Pump recommendations for 80' lift from creek (250' run)

[JimLS]

I am wanting to set up a pump to get water from a very small stream. Before anyone jumps in about if this is allowed I have already checked and allowed to do this. The elevation change is about 80 feet on a fairly steep hillside and the run is about 250'. I have guessed about 5 GPM is about all I could reasonably pump from the creek much of the time. The flow is very dependent on recent rainfall, time of the year, etc and it stops completely in late summer on very dry years.

I had thought of putting a pump at the bottom but running wiring is going to be an issue. Burying it on the irregular hillside is not possible (or at least it doesn't seem practical). I could run overhead but would like to avoid that for visual reasons. I could put a gas pump at the bottom but that would require trips down with gas and to start - it would work but getting others to use it would be difficult.

I am thinking of using a deep well pump type setup with the pump at the top where it would be easy to run wiring and running 2 poly pipes to the bottom. I know its not efficient but it still seems like a reasonable solution. I am wanting to get some feedback on this...

I am also thinking I should have some way to adjust the flow for seasonal variations so I don't over pump when levels are low. Could I just put an adjustable valve on the inlet to the venturi to restrict flow when available water is low?

 

[Ballvalve]

If you are going to run 2 pipes, might as well make one 1/2 or 3/4 conduit with 10 or 12 gage wire in it to a 1/2 hp submersible or jet. Not much extra cost in that. Let the grass grow over it. Run it on 2 wires at 240v and pound in a ground rod at the bottom. Do switching at the top.

Use a small pressure tank at the top and a low pressure cut out switch, you cant overpump it then. find a good pick-up design so you are not cleaning it often

 

[Sponsor]

 

[JimLS]

Only one problem with that - it doesn't meet code. Since you say you are an electrician I am surprised you recommend something that is clearly not to code. Conduit with line voltage must be protected. Burial is minimum of 18" as I recall. I think a ground wire is also required but I could be wrong. Given the steep, uneven terrain it would need to be bored which would be expensive. However, I could run extension cords since they are considered temporary and just take them up at the end of the season. Not as good in my opinion but they do meet code as far as I can tell. They would need to be on a GFCI.

Other items - use 240V, pressure tank, etc sound good.

 

[Masterpumpman]

You've got a problem! Meeting code, making it work and doing it right!
Best solution is to install the pump near the stream and install the tank and pressure switch near the demand. Install a low pressure cut off switch or better yet install a cycle sensor http://www.cyclestopvalves.com/products.html#cyclesensor (or equivelent).

A two pipe system to the stream will work but usually works bad at it's best.

 

[Ballvalve]

So I see you are concerned about big brother and his rules.... Big brother permits extension cords but not the same thing inside conduit?? That tells you why I'm not a slave to the "code" - they are pretty stupid. Gonna be a lot of surprised dead possums and rats on that hillside! Or maybe a barbequed guy with a weedwacker. With the GFCI it will just mean more trips down the hill looking for the chewed part.

Notice I said switch it at the top. That reduces power in the line to a short time in a day - maybe midnight if on a timer. Then put in a double pole switch with a commercial quality GFCI feed. GFCI's work without grounds or neutrals.

Finally if you are rule oriented, run an EXTENSION CORD inside the conduit and call it a sun shield. Now you have some extra wires, ground and maybe a neutral that the pump doesnt need, but it meets code and you can leave it all year without feeding the chewing mammals. If they allow cords, I doubt if they have a rule for how long they can lay there.

I think a good quality 3 or 4 wire extension cord will cost you more than the 1/2" conduit with three wires inside. Also remember that those chinese "12 gauge" cords are more like 16 gauge and you might smoke your pump. And to meet code I suspect you need a dedicated 240 volt cord with 4 wires and proper ends. Very pricey.

Anyway, I think breaking code with a partially exposed bit of pvc conduit on a inaccesible hillside is far safer than a rubber cord. I choose common sense over big brothers one size fits all stupidity.