Sudden drop in borewell yield in Bellandur, Bangalore, Karnataka - Need a remedy

I live in an apartment complex in Bellandur Bangalore. This area is thick with apartments and everyone has borewells. One of our borewells with a depth of 913 ft has suddenly dropped in yield. We had a yield test done a 15 days earlier and as per the report the static water level is 450 ft. This borewell is the main source of water to the apartment buildings and the drop of 30-40% is a significant impact. What actions/checks would you recommend? Should we inspect the pumps of the borewell? Is it safe to lift up the pumps - an earlier borewell a few feet away collapsed and some of us are worried about the risk of damaging the borewell. 


thanks again for your support.