RWH must be made compulsory for all buildings, grounds etc and suitable tax breaks must be given to manufacturers of such RWH equipment so that it becomes affordable to all. This will capture a lot of the abundant rain water, thus alleviating the flooding to some extent, and also making use of the rain water so collected for other uses such as raising the ground water levels, storage, car washing, flushing etc. The authorities responsible for various infrastructure debris left uncleared before the monsoons should be fined and also held criminally liable.
