Human survival since ages has depended on the relationship societies had with land and water resources. This relationship has been evolving even since riverbanks and river valleys influenced the early human settlements. Many early civilizations have flourished on the riverbanks, and perished in the river floods - some probably due to the faulty watershed/river basin management. However, eventually human beings had come to understand the cyclical relationship of water with land. This understanding led to the creation of tanks using highly developed engineering techniques. The time span for such development can only be guessed; might have happened over centuries. But, this knowledge has enabled us to live and settle at places of our choosing, not necessarily on the riverbanks or in the valleys. While floods still cause havoc in many parts of the world, they have ceased to be the scourge of civilizations.