Bore Holes And Sub Pumps

[waterworks]

Hey the TVers....

could somebody, please(!), advise with the relevant technical know-how (indepth knowledge please, not just "I done it this way once and it worked.....") on the following scenario:

130m deep borehole

6" bore

what pump should I be using (how many HP? flow rate? etc.... as many specs as possible, please?)

what diameter should the pump be? (surely the same (okay, a few mills. less) than the bore, right?

any advice or experiences with particular models? Brands? etc.....

living on Koh Lanta, red mud......... SOME dodgy, "khee gong" locals...... spewing forth some crazy figures and facts!?!

thanking anyone in advance for your help

all the best

Chris

[Rinrada]

www.thaivisa.com/forum/Boreholes-t81390.html

We probabally have the worlds best experts on the subject...see above....only thing we ever seem to disagree on is the costs....you can get ripped off so do your homework.......

I have been quoted 40K to 180 K for mine but still thinking about it .

In the meantime I got the lads with their excavators in and build a dam instead....temp of course...

[Lite Beer]

http://www.thaivisa.com/forum/Boreholes-t81390.html

[Boksida]

Hey the TVers....

could somebody, please(!), advise with the relevant technical know-how (indepth knowledge please, not just "I done it this way once and it worked.....") on the following scenario:

130m deep borehole

6" bore

what pump should I be using (how many HP? flow rate? etc.... as many specs as possible, please?)

what diameter should the pump be? (surely the same (okay, a few mills. less) than the bore, right?

any advice or experiences with particular models? Brands? etc.....

living on Koh Lanta, red mud......... SOME dodgy, "khee gong" locals...... spewing forth some crazy figures and facts!?!

thanking anyone in advance for your help

all the best

Chris

Waterworks,

I can send you specs on a pump but need to know a couple of things first:

1. How much water do you need? No point in getting too large a pump as it will cost extra in electricity bills with no gain.

2. Has any testing been done on your well? Casing size is no guarantee of yield. You should at least know what the static water level is and, hopefully, pumping water level at a specified rate.

3. What is the internal diameter of your well casing? Some nominal 6" diameter pumps will not fit in 6" heavy wall casing. If you can use a 4" or 5" pump you will have fewer future maintenance problems.

4. Is your casing PVC or steel? Is the well cased to total depth? If so, what type of screen or slotted pipe was used in the entrance area and at what depth is it? It is common to use a smaller diameter screen than well casing - has this been done in your well?

5. What surface equipment or lift do you have that could add to pressure requirements?

4" submersible pumps are available at hardware stores nationwide and occasionally 6" pumps as well. Don't go cheap on your pump column pipe as you will regret it later.

If you can post some more information I can probably send you a .pdf file with pump specifications or direct you to a suitable website.

[Beardog]

Along with what Boksida mentioned he is 100% correct!

Do not go for the cheap Charlie off brand pump you will regret the poor decision later if you do & realistically you wont save that much on a cheaper brand after you have to replace the pump & have water delivered to you while you wait for it to be repaired!

Is the 130 meters deep due to the salinity of the water? seems to be way deep for a bore hole. especially being at near zero altitude or you up on a hillside?

Edited July 7, 2008 by Beardog

[waterworks]

Cheers alot everyone, sorry for delay but been of to good ol' KL...

Boksida, and others....

here's some more facts....

It's a long story.... drilled to 130m last September.... we had the temporary electric for construction installed. This wouldn't provide enough power to a pump at 130m says waterman and so we'll stick it at 50m till you get proper electric put in.... then we'll bring in a nice new shiny badboy pump from Italy and drop that down all the way.

Seemed feasible so went with it....

A little while back, we got mains electric and they came and went while I wasn't here (about a month ago or so...) under the "watchful eye" of my site "foreman"..... who saw absolutely nothing :D

It worked for a while - slowly..... hardly filling the tanks at a rate that taps fill a bath at........(!)

then it rained hard.... they hadn't closed off the lid and we got a red shower in the morning! We started ordering our water to be delivered....

