tthan is an NGO based in Ahmedabad. It has worked on water , peace and livelihoods issue for long apart from others. This rooftop rainwater harvesting project was implmented in a drought prone village called Mithi Virdi in 1997-98 . More than 120 rainwater tanks were built to provide 10litres of water per person per day for 4months as lifeline water. These tanks continue to function even today in March 2009 with all households using the rainwater exclusively for drinking and cooking purpose.