Boreholes

[xerostar]

I did a search in Google using the terms "water table Hydrology near ocean"

It comes up with a lot of information that helps understand how all it works.

A simple diagram that helps to visualise the system is at:

http://www.whoi.edu/oceanus/viewImage.do?i...14&aid=8267

If there is regular rainfall in adjacent country then there is a high likelihood of finding fresh water.

Apparently the water table generally follows the land contour to a degree.

The fresh water flows out towards the sea through the underground strata or where the water

volume is greatest as rivers, creeks and springs.

Only in long dry seasons can the salt water "flow" inland and contaminate the fresh water.

How far is your property from the ocean? Is it really on a 30 degree slope?

What is the elevation above sea level?

Is it sandy, or rocky? What sort of rocks? Porous limestone, granite or clay formations?

If you find there is no fresh water under your property, maybe you could get permission to drill further inland

and share the water with the owner of that property and pipe the water to your place.

I believe the reference to Jack & Jill had its origins in Politics and didn't have much to do with fetching water.

Hope this helps.

[Alf Witt]

Thanks Xerostar,

You are a mine of information and even if the subject is "boring" you have made it interesting. (couldn't resist that one). We certainly get a lot of rainfall but also drought in the dry season. The foreshore is both sandy and rocky and the rocks are non porous. On land the subsoil is not rocky but I've only seen a depth of a couple of metres. Interesting that the water table follows the contours of the land. It may be worth a try. My guess is it would be unlikely that the salt water would flow uphill much even if there was prolonged drought as gravity would mitigate against that.

I thought that nursery rhymes would be an unlikely source of technical information but you never know. Pop goes the Weasel has a totally different meaning to what one imagines, but I guess thats getting totally off topic.

Thanks again.

[talk4money]

This was very informitive. THanks for the info

BOREHOLES

Lots of us have water boreholes and there are some of us who would like a water borehole.

But you get boreholes and you get boreholes i.e. some will work good & proper for a long time, and some will be nothing but trouble trouble trouble….because the borehole industry in Thailand, like all industries, has its "cowboys".

Some things you can do and some things to look out for when selecting the right man to do the job.

1) Jump in the pickup and drive around a bit – check out who else around you has a borehole and have a chat with them. Find out:

- how deep the hole is

- how much water it produces p/day

- is it year round (or if it changes, by how much does it change).

- what pump do they use (submersible or plunger type – down to around 10m you can get away with a plunger type, much further you're best off with a submersible, they are more expensive)

- how long has it been in use

- lastly, who bored it and what did it cost.

Check out as many as you can around your village/area – that will give you a realistic idea of what you can expect to get from a borehole on your land. You may even want to get a sample of the water and test it yourself for nitrates/nitrites/ calcium ect ect (done easily & cheaply). If its just for the house and garden 3 cubic meters volume a day is fine – which you can pump out with a couple of truck batteries if you have no ac mains power. Yup, so boreholes in rural areas do make a lot of sense.

Generally you have 2 sizes in Thailand: for domestic use you don't need more than a 6" diameter borehole, but for agriculture use and small businesses you want 12" diameter borehole (that's not to say 6" won't do – it can, and often does – just that you'd be better off volume wise if it was 12" diameter).

Check too if you need permission – some areas you'll have to go off and have a chat with the local Phu Yai (village head or District Head at the local district office, and in other areas no-one cares) – but check. The only time you'll get a "no" answer is if you're in an area that is surrounded by industry and the ground water is known to be not safe, or if there is a ground water quota in your area which is been exceeded (there some areas around Bangkok like that, where some industries lift large quantities of H2O from the ground, but out in the "sticks" I have heard of no restricted areas for quota based reasons).

Now's the time to have a chat with the guys who dig the holes – and to take note what you have been told by others, compare it carefully with what the borehole digger tells you – because they can tell some tall stories – for every 10 boreholes dug, at least half of them won't be serviceable after 5 – 10 years and its usually because they weren't dug properly in the first place, not because there isn't any water.

So what are the problems:

1) Slurry Slurry Slurry – other than fuel it's the boreholers biggest expense, but it's the most important component in boring. It will determine how long the borehole lasts and it will determine how many times you have to lift your pump to take stones out the impeller or indeed, replace your pump. The slurry is a mud that is injected down the hole and (because of its density) is used to lift all the loose dirt and in particular the stones, out of the hole as it is sunk. A lot of cowboy borers just do not use it because it cuts their expense. It must be used. It also ensures that the side of the hole are consistant – it will seep into the uneven side wall forming a consistant smooth surface which consolidates the wall and helps to prevent it from collapsing in over time – nothing worse than having a borehole wall that has collapsed in at 30 meters and compressing part of the tube wall – stopping you from retrieving your expensive submersible pump to get the stones out the impeller! So when you go round to see the guy (always best to go & see him first – and then follow it up with a meeting at your place), just look around his yard to see if there are slurry settling tanks lying around. If he uses slurry he'll have settling tanks lying around because they like to collect it as it comes up, let it settle and pump it back down again. No tanks then ask him if you uses slurry. If he says not needed, then move on. IT IS NEEDED to do the job properly – simple as that.