Last week "repair man" comes and I establish that he pulls a 1.5HP pump up from only 60m!! (Did I say "Khee Gong" in my first post?)

It's broke.... the impeller..... which (thanks to MaizeFarmer's fantastic post) leads me to believe that stones got in it because I'm totally clueless as to what was being used on the initial drilling day last year... there was definitely alot of muddy water going in and around the drill on it's way down..... so that's slurry?

That brings us upto today but before that, you asked for some facts, Boksida......

"how much do I need" -

got two bed, two bath house, 4x3m pool (topping up, maybe, a coupla cm every 2/3 days.... 250l or so?) little bit of daily spraying a 20m x 35m garden etc..... we've already got 1600l tank, which, as far as I am concerned, will more than suffice SO LONG AS the sub pump can top it up fast enough at peak times! in all you TVers' experiences, should I be hoping for 1,500-2000l per hour?

hoping to build another two houses (maybe bigger) onto the same system in the future, which could drive demand at peak times up to around 6000'ish litres per hour.... (maybe?)

boring company supplied no facts..... no testing results were supplied to me on the initial bore - no static or pumping water levels supplied...

borehole is cased with 6" PVC pipes glued together to total depth, they "say"......

I believe that I am staring at a 6" PVC pipe at the top of the bore and so seemingly a screen has been "misplaced"

"surface equipment or lift" ? Not sure what these could be but we're pumping direct from subpump into the main tanks

sub pump is 4" Franklin (so SHOULD be trustworthy, right?)

So then - they were back today with a new impeller and pump unit, both 1.5HP (is this a pathetically small amount of power to be moving such a heavy column of water from such depth?) dropped the new pump down to a newer lower level of 100m....

It pumped at what seemed like a beautifully ferocious rate flooding the corner of my garden with rich red water (they claim they've spilt mud in....... I'm skeptical......).....

Then they stuck the giant (brass?) valve ontop of the borehole lid to stop water leaking back from the tanks... (shouldn't that be on the tanks?) and dropped the pump all the way down to 120m..... upon turning on the pump again we got only about half the flow rate (visually) than previously!

so the water continued flow slowly and to clear a little bit over the next hour but is still cloudy..... they say it's too heavy to lift the system now it's so long and so they're coming back tomorrow..... with heavy lifting gear!

This company do all the big local hotels and seemingly have a fairly good rep for supplying to meet expectations - but I still can't help but smell something highly fishy going on...

Hopefully these facts will help someone to supply me with some more positive points?

I guess this looooooong post could be summed up very easily.....

What should a 1.5HP pump at 120m depth supply as a flow rate in an area where the vast majority suffice with a mere 40/50m? And, yes, I am about 40m above sea level on gently sloping hillside...

Cheers alot forumers.... your eyes are probably bleeding now...... my hands are certainly hurting......

All the best

Chris

[Boksida]

Cheers alot everyone, sorry for delay but been of to good ol' KL...

Boksida, and others....

here's some more facts....

It's a long story.... drilled to 130m last September.... we had the temporary electric for construction installed. This wouldn't provide enough power to a pump at 130m says waterman and so we'll stick it at 50m till you get proper electric put in.... then we'll bring in a nice new shiny badboy pump from Italy and drop that down all the way.

Probably a Lowara or Calpeda brand - both acceptable quality

Seemed feasible so went with it....

A little while back, we got mains electric and they came and went while I wasn't here (about a month ago or so...) under the "watchful eye" of my site "foreman"..... who saw absolutely nothing

It worked for a while - slowly..... hardly filling the tanks at a rate that taps fill a bath at........(!)

then it rained hard.... they hadn't closed off the lid and we got a red shower in the morning! We started ordering our water to be delivered....

Last week "repair man" comes and I establish that he pulls a 1.5HP pump up from only 60m!! (Did I say "Khee Gong" in my first post?)

It's broke.... the impeller..... which (thanks to MaizeFarmer's fantastic post) leads me to believe that stones got in it because I'm totally clueless as to what was being used on the initial drilling day last year... there was definitely alot of muddy water going in and around the drill on it's way down..... so that's slurry?

