Water: A rare and precious resource
Fresh water is a scarce commodity. Since it's impossible to
increase supply, demand and waste must be reduced. But how?
Water is a bond between human beings and nature. It is ever-present in our daily lives and in our imaginations. Since the beginning of time, it has shaped extraordinary social institutions, and access to it has provoked many conflicts.
But most of the world's people, who have never gone short of water, take its availability for granted. Industrialists, farmers and ordinary consumers blithely go on wasting it. These days, though, supplies are diminishing while demand is soaring. Everyone knows that the time has come for attitudes to change.
Few people are aware of the true extent of fresh water scarcity. Many are fooled by the huge expanses of blue that feature on maps of the world. They do not know that 97.5 per cent of the planet's water is salty - and that most of the world's fresh water - the remaining 2.5 per cent - is unusable: 70 per cent of it is frozen in the icecaps of Antarctica and Greenland and almost all the rest exists in the form of soil humidity or in water tables which are too deep to be tapped. In all, barely one per cent of fresh water - 0.007 per cent of all the water in the world, is easily accessible.
Over the past century, population growth and human activity have caused this precious resource to dwindle. Between 1900 and 1995, world demand for water increased more than sixfold - compared with a threefold increase in world population. The ratio between the stock of fresh water and world population seems to show that in overall terms there is enough water to go round. But in the most vulnerable regions, an estimated 460 million people (8 per cent of the world's population) are short of water, and another quarter of the planet's inhabitants are heading for the same fate. Experts say that if nothing is done, two-thirds of humanity will suffer from a moderate to severe lack of water by the year 2025.
Inequalities in the availability of water - sometimes even
within a single country - are reflected in huge differences in consumption
levels. A person living in rural Madagascar uses 10 litres a day, the minimum
for survival, while a French person uses 150 litres and an American as many as
Scarcity is just one part of the problem. Water quality is also declining alarmingly. In some areas, contamination levels are so high that water can no longer be used even for industrial purposes. There are many reasons for this - untreated sewage, chemical waste, fuel leakages, dumped garbage, contamination of soil by chemicals used by farmers. The worldwide extent of such pollution is hard to assess because data are lacking for several countries. But some figures give an idea of the problem. It is thought for example that 90 per cent of waste water in developing countries is released without any kind of treatment.
Things are especially bad in cities, where water demand is exploding. For the first time in human history, there will soon be more people living in cities than in the countryside and so water consumption will continue to increase. Soaring urbanization will sharpen the rivalry between the different kinds of water users.
Curbing the explosion in demand
Today, farming uses 69 per cent of the water consumed in the world, industry 23 per cent and households 8 per cent. In developing countries, agriculture uses as much as 80 per cent. The needs of city-dwellers, industry and tourists are expected to increase rapidly, at least as much as the need to produce more farm products to feed the planet. The problem of increasing water supply has long been seen as a technical one, calling for technical solutions such as building more dams and desalination plants. Wild ideas like towing chunks of icebergs from the poles have even been mooted.
But today, technical solutions are reaching their limits. Economic and socio-ecological arguments are levelled against building new dams, for example: dams are costing more and more because the best sites have already been used, and they take millions of people out of their environment and upset ecosystems. As a result, twice as many dams were built on average between 1951 and 1977 than during the past decade, according to the US environmental research body Worldwatch Institute.
Hydrologists and engineers have less and less room for
manoeuvre, but a new consensus with new actors is taking shape. Since supply can
no longer be expanded - or only at prohibitive cost for many countries - the
explosion in demand must be curbed along with wasteful practices. An estimated
60 per cent of the water used in irrigation is lost through inefficient systems,
Economists have plunged into the debate on water and made quite a few waves. To obtain "rational use" of water, i.e. avoiding waste and maintaining quality, they say consumers must be made to pay for it. Out of the question, reply those in favour of free water, which some cultures regard as "a gift from heaven". And what about the poor, ask the champions of human rights and the right to water? Other important and prickly questions being asked by decision-makers are how to calculate the "real price" of water and who should organize its sale.
The state as mediator
The principle of free water is being challenged. For many
people, water has become a commodity to be bought and sold. But management of
this shared resource cannot be left exclusively to market forces. Many elements
of civil society - NGOs, researchers, community groups - are campaigning for
the cultural and social aspects of water management to be taken into account.
Even the World Bank, the main advocate of water privatization, is cautious on
this point. It recognizes the value of the partnerships between the public and
private sectors which have sprung up in recent years. Only the state seems to be
in a position to ensure that practices are fair and to mediate between the
parties involved - consumer groups, private firms and public bodies. At any
rate, water regulation and management systems need to be based on other than
purely financial criteria. If they aren't, hundreds of millions of people will
have no access to it.
- A person can survive for about a month without food, but only about a week without water.
- About 70 per cent of human skin consists of water.
- Women and children in most developing regions travel an average of 10 to 15 kilometres each day to get water.
- Some 34,000 people die a day from water-related diseases like diarrhoea and parasitic worms. This is the equivalent to casualties from 100 jumbo jets crashing every day!
- A person needs five litres of water a day for drinking and cooking and another 25 litres for personal hygiene.
- The average Canadian family uses 350 litres of water a day. In Africa, the average is 20 litres and in Europe, 165 litres.
- A dairy cow needs to drink about four litres of water a day to produce one litre of milk.
- A tomato is about 95 per cent water.
- About 9,400 litres of water are used to make four car tires.
- About 1.4 billion litres of water are needed to produce a day's supply of the world's newsprint.
Sources: International Development Initiative of McGill University, Canada; Saint Paul Water Utility, Minnesota, USA.
Desalinization, state of the art
irrigation systems, techniques to harvest fog-technological solutions like
these are widely hailed as the answer to water scarcity. But in searching for
the 'miracle' solution, hydrologists and policy-makers often lose sight of
the question: how can we use and safeguard this vital resource?
International Hydrological Programme (IHP) takes an interdisciplinary approach
to this question. On the one hand, IHP brings together scientists from 150
countries to develop global and regional assessments of water supplies and, for
example, inventories of groundwater contamination. At the same time, the
programme focuses on the cultural and socio-economic factors involved in
effective policy-making. For example, groundwater supplies in Gaza (Palestinian
Authority) are coming under serious strain, partly because of new business
investment in the area. IHP has a two-pronged approach. First, train and help
local hydrologists accurately assess the supplies. Second, work with government
officials to set up a licensing system for pumping groundwater.
|Lack of access to safe water and basic sanitation, by region, 1990-1996 (percent)||Periods of complete renewal of the earth's water resources|
|Region||People without access to safe water||People without access to basic sanitation||Kinds of water||Period of renewal|
|Arab States||21||30||Biological water||several hours|
|Sub-Saharan Africa||48||55||Atmospheric water||8 days|
|South-East Asia and the Pacific||35||45||Water in river channels||16 days|
|Latin America and the Caribbean||23||29||Soil moisture||1 year|
|East Asia||32||73||Water in swamps||5 years|
|East Asia (excluding China)||13||-||Water storages in lakes||17 years|
|South Asia||18||64||Groundwater||1 400 years|
|Developing countries||29||58||Mountain glaciers||1 600 years|
|Least developed countries||43||64||World ocean||2 500 years|
|Polar ice floes||9 700 years|
|Source: Human Development Report 1998, New York, UNDP||Source: World Water Balance and Water Resources of the Earth, Gidrometeoizdat, Leningrad, 1974 (in Russian)|