2) Borehole tubing –you get borehole tubing and you get borehole tubing. The cowboys will use the thinnest stuff they can get away with. Go check out the tubing yourself – get a quote from the boreholer, then ask him what the tubing costs, get that taken off and go get it yourself – so you know what's been used and get advise from the hardware store as to what is good tubing and what is not. Don't skimp on the lining.

3) Joining the tubes in the hole: 3 methods – threaded, screwed, pvc adhesive. Use screws and you are asking to be screwed. They will rust if not stainless steel, which will mean if ever you have to lift the lining you will not be able to. If not correctly screwed in they can break, or just as bad – as someone else has reported: they stuck through so far into the hole in his case they prevented him from getting the pump down the hole. The sharps ends can also wreck havock on the power supply cable in the hole over time. PVC adhesive would be a better choice, but again, it's adhesive strength can breakdown over time which again will prevent you from lifting the tubes if you ever need to. End threaded tubes are the best – they form a good tight joint and wont separate.

4) Dropping the pump: if using a submersible use 2 (TWO) stainless steel wire cables – not one. If one snaps you're buggered – try lifting a 10kg submersible from 30 meters on it's power cable. Not wise. Use two cables so you have redundancy and ensure they are stainless steel not normal multi-strand wire steel.

5) Who to use: well, I assuming you have been speaking to the locals who have boreholes and they have all had theirs done by the same guy and they have all been going for 5 or 10 years,, then I guess that's a fair bet. But failing that, and having understood all the above will be adhered to, what else: well, ask the guy if he has hydrology maps for your area. All the professionals will have maps and water table data for your area and will be able to tell you the mean, low and high water table levels for your area, season to season for the last 20 years – something that has been and is monitored very carefully by the authorities all over Thailand.

6) Get a good concreate cap poured around the borehole at ground level – and have a lockable cap on the top of the tube (to stop rubbish getting into the tube and someone nicking your submersible pump – they do get nicked).

How deep will your borehole have to be – well, about as deep as those around you who have boreholes, but there is no average – each area, depending on its elevation above sea level will have its water table at a different height relative to the surface – and will be affected by the geology of the region. Some areas are as shallow as 6 – 10meters for good all year round water supply, and in other areas (like where I am) you have to go down 80 – 100 meters to get year round water. Clay areas shallow, chalky areas deeper, and the deepest boreholes are found in the sandstone and granite areas – which also give the best water as the sandstone acts as a brilliant filter. Chalky areas make the water real hard with calcium.

If anyone has their own "borehole experience" to add – go ahead.

Tim

[timlatyao]

Anyone have a rough idea how the cost compares to putting in a well. I'm pretty fed up with my water supply being turned off 12 hours a day. I've only a small garden so a bore hole would make a lot of sense.

Depends on how deep and what they have to drill through to get to the water. We did one about two years ago, 2-3 metres top soil, 10 metres sandy clay then 30 metres of granite. Baht 336,000.

This followed a ground water survey which cost Baht 60,000 and we had a full geophysical report so we knew where and at what depth the water was. Get 20cum/day.

Hi there

We have just put a bore hole on our farm.

The guys turned up with hand drilling equipment !

I was pretty sceptical, but sure enough they found water after about 10 hours.

At the moment we're pumping thw water out with the help of a bog standard petrol pump which cost 3,600 bht.

The drilling cost 5,500 bht and pipes etc cost about 4,000 more. Seems to work fine.

[Khonwan]

Hi there

We have just put a bore hole on our farm.

The guys turned up with hand drilling equipment !

I was pretty sceptical, but sure enough they found water after about 10 hours.

At the moment we're pumping thw water out with the help of a bog standard petrol pump which cost 3,600 bht.

The drilling cost 5,500 bht and pipes etc cost about 4,000 more. Seems to work fine.

Hi Tim

Depth? Diameter? Flow rate? I don't yet have a bore-hole but I'm thinking about changing that.

Rgds

Khonwan

[khunandy]

If at first you don't succeed etc etc.

