Info regarding site selection of rainwater harvesting structure

The only place for building rainwater harvesting structure within an apartment site is the stilt parking area with a 10 ft roof.  

Are there restrictions in building RWH structure of 3ft dia width and 10ft deep within the apartment stilt parking area in Chennai? With this type of recharge pit, we are apprehensive about whether all this water underground will affect pillars or the foundations of the construction? We do not have any other open area outside to build this recharge pit.

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