Catching the rain where it drops

The shortage of water in recent times seems to have revived the ancient technology of Rain Water Harvesting (RWH) in urban India. Many children who are learning about RWH think it is an innovation of modern day eco-saviours and are surprised to know that civilizations such as the Indus Valley, Greek, Roman had incorporated RWH in their architecture thousands of years ago. Common sense would have told our ancestors that places located away from a sea coast or the banks of a river needed to depend on the rain to meet water requirements, and given that it would not rain through the year, the water that did fall from the sky needed to be saved. The founders of Bangaore knew this too, and that is why Bangalore was once the City of Lakes (rain-fed lakes).