Thought I would add my experience here as I now have a good bore supplying our needs.

Last year we had a local driller come in for a "no water = no cost deal, he was very confident of finding good water at a fairly shallow depth, we are in a river valley. Everything was fine for 10 metres or so then he hit granite, that granite went for 50 metres until he ran out of drill string. They worked pretty hard for no real result and I would have paid for fuel but they pulled the PVC casing and scurried off in the night never to be seen again.

We decided to try again this year as the village supply is next to non existent now and the gardens are suffering etc. We engaged a bigger drill rig also on a no water = no pay deal, the contractor picked the spot to drill and away they went. It wqs exactly the same scenario as the first attempt, 15 metres of clay then granite for 40 metres until they also pulled up casing and started to pack up.

I offered to pay 5000 baht for fuel and time so far if they had another go further down the block.

They spent a lot of time water divining and picking the next spot and started again. This time they hit shallow water, 10 - 15 metres I think, they pushed on and then a lot of small river pebbles started to come up with the drill returns ( an old river bed I am thinking) the pebble returns lasted for a couple of metres then hit granite and stopped. total depth about 40 metres.

He supplied a 1 HP Franklin / Shaefer submersible pump for 14000 baht (later seen for 11800 baht ) and we pumped for 8 hrs at 4000 - 4500 litres per hour with loss of volume or pressure. I was very happy. The water was a bit murky for the first couple of hours of pumping but gradually cleared up. It tastes good and doesn't smell so that's a bonus.

I now pump that into a 1500 litre header tank which gravity feeds through a charcoal filter into our 20,000 litre storage tank. An on-demand Hitachi pressure pump then draws on this tank for domestic use.

Cost of drilling : 35,000

PVC, Electrical cabling , pump ,valves etc: 22,000

Incentive: 5000

As a footnote:

I was reluctant to draw power from our domestic supply as we only have a 15 amp supply as it is. The wife arranged another 15 amp supply from the power mob which was connected yesterday for 6000 baht, this included the meter deposit

(2000 baht) The same deal you get for temp power when building a house. In this case we told them we needed it for water to farm a few acres.

Just a final comment, When we were trial pumping the builder who is building a small shop for us came and said "water finished' I groaned and my heart sunk until he explained it was our domestic storage tank....no problem fill it up from the bore..talk about timing :D

I live about 30 kms from Chum Phae, Khon Kaen. Does anybody know where I can get water tested just to see what I have got?

Khun Andy

[dougieboy]

If at first you don't succeed etc etc.

Thought I would add my experience here as I now have a good bore supplying our needs.

Last year we had a local driller come in for a "no water = no cost deal, he was very confident of finding good water at a fairly shallow depth, we are in a river valley. Everything was fine for 10 metres or so then he hit granite, that granite went for 50 metres until he ran out of drill string. They worked pretty hard for no real result and I would have paid for fuel but they pulled the PVC casing and scurried off in the night never to be seen again.

We decided to try again this year as the village supply is next to non existent now and the gardens are suffering etc. We engaged a bigger drill rig also on a no water = no pay deal, the contractor picked the spot to drill and away they went. It wqs exactly the same scenario as the first attempt, 15 metres of clay then granite for 40 metres until they also pulled up casing and started to pack up.

I offered to pay 5000 baht for fuel and time so far if they had another go further down the block.

They spent a lot of time water divining and picking the next spot and started again. This time they hit shallow water, 10 - 15 metres I think, they pushed on and then a lot of small river pebbles started to come up with the drill returns ( an old river bed I am thinking) the pebble returns lasted for a couple of metres then hit granite and stopped. total depth about 40 metres.

He supplied a 1 HP Franklin / Shaefer submersible pump for 14000 baht (later seen for 11800 baht ) and we pumped for 8 hrs at 4000 - 4500 litres per hour with loss of volume or pressure. I was very happy. The water was a bit murky for the first couple of hours of pumping but gradually cleared up. It tastes good and doesn't smell so that's a bonus.

I now pump that into a 1500 litre header tank which gravity feeds through a charcoal filter into our 20,000 litre storage tank. An on-demand Hitachi pressure pump then draws on this tank for domestic use.

Cost of drilling : 35,000

PVC, Electrical cabling , pump ,valves etc: 22,000

Incentive: 5000

As a footnote:

I was reluctant to draw power from our domestic supply as we only have a 15 amp supply as it is. The wife arranged another 15 amp supply from the power mob which was connected yesterday for 6000 baht, this included the meter deposit

(2000 baht) The same deal you get for temp power when building a house. In this case we told them we needed it for water to farm a few acres.

