Water head, pressure, pipe diameter

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Please pardon this multiple newsgroup article. I do not know which newsgroup would be the most-correct. I hang out in talk.origins mostly, so I do not know which hard-science venue would be appropreate for my query. Hydrodynamics does not seem to be represented in the newsgroup list as far as I can tell.
I live and work on a cattle ranch. (Moooo!) We have a fresh-water spring on the side of a hill that produces about ten gallons (38 liters) of water per minute. We want to go up the hill and dig a hole and bury a 55-gallon (208 liter) drum as a collection box and pipe the spring water into the top of the drum; we then want to run a pipe from the bottom of the drum and down the hill into a cabin. (There will also be an over-flow fitting at the top of the drum, but that is not part of my query.)
At the cabin we hope to get around 43 PSI, or about 100 head feet, of water pressure. We plan on using pipe with an inner diameter of 1.5 inches or perhaps 1.0 inches. We do not want to use a water meter / pressure regulator.
The hill's decline is about 20 degrees, but I do not know if that is important to know. As far as I know, what is important is the height of the water source above the water demand (the "head").
My query is:
1) how high up the hill should the collecting drum be?
2) is there a danger of too much pressure if the collecting drum is too high up the hill?
3) is a pressure regulator at the cabin necessary?
I shall appreciate any thoughts and opinions on the subject.
DMR
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100 feet of elevation will give you 43.31 pounds of pressure. 1 foot = .43 psi just multiply feet of elevation cahng time .43 to get pressure you want
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digitalmaster wrote:

Thank you. Is it really that simple? Seems to me even one of our cows could have figured that out.
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I can make it more complicated for you, if you like. Pressure is force per unit area, or the weight of water per unit area. The volume of water in a pipe is V=A*h, where A is the cross-sectional area and h is the height. The density is d, acceleration of gravity g, giving a weight of W=A*h*d*g, and divide by A to get pressure, P=hdg. But d and g are physical constants, the only parameter that you can adjust is h.
So just say 0.43 psi per foot.
No regulator is necessary because the pressure is determined by the height of the tank, and I assume the tank will have a predictable position.
Also, if the pipe is too skinny the pressure will drop when the water is running because of the impedence of the line. I don't know off-hand what you'd get from a one inch ID.
If I were in cow country, I might be worried about drinking water that had been filtered through cow poop. I'll just have to trust that you know what you're doing, but you might want to get the water tested for E. Coli if you think it might be a problem.
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Gregory L. Hansen wrote: [snip]

E. Coli, cryptosporidia, giardia, the fun never ends. Plus, some possible things that may be in the water require either boiling or significant chemicals to get rid of.
They typical way that cattle country folk test the water goes like so. They elect one of their group to try the water. They don't *tell* him he's elected, just fill his canteen with the at-hand liquid. If he remains of acceptable health, the water is declared fit to drink. Socks
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Gregory L. Hansen wrote:

Great! My life is not nearly as complicated as it outta be. :-)

Okay, I will. :-) I have yet to look at the on-demand propane water heater's specifications for water pressure to see what its tolerances are, but at the moment I am considering locating the water source 120 feet above the outlet.

We will probably create our own flat area on the hill to bury the water collection box (55 gallon drum), so the hill will not force us to pick a site we don't want--- unless we hit a boulder. But then we also got some dynamite.

Current water lines on the ranch are 1.5 diameter. I suppose the owners of the ranch will want to keep the same diameter, since there are already tools and spare parts for that size.

I have been force to drink such water when I hiked across the Mojave Desert and then up the length of Death Valley (for fun; no, really). Fortunately the water here is extremely clean: it comes out of rocks and flows into a concrete tank at the spring; the spring and tank are covered with plastic sheeting, plywood, and rocks. Two of the three humans who live here have been drinking it for 11 years.
For 40 years that water used to be transported down to the ranch via cedar logs that had been carved into troughs like a flue; 30 years ago that flue was replaced with hose.
There is another good spring down the canyon a mile that was once flued down to the canyon floor (well, a bench 30 feet above the canyon floor) around 70 years ago. It is located at the base of a cliff wall that rises 1,700 feet. I climb up there now and then to get a drink. :-)

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The propane on-demand heater I've got works with 18' of head fed through a 3/4" garden hose, but not with 16'. I know this because the 55-gal barrel sits on a 16' tower, and the heater doesn't work when the barrel's less than half full.

