Water is essential for life. No living being on planet Earth can survive without it. It is a prerequisite for human health and well-being as well as for the preservation of the environment. However, four of every ten people in the world do not have access to even a simple pit latrine; and nearly two in ten have no source of safe drinking water. Every year millions of people, most of them children, die from diseases associated with inadequate water supply, sanitation, and hygiene. According to the World Health Organization, each and every day some 3,900 children die because of dirty water or poor hygiene; diseases transmitted through water or human excrement are the second-leading cause of death among children worldwide, after respiratory diseases. Water scarcity, poor water quality, and inadequate sanitation negatively impact food security, livelihood choices, and educational opportunities for poor families across the world. Water-related natural disasters such as floods, tropical storms and tsunamis exert a heavy toll in human life and suffering. And all too regularly, drought afflicts some of the world's poorest countries, exacerbating hunger and malnutrition.