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water > factfile
Supply
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. ... more
Demand
While freshwater supply is limited, demand keeps on escalating as populations grow and consumption per capita increases. During the last 70 years, the global population has tripled, but water withdrawals have increased over six times. Since 1940, annual global water withdrawals have increased by an average of nearly 3 per cent per year, while population growth has averaged between 1.5 and 2 per cent. ... more
Water use
Water use is increasing everywhere. The world's 6.7 billion people are already appropriating 55 per cent of all the accessible freshwater contained in rivers, lakes and underground aquifers. ... more
Water shortages
Despite a slowdown in population growth rates and family levels in many countries, the world's population is still growing by some 78 million per year. Finite water resources are coming under increasing pressure from population growth and over-use (See Figure 1). This number implies an increased demand for freshwater of about 64 billion cubic metres a year - an amount equivalent to the entire annual flow rate of the Rhine River. ... more
Water pollution
Not only is freshwater water being over-used and wasted, it is also increasingly polluted. Each year roughly 450 cubic kilometres of waste water are discharged into rivers, streams and lakes. To dilute and transport this dirty water before it can be used again, another 6,000 cubic kilometres of clean water are needed - an amount equal to about two-thirds of the world's total annual useable freshwater runoff. If current trends were to continue, the world's entire stable river flow would be needed just for pollutant transport and dilution by the middle of this century. ... more
Conflict over water
Some commentators believe the imperative to share water across national borders could be a force for co-operation and peace. Others feat that conflicts over water - both political and violent - could erupt in coming decades as more countries, with ever larger populations, face water stress or scarcity. Dr. Peter Gleick, President of the Pacific Institute for Studies in Development, Environment and Security, puts it bluntly: the potential for conflict "is symptomatic of our inability in general to managed limited supplies of freshwater on a sustainable basis." ... more
Irrigation
On a global basis, agriculture accounts for 70 per cent of all annual water withdrawals. (In developing countries water consumption for agriculture is typically 70-80 per cent of total water consumption). The overwhelming bulk of this water is used for irrigated agriculture; only a tiny amount is accounted for by livestock. Some 40 per cent of the global harvest comes from the 17 per cent of cropland that is under irrigation. ... more
Groundwater depletion and pollution
About 2 billion people, approximately one-third of the world�s population, depend on groundwater supplies, withdrawing about 20 per cent of global water (600-700 km3) annually � much of it from shallow aquifers. ... more
Health and freshwater
Of the 6.7 billion people on earth today, about 1.2 billion people lack access to potable freshwater and 2.6 billion do not have access to adequate sanitation facilities. ... more
Degraded rivers worldwide
More than half of the world's major rivers are either heavily polluted and/or drying up in their lower reaches because of over-use, according to the World Water Council. Of the world's 500 major rivers, 250 are seriously polluted and depleted from overuse. Contamination and overuse of river basins displaced some 25 million environmental refugees in 1998/99. ... more
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