Just a final comment, When we were trial pumping the builder who is building a small shop for us came and said "water finished' I groaned and my heart sunk until he explained it was our domestic storage tank....no problem fill it up from the bore..talk about timing

I live about 30 kms from Chum Phae, Khon Kaen. Does anybody know where I can get water tested just to see what I have got?

Khun Andy

OK nuff of this i'm bored. lol

[PANKA]

PLEASE CAN YOU HELP ME OUT. I AM VERY NEW TO THIS FORUM . INEED TO KNOW HOW TO REGISTER MY BOREHOLE IN SAMUI.

CHARMAINE

This was very informitive. THanks for the info

BOREHOLES

Lots of us have water boreholes and there are some of us who would like a water borehole.

But you get boreholes and you get boreholes i.e. some will work good & proper for a long time, and some will be nothing but trouble trouble trouble….because the borehole industry in Thailand, like all industries, has its "cowboys".

Some things you can do and some things to look out for when selecting the right man to do the job.

1) Jump in the pickup and drive around a bit – check out who else around you has a borehole and have a chat with them. Find out:

- how deep the hole is

- how much water it produces p/day

- is it year round (or if it changes, by how much does it change).

- what pump do they use (submersible or plunger type – down to around 10m you can get away with a plunger type, much further you're best off with a submersible, they are more expensive)

- how long has it been in use

- lastly, who bored it and what did it cost.

Check out as many as you can around your village/area – that will give you a realistic idea of what you can expect to get from a borehole on your land. You may even want to get a sample of the water and test it yourself for nitrates/nitrites/ calcium ect ect (done easily & cheaply). If its just for the house and garden 3 cubic meters volume a day is fine – which you can pump out with a couple of truck batteries if you have no ac mains power. Yup, so boreholes in rural areas do make a lot of sense.

Generally you have 2 sizes in Thailand: for domestic use you don't need more than a 6" diameter borehole, but for agriculture use and small businesses you want 12" diameter borehole (that's not to say 6" won't do – it can, and often does – just that you'd be better off volume wise if it was 12" diameter).

Check too if you need permission – some areas you'll have to go off and have a chat with the local Phu Yai (village head or District Head at the local district office, and in other areas no-one cares) – but check. The only time you'll get a "no" answer is if you're in an area that is surrounded by industry and the ground water is known to be not safe, or if there is a ground water quota in your area which is been exceeded (there some areas around Bangkok like that, where some industries lift large quantities of H2O from the ground, but out in the "sticks" I have heard of no restricted areas for quota based reasons).

Now's the time to have a chat with the guys who dig the holes – and to take note what you have been told by others, compare it carefully with what the borehole digger tells you – because they can tell some tall stories – for every 10 boreholes dug, at least half of them won't be serviceable after 5 – 10 years and its usually because they weren't dug properly in the first place, not because there isn't any water.

So what are the problems:

1) Slurry Slurry Slurry – other than fuel it's the boreholers biggest expense, but it's the most important component in boring. It will determine how long the borehole lasts and it will determine how many times you have to lift your pump to take stones out the impeller or indeed, replace your pump. The slurry is a mud that is injected down the hole and (because of its density) is used to lift all the loose dirt and in particular the stones, out of the hole as it is sunk. A lot of cowboy borers just do not use it because it cuts their expense. It must be used. It also ensures that the side of the hole are consistant – it will seep into the uneven side wall forming a consistant smooth surface which consolidates the wall and helps to prevent it from collapsing in over time – nothing worse than having a borehole wall that has collapsed in at 30 meters and compressing part of the tube wall – stopping you from retrieving your expensive submersible pump to get the stones out the impeller! So when you go round to see the guy (always best to go & see him first – and then follow it up with a meeting at your place), just look around his yard to see if there are slurry settling tanks lying around. If he uses slurry he'll have settling tanks lying around because they like to collect it as it comes up, let it settle and pump it back down again. No tanks then ask him if you uses slurry. If he says not needed, then move on. IT IS NEEDED to do the job properly – simple as that.

2) Borehole tubing –you get borehole tubing and you get borehole tubing. The cowboys will use the thinnest stuff they can get away with. Go check out the tubing yourself – get a quote from the boreholer, then ask him what the tubing costs, get that taken off and go get it yourself – so you know what's been used and get advise from the hardware store as to what is good tubing and what is not. Don't skimp on the lining.

