Hi,
We drilled a 6.5 inch borewell in our apartment, yesterday. According to the driller report, the borewell has 2-3 inches of water. It has three sources around 480ft, 600 and 647ft. The depth of the borewell is 707 ft. After that vendor stopped the drilling saying water pressure was too high for further drilling (though diviner wanted this to be atleast 850ft; the neighboring borewell is 860ft).
However, there were small boulders/gravel founds at 550 ft. The driller suggested to put filter pipe and we agreed. The diameter of the filter pipe is 5.5 inch.
Our requirement of the water is quite high (more than 100000 liter/day). The driller suggested to put 1.25 inch delivery pipe with 5bhp submecible pump. However, some experts suggested 1.5 inch pipe as the yield is quite good. The driller is giving following reasons to have smaller delivery-pipe:
- Maintenance would be easier (in case if we need to take out the motor)
- Width of the borwell is reduced due to filter pipe
- In summer season the water level may go down.
Could you please guide whether this factors are correct? What could be the optimum pump capacity and pipe-diameter?
Some people also suggested to put pebble gravel in the borewell to avoid silt cloaking but drilling contractor is not keen on this. Any suggestion on this? Also where the gravel should be put, around the filter pipe or inside?
Thanks & Regards,
Pradeep