The Water We Eat

Where does the food we eat come from? Is it good for me? And am I doing the right thing in consuming it? In a world of limited resources, questioning ourselves about our lifestyles and our consumption patterns is not only desirable but also necessary. For this reason, we have introduced here the concept of “virtual water”, namely the water required to produce the food, goods and services that we consume daily (Allan 1993, 1994, 1998). Thanks to the application of this concept, we will discover that we consume much more water than that we effectively see “running” before our eyes; we will highlight that the data showing Italian water consumption being 152 cubic litres a year per capita only reflect a partial consumption, referring only to the water used for our domestic purposes (drinking, cooking, washing, etc.).

The purpose of this chapter is to highlight the importance of food supply chains in understanding water security. Food supply chains are important because about 90 % of the water needed by an individual or a national economy is embedded in their food consumption. This water will be called food-water in this analysis. Food requires water to produce it. This water can be either green water—that is the water that is held in the soil profile after rainfall. Crops and vegetation can use this water for consumptive transpiration. Food-water can also be blue water, usually called freshwater. Such water can be diverted from rivers or pumped from groundwater. Globally, green water accounts for about 80 % of the water used for crop and livestock production. Over 20 % is blue water which is the water used consumptively in full and supplementary irrigation. The food supply chain is also important because farmers and other agents in this supply chain allocate and manage the vast volumes of water used consumptively. Farmers are helped by ag-industries which breed seeds and provide fertilizers, equipment and pesticides. All of these inputs plus science and many government subsidies have enabled farmers to increase their water productivity. Farmers manage about 90 % of the food-water resources in the food supply chain. The other 10 % of food-water is handled by corporations and other private sector entities that trade, transport, process and market food for consumers. The volumes of food-water in this non-farm part of the supply chain are therefore relatively small. (Note the analysis in this chapter does not address the water resources devoted to the production of fibre and energy. The author recognises the role of water in these economic activities but there is no space to address the nuances that these consumptive and non-consumptive demands place on the consumptive use of water.)

It is increasingly recognised that freshwater scarcity and pollution are to be understood in a global context. Local water depletion and pollution are often closely tied to the structure of the global economy. With increasing trade between nations and continents, water is more frequently used to produce export goods. International trade in commodities implies long-distance transfers of water in virtual form, where virtual water is understood as the volume of water that has been used to produce a commodity and that is thus virtually embedded in it. Knowledge about the virtual water flows entering and leaving a country can cast a completely new light on the actual water scarcity of a country. At the same time, it becomes increasingly relevant to consider the linkages between consumer goods and impacts on freshwater systems. This can improve our understanding of the processes that drive changes imposed on freshwater systems and help to develop policies of wise water governance. The water footprint is an innovative concept to analyse water consumption and pollution along supply chains, assess the sustainability of water use and explore where and how water use can best be reduced. This chapter shows how the water footprint concept can be used to understand the international dimension of water and to assess water use behind daily consumer goods. This chapter argues for greater product transparency, water footprint ceilings per river basin and water footprint benchmarks for water-intensive commodities.

Global environmental change (GEC) is the global change that human activity is causing in the natural systems of our wonderful planet. The international scientific community which is involved in GEC has been calling on, for years, the political and economic world to take action so that our society and our development models may finally start their journey on the road to global sustainability.

The terms virtual water and food security are increasingly used to enable us to focus on the need to conserve resources that pertain to the growing and eating of food. By understanding what water is required for food after the growing process, the complete role of water in food is revealed. That there is a looming crisis in the availability of food to many consumers is not denied. But as world famous economist Amartya Sen has written, there is sufficient food in the world today to feed everyone, and the problem is in the inequalities of distribution.

The idea of “zero km”, originally regarded the sale of cars (and still does today), referring to cars that for some reason is registered and number-plated but had never been used, with some disadvantages (less colour and optional choices available) but many advantages (immediate delivery and much lower prices than listed prices) for buyers. An alternate means to the traditional one of buying a car, but with substantial savings.

Food is the central pillar for the life of humankind; food is also an important element of our history and culture. In addition, food is an essential part of the environment and the places it originates from. Ludwig Andreas Feuerbach, a German philosopher, in one of his famous aphorism, expressed the idea that “We are what we eat”. If this concept is to be still considered valid, this means that the path we are undertaking is rather dramatic. In order to demonstrate that, it will be sufficient to articulate just a couple of considerations. The first is that, in Europe, 43 % of food waste is domestic waste. The second is that food is gradually becoming simply a commodity, that is, a good which must be traded at the lowest price, losing not only its economic value but also its nutritional, cultural, social and historical values.

Food represents 90 % of the water consumption of an individual and the agricultural sector uses on average 70 % of the freshwater withdrawn from surface and aquifers for irrigation purposes globally. From the perspective of a sustainable growth, oriented towards optimizing the use of green water and reducing that of blue water, i.e. irrigation waste and inefficiencies, it is essential to raise citizens’ awareness and promote more sustainable consumption. For this purpose, this contribution will discuss the possibility of guiding the commercial choices we, the citizens, make by means of a method for labelling water sustainability. This hypothesis of labelling provides “qualitative” information on the typology and origin of the water used to produce any type of food we consume.

In modern and industrialised societies, water—“conquered”, purified, channelled and distributed by means of technology and increasingly complex systems—seems to have lost its central role, not to mention the sacred role it historically held in shaping cultures and civilisation. Yet, over the last years, in different cases, water has returned once again to the attention of the public and become the focus of debate, particularly concerning the controversial question of the privatisation of water services.