Drilling with mud should not be a problem if the well was cleaned out properly afterwards. This is called well development and the locally used term is "pattana bore". Either your well has not been developed or the ingress area has not been screened. Both of these are also possible. Can any one on site tell you if an air compressor was used after the casing was installed to clean water out of the well? This would have been noisy, and possibly spectacular, so it should have been noticed. Air is used to remove solids etc. so a pump will not be damaged.

That brings us upto today but before that, you asked for some facts, Boksida......

"how much do I need" -

got two bed, two bath house, 4x3m pool (topping up, maybe, a coupla cm every 2/3 days.... 250l or so?) little bit of daily spraying a 20m x 35m garden etc..... we've already got 1600l tank, which, as far as I am concerned, will more than suffice SO LONG AS the sub pump can top it up fast enough at peak times! in all you TVers' experiences, should I be hoping for 1,500-2000l per hour?

hoping to build another two houses (maybe bigger) onto the same system in the future, which could drive demand at peak times up to around 6000'ish litres per hour.... (maybe?)

Is getting three phase power later on a possibility?

boring company supplied no facts..... no testing results were supplied to me on the initial bore - no static or pumping water levels supplied...

A reputable contractor should be able to supply you with a simple "as built" diagram.

On one of their future visits can you ask then to measure water levels. This is done with a reel of electrical cable which works pretty much like an ohm meter. Once the sounder hits the water, a circuit is made giving a visible signal at the surface. Every drilling contractor/pump installer should have one.

borehole is cased with 6" PVC pipes glued together to total depth, they "say"......

I believe that I am staring at a 6" PVC pipe at the top of the bore and so seemingly a screen has been "misplaced"

"surface equipment or lift" ? Not sure what these could be but we're pumping direct from subpump into the main tanks

sub pump is 4" Franklin (so SHOULD be trustworthy, right?)

Franklin is probably the brand of the motor and not the pump but in any case should not be a problem.

So then - they were back today with a new impeller and pump unit, both 1.5HP (is this a pathetically small amount of power to be moving such a heavy column of water from such depth?) dropped the new pump down to a newer lower level of 100m....

I agree, 1.5HP is too small but I have attached a performance curve of a similar pump which shows pumping is at least feasible.

It pumped at what seemed like a beautifully ferocious rate flooding the corner of my garden with rich red water (they claim they've spilt mud in....... I'm skeptical......).....

I suspect that no screen has been installed in the bottom of the well and/or it has not been developed.

Then they stuck the giant (brass?) valve ontop of the borehole lid to stop water leaking back from the tanks... (shouldn't that be on the tanks?) and dropped the pump all the way down to 120m..... upon turning on the pump again we got only about half the flow rate (visually) than previously!

You will lose flow rate with the increased pressure but the bottom of your well may also be full of sludge that has never been cleaned out.

so the water continued flow slowly and to clear a little bit over the next hour but is still cloudy..... they say it's too heavy to lift the system now it's so long and so they're coming back tomorrow..... with heavy lifting gear!

Get them sound the bottom of the well in your presence. Feel if the sounding weight is sinking slower near the bottom of the well.

This company do all the big local hotels and seemingly have a fairly good rep for supplying to meet expectations - but I still can't help but smell something highly fishy going on...

Hopefully these facts will help someone to supply me with some more positive points?

I guess this looooooong post could be summed up very easily.....

What should a 1.5HP pump at 120m depth supply as a flow rate in an area where the vast majority suffice with a mere 40/50m? And, yes, I am about 40m above sea level on gently sloping hillside...

See attachment.

Cheers alot forumers.... your eyes are probably bleeding now...... my hands are certainly hurting......

All the best

Chris

Hope this helps. I think at the very least the contractor should re-develop the well with an airlift. There are a couple of tricks involved in this well so let me know if you need further advice.

Good luck.

[waterworks]

Boksida, you're a true gent,

thank you very much for taking out so much time to help.... I am presently rolling my sleeves up awaiting the morning!

Cheers for now, will keep you posted,

Chris