Supply

Posted: 26 March 2008

Around 75 per cent of the planet consists of water. 97.5 per cent of this water is contained in the oceans, hence salty and unsuitable for drinking or irrigation. Of the 2.5 per cent that is freshwater, just one-hundredth of one per cent (0.01 per cent) of the world's total supply - amounting to some 14 billion cubic metres - is considered easily accessible for human use on a regular basis. This water is found in rivers, streams, lakes and shallow aquifers. Much of the rest is tied up in inaccessible ice fields and glaciers.

Click here for a graphic illustrating the quantity and distribution of the world's freshwater resources in glaciers and icecaps, groundwater, and in wetlands, large lakes, reservoirs and rivers.

  • Groundwater aquifers store as much as 98 per cent of accessible freshwater supplies. They provide 50 per cent of global drinking water, 40 per cent of industrial demands and 20 per cent of water for agriculture (UNEP).

  • The supply of freshwater is finite. There is no more freshwater on earth now than there was 2000 years ago when the population of the planet was less than 3 per cent of its current size.

    Click here for a map showing the availability of freshwater in 2000

  • Over 1.2 billion people lack a reliable supply of drinking water and 2.6 billion have no effective sanitation. In all, 62% of Africans have no access to sanitation facilities. And more than 300 million Africans lack a fixed water supply.

  • Improved water management has brought enormous benefits to people in developing countries. In the past 20 years, over 2.4 billion people have gained access to safe water supplies and 600 million to improved sanitation (UNEP).

  • Although the amount of available freshwater is enormous, water is not distributed evenly around the globe, throughout the seasons or from year to year. Two-thirds of the world's population - around 4 billion people - live in areas receiving only one-quarter of the world's annual rainfall.

    thumbnailClick here for a map showing levels of water stress around the world.

    water scarcity mapsClick here for maps showing freshwater scarcity worldwide and projected water scarcity for African nations in 2025.

Related links:

Official site of the International Year of Freshwater 2003

IUCN facts and figures about water

UN Environment Programme