Borewell - Common Problems & Solutions Guide

thank you all for yr comments.
i hv got a quote for hydro fracturing, which is quite expensive, so am confused what to do. will try first to do a scanning, then decide future course of action.

tks
moideen

Dear friends please guide me for a proper solution for the below problem

Bore location : near tindivanam

Land details : agricultural residential land

Bore details : 7.5" bore

Pipe details : 6"

Bore drilling distance : 180 ft

Water touched at 120 ft

Pipe distance 60 ft
Further piping not done as bore guy said its enough

PROBLEM FACING:

YESTERDAY WHE N WE TRIED TO CHECK THROUGH HOSE PIPE, IT JUST TOUCHED WET DARK SAND ONLY SO WE
COULD NOT FIX OUR JET MOTOR. I WAS TOLD BY MY BUILDER THAT MAY BE THETE WOULD HAVE BEEN SAND FALLING AS AFTER 60 ft we never added further pipe,

What would have happened? How to get water now and whay is the practical remedy i can be guided

The builder told me that we may have to relay pipes till 120 to 140 ft, by just putting new pipes of 5" dia pipes. Also he suggested of calling the bore guy to flush out the wet soil and to relay extra pipes

O have no idea what to do next and waiting for the bore guy to come and give some genuine rectification suggestions

Please let me know to solve this issue/ to suggest the bore guy to rectify

Regards
Ramaji
9840682147

Dear Ramaji

If you are unable to lower the motor somewhere after 60’ your builder is correct probably borewell wall has collapsed in which case you need to flush your borewell and put casing pipe for the entire length

Also this is common in Chennai and suburbs. The borewell guy suggesting you to stop only for 60’ is very surprising as these guys know Chennai area is prone to wall collapse because of loose soil nature.

Hope this helps.

Regards

Thank you Bhayya,

I have also faced the same Problem. Here it was identified that the Casing Pipe inserted as broken due to negligent attitude of Driller.

Here also same might have happened or the casing Pipe may not have inserted up to Rocky zone. The very purpose of inserting casing Pipe is that to avoid collapsing of loose soil. The casing pipe should be correctly inserted on the top of Rocky zone . Even a small gap at that zone also will give scope in pushing the Mud,Sand will filled up due pressure in the subsoil. It is the responsibility of the driller to set right the Problem. This Problem may setright by further lowering the casing Pipe duly flushing out the mud silted in the borewell provided the casing Pipe has not been broken. while flushing it will be known. If the casing Pipe is broken there is no other go in replacing the casing pipe or lowering the 5" casing pipe in it up to rocky zone.
MANNE.SN,
Vasudha Green Farms,
vasudhagreenfarms@gmail.com,
09133498366

Dear friends / experts !

I have a problem with my bore well.

The total depth of my 4 inch bore well is 40 feet.
The static level of water , i.e, water level from the surface is 15 feet.
The casing pipe of 3 inches dia. is dummied at 35 feet with slots at the bottom five feet.
Nylon cloth is securely fastened at the bottom to filer sand.

Right from 13 feet depth the bottom layers are sandy .

I have a 2 HP single phase mono bloc pump set with three inch suction pipe and 2.5 inch delivery.
The 4 inch casing pipe is used as suction pipe with 4 to 3 inch check valve with leather.

With this arrangement I get sufficient supply of water but the problem is with the water quality.

The water is hard water and I have noticed the young paddy crops die away as if burnt. Previously I thought it was due to hot weather but this time I sowed in March third week when the weather was not so hot. Yet the crops die .

My conclusion is that this may be due to the hardness of water and I am yet to test the water quality.

When the irrigated water dries up, it leaves a white coloured salt layer on the field.

Pleas advise me the remedial measures to be taken.

Thanks in advance.

Thank you Bhayya,

Please get the Water Sample results. Based on the Water Sample Test results only can get the remedial measures. First get the Water Sample as well as soil Sample also. On seeing both te results can identify the reasons for Dying of your Crop.
MANNE.SN,
Vasudha Green Farms,
vasudhagreenfarms@gmail.com,
09133498366

Shortly I may be able to get the water tested but I have to wait till the fate of my ailing paddy crops is known to take up the soil test.

