A parched waterworld
The doomsday predictions of wars being fought over water indicate the world's precarious position with regard to water. Though 70 per cent of the planet is covered by water, only 2.5 per cent of water is freshwater. Of this, nearly 70 per cent is frozen in the ice caps of Antarctica and Greenland. The rest is present as soil moisture and in deep underground aquifers. As a result, only a minuscule 0.007 per cent of water on the planet is readily available for human consumption.
If the world's total river flow is divided by the world's population in 1995, the average is 7,300 cubic metres of water per person per year. This is a drop of 37 per cent since 1970. It must be noted that water distribution in the world is very uneven. While the Amazon carries 16 per cent of the global run off, the arid and semi-arid zones of the world that constitute 40 per cent of the land mass receive only two per cent of the global run off.
With a projected increase of 50 per cent in population in the next 50 years and the expected increase in demand as a result of economic growth and changes in lifestyles, the future does not look very bright, unless there is proper planning and management of water. Agriculture, industry and basic human needs, such as drinking and sanitation, make up for the most important uses of freshwater. Of late, the ecosystem is also being viewed as a user of water. And in all probability, the most important user of water.
"The severity of the recent floods in Europe and in North America indicate that run off water has been denied access to the natural absorbing or sponging areas such as wetlands and marshes,' said Janet Abramovitz of the Worldwatch Institute, Washington, dc . "By ignoring nature as a rightful shareholder in water resources, present development trends can lead to worsening of the situation, like the proposed irrigation plans in the Mekong valley, which will directly affect over 50 million people, besides the natural system,' she adds.
According to Comprehensive Assessment of the Freshwater Resources of the World , a 1997 report prepared by the World Meteorological Organisation ( wmo ) on behalf of a host of un agencies: "Water needed to be left in rivers to maintain healthy ecosystems.' This reflects the acknowledgement of the ecosystem, hitherto taken for granted, as an equal partner in the use of water. If one goes by the above-mentioned projections whereby all the usable water would be consumed by humanity in the coming 50 years, the ecosystem would be starved of substantial replenishment.
Global withdrawals of water have grown by a factor of over six between 1900 and 1995