Global Water Distribution
The distribution of the world’s water resources is very uneven: nine countries - Brazil, Russia, China, Canada, Indonesia, the U.S., India, Colombia and the Democratic Republic of Congo - enjoy access to 60% of the global freshwater resources.Water is abundant in the far north and the far south, meaning North America, Northern Europe and Northern Asia, the south of South America as well as New Zealand. The tropics are also generally rich in water, for example the
Amazonian basin and parts of the Congo basin.
In contrast, many parts of Africa, the Middle East, Central Asia, the west of North America and Australia are very water scarce. Consequently, the calculated average amount of accessible renewable freshwater per person and year varies dramatically:
- each Canadian has access to an average of 87,000 m³,
- each Chinese to 2,100 m³ and
- each Jordanian to only 120 m³.
These amounts include water used for agricultural irrigation.
Similarly, water quality varies also greatly at a global scale. For instance, water borne diseases are rather widely spread in Africa, while tap water in Central and Western Europe is of very high quality and suitable for drinking.
Does Water have a Footprint?
Worldwide water consumption has increased roughly sixfold between 1930 and 2000. The increase is due to the tripling of the world population and the doubling of the average per capita water consumption. Economic growth, urbanization and the massively rising number of people pursuing modern, resource-intensive lifestyles result in an additional increase of 64 billion m³ of freshwater each year.
Food production consumes by far the most water globally. The use of tap water accounts for only a small share of the water footprint, also in industrialized countries. The term “water footprint” was coined in 2002 by Arjen Hoekstra from the UNESCO Institute for Water Education. It takes into account the overall amount of water used in production processes – be it of food or of industrial products.
All these products contain so-called "virtual water" which describes the total volume of water used in the entire production chain, for example:
- 15,000 l for 1kg of beef,
- 1,300 l for 1kg of grain,
- 3,400 l for 1kg of rice and
- 6,000 l for a pair of jeans.
Taking into account “virtual water”, the average daily consumption per capita in Germany is 4,000 – 5,000 l. In comparison, the average use of a Chinese is around 2,000 l per day. The concept of virtual water is also applied in calculating import and export flows.
The concept of “virtual water” draws attention to the vast amounts of water we use for products in our daily life. However, 140 l of water to produce a cup of coffee – is this a lot or not? To guide our daily consumption choices, the concept is too complex and too limited at the same time. It is not sufficient to only consider the amount of water used for producing everyday products.
It makes quite a difference, for example, whether a pair of jeans and the cotton it is made from have been produced in a water scarce or water rich region. Or whether wetland area is being drained for the irrigation of orange tree plantations.
The social dimension should also be borne in mind. Many products that contain “virtual water” produce income and thereby economic prosperity and security for parts of the population in newly industrialized and developing countries. Finally, the ecologic impact of a product does not stop with the water used but also comprises issues such as CO2 emissions, energy use and the use of pesticides.
Buying water-friendly also means buying climate-friendly: seasonal and local food products where possible, moderate meat consumption, avoiding excessive packaging and throwing away less food, critically questioning the need to buy new clothes and household goods and opting for the most durable products.