Considering the assessment on water resources shown in Fig. 1 and a consumption of 92 m per capita annually for the period 1996–2007 (more than the 85 m average in the 27 EU countries), Italy seems to be highly vulnerable to any reduction in its water availability.

Food security, intended as the agricultural production capacity to satisfy the nutritional needs of the world’s population, is closely tied to water availability, the latter being essential for the production of any type of food. The water volume required to produce an established quantity of food is called the “virtual water content” and is the amount of water virtually embedded in the good, though not physically present in it. Italy is an exemplary case of high virtual water consumption and dependence on food imports. It is among the leading countries in the world for net virtual water importation, with a high per capita consumption and a persistent reduction in land surface used for agricultural production. Local contradictions arising from the global food supply model are the issue dealt with in this contribution, with particular reference to Italy.

Virtual water trade refers to the implicit content of water in the production of goods and services. When trade is undertaken, there is an implicit exchange of water. In countries where water is relatively scarce, water-intensive goods are expensive to produce, so that imports normally exceed exports and the economy virtually imports water. This paper provides some estimates of virtual water trade patterns in the Mediterranean, which is an area where water is scarce, unevenly distributed, and progressively insufficient because of climate change and reduced precipitation. We analyse two cases: the current virtual water trade structure, related to trade in agricultural goods, and a future scenario, simulated by means of a computable general equilibrium model, where reduced agricultural productivity, induced by lower water availability, is taken into account.

A limitation—but also an advantage, depending on the viewpoint—of economic evaluation is to refrain from any a priori criteria, value judgments and ethical parameters.

We realize that water is a resource only when it becomes scarce. Until now, the issue seemed to interest only the least fortunate countries in the world, but this could all change: firstly because “high-quality” water—non-polluted freshwater—represents only a small part of the planet’s reserves and secondly because of the increasing demand for water due to both the growing world population and more widespread wealth, which spurs more people in more countries to use (and waste) more water. Water use should be considered in both “real” terms (calculating the amount of water used for bathing, cooking, cleaning, etc.) and “virtual” terms (i.e., water footprint), estimating the total amount of water used in the entire life cycle of any product of service.

Every form of life on the Earth depends on water, and it is in water that billions of years ago the first life forms appeared. Also today, the almost 9 million living species found on our planet base their existence on water, a resource which is, therefore, not only essential but also very precious. Despite it being a renewable resource, it still, however, remains limited and vulnerable. Even if our planet viewed from afar appears as a prevalently blue sphere, with 71 % of the surface covered by water, we know very well that not all this water is actually available to humans. First of all, 97 % of the water is salt water found in the seas and oceans and only 3 % is freshwater, of which, however, most (68.6 %) is locked up in ice and glaciers, 30.1 % in groundwater and 1.3 % in surface water. The liquid water on the land surface is mainly found in the large lake basins, such as the North American Great Lakes or Lake Baikal in Russia, which contain 20.1 %, equal to 0.26 % of total freshwater, and in the swamps which make up 2.53 % (0.03 % of total freshwater). The atmosphere contains 0.04 % of total freshwater in the form of water vapour and the land 0.05 %, while the river systems contain a relatively low portion (0.006 %) (Fig. 1). Moreover, the geographic distribution of water is not homogenous—Brazil has 15 % of the global reserves and 64.4 % of the total water found on the Earth is found in only 13 countries (http://​ga.​water.​usgs.​gov/​edu/​earthwherewater.​html; Shiklomanov in Water in crisis: a guide to the world’s freshwater resources, Oxford University Press, Oxford, 1999). For this and for reasons of economic inequality, despite only 54 % of the world’s freshwater reserves presently used being accessible, a billion people do not have access to drinking water and 2 billion people do not have sufficient water for hygiene–sanitary services (Prüss-Üstün in Safe Water, Better Health, WHO, Geneva, 2008; IWMI in Water for Food Water for Life, Earthscan, USA, 2007).

The Italian “quality label” food product is synonymous with high quality and is very important from both an economic and cultural point of view.

The aim of this study was to calculate the water footprint (WF) of food products deriving from the processing of tomatoes by the Italian company Mutti SpA (Mutti hereafter), a market leader in the production of tomato paste, purée and pulp. Mutti, in collaboration with WWF Italy and the University of Tuscia, carried out the water consumption analysis of its production (the WF from tomato cultivation to the final derived products) and identified scenarios to reduce it. Mutti was one of the first companies in Italy and among the few in the world that has undertaken the WF calculation for its entire production chain, following the WF network methodology (www.​waterfootprint.​org). The calculation was based on a fine-tuned version of the existing, well-assessed and scientifically sound methodology, which takes into account two production stages (supply chain and operative phase) and all three elements of the WF—green, blue and grey. Mutti’s WF resulted in being approximately 393 m³/t, with the green, blue and grey elements representing 14, 33 and 53 % of the total, respectively. The findings also revealed that the WF of the supply chain covers 98 % of the total, with tomato cultivation playing the predominant role (84 %). Where the three elements are concerned, the grey part represents more than a half of the footprint along the entire supply chain. During the operative phase in the factory, the only contributing element is the blue water (2 %). Potential reductions assuming a higher irrigation efficiency and/or more controlled fertiliser use were also simulated showing that, if uniformly optimising irrigation and fertilisation across farms providing tomatoes to Mutti, the reduction potential could fluctuate between 2.5 and 5 %. These results reinforce the hypothesis that a nearly real-time monitoring of the soil and/or crop conditions is a useful strategy to support a reasonable and realistic commitment to WF reduction.