We all need it. No one has invented a mechanism for plants, animals, and humans to live without it. However, water is one of the resources that has been mostly wasted and neglected by humans: it receives waste from toilets, chemicals from industry, and thousands of other pollutants around the world.
Water covers 70.8% of the earth’s surface, but only 2.5% of all the water on the planet is freshwater, that is, water fit for consumption. Of this, most are inaccessible in glaciers, at the poles, etc., so we only have 0.5% available for consumption, which is groundwater or surface water. There are currently 6,000 million people on Earth, of which about 20% live in 50 countries that lack this vital liquid and, at the current rate of consumption, it will soon become (has already become) a problem capable of generating armed conflicts and will affect (is already affecting) the future of the biological diversity of many areas of the planet.
Today, water can no longer be seen as an inexhaustible and abundant resource. By his actions, man is increasingly reducing the amount of this liquid that can be useful to him. And despite the imminent scarcity, water has continued to be used in different industries that account for a large percentage of the world’s human water consumption. As an example, only in the state of California in the United States, the average water use per person is 1500 gallons per day, this is associated with the consumption of meat and other products of daily use (,Fulton et al., 2012).
What Do We Use The Most Water For?
Industries need huge amounts of water to operate and maintain themselves. Without them, most human activity would grind to a halt, as a large number of the products and objects we use in our daily lives could not be produced. In some cases, the water used becomes part of the final product.
In other cases, the water is used to cool the various machines used. Very often, water is used for sanitary purposes, such as sanitizing or cleaning facilities, even a lot of water is used to extract fossil fuels from the earth (,EPA, 2011; ,Geetanjali et al., 2015). In conclusion, industrial water consumption receives daily large amounts of this precious commodity for its proper functioning.
Globally, the proportion of water abstraction is approximately 69% agricultural, 19% industrial, and 12% municipal. This calculation is given from the total global withdrawal for each use; and is strongly influenced by a few countries that have very high water withdrawals compared to others. On the other hand, when the proportions of water abstracted by use are calculated for each country, and the global average is elaborated, it is shown that “for a given country” the proportion of abstraction is 59%, 23%, and 18%, respectively.
The industry is one of the main drivers of economic growth and development. Worldwide, about 19% of the water withdrawn is used in industry. Of this amount, more than half is used in thermal power plants for their cooling processes. Among the largest consumers of water under this heading are petroleum plants, the metal, paper, wood, food processing, and manufacturing industries. It is estimated that global water demand for the manufacturing industry will increase 400% from 2000 to 2050, centered in emerging economies.
The livestock industry is associated with high consumption of water resources. To this must be added the fact that, nowadays, meat consumption is much higher than necessary. From a health point of view, it is six times higher than recommended.
Globally, agriculture uses 70% of freshwater sources, and there are even sources that claim the use of 80-90% of water (,USDA, 2021). This figure is so high because of the amount of land that must be irrigated to make agriculture viable, to increase and improve yields. It is estimated that approximately 34 to 76 trillion gallons of water are used annually (,USGS, 2009; ,Pimentel et al., 2004). But also, agricultural activities pollute large amounts of water. Industrial livestock production directly pollutes groundwater, surface water, and rivers through the management of livestock waste, and indirectly through the use of pesticides and feed additives (hormones, antibiotics, etc.) for livestock. In addition, as we have already seen, much of this land is wasted growing feed for livestock instead of food for people. The water used on these lands – consumed directly by livestock – represents another source of waste of the resource.
There is a considerable discrepancy in the exact amount of water required for meat production purposes. It has been calculated that to produce 1 kg of potatoes 500 lt of water is needed, 900 lt for 1 kg of wheat, 3,500 lt for 1 kg of chicken meat (edible), and 18,000 lt for 1 kg of beef. (,Robbins, n.d.) Others say that to produce 1 kg. of wheat requires 120 lt. of water, and for 1 kg. of beef, 3,700 lt. of water. It is interesting to take a closer look at these figures: whether the most radical or the most conservative estimate, beef production represents an outrageous expenditure of water compared to the production of vegetables or cereals.
Producing 1 kg. of meat requires 2,800 kcal and 174 g. of protein. Producing 1 kg. of wheat requires 3,300 kcal and 110 g. of protein (of which 100 are for the human digestibility adjustment). 1 kg. of beef requires 3,700 lt. of water and 1 kg. of wheat requires 120 lt. If we look at these figures in perspective, we see that while wheat production gives us an average of 27.5 kcal for each liter of water used, beef provides only 0.76 kcal per liter. This means that (based on the most conservative data) producing beef requires 36 times more water per calorie than wheat. When we do the same calculation for digestible protein, wheat is 18 times more water-efficient than beef.
From these calculations, producing one kilogram of beef uses as much water as:
– 40 sinks
– 300 toilet flushes
– 100 times the amount of drinking water per person as calculated by UNESCO.
In addition to meat, the production of other foods of animal origin also represents a high water consumption. Producing 1 kg of chicken eggs requires 900 lt, and twice as much for 1 kg of cheese (,EWG, 2011; ,WEF, 2015) and 265 lt of water for 1 lt of milk (,Hoekstra et al., 2008).
Since a large percentage of crops feed animals in developing countries, this lost water does not come from our reserves, but from the share of countries where water is scarcer. A problem of social justice and inequity.