O.T. - Water pumping issue

I would like to run a scenario by the plumbing-savvy folks on the forum. Sorry for the O.T.

I have a continuously-running waterline which is fed by a spring (siphon / gravity feed). It runs about 1000" downhill and fills a cistern close to my house. I then have a shallow-well pump in the house pumping the water from the cistern to supply my house water needs. This is a fairly common setup around these parts.

Before the water goes into the cistern from the spring site, I have an old tee which used to feed the barn (now cut off and plugged). I would like to unplug that tee and attach a shallow-well pump to it so that I could have water close to the barn again.

My question is: being that most of the water is going into the cistern, would I have enough volume at the tee to use a shallow-well pump and fill a bladder tank? Main line is either a 1" or 1.25", tee-off is a 0.75".

There is a reason I cannot push the water back from the house to the barn (town road in the way). It goes without saying that the pump and bladder tank will be insulated and protected against freezing.

Thanks for any input. It"s getting old to haul water from the roadside.

I have a similar setup for my house without the connection for a barn. Seems as though the one inch line is about as small as the pump manufacturer wants you to go. So I would estimate that the three quarter line is too small for a pump to use. I also suspect that if both pumps were hooked up and run at the same time you could have issues with not enough volume of water. Can the three quarter inch line to the barn just be run as a gravity feed line? might also need a one way valve to keep the house pump from sucking air through the barn run if the barn is left as gravity feed.

Is the cistern full all the time, with an overflow? If so, your plan will probably work. If not, you will end up sucking a lot of air. Better plan would be to pump from the cistern itself, rather than from the inlet pipe.

I would unplug the T and check the volume, if it's not at least 5 gpm you may have a problem. You could but a fairly small pump to match the volume available, if the pump is too large it may suck air from the cistern, it depends on where the T is located in the system.

I use a 3/4 line to feed my shallow well pumps with no problem.

The T is about 40 or 50 feet before the cistern.

The cistern is always full, with a continuous overflow to the roadside. In fact, that's how I always check to make sure the system is running and thatthe siphon did not stop.

The three-quarter line is just a stub about 18" long. I plan to use a 1" line beyond that.

I don't see both pumps interfering with one another. The line going to the cistern and the supply line to the house are not connected.

Gravity feed would not work, not enough pressure, other issues also.

if i'm reading this rite the tee has only gravity flow to it...pumping off gravity flow i think you be suckin more air than water...best thing would be to put another cistern close to barn with a float valve to shut flow off when tank is full...you could also plumb in a manifold so you have extra water reserve you could send down the hill to the other cistern if need be.
then run your pump off tank by barn.

assuming the shallow well pump is centrifugal all you have to do is limit the output and you will have no problem. just use a small line or a valve where your bladder pump is and the pump will be perfectly happy. Some one will probably try to tell you that you will burn out your pump doing this but anyone who has been around gasoline or diesel powered pumps can tell you that the pump doesn't start to load the motor until it is moving some volume of water.

That means the inlet pipe is always full at the T- so you should be able to put a small pump on, to pump to a pressure tank in the barn. But a pump drawing directly out of the cistern would be better.

It sounds like you have positive head at the "T" so the thing that will limit the flow is the pump capacity or or the line losses. As long as the second pump isn"t too big, you shouldn"t have a problem.

Seems to me you're going to need a check valve to keep from sucking back from the cistern.

I got to thinking and I ran across a similar system in the mountains of Arizona once. Down by the road there was a big tank with a float valve and lots of pressure, so I started following the line up the creek valley, came to another tank with valve T-d into the main line, another quarter mile, one more. Probably a total of a mile of pipe and 500 ft of head, that's 220 psi! At the top there was a sand point just shoved down into the creek bottom. This creek did not run all the way down the mountain, the water just disappeared int the ground part way up.

Why do people have to complicate the problem?
Hook it up and try it. The worst thing that could happen is you will have to restrict the out flow to keep it from sucking air. Don't think that will happen.

I'm wondering what do you have at the barn. Another cistern or a stock tank? Seems like you should have enough pressure to push water to the barn. Then use a float valve on the stock tank or cistern.