I have sunk a borewell about 10 years back for a depth of 240 feet. A 1 HP submersible pump was lowered upto 110 feet.  Recently since we were not getting much yield, as per local advice, we lowered the pump by another 70 feet, to 190 feet.  Now the yield has further reduced.  Our overhead tank (2000 ltrs) is placed at 30 ft above ground.

1. My house is at Annasandrapalya, HAL, Bangalore
2. Whether the motor is too old and of lesser capacity and do we need to change it. If yes, what should be the ideal capacity  (Depth 200 ft + 30 ft above ground)
3.  How to assess whether the yield in the borewell has reduced. Owing to the construction, there is no scope of increasing the depth of the borewell.

Jaishankar
jaishankar@manipalhealth.com