Is digging a new borewell a solution in a city like Chennai?

We live in Medavakkam area (Palm Avenue, Gayathri Nagar, Medavakkam) Chennai. We have dug our borewell upto 80 ft 5 yrs ago and this year we are facing frequent air block issue. Neighbours started digging new borewells next to the existing one, to a depth of120 to 300 ft.

I would like to understand if neighbours digging borewell to 300 ft is the cause of the water scarcity. Also what is the permanent solution for our issue. Do we need to dig another borewell. If this is the solution how long will this be the source of water. Please guide us in giving a permanent solution for our problem.