3) Joining the tubes in the hole: 3 methods – threaded, screwed, pvc adhesive. Use screws and you are asking to be screwed. They will rust if not stainless steel, which will mean if ever you have to lift the lining you will not be able to. If not correctly screwed in they can break, or just as bad – as someone else has reported: they stuck through so far into the hole in his case they prevented him from getting the pump down the hole. The sharps ends can also wreck havock on the power supply cable in the hole over time. PVC adhesive would be a better choice, but again, it's adhesive strength can breakdown over time which again will prevent you from lifting the tubes if you ever need to. End threaded tubes are the best – they form a good tight joint and wont separate.

4) Dropping the pump: if using a submersible use 2 (TWO) stainless steel wire cables – not one. If one snaps you're buggered – try lifting a 10kg submersible from 30 meters on it's power cable. Not wise. Use two cables so you have redundancy and ensure they are stainless steel not normal multi-strand wire steel.

5) Who to use: well, I assuming you have been speaking to the locals who have boreholes and they have all had theirs done by the same guy and they have all been going for 5 or 10 years,, then I guess that's a fair bet. But failing that, and having understood all the above will be adhered to, what else: well, ask the guy if he has hydrology maps for your area. All the professionals will have maps and water table data for your area and will be able to tell you the mean, low and high water table levels for your area, season to season for the last 20 years – something that has been and is monitored very carefully by the authorities all over Thailand.

6) Get a good concreate cap poured around the borehole at ground level – and have a lockable cap on the top of the tube (to stop rubbish getting into the tube and someone nicking your submersible pump – they do get nicked).

How deep will your borehole have to be – well, about as deep as those around you who have boreholes, but there is no average – each area, depending on its elevation above sea level will have its water table at a different height relative to the surface – and will be affected by the geology of the region. Some areas are as shallow as 6 – 10meters for good all year round water supply, and in other areas (like where I am) you have to go down 80 – 100 meters to get year round water. Clay areas shallow, chalky areas deeper, and the deepest boreholes are found in the sandstone and granite areas – which also give the best water as the sandstone acts as a brilliant filter. Chalky areas make the water real hard with calcium.

If anyone has their own "borehole experience" to add – go ahead.

Tim

[crazyswede]

Great Thread .. been asking around for this on other forums but no one seams interested , looks like they are happy with the "Government water" but i know where it come from so i rather have my own!

Thanx!

CS//

[Sattahipoz]

Anyone in the Chonburri Sattahip Rayong area got a price and / or name of a decent and reasonable water boring operator??? Appreciate any feed back

[Rinrada]

Good to see this one back up and running.

Now that we have just about got the hoose in a fit state for living I gotta now consider a Bore .....might already be considered one but thats another argument.

Our present nam supply comes from the local dam (methinks) and is pretty good and reliable but then goes on to feed our local village..so one reason.

Also want to seriously do a bit of proper gardening on our 25-30 Rai..

We have also decided to increase our herd from 6 (pet ) cows/bull and bring it up to around 20 ...for milk... and also...heavens elp uz...are looking at DUCKs...maybe 200 to start wiff

Also in future i want a wee "wai nam"....but for the time being just need lots of water.

so any reccommendations - Non Rip off merchants around Chiang Mai?...appreciated

Cheers R

[slapout]

Send Boksida (TV member) a pm and he can get you fixed up and answer your questions, I am sure.

[MrWiggle]

Anyone have/heard any experience in the Ban na area for a bore ?

Was recently quoted 170k for 2" and 3hp pump......did not like that quote.

[genset]

For anybody out there thinking about having a borehole drilled, I would recommend you read the attached document from cover to cover. Lots of great info to help you decide if the job is being done correctly, I hope you find the document to be of use.

As this is the Farming in Thailand forum I'd like to add a shameless plug for my thread in the 'DIY Housing Forum' if I may.... If anybody out there is looking for information or advice on the installation and operation of standby or prime power generators in Thailand, my thread can be found here http://www.thaivisa.com/forum/Generators-T...nd-t309747.html

Good luck and happy drilling...

Genset

Lifewater_Drilling_Manual_2004.pdf

[MrWiggle]

My Thai project manager was just quoted 120,000 baht for:

9" bore-hole

up to 100m deep (they said 50-70m is probably what we'll end up needing)

including submersible pump and motor etc

screw-together tubing

10% deposit

40% on completion and working after a few weeks

remaining 50% after 12 months if everything is still ok

will take about 10 to 20 days to do unless they hit a ton of granite (same price, their hard luck)

Location is Phitsnulok. Seems quite a fair deal to me?

I have about 120 rai to supply, and new lakes to build/fill etc.

Know this is an old post...but any contacts for this mob ?

Sounds like a very fair deal.

