Implementing RWH in a govt. hospital : Need advice regarding plan procedures & funding sources

I am working as a medical officer in a Government Hospital. My hospital is shifting to a new building next month. But unfortunately no measures have been taken to add rain water harvesting to the plan of the new building. Can we have a separate plan for the RWH structure or can it be added to original one? Is there any government department that offers fund allotment for implementing RWH systems? Or can I apply for the same through the zilla panchayath or is there any other method. Kindly provide information regarding funding sources and application processes.

Mr. Kantharaj