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Water Resources

3. How much freshwater is available in different countries?

    The Food and Agricultural Organization (FAO) of the United Nations has developed and maintains a widely used database on water known as AQUASTAT. Based on the figures it contains, the FAO has compiled an index of how much water is, in theory available and, more particularly, for each person, on average, in each country. This index takes into account runoff and groundwater replenished by precipitation, water that flows into and out of a country, and water shared with other countries.

    The average amount of water available per person varies from less than 50 m3 per year in parts of the Middle East to over 100 000 m3 per year in humid and sparsely populated areas.

    Though the database has become a common reference tool, it has some limitations. Estimates indicate only the theoretical maximum amount available for a country and may overestimate the amount actually available. For instance, about a quarter of the runoff in the world each year (which would figure as such in the FAO’s index) is actually floodwater, which is unusable. Another drawback is that the index gives annual and country-wide, but not seasonal or local figures, which are both important. It gives information by country, but not by climatic region within countries. It does not give figures for “green water”, which sustains natural systems and supports farming, or for water from other sources such as non-renewable water from underground; nor does it take full account of how much water actually leaves a country. Finally, the index does not distinguish between different socio-economic groups in terms of who has access to water, even though differential access is common (e.g., slum dwellers have inadequate access to clean water).

    Recently, a more accurate picture has been produced of how many people, and where, are living in areas suffering severe water shortages. The higher level of detail allows us to see differences within a country, and suggests that about three times more people than was previously thought are living in areas with severe water shortages. More...

    Select a country to view the amount of water available in 2005:

    Or view the entire table of 193 countries

    For more detailed past and present country by country data consult the AQUASTAT main country database

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