Arghyam and India Water Portal are promoting this design competition with the objective of increasing awareness on the important issue of water as a resources that needs to be conserved and on the role that architects and designers could play in ensuring the same through their designs.
Rainwater Harvesting: http://www.indiawaterportal.org/tt/rwh has a huge amount of material to help you understand rainwater harvesting. There are many websites for Rainwater Harvesting, two notable ones are:
Climate Data: Would you like to incorporate the rainfall pattern in your area into the design ? http://www.indiawaterportal.org/data/metdata has rainfall information for all of India for the past 100 years.
Please note that the above list of resources is only a partial guide. We do not insist that you implement the concepts mentioned and we would like you to explore a wide range of ideas and design concepts beyond those mentioned here.