In the month of October 2007 at Rajajeswarinagar Bangalore, we dug a bore well to a depth of 301 ft in consultation with a geological person. In December 2007 fixed up 100 mm, 1hp oiled cooled motor to a depth of about 100 ft, as we are stuck with a boulder.
The report of the driller is as detailed:
I] Yield :- 1st spring 90 ft – 1½” , 2nd spring 120ft - 1 ½” & total yield of 3” water. 120 ft Heavy Boulders.
2] 6 ½” – 2mm M S Casing to a depth of 77 ft, 10” PVC casing for 8’.
The water was good with continuously flowing during construction period of about 8 months & also even after occupation till last may 2009. It so happened in May 2009, that the motor was on for about 5 Hr in one night as a result the pump failed. Consequently the water source had also gone down below the 90 ft. In consultation with the Bore well person tried to break the obstructing boulder by dropping a heavy/solid steel rod of 4 ½” diameter of 2ft length. Unfortunately after breaking the protruding boulder, the rod stuck at 90 ft along with the wire rope. Several attempts to pullout with tri-pod arrangement were futile. Subsequently it was removed by blasting with a single stick. Due to the filled- up debris & silt the motor stopped at a depth of 125 ft.
According to the Bore well person the water is available at 125 ft and advises to go for 1] Compressor Air Cleaning & 2] To insert HDPE Perforated Pipe to full depth. And also advises to go for a new well which will definitely costs more & due to lack of open space limits the location of an another successful well.
Now, I am in a dilemma weather to go head with the advice or to abandon, for which my feelings are not permitting. I seek expert’s advice with my sincere thanks in this matter.
1. What is the effect of blasting to the building?
2. If to use HDPE filter pipe, what should be quality – Grade, Thickness. Brand, approx. cost, etc., for longer life.
3. Is the Oiled Cooled 1hp motor suitable?
4. What type of Electrical Cable is required - Grade, Brand, approx. cost, etc., for longer life.
5. Domestically how to get to know the depth of water availability at frequent intervals.
S Ravishankar
s_ravishankar57@hotmail.com