Fresh water is a finite resource, and as water consumption and population increase, many parts of the world are experiencing the effects of reduced water availability. Annual water consumption around the world has risen sixfold during the past century, which is more than twice the rate of population growth. Demand is forecast to continue to grow and by 2025 five and a half billion people, two-thirds of the world’s population, will live in countries that are water stressed. In recognition of the growing water crisis the United Nations General Assembly proclaimed the years 2005 to 2015 the International Decade for Action “Water for Life”.

Water shortages are likely to become an increasing constraint on economic growth throughout the world. Growing population, changing diet and increasing production of bio-fuels will put intolerable pressure on depleted water resources with implications for global security, health and lifespan.