River water up 120 ft-Options ?

[aczlan]

I think running a submersible pump dry for any time at all and its toast.

Not sure how you will be running power, but you could use a pressure switch which has a low pressure cutout. Then if it runs dry, the pump will shut off.
The downside is that you will then need to go down and manually reset the pump.
The alternative to walking down and resetting it (assuming that you will have a 220v pump) would be to run 4 "hot" wires down and have 2 with constant power (run through a pressure switch near the pump) and the other two running through a 2 pole momentary on switch. Then if you want to re-start the pump, you hit the momentary on switch to start the pump and get it up to pressure.
See the attached diagram for how it could be done.


Aaron Z

 

[TRR]

To determine pump size:

1 foot of head = 0.43 psi

You would need 120 ft elevation * .43 = 51.6 psi and of course there are friction losses, etc so applying an 80% fudge/safety factor = about 65 psi

If you want the 2500 gallon tank to fill in 24 hours, you're looking at about 2 gallons per minute.

so the pump would have to pump water at 2 gpm at 65 psi.

also, pumps have a maximum suction lift that is typically 25 ft before it can't lift any water (the theoretical max is equivalent to 1 atmosphere which varies but is around 33 feet), usually 10 to 15 feet of suction lift is used.

 

[bcarwell]

Can anyone provide practical experience re deep well "jet" pumps ? Seems like they are cheaper and provide the necessary head possibly at 115 VAC for 110 ft lift with a plus that they don't have a problem maintaining a prime unlike centrifugal or irrigation/sprinkler pumps. And they would avoid the undesirability of "electrifying" the river caused by putting a regular deep well pump in the river with the 115 or 230 VAC line. I'm not sure though if the ejector is less tolerant of particulate matter in the river than a centrifugal or irrigation pump. And the necessity for two lines for a deep well jet pump is not so much of a hassle if the pump is located on the river bank.
Thoughts ? BTW pictures are coming as soon as I can clear the path this weekend as right now all you'd see is brush...

Bob

 

[rambler]

about 120 feet vertical up a 45 degree bank thru 2 inch pvc to a 2500 gallon tank for some cattle water and irrigation. I'll probably use up a tankful a week.

Now, one person suggested 2500 gallons a day pump. You say you want 2500 gallons a week.

I bet the other person is going to be right on your needs, but anyhow, how much water do you want?

Pumping 70 gallons a day can use a real small pump and hose as long as it's pushing water. Could almost go solar on that deal. Tho, when you price solar pumps - you'll nevermind....

If you will need the 2500 gallons per day, then look to the bigger pumps - and a bigger hole to gather water faster - for that flow rate.

Pumps are always more efficient at pushing than pulling water. The jet pumps are a compromise between the two, won't you need 2 pipes running the distance negating some of the savings on wire?

--->Paul

 

[bcarwell]

Paul, I actually realized I could locate the deep well jet pump ("deep" for enough head) at the river bank and thus the two pipes going into the river could be very short, with only one long pipe (going up the hill). As for water usage, I'm watering 10 mini-Herefords plus trying to irrigate 5-8 acres a little to try to get some grass going better. So the cattle water demands per day I'm guessing would be minimal- 50-75 gallons/day. But 2000 gal/5 acres is 400 gal/acre a couple times a week. So no I wouldn't need 2500 gallons a day. But I could probably use it if I'm going beyond 5 acres especially in the Texas summers.

Still wondering about jet pump"ejectors" since I know nothing about them- are they prone to clogging more than, say, a centrifugal or sprinkler pump for example, would a jet pump performance degrade substantially by putting a filter on it for river water (as opposed to cleaner well aquifer water), etc. Does a deep well jet pump develop less head/flow per horse power compared to a centrifugal or sprinkler pump ?