[Boksida]

My Thai project manager was just quoted 120,000 baht for:

9" bore-hole

up to 100m deep (they said 50-70m is probably what we'll end up needing)

including submersible pump and motor etc

screw-together tubing

10% deposit

40% on completion and working after a few weeks

remaining 50% after 12 months if everything is still ok

will take about 10 to 20 days to do unless they hit a ton of granite (same price, their hard luck)

Location is Phitsnulok. Seems quite a fair deal to me?

I have about 120 rai to supply, and new lakes to build/fill etc.

Know this is an old post...but any contacts for this mob ?

Sounds like a very fair deal.

With a deal like that, they would not have stayed in business for more than a couple of months so it might be best to start looking from scratch.

[slapout]

Have to agree with Bosida. Sounds like time share, with no place to stay, get a group of suckers to put up 10% each and abscond with the monies.

[yabaaaa]

Anyone got a borehole in Pranburi and if so who did you use. My land is sandstone. Thanks 16km inland direct from Sam roi Yot 50 metres above sea level

[thaidrav]

Can anyone recommend a borehole company in Kanchanabhuri?

[longball53098]

You may even want to get a sample of the water and test it yourself for nitrates/nitrites/ calcium ect ect (done easily & cheaply).

We recently had a bore completed here in Phala Beach, Rayong. 43 meters deep and 6 inch with a Franklin 1 hp submersible. Water is being used for the garden and grass/trees. Water has a distinct well smell and now after a month leaving the tell tale rust colored stains on the walls and walks. My feeling is high iron content.

The quote above is from the OP and mentions testing the water but no where in the topic do I see anyone saying they have tested or where they had the tests done? Or how much? I located via web surfing two companies in BKK that can do water quality testing and charge about 10k baht for a complete series of tests including bacteria but I would have to get the samples to them within the required time frames to allow the proper testing.

So does anyone know of a all in one kit that can do water testing for the 10 or 12 basic types of tests that can be done? If I were back in the US I could go down to the local hardware store and buy any of 5 or 6 test kits to do the job for about 25 USD.

Now if my well has high iron and manganese what can I do to filter it and how much will that cost? Any experienced folks that have been down this road already?

Thanks in advance for any help.

[Boksida]

Now if my well has high iron and manganese what can I do to filter it and how much will that cost? Any experienced folks that have been down this road already?

High iron is a common problem in Thailand but fairly easy to treat. The water needs to be aerated first before filtration. If I remember correctly, this converts the dissolved ferrous iron into solid ferric iron which is easier to filter. Aeration is usually just a matter of a shower head or cascading over trays or louvres. A sand filter will then remove the red product. This can be a commercial filter available at most hardware stores or a sand column in concrete rings. Whatever filter you decide on, you will need the necessary plumbing to be able to backwash it as a fair amount of red crud (technical term) builds up.

Your well driller may be able to point you in the right direction.

[longball53098]

Thanks for the suggestion/information. This idea would pose a problem for me then I would need to add some way to do this aeration method then capture this back to a tank to filter and pump to the sprinklers.

If nothing is done will the high iron cause issues for trees/garden/grasses?

[old wanderer]

Well I have just re-read this thread....Time flys, but back in the late 80s early 90s I was a coyboy and had a ranch (5000 acres). In one of my trade deals I ended up whit a Buycres Erie well drilling rig. I drilled well on the ranch up to 16" casing size and over 300 meters deep. A poor flow for me was 700 GPM pumping from a water head at 150' and my best well flowed 3000 gallons per minute using a 200 Hp electric pump...(It is absolutly awsome to flick a switch and watch a 12" diameter pipe throw water 20' sideways befor hitting the ground.

So a few suggestions for those in a sand area:

1. I have always used steel 1/4" wall welded casing....

2. There are well engineered sand screens for pulling water from sand layers...not too expensive and sized for your casing..(I think 6" is the smallest) 6" was also the smallest casing I ever set drilling with an 8" bit and after the casing is set, throw a bag of concrete to seal the base, then pea gravel then dirt, the about 10' down another bag of cement or 2 to prevent ground water entering your well water and contaminating it. (Especially if you have live stock around).

Next time I go to Thailand I am going to ask around about what equiptment is available..Cable tool if heavy enough, rotary, or reverse rotary, or hammer drills, all have thier places. I now regret I sold my well rig and all the stuff as I would have enjoyed making a real well.

One well I did complete was a 860' well with 14" casing. I used a 8" 5 stage pump driven by a 100 HP gear head connected to a diesle engine. I was flowing 650 gpm and 70 PSI to power a water powered center pivot that would irrigate a 200 acre field about 1" of water every 3 days.