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snipped-for-privacy@hotmail.com wrote:

Sounds like a good plan to me.
You will get 43PSI at the cabin. The slope of the hill doesn't matter and no regulator is needed.
(I assume the spring is at the same height as the tank will be so no pumping is needed.)
1.5" pipe should be more than big enough. The pipe should be buried deeply to keep heat gain in the pipe to a minimum. Keep in mind that all the water volume in the pipe needs to be drained/used before you receive water at the temp of the tank.
Jim
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1. 100 feet of elevation difference.
2. No
3. No
I presume you will use the barrel as a reservoir with overflow of the excess water. Pipe size depend on the horizontal distance and the desired rate of flow. This data is missing.
SJF
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I did this kinda thing for my mom, back in 1976... geez how time flies:(
Anyhow with a similiar drop and using garden hose we were able to run a sprinkler the kind that goes left and right, for a long time.
in my moms case she had a cistern on the hill, for their home.
I tapped the overflow to a old hot water tank so she could water her garden withourt concern about depleting the water for her house. It worked great till my moved back here and got diovorced.
odd how something that long ago applies here today
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snipped-for-privacy@aol.com wrote:

Yeah, damn few of us are getting younger as the days fly by. :-)

Hummm. I was thinking of a second tank at the cabin but the demand for water probably will not be that great.
Thank you for the reply--- I have added it to my notes to tell the ranch owners.
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SJF wrote:

Thank you. Your answer matched the other reply. Hummm. Why did I not know the answer? 100 feet of head is 100 feet of head, after all. It does not seem it could be that simple.

Yes.
The greatest demand at the cabin will probably be a shower: about 5 gallons a minute at most. Since the hill's incline is about 20 degrees, I can probably use a sine table to find distance. Angle "A" is 20 degrees and side "a" is 100 feet. Makes me wish I finished high school. :-) Horizontal distance at the moment is unknown because I do not know how far away, climbing the hill, will be 100 feet high.
Thank you for your answers. Since the answer to query #2 appears to be "No," then we can err on the side of too high.

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snipped-for-privacy@hotmail.com wrote:

...

The distance that matters is the length of the pipe. One elbow or globe valve has about as much pressure drop as maybe eight feet of straight pipe. Use 3/4, or, to be generous, 1". (Generous means you won't mind someone flushing the toilet while you're taking a shower.)
Jerry
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Sorry! I hastily misread your question 2. The answer is YES. If you put the collector higher than 100 feet, the static pressure will be more than 43 psi.
That's a pretty steep hill at 20 degrees. Or did you mean 20 percent grade? A slope of 20 degrees means the minimum length of your supply line to the house will be 300 feet. For a 20 percent slope, it would be 500 feet. You will probably need something to counter water hammer when you shut off the flow.
SJF
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This is a ranch, man. If there is water hammer, they'll hammer back. 8-)

Remove NOPSAM to email me. Please let me know if you have posted also.
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mm wrote:

Ranch, shmanch. If there's a serious water hammer it can blow a fitting off the pipe. There's more than 300 lb of water in 400' of 1.5" pipe. How fast do you think you can stop it without breaking something?
Stretch in the pipe wall helps considerably. With polyethylene pipe, t can reduce the peak pressure to one quarter, down from the 1000 psi that steel pipe might generate.
There's 37.5 gallons in out hypothetical 400' run of 1.5" pipe, weighing about 300 lb. At 5 gpm, it flows at 100 fpm, or 17 ft/sec or over 5 mph. If you slam a 300lb weight into a cinder-block wall at 5 miles an hour, would you bet that the wall stands? I wouldn't!
Jerry
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Jerry Avins wrote:

There shouldn't be any more problem of water hammer with that set up than with a standard system with long runs of pipe. I was on a community well system (40-60 psi) with a 1/4 mile run to the well for me. Never had a hammer. No difference in flow in the pipe or dynamics of possible water hammer if the pipe is horizontal or vertical, the flow is the same.
Harry K

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Jerry Avins wrote:

There shouldn't be any more problem of water hammer with that set up than with a standard system with long runs of pipe. I was on a community well system (40-60 psi) with a 1/4 mile run to the well for me. Never had a hammer. No difference in flow in the pipe or dynamics of possible water hammer if the pipe is horizontal or vertical, the flow is the same.
Harry K
Actually, in your case, it is the distance from your house to the water main that determines the water hammer. Not the total distance to the supply source. The OP is dealing with a single long pipe which will create a problem unlike the usual suburban situation.
SJF
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SJF wrote:

That was my distance to the system, 1/4 mile of pipe between my house and the well, no other connections.
Harry K
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Harry K wrote:
...

Is there anything else between the house and the well? A pump and storage tank, maybe? At my place, the pump is at the bottom of the well and the pressure tank in the house. No possibility of hammer there.
Jerry
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