Can flat owner use society water to wash his commercial vehi

In a residential complex commercial activities are not permitted. Submit complaint to Managing Committee and raise the issue in General Body Meeting for banning such activities in the Society..

If bye-law is silent, through General Body, pass a unanimous resolution, that water should be used strictly for household purposes only.  (If someone wants to wash their vehicle they may use bucket without attaching pipe to the mainline)

Yes, it is for the Society management to take a stand on the issue.