Lakes, forests and wetlands… Water is the lifeblood of all ecosystems on which our future food security depends.
Yet, water scarcity gets more and more pressing for sustainable development as the world’s population continues to grow, diets evolve, living standards increase, and the effects of climate change widespread.
Since 2012, the World Economic Forum lists water crises as one of the top five risks to the global economy, with 40% of the planet facing potential freshwater deficits by 2030, according to projections by the United Nations. To many of us, the amount of water required to make everything we buy, use, and eat is still pretty vague. Yet, just as consumers have embraced new sustainable habits and driven “eco-wakening” in other parts of the economy, we could help drive a reckoning around water conservation.
The concepts of water footprint and virtual water
The carbon and water footprint concepts were introduced a decade ago. These two environmental indicators complement each other, addressing respectively climate change and freshwater scarcity. On one hand, our water footprint is the amount of water we consume in our daily life, including the water used to grow the food we eat, to produce the energy we use and for all of the products in our daily life – books, music, house, appliances, car, furniture and clothes. It is a multidimensional indicator, not only referring to a water volume used, but also making explicit where the water footprint is located, what source of water is used and when. If it comes from a place where water is already scarce, the consequences can be significant and require action.
Virtual water on the other hand, also called “embedded water” or “indirect water,” is the water “hidden” in the products, services or processes we buy and use every day. Although it often goes unseen by the end-user of a product or service, that water has been consumed throughout the value chain, which makes creation of that product or service possible*. Take, for example, a microchip manufacturer who uses highly distilled water in its operations. When taken together, all the steps in which direct water is used add up to the total water required to get a finished product to consumers. That total can be considered virtual water content.
“The interest in the water footprint is rooted in the recognition that human impacts on freshwater systems can ultimately be linked to human consumption, and that issues like water shortages and pollution can be better understood and addressed by considering production and supply chains as a whole,” says Professor Arjen Y. Hoekstra, creator of the water footprint concept.
Simply put, virtual water specifically refers to the amount of embedded water in a commodity required to produce, package and ship the commodity to consumers, while water footprint illustrates the total consumption of water as measured for the individual consumer, community, nation or business.
Much more than what we just see flowing from the tap
Did you know there is the same amount on earth today as there was in the origins? As our population grows, and pollution develops, pressure on our limited water supply is increasing. In our global economy, the global water footprint is estimated to be 9 trillion tons per year, that’s almost 300,000 tons of water a second! Among that volume, agricultural production takes the largest share, accounting for 92%, industrial production contributes 4.4% and domestic water supply contributes 3.6%.
Everything we use or eat has a water footprint, sometimes processed close to where we live but often, in river basins far away. As a result, each of us consumes on average as much as 1,300 gallons of water every day (ranging from 400 to 2,600 gallons per day, depending where on location and diet)*. A hamburger, for example, will “cost” you 660 gallons of water. Take a bowl of pasta: some of the steps to consider in terms of virtual water include: water to grow the wheat; water to produce the fuel for machines to harvest the wheat and transport the pasta to the store; and water to create the electricity for processing the wheat into flour and pasta. Foods that tend to have smaller water footprints are plant-based foods like fruits, vegetables, grains, beans and lentils. When it comes to a freshwater resource, it tends to be more efficient to eat plant products rather than animal products.
Educating on how to be more thoughtful about water use
As children grow and take part in the world around them, it is crucial they comprehend how vital water is to their bodies and environment. And most of all, how they can do their part to protect it! As parents and educators, we are tasked with this increasingly important job of teaching the younger generation about ecology, and water conservation is a growing part of this curriculum. Do your kids know how many gallons of water are required for them to take a bath or a shower, wash their clothes, or brush their teeth? How is their water use impacted by their food choices, shopping habits and how can it cause them to use more water than they may realize? There are lots of fun, engaging, and creative ways they can learn with us how to shift habits and use this precious resource wisely and sustainably!
- Water Footprint Assessment Manual: Setting the Global Standard: Read the report
Institute for Water Education / Unesco – “National water footprint accounts: The green, blue and grey water footprint of production and consumption” https://waterfootprint.org/media/downloads/Report50-NationalWaterFootprints-Vol1.pdf