The problem

In the year 2002, it was reported that 1.1 billion people lacked access to improved drinking water sources and 2.6 billion people lacked access to improved sanitation [1]. In some less developed world regions, the proportion of the population lacking access to improved water supply and sanitation (WS&S) was disturbingly high, especially for improved sanitation access. In terms of overall numbers, more than 90% of the world's population lacking access live in Asia and Africa. In fact, around 70% of the 1.1 billion lacking access to improved drinking water sources and around 78% of the 2.6 billion lacking access to improved sanitation access are located in just 11 countries [2].

Unsafe and inaccessible water and sanitation is a human problem for many reasons, covering personal hygiene and dignity, disease risk [3], environmental impact, as well as overall developmental impact related to health status, time use and production decisions. Furthermore, coverage of improved water and sanitation is strongly related to household income and dwelling location, thus indicating severe inequalities in society such as between the rich and the poor, and between rural and urban populations [1].

The real size of the water and sanitation problem is worse than past statistics suggest. The ramifications for humans of unsafe water and lack of sanitation are expected to become worse over time due to unsustainable water consumption, increasing contamination of water sources, changing rainfall patterns, population movements, increased water demands from agriculture, and decaying infrastructure which has not been adequately maintained.