This is typically addressed in water laws of country or state.  As suggested, the effects of unbridled withdrawals may be significant and complex, or not, depending on the circumstances.  Potential impacts can be reduction to streamflow, land subsidence, land productivity decreases, altering vicinity groundwater flow or paths, etc.  Geologists and groundwater hydrologists may be able to assess the circumstances and give you more detail, based on geology, subsurface substrates, areas of recharge, land uses, etc.  Some degree of monitoring may be required to estimate effects to surroundings.  If there are wells in vicinity, monitoring water levels through time would help.  Water level transducers (vented type unless corrected for barometric pressure changes when using an unvented type) can do this such as available for purchase from Global Water, Onset Hobo and others.

If you have a water resources or environmental agency, they may be best to inform you of the laws or regulations.  There is also a body of Common Law that is sometimes applied and court decisions if any relative to water rights, use and situations where the court has decided disagreements.

The question is very pertinent and it can be extended further 'whether it is equitable?' because, those with ability to purchase machinery (pump-sets, pipes, tube-wells, etc.) draws water and sells to have-nots (in absence of clear-cut benefit-sharing arrangement).

This question is pertinent and requires to be addressed at national and international levels. One person's gain is another person's loss in terms of quantity and quality of water, investment in machinery and overall sustainability issue.

The question pertains not only to water but also to air, forestation, flooding etc.  

Thank you researcher friends for good response. and hope further more detailed illustration will be provided by you all. please send me some literature so that I can attempt to address this problem through micro level study in real world situation.