[ronoh08]

We drilled a hole in Ban Pho(small village)

The price was 1500 baht:- for the ring and 3 person working all day. It does work. The have some people in the village doing that. My gf uncle used to be doing that before he where married.

The earth is sandy out here in Issan.

[MrWiggle]

Drove past a development today and drove in for a looksie.

Saw a water drilling rig hiding up around the bend and we asked about drilling at our place just up the raod.

He is going to come by and look, but the jist of it on the spot was 170k for guaranteed water, 6 inch pvc casing and all pump and connections inclusive.

We did not go into great detail there as he was busy, but when he comes to look we shall ask all the other questions and I shall report his info and what exactly you get for the 170k

He was contracted to big 5 bores on this property, had just started the first one and was down 60 odd meters and just hit muddy soil.

This development is located in a valley which is surrounded by rocky outcrops and stone everywhere.

I might even pop back to see how he is going there onsite in a few days.

[MrWiggle]

Ok, here is the results of 2 interviews of guys drilling in my area. The first guy is drilling 5 bores for a new resort about 5/10k's from our house, he is based in Saraburi about an hour from where we live and the second is drilling about 15k's from us, but he is a local and lives in the area and has drilled a few in our valley.

First guy's price is 170,000 and you get for this...

A 6 inch bore with 4 inch inner pipe.

No slurry used, he explained they used an air compressor and such, missus could not get the idea of mud/slurry across to him.

Pump is to be advised, but seems can choose the brand if we want not what they supply. HPalso depends on the water flow they hit, but will be 1.5 or 2hp.

Only 1 cable attached to pump and is bronze or brass or such, not stainless.

Piping is glued, not screwed together or from sides at all.

Pipe is 8.5mm thick.

Guarantee to find water but wants 20k for fuel regardless.

Quotes around 100m to get to good water in this area.

Guarantee good water with a flow of at least 3500lt/hr.

3 phase power not required.

Bore capped with 1m x 1m slab with control box and cutoff switches.

Second guy....

Price is 75,000

A 6 inch bore with 4 inch inner pipe.

No slurry used as above.

Pump is Franklin 1hp, but can upgrade to 1.5hp for extra 5k baht, but seems can choose the brand if we want not what they supply.

Only 1 cable attached to pump and is stainless.

Piping is glued, not screwed together or from sides at all.

Pipe is 8.5mm thick.

Guarantee to find water.

Quotes around 40m to get to good water in this area.

Guarantee good water with a flow of at least 3500lt/hr.

3 phase power not required.

Bore capped with 1m x 1m slab with control box and cutoff switches.

Additionaly he will drill futher but cost more, not sure how much yet per metre.

Quotes he drills till he finds good water, no need to go to 100m around here.

Guarantees the system for 12 months to fix free, if after 12 months it runs dry, he will pull and drill again deeper for 12,000b only for fuel.

Lives in the area, so some assurance he will come to fix problems quickly if any.

Not sure on his depth quotes thouhg. He just finished a bore in the area that we saw and weent down to 33m only and got 10,000lt/hr.

So, whats the experts think. have not found anyone that uses slurry...surely if a lot are not using it, there might be reasoning for not, or an alternative method. Both had a very large compressor on the back of a seperate truck.

[MrWiggle]

Ok, here is the results of 2 interviews of guys drilling in my area. The first guy is drilling 5 bores for a new resort about 5/10k's from our house, he is based in Saraburi about an hour from where we live and the second is drilling about 15k's from us, but he is a local and lives in the area and has drilled a few in our valley.

First guy's price is 170,000 and you get for this...

A 6 inch bore with 4 inch inner pipe.

No slurry used, he explained they used an air compressor and such, missus could not get the idea of mud/slurry across to him.

Pump is to be advised, but seems can choose the brand if we want not what they supply. HPalso depends on the water flow they hit, but will be 1.5 or 2hp.

Only 1 cable attached to pump and is bronze or brass or such, not stainless.

Piping is glued, not screwed together or from sides at all.

Pipe is 8.5mm thick.

Guarantee to find water but wants 20k for fuel regardless.

Quotes around 100m to get to good water in this area.

Guarantee good water with a flow of at least 3500lt/hr.

3 phase power not required.

Bore capped with 1m x 1m slab with control box and cutoff switches.

Second guy....

Price is 75,000

A 6 inch bore with 4 inch inner pipe.

No slurry used as above.

Pump is Franklin 1hp, but can upgrade to 1.5hp for extra 5k baht, but seems can choose the brand if we want not what they supply.

Only 1 cable attached to pump and is stainless.

Piping is glued, not screwed together or from sides at all.

