Water Footprint? The indirect use of water in agriculture and industry

, by  Olivier Petitjean

Consumer goods and other industrial products, food and other agricultural products, energy etc.: there are few economic sectors that do not involve massive water consumption. All too often, industrial processes and economic models were developed without taking the need to conserve water into consideration.

Some sectors are well known for using a lot of water. This is particularly the case of irrigation in agriculture, household and leisure use such as car-washing, golf courses, swimming pools... We are less aware of the amounts of water used in agricultural or industrial production. In the countries of the South, agriculture often uses 80% of the available water resources. In Europe, on the other hand, industry consumes 54% of water resources, far ahead of agriculture, which uses 33%. The energy sector also uses enormous amounts of water (read Climate Change and the "Water-Energy Nexus").

With the impacts of climate change, consumers are starting to worry about their carbon footprint, that is to say the amount of greenhouse gas emissions involved in transport and products that they buy. In like manner, advertising the “water footprint” of all products sold can prove to be particularly edifying. Dutch researchers launched a Water Footprint network, dedicated to calculating the water footprint of various products, sectors and countries and promoting water saving. This information is available on their Internet site at http://www.waterfootprint.org.

Some agribusiness multinationals, especially Coca-Cola, whose impact on water resources has been seriously challenged in recent years, have recently launched marketing campaigns designed to "greenwash" their image in this area. Unilever announced that their tomato sauce for pasta now uses tomatoes from farmers who only use drip irrigation. This gesture is all the more significant as the company buys at least 7% of the global tomato production. In April 2009, the Finnish agribusiness, Raiso, became the first company in the sector to include the water footprint on the packaging of their products. The American chain, Wal-Mart, which is the biggest in the world, stated that they intend to develop a universal system of labelling for their products that states both the carbon and the water footprint. Coca-Cola now declares itself to be a “water-neutral” company (based on the expression “carbon-neutral”), in spite of their well-documented waste, on the pretext that they are involved in programmes restoring rivers or promoting rainwater harvesting. Although the concept of water footprint is relevant, that of “water neutral” appears more like a marketing gimmick, even more than that of “carbon-neutral”, which is already being seriously abused. Nevertheless most sectors are based on economic and industrial models that treat water as though it were a limitless resource – and the introduction of these new concepts does mark a limited form of progress.

The use of water in agriculture

Apart from the many other pitfalls, industrial agriculture uses a particularly high amount of water. It takes 180 litres to produce a single battery-farmed egg. Making one kilo of bread requires 1000 litres. One kilo of wheat needs 625 litres of water (555 million litres per hectare grown), one kilo of rice uses 3,000 litres and one kilo of meat requires even more (some sources talk of 25,000 litres, others 100,000 litres). The question of saving water are thus linked to our dietary regimes: according to the experts from the Worldwatch Institute, every 10 grammes of meat protein needs 5 times the amount of water required for 10 grammes of rice protein. If we compare the calories, the difference is even more remarkable, because it takes 20 times more water to produce 500 calories of meat than 500 calories of rice. It also takes 8 times more water to produce a given quantity of sugar compared with the same quantity of wheat.

Of course the amount of water involved in making a product depends on the conditions where it is grown: making a litre of orange juice involves 22 litres of water in Brazil, and 1000 in the United States, where orange groves have to be irrigated. But on the other hand transporting Brazilian orange juice to the markets of the North, with the operations involved (concentrating and deep-freezing it) also consumes a huge amount of water.

Fish farming also consumes a lot of water. Shrimp farming in India requires 50 times more water than growing rice. It involves intensive pumping of water that can lead to real quakes due to land caving in. This farming has become less profitable than rice farming, which has been abandoned in many regions.

The use of water in industry

Industry involves steam as well as using water to clean things, for air conditioning, cooling and freezing systems, and transport. Oil refineries, agribusiness, metallurgy, chemical industries as well as those manufacturing paper pulp and many others use vast quantities of water. The same holds true for mining activities, particularly gold mining.

It takes:
-  18 litres of water to make 1 lire of petrol
-  13 000 litres of water to make one 6 inch wafer of silicone, an element used in making many electronic devices
-  400,000 litres of water to make a car
-  750,000 litres of water to make 1 tonne of newspaper
-  8 tonnes of water per tonne of final product are required for treating sand and bitumen in Morocco or Canada.

This massive use of water by industry also leads to very severe pollution by heavy metals, solvents and polychloride biphenols, oils, over and above any possible recuperation that can be carried out.

In terms of saving water and developing a more rational use of the resource, industry is where the greatest efforts need to be made. The processes used are obviously the key. Between 1950 and 1990, industry in the United States reduced its water consumption by a third, although the volume of goods produced increased four-fold. Considerable progress has also been made in Sweden and Germany. The Worldwatch Institute quotes the instance of several companies that have launched ambitious water-saving plans. IBM is reputed to have saved 375 000 cubic meters of water in one year by more efficient use of water, and a further 315 000 by recycling. Columbia Steel economised 63 million cubic meters by rainwater harvesting and redesigning their cooling towers to recirculate water. As a final example, Unilever reduced their water consumption between 1998 and 2002 from 6.5 to 4.3 cubic litres per tonnes of products manufactured.

Nevertheless, specialists foresee that industrial use of water will double by 2025. The countries of the South that are in the process of industrialisation, need to make greater progress in saving water. In China, it takes between 23 and 56 cubic meters of water to make one tonne of steel, whereas the average in Germany, in the United States or in Japan is only 6 cubic meters.

To conclude, the quantitative aspects are of course decisive in evaluating the water footprint of a product or a process, but are not in themselves enough. It is also necessary to take at least the qualitative aspects into account (at least the degree of pollution of the waste water) and the geographical dimension (in which region of the world the water is being extracted and used). Water footprinting is an instrument that speaks for itself, but it is limited in what it can accomplish.

SOURCES
- Larbi Bouguerra, Les batailles de l’eau : pour un bien commun de l’humanité, Enjeux Planète, 2003.
- Erik Assadourian, Larbi Bouguerra, Collectif. La consommation assassine : Comment le mode de vie des uns ruine celui des autres, pistes pour une consommation responsable. Paris : Editions Charles Léopold Mayer, 2005. 261 p.
- Water Footprint Network : http://www.waterfootprint.org
- Josh Harkinson, «What’s your Water Footprint ?», Mother Jones, 2nd August 2009. http://www.motherjones.com/environm...

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