Section 4B(2)(a) in The Special Rules for the Mulit-storeyed and Public Buildings, 1974
(a)Subject to sub-rule (1), every owner or occupier of a building shall provide rain water harvesting structure in such building in the manner specified in rule 4-A on or before the 31st August, 2003. If the owner or occupier of the buildings fails to provide the said rain water harvesting structure by the said date, the Commissioner or any person authorised by him in this behalf may, after giving notice to the owner or occupier of the building, cause rain water harvesting structure to be provided in such building and recover the cost of such provision along with the incidental expense thereof in the same manner as property tax. This however, does not absolve the liability of the owner or occupier of the building from providing the rain water harvesting structure before the 10th October, 2003.