Pipe it up and Ill come out to check it, what they really meant is theyll draw it up after youve installed it! At least thay dont waste my time having to run back to them through out a project seeking approvals for corrections.I stand by my original statements, and Ill remind you of yours, quote…. Imagine having a 1-3/4inch pipe flowing full speed ahead to your house from your well. Then imagine all that water trying to fit into the 1/4inch pipe inside your house. The force behind the water must go somewhere; that somewhere is your piping network. This will cause unwanted stress on your pipe joints. end of quote…..Maybe you would like to re-think or re-state this statement. But you should understand that the amount of water which will be flowing full speed ahead thru the 1 3/4 pipe will be the same quantity as is flowing thru the � line only at a much slower rate. In fact this full speed ahead you speak of will probably be slower than all ahead 1/3.You see, pressure in a piping is exerted equally in all directions (except for the velocity of the mass when it is in motion. It is only in motion when it is seeking the point of least resistance (i.e. an opening in the piping system) That � pipe can only accept a limited amount of water provided by larger pipe at a given pump pressure, (not taking in to account the velocity because there is none to speak of, in the larger pipe considering the vastly different pipe sizes.: Corbin, : I think you have cleared up much of the apparent disagreement. : We in the US want to be able to use multiple fixtures at the same time without noticable pressure loss. And we are wasteful…But that is slowly changing. I wouldnt be surprise if some day we move in the direction that you have been describing to us. : Thanks for giving your time to help others. : This internet sure makes the world smaller. : Don

[markParticipant]

You may be right but I dont think you know what I meant in the first place.Your multiple force theory is interesting to say the least. If it is true then why in the hell do thrust blocks get placed on all large 90 degree elbows. If you want me to get out my little textbook I can prove you wrong with basic Vector Kinematics.It is one thing to know how to plumb a system. It is another thing to know why you plumb the system the way you do. You know how, I know why. The mathematical relationships I refer to are in no way your or my place to dispute. These equations were derived by men who have won nobel prizes and revolutionized the hydraulic engineering world. You or me have no right to dispute these findings.By the way, why is it you waste your time complaining about a mistake I made? Youre here to answer questions. I havent seen very many responses from you. From a guy so eager to dispute everthing I would expect more answering and less BS.Prove you know so much, answer some ?????s.

[markParticipant]

: Our well is 700 ft from the house and 15 ft : higher then the house. What size of line do we need? We are considering 1 1/4 inch. We are concerned about the line loss over this distance. Would 1 1/2 inch make a big difference?

[markParticipant]

Mark Looks like you created some interesting reading but I would assume you are pretty confused right now. I am a certified well driller and pump installer and have been doing that for 20 years. It is fact that the only consideration for pumping water horizontaly is friction loss in the pipe. It is fact that at any given flow through a given diameter pipe will have friction loss. The greater the flow of water the greater the friction loss. Also the smaller the pipe the greater the friction loss. If the pressure tank is in the house that friction loss will add to the amount of head pressure the pump will pump against and the pump will need to be sized acordingly. Also the amount of pressure the pipe at the well end has to deal with increases. If the pressure tank is by the well 700 feet away from the house you will notice that the pressure can drop considerably by the time it gets to the house. And again this amount of pressure drop will increase the more water you use. There are charts available that will show how much pressure drop for what size pipe and what flow of water. I could E-mail you some.As for being hard on the pipes… It is fact that if flow was to remain the same and we made the pipe smaller the velocity (Speed of water travel) through the pipe will increase. Then when the valve at the discharge end shuts the water will hammer against the valve. Momentum of the water will for a moment create extra pressure against the valve. The greater the waterflow the higher the pressure. the slower the water flow the less pressure you will have. In a larger diamater pipe the velocity drops (so does the water hammer). Pipe manufacturers will definately back me on this and Ive personaly heard many of them say the same thing. As far as alot af water rushing through a pipe and then hitting a drop in pipe size, it wont happen The water going into one end has to equal the water going out the other.I dont know what kind of flow you need at the house but an average home I would run 11/2 pipe for that distance because I can lay that for the same cost as one inch. One inch will get you water but there will be sacrifices to make. 11/4 pipe might be good enough. Again I dont know what you peek demand will be at the house.Good Luck Ray: Our well is 700 ft from the house and 15 ft : higher then the house. What size of line do we need? We are considering 1 1/4 inch. We are concerned about the line loss over this distance. Would 1 1/2 inch make a big difference?

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