If you can lay your hands on a small EC meter, you can test the salinity in a jiffy.
It may be just the soil even; does the water taste salty too?

Dear Varahaan,

Did this issue suddenly crop up or prevailing?

Looks like pH issue for me.

Check the pH of the soil as well as water.

Balance pH levels between acidic/alkaline and identify if any improvement.

Regards,

This ill effect was noticed first last year.

The water is hard water to drink but not salty ( like sea water ) but definitely hard and leaves a whitish layer on the field when the water evaporates.
By next week I may be able to test the water and post the results.

Please bear with me until then.

As it was raining , I could not take water sample as the analyst had advised me to wait for the land to dry up and the allow the motor to run for at least half an hour before water sample is taken.
So it may take more than a week for me to collect fresh water sample and test it. Soil test can be done after a couple of months.

The water test results are attached. It is in Tamil. Important points are:

  1. pH value : 6.9
  2. Saiinity : 2.9 dS/m
  3. bi-carbonate : 13.4
  4. chloride : 16
  5. Sulphate : 1
  6. Calcium : 8.2
    '7. Mmagnesium : 3
  7. Sodium : 17.05
  8. Pottasium : 0.81
  9. Residual sodium carbonate (RSC) :2.2
  10. Sodium absorption rate (SAR) 7.2
  11. water classification: C2S1R2
  12. Chemical classification: Sodium chloride

Please advise.
Water test Result.pdf (135 KB)

Sodium Chloride is salt.

Try any de-salination process in such a way that it doesnt affect the crops. Organic process is what you need to carry out.

I am not sure if there is any organic process, but reverse osmosis is an option costly although.

Why dont you plan aquaculture like prawn, thats if your interest aligns?

Regards,

Saravana

Now I understand why farmers in our area wait for the monsoon . They usually raise the saplings in September last week and wait for the north east monsoon and transplant. They don’t cultivate in the summer. A lesson learnt the hard way. Is there any salt tolerant rice variety to withstand this level of salinity ?

Hope the below link helps!

timesofindia.indiatimes.com/indi … 596574.cms

My advise is to get in touch with International Rice Research Institute (IRRI)'s Indian Chapter and see if you could source this salt resistant rice variety.

But again why not prawn culture. We recently put up a solar water pumping system near Gummidipoondi, and trust me I never have seen so many aquaculture farms in one particular geo area. And the bore water was super salty!

Regards,

The first advice regarding Salt Resistance Rice Variety is good.

Prawn culture advice is not good as this will in the long run will ruin the entire land around the culture and will make agriculture dead. There are several severe oppositions in many parts of Tamilnadu related to Prawn Culture. Just a few people benefit who does prawn culture and several people do not benefit and it is killing their agriculture (land) and water bodies.

Note: The prawn culture may be possible near the seawater land.

Thank you Padmanaban Sir.

I was unaware of the protests. Quite surprised.

Regards,

Saravana

While drilling the bore-well the air pressure that is given was getting out of a nearby bore-well, (it happened at 520 feet) because of this the sand/dust which was need to come out of the bore-well is not coming and it’s moving towards the another bore-well link nearby. And the Bore-well driller’s mentioned that its risky to proceed further the entire drills will get locked inside and they stopped the drilling process. Is there any possibilities or solutions to proceed further.

Dear all,

Looking for suggestions on what can be done with a failed borewell hole that was drilled about 2 weeks ago.

There’s a bore hole to a depth of 140 feet located on a hillock that did not yield sufficient water. The soil is red lateritic soil and no rock was encountered from the surface right up to 140 feet. At ~140 feet, sludgy water was found soon after which a layer of basalt rock was reached; drilling was stopped soon after this.

The borewell was declared a failure due to insufficient water. The opening at the surface was stuffed with hay, covered with a flat stone and heaped mud. No casing pipes were inserted. I believe a 9" bit was used to drill right up to the point until which rock was reached. The bit was then changed to a smaller one.

I have been wondering what uses this borehole can be put to:

  1. Due to a non-existent monsoon this year, water tables are at a low; this borewell may yield water after the rains begin in earnest.

