The International Day of water is observed on 22 March. The purpose to celebrate this day is to know and embrace the importance of water in human life. This day is observed by all people, countries and organizations worldwide. For the first time this day was observed in 1993 on the same day. Every year different themes are confined to mark this day. These themes are related to water sustainability, availability and preserving water from waste. The importance of water in human life is immense. It does not require introduction as all human activities rest on the availability of water. Human need water for their survival in every way. A person requires 2 liter of water to drink but to grow food for a person on a daily basis, estimated 3000 liters of water are needed. According to an estimate, agriculture uses 70% of world water. Other human needs include irrigation, domestic use, cooking, washing, inshort every task is dependent on water. The availability of water on earth is...