Pipe is 8.5mm thick.

Guarantee to find water.

Quotes around 40m to get to good water in this area.

Guarantee good water with a flow of at least 3500lt/hr.

3 phase power not required.

Bore capped with 1m x 1m slab with control box and cutoff switches.

Additionaly he will drill futher but cost more, not sure how much yet per metre.

Quotes he drills till he finds good water, no need to go to 100m around here.

Guarantees the system for 12 months to fix free, if after 12 months it runs dry, he will pull and drill again deeper for 12,000b only for fuel.

Lives in the area, so some assurance he will come to fix problems quickly if any.

Not sure on his depth quotes thouhg. He just finished a bore in the area that we saw and weent down to 33m only and got 10,000lt/hr.

So, whats the experts think. have not found anyone that uses slurry...surely if a lot are not using it, there might be reasoning for not, or an alternative method. Both had a very large compressor on the back of a seperate truck.

[metisdead]

Ok, here is the results of 2 interviews of guys drilling in my area. The first guy is drilling 5 bores for a new resort about 5/10k's from our house, he is based in Saraburi about an hour from where we live and the second is drilling about 15k's from us, but he is a local and lives in the area and has drilled a few in our valley.

First guy's price is 170,000 and you get for this...

A 6 inch bore with 4 inch inner pipe.

No slurry used, he explained they used an air compressor and such, missus could not get the idea of mud/slurry across to him.

Pump is to be advised, but seems can choose the brand if we want not what they supply. HPalso depends on the water flow they hit, but will be 1.5 or 2hp.

Only 1 cable attached to pump and is bronze or brass or such, not stainless.

Piping is glued, not screwed together or from sides at all.

Pipe is 8.5mm thick.

Guarantee to find water but wants 20k for fuel regardless.

Quotes around 100m to get to good water in this area.

Guarantee good water with a flow of at least 3500lt/hr.

3 phase power not required.

Bore capped with 1m x 1m slab with control box and cutoff switches.

Second guy....

Price is 75,000

A 6 inch bore with 4 inch inner pipe.

No slurry used as above.

Pump is Franklin 1hp, but can upgrade to 1.5hp for extra 5k baht, but seems can choose the brand if we want not what they supply.

Only 1 cable attached to pump and is stainless.

Piping is glued, not screwed together or from sides at all.

Pipe is 8.5mm thick.

Guarantee to find water.

Quotes around 40m to get to good water in this area.

Guarantee good water with a flow of at least 3500lt/hr.

3 phase power not required.

Bore capped with 1m x 1m slab with control box and cutoff switches.

Additionaly he will drill futher but cost more, not sure how much yet per metre.

Quotes he drills till he finds good water, no need to go to 100m around here.

Guarantees the system for 12 months to fix free, if after 12 months it runs dry, he will pull and drill again deeper for 12,000b only for fuel.

Lives in the area, so some assurance he will come to fix problems quickly if any.

Not sure on his depth quotes thouhg. He just finished a bore in the area that we saw and weent down to 33m only and got 10,000lt/hr.

So, whats the experts think. have not found anyone that uses slurry...surely if a lot are not using it, there might be reasoning for not, or an alternative method. Both had a very large compressor on the back of a seperate truck.

Drilling a well on slurry would be required if the formation is sandy, sandy clay and loose formations, in this case slurry prevents the collapse of the hole while drilling as well as to keep the hole open while running casing.

Drilling a well using air compressor is generally accomplished when the formation is solid (sandstone, limestone, etc.) and not prone to collapse.

[MrWiggle]

Good to hear, we are in a stoney area.

[Boksida]

Mr Wiggle,

I concur with metisdead's comments - air drilling is the norm in consolidated formations. Depth is limited by the pressure rating on the compressor and you could use 10 meters of depth per bar of pressure as a rule of thumb. The other advantage is that you can see how much water your well be able to produce while the drilling is taking place.

Re the other specifications:

6" bore with 4" casing should be fine for the yields you are expecting.

Glued joints will normally be OK if care is taken. I prefer to add stainless steel screws or pieces of PVC rod to assist with tensile strength but not absolutely necessary.

I doubt the wall thickness is 8.5mm but rather suspect it is the standard pressure rating (in bar) of a class of locally available PVC pipe. Class 13.5 is better but reduces the internal diameter of your well. Specifications are available here.

No problem with single phase power with motors less than 5HP.

The commercial details are up to you and your degree of confidence in the contractor. The local guy may have the better price because he is more confident on how deep he will have to drill at your location. At near to 30 baht per liter for diesel fuel for a thirsty compressor, I pity both the guys.