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Default Water head, pressure, pipe diameter

Gregory L. Hansen wrote:

In article .com,
wrote:


Thank you. Is it really that simple? Seems to me even one of our cows
could have figured that out.


I can make it more complicated for you, if you like.


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

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.


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.

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.


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.

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.


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.

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.


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. :-)

--
"In any case, don't stress too much--cortisol inhibits muscular
hypertrophy. " -- Eric Dodd