Instead of all the math stuff, I would do it trial and error. That way you know for sure.

McCoy's in Bastrop will be able to order what you need at a reasonable price.

Agneck is a friggin' genius!!!!

Long story on what everyone is telling you.

There is resistance (engineers call this head pressure or head for short) in pipes. As stated above the resistance is 75ft of head pressure for 2" pipe going 4400' horizontal.

You have to overcome the resistance to have any usable pressure at the end of that pipe. If you are using the water for anything that requires pressure to work(i.e. shower head) you will have a problem.

Test you flow (gpm) at the meter if you can using the bucket test. (time to fill the bucket)
http://showerheadmanspeaks.pro/2-minute-bucket-test/.

Test your water pressure at the meter http://www.youtube.com/watch?v=JgxGqQrC6Ds. You will need 50psi for typical home use.
This will give you what you need to check your total pressure loss along the entire length. Use this chart http://www.engineeringtoolbox.com/pressure-loss-plastic-pipes-d_404.html#.UpJF7crnaUk

Your pressure drop along the run cannot be more than the difference.

Ex: 70 psi at the meter - 75psi for 2 inch pipe won't work.

Plan B. Buy bigger pipe (reduces resistance) or add a pump(adds head). Pipe seems easier. you are going to want something 4" or above.

Now the math works.
Ex: 70 psi at the meter - 25 (guess) with 6" pipe = 50 psi.

My $0.02 and I am an engineer.

[This message has been edited by trip (edited 11/24/2013 12:42p).]

So, basically:

quote:

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4,400' is a long way to run spaghetti line. Let me know how that works out for ya...

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Stamped: Pierce County Ag, PE

Never heard head pressure referenced in that manner.

In my world, head is usually the force generated by the weight of the water column - usually measured in PSI. Resistance in pipe is friction loss.

You learn something new every day.

^ You've got it right.

It looks like what the OP needs to do is find out what the minimum GPM and PSI he'd like to have at his house and what the supply side at the meter will allow. I don't know what the standard minimum GPM or PSI are considered for a typical single family dwelling. Only then can you do the math to be sure about what it takes.

I used 5 gpm at 40 psi because that, in my experience, is what I've learned from rural landowners and well drillers as the minimum needed to supply a house from a well. It's not something they would use to water a lawn or anything, they're just glad to have flushing toilets and a working shower. Deerdude mentioned he had 20 psi and he seemed to think that was sufficient.

For future reference could one of the PE's explain the difference in 'ft of pressure' versus 'PSI'. In trip's example it appears he subtracted 75 PSI when early he mentioned the friction loss was 75ft. Are they interchangeable or is there a conversion factor to go from 'ft of pressure' to 'PSI'? It also appears the 75ft of head loss is based on 30 GPM, which might be overkill.

quote:

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As stated above the resistance is 75ft of head pressure for 2" pipe going 4400' horizontal.

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quote:

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Your pressure drop along the run cannot be more than the difference.

Ex: 70 psi at the meter - 75psi for 2 inch pipe won't work.

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Interesting discussion. Thanks.

Stuff like this makes the internet kinda handy:

http://www.freecalc.com/fricfram.htm

"Feet of pressure", to me anyway, would equate to Head Pressure.

Head pressure is the weight of the water column, and you convert it to PSI by multiplying by roughly half. I think the actual number is .42 or .43, can't remember for certain. I generally use .5 so that there is some wiggle room.

So, say you have 100 feet of head. At the very bottom of that water colum, the pressure would be 50 psi, more or less.

Friction loss is the pressure drop due to.....friction. Water moving through a conduit loses pressure because of the friction of the water on the pipe walls, and the water on itself. Various types of conduit have different friction loss coefficients.

A link above has the formula to get whatever answer you want - in GPM or in PSI for the variables you input.

50psi at the house would be the bare minimum for me. 60 to 65 would be preferred, but I like having good water pressure. You can get away with less and do just fine.

Very interesting. I put in 4400' of 2" pvc at 5 GPM and it suggests the pressure loss is about 1.3 PSI. So a 40 PSI supply would be about 38 PSI on the end of 4400', assuming 5 GPM?

Depending on line pressure at the meter in the end I believe it would be less costly to run smaller pipe (2" vs 6") and add a storage tank and pressure pump at the house.

That may very well be the plan SD.

Another advantage to that is poly tanks are relatively inexpensive. You could have several thousand gallons of storage and not have to worry if for some reason the "water supply" was broken or contaminated. With your own generator you could even have water with a power outage.
We used to have this type of set up to provide fresh water to the housing on drilling rigs. Very dependable and pretty bulletproof. The only difference is we hauled water from town as there was no "supply" close like where your meter is.

In order to calculate any friction loss you have to identify your flow rate (GPM) the flow rate is crucial cause it helps determine the velocity of water within a pipe area. The rule of thumb for designing pipe systems is not to exceed 5 ft/s velocity....also known as critical velocity.


in the friction loss chart above, you can see the how the pressure loss increases as flow and therefore velocity increase.

In a design scenerio:
2" Max flow at 5 ft/s = 50 GPM = 1.83 psi loss per 100ft = 80 psi loss at 4400 ft

But at various flows:
5 GPM = .03 psi/100 = 1.32 psi loss at 4400ft
10 GPM = .09 psi/100 = 3.96 psi loss at 4400ft
16 GPM = .22 psi/100 = 9.68 psi loss at 4400ft
20 GPM = .33 psi/100 = 14.52 psi loss at 4400ft
26 GPM = .54 psi/100 = 23.76 psi loss at 4400ft
30 GPM = .71 psi/100 = 31.24 psi loss at 4400ft

...Licensed Irrigator checking in