I got the borewell drilled in my site in BTM layout two days back and here is my experience.
- I got the water source identified by a water diviner(coconut method) as well as a geologist. Both indicated drilling points almost at the same location( 1-2 feet distance). Both of them indicated the depth at which the water source will be available as well as the expected yield. Coconut guy indicated a depth of 450-650 feet with a single source of water whereas Geologist indicated a depth of 650-850 feet with 4 different water sources along the way (285, 485, 650 and 850). Geologist even indicated how long the MS pipes need to be provisioned. But I did not see them using any device or formula to arrive at these data. Later the driller mentioned to be that the coconut guy and the geologist just use the past data from that locality to specify almost all of these information and whether we get water is or not is indeed in the divine's hand!!!.
- The water diviner referred a borewell guy (Surekha borewells) and he has also brought the quotation from that guy. Based on the comparison of rates of Kannan borewells, Friends and Surekha, I decided to go with Surekha borewells and fixed the time to start the drilling as 7AM on a Friday.
- The borewell guy did show up at 6AM itself, but the drilling started only at 10AM as they took long time to setup the equipments. There was lot of trouble from a neighbor who wanted his entire building to be protected from any dirt(which I had done partially thanks to some threads from this forum and could not do 100% as his building is 5 storey building!). He started abusing and wanted us to stop the drilling. I tried telling him that I will get his walls repainted or pay the money if he wants to do himself, but he was not relenting. Since it was a helpless situation, I sought the local corporator's help as I had known him and he could fix my neighbor by highlighting his building violations!!!
- The drilling itself was very slow due to soil pattern and also some hiccups of the borewell guy. By end of day1 at 9:30 PM after almost 8 hours of drilling, they had reached only 200 feet and have completed the erection of PVC pipe(55 feet) and MS pipe(170 feet). And we had to stop the drilling to avoid further trouble from neighbors. There was also a water source around 160 feet with 1/4 inch yield along the way.
- On day 2, we started the drilling at 7AM and there was hue and cry from the neighbors that we should start only at 9AM to help people who are sleeping still!. But I told them that BBMP has allowed me to start from 6AM , but have helped them to sleep for an extra hour

. After much discussion, they let me continue the drilling!!!.
- From 170 feet onwards, it was a single rock with white dust covering the entire area till reaching 800 feet depth. It was very depressing and the drilling itself went like watching a suspense thriller movie

. Around 810 feet depth, the white dust stopped and there was small quantity of water and borewell guys told me that the water yield at that point is 1.25 inch. I have no clue how he arrived at this number. Continued the drilling till 950 feet and stopped at 10.15 PM.
- In the end, they flushed the well 2-3 times to remove the sludge and welded a cap on top of the MS pipe and covered the borewell with a gunny sack and completed their dismantling by 11.30 PM on 2nd day. So they took almost 2 full days to drill 950 feet. And the total water yield is 1.5 inch
- The 3rd day was spent in cleaning the road , storm water drain as they accumulated lot of sludge and also cleaning the neighbor's building with a workforce of 6 people!
- The final settlement with the borewell guy was based on the following rates.
6.5 inch bore used
0-250 feet -> Rs 62
250-350 -> Rs 72
350-450 -> Rs 82
450 - 550 -> 92
550 - 650 -> 107 (Rs 15 increase)
650 - 750 -> 122
750 - 850 -> 137
850 - 950-> 157( Rs 20 increase)
950 - 860-> 177
MS Pipe(7inch dia , 2.5 mm thickness, 6Kg per cmsq strength) -> Rs 320 per feet
PVC pipe(10 inch dia) -> Rs 300 per feet
He also charged for welding , borewell cap as well as collars and some miscellaneous charges amounting to around Rs 2500
If I have to summarize, it was an expensive as well as a painful effort to drill this borewell . I am yet to install the pump and will do after couple of months and the borewell guy told me that that is going to cost high as the depth is 950 feet. In spite of all the troubles, I was relieved as there was a decent water yield
Regards,
Selva