The human right to water is indispensable for leading a life in human dignity and for the realization of other human rights: in particular the right to life, to an adequate standard of living, housing, food, and health. Access to water and sanitation is a sine qua non for the fulfillment of these rights. Almost 900 million people lack access to safe drinking water and 2.5 billion – 40% of the world’s population – have no access to improved sanitation. Failing to ensure access to water and sanitation has immense human costs, both in social and economic terms.