Alice DEBIASI
December 2010 - January 2011

 

It’s well-known: fresh water may well be a renewable resource, but the pressures caused to it (increase in the worldwide population, in the standard of living, in industrial and agricultural production) are so great that it may disappear one day. And yet, water is an essential production factor for ensuring the success of business activities. Water is therefore on the way to becoming an issue to be managed for private organisations, just like carbon or biodiversity. This is why the water footprint, a recent, complex and still mysterious tool, which is just beginning to be developed within firms, is arousing interest and curiosity from firms and will, in the end, become a concept that is as well-known and used as the carbon balance or LCA.

 

Water footprint: a recent yet historical tool

Although the water footprint is still little-known, virtual water, its ancestor, is even more so. Virtual water is a concept created at the start of the nineties through the work of John Anthony Allan. This academic, surprised to see that none of the forecast water wars were actually taking place, ended up discovering that the States, instead of fighting each other for this vital but unfairly available resource, made up for their shortage in fresh water by using virtual water. Through worldwide trade, at the same time as buying food and products, the importing country buys the water required to produce them, which it is lacking itself. This water is virtual water.
The concept gave rise to a real craze in the academic world which saw it as an opportunity to reduce, or even wipe out, the problems caused by water. Their work led to the creation of the water footprint, the State being the subject of the study. It involves assessing the value of all of the direct and indirect water used for producing the goods and services consumed by the inhabitants of the country in question and the water used for manufacturing the products to be exported (internal water footprint), alongside the water imported through products in order to support national consumption (external water footprint). The water footprint is made up of three “types” of water:

• Blue water = the volume of water taken from the surface of waterways (rivers, lakes, …) or in the underground waters (water tables, fossil aquifers, …).
• Grey water = the volume of water that would need to be used in order to dilute the commonly-used pollutants, until the legal limits are reached (drinking water standards, WHO standard …). Grey water is still undergoing intense research in order to obtain a more precise indicator. Although dissolution is a functional approach, it does not enable to take into consideration a certain number of factors (mixture of pollutants, life-cycle of the products, …) and raises issues regarding the reference standards to be used.
• Green water = the volume of water consumed or evaporated by plants during the natural evapotranspiration phenomenon.

Although green water is particularly useful for the States (territorial management and national agricultural policies), it is however more an indicator to be used with caution than a tool for firms, as it is difficult for them to take action by using it. The possible options for reducing the green water will consist in misleading solutions, such as increasing farming irrigation or increasing farming yield. Indeed, these choices may lead to increasing the blue water, a type of water that is much more important for a company as it may be controlled and is completely attributable to the activity of the firm. Not all water footprints should be reduced.

Water footprint: a tool for firms

The water footprint, applied first of all to the States, was soon passed on to the firms, and although this transition may still require methodological adaptations, the principle remains the same: assessing the value of all of the water consumed directly and indirectly when manufacturing a product or providing a service.
Assessing the value of the water footprint of products or services enables firms to have a precise estimation of their level of dependence on this resource. Once this first stage is complete, the outcome obtained enables to implement the actions required for a sustainable management of the resource for the company. The water footprint may also become a factor in helping with decision-making by informing the deciders of the product, system or raw material with the highest performance in terms of water. It is therefore a question of providing the firms with a tool that is capable of managing this new environmental issue in the best possible way.

Although the methodology shall continue to develop, the water footprint is a tool that is already used by firms. It has been taken on by fans of LCA in order to make it more relevant, to increase its level of accuracy and to make it easier to read. In parallel, ISO is drafting a new ISO / PWI* 14046 standard which is to “establish the principles, requirements and guidelines for assessing the water footprint of the products, processes and organisations, on the basis of the assessment indications of the value of the impact, as given in ISO 14044”.
The speed with which the environmental world has claimed this new concept and the need felt by the firms to have an additional tool available to them in order to manage this new issue at stake, lead to believe that the water footprint has a bright future in front of it.

*PWI: Preliminary Work Item

Alice DEBIASI
December 2010 - January 2011