  2. Use this borehole as a water harvesting unit, after putting in suitable filtration measures.

Both of these require casing to be inserted, this was not done at the time of drilling due to the prohibitive cost - rig operators charge double the market rate for casing pipes. ‘Nandini’ brand of 6.5 inch pipe was being sold at Rs. 250 per foot. This alone would have cost Rs. 35,000.

Assuming there are not yet any cave-ins, I would like to know if:

  1. Casing 6.5" pipes can now be inserted without using the services of the borewell operators, manually, by hand? I’m not sure if a 20’ length of 6.5" pipe can be inserted at all.
  2. What sort of casing is to be used?
  3. I’m told that casing pipes with perforations to allow water percolation are not recommended because the perforations are small and likely to get choked - operators use a solid pipe and cut lengthwise slots to allow water to seep in. Is this true?
  4. Is there any alternate method that can be used in the place of casing, if the borehole is to be used only for water harvesting?

Please help with suggestions and answers. Thank you.

Mr. Prabhu,

To answer your query, there is a possibility to drill further after preventing the Air-loss at the fractured zone by adding the “Drill Mud” diligently.

Drilling Mud is used to -

  1. Prevent cuttings from rapidly settling while another length of drill pipe is added (if cuttings drop too fast, they can build up on top of the bit and seize it in the hole)

  2. create a film of small particles on the borehole wall to prevent caving and to ensure the upward-flowing stream of water does not erode the adjacent formation.

  3. Seal the borehole wall to reduce fluid loss i.e. minimizing the volumes of drilling fluid - Water.

Drilling Mud is a Bentonite Clay that has particularly useful characteristics; it can absorb many times its weight in water. It is useful in drilling wells because water mixed with bentonite tends to coat the wells of the hole and keep it from collapsing.

When you add bentonite to the water two things happen -
a) The water gets thicker and b) the sandy / collapsible walls of the hole solidify to a degree. Both are very helpful in drilling.

Bentonite for drilling comes in a very , very, fine powder. It will likely be the finest powder you will ever see. It is kind of tricky to mix into water. If the driller is not careful it will simply clump. Many a times simply pouring it down the drill pipe is successfully done but I strongly suggest thoroughly mixing it first to improve the performance.

To mix the bentonite, set up a 20 litres bucket near the drill site. Put about 11 litres of water in a 20 litres bucket and pour in the bentonite while you are mixing with a drill and concrete mixing bit. Pouring in the bentonite powder as you are mixing is much more effective than pouring the powder in and then mixing. Add bentonite until it the mix thickens but is still easy to pour. If you add too much it will get hard to pour.

Drill with Cement Mixer Bit

Drill Ready to Mix Bentonite

It is important to keep the Mixer Running while Adding Bentonite

After you get it mixed, you need to get it in with the drilling fluid going down into your hole.

Drill Head with Valve to add Bentonite

For Easy insertion of bentonite mix -

  1. Take the drill head off.
  2. Pour the bentonite mix down the drillpipe. You’ll probably need a big pitcher because it is hard to pour directly from the 20 litres bucket.
  3. Put the drill head back on and turn the water back on.

Then start twisting the drill pipe back and forth and working it up and down in the normal manner.

Bentonite clay additives create thicker wall cakes, penetrate the aquifer and may lesson flow in the near well area unless thorough well development is done to insure the break down and removal of bentonite drilling fluid residues.

After the Bentonite Wall cake is developed at a particular zone in the water well, the further drilling may be carried on with the following rock roller bits to remove the rock core easily upto certain depth below the bentonite sealing to avoid any fractures in the sealed portion.

Rock Roller bits for different kind of Rock strata

However, Before making any decision on well development methods or procedures, it is necessary to check on the exact situation that exists in the zone that is to be developed.

The overriding considerations are -

  1. the cost of the development techniques being considered and the relationship between these costs and value of well.
  2. The Time available.
  3. The availability of required Tools, equipments and materials.
  4. The probability of getting the desired water yield from the borewell.
  5. The risk of getting the desired yield from the borewell or loss of yield.

I hope this would help you in understanding the possibility of drilling further & considering the options for taking an appropriate decision for your water well.

May you have any further queries, please feel free to contact us.

All the Best !

Regards,

YASH D SHAH
(08652810004)