Barcelona Field Studies Centre

Water: A rare and precious resource

The UNESCO Courier 1999

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 425.
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, for example.
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.


Sharper Vision

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? UNESCO's 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.
By joining forces with the World Water Council, an international think-tank on hydrological issues, IHP is now hosting one of the most ambitious projects in the field: World Water Vision. Hundreds of thousands of hydrologists, policy-makers, farmers, business leaders and ordinary citizens will take part in public consultations to develop regional scenarios as to how key issues like contamination will evolve in the next 25 years.

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)