Water is embedded in and enriches nearly everything, including food. Agriculture accounts for a staggering 92 per cent of the rain, ground and surface water that people consume, most of it pumped for irrigation to produce cereal grains, meat and milk. This crucial reliance on water faces big challenges; a fifth of the world’s rapidly rising population is already battling water scarcity, and farming must compete against the ever-growing demands of cities and industrial development.
While our need for water is universal, the many ways we overuse it and the walloping water footprints created by our relationships with food are too frequently unseen and ignored. The colossal scale of transportation of agricultural products, our insatiable appetite for meat and the amount of food we waste are exacerbating water deficits, destabilizing our ability to feed humanity.
There is no easy fix to such complex, deeply ingrained problems. To begin the repair process, we must rethink how we feed ourselves, and we’ll need participation from governments, communities and individuals. Smaller water footprints and food systems that nourish rather than deplete their inhabitants are not only a possibility, but also an urgent necessity.
Food waste is water waste
Figures are kilocalories per capita per day, by region.
Source: Reducing Food Loss and Waste
(World Resources Institute, 2014 unep.org
At the annual World Water Week forum in Stockholm in August 2012, one of the many takeaways for convened experts was the fact that food waste is a major global threat to water reserves. Between one-third and half of the planet’s food never reaches a mouth, meaning that the water used to grow it is literally thrown out. In developed countries, retailers and consumers drive the waste problem; the US, for example, throws out 30 per cent of its food, which represents about 40 billion litres of water used for irrigation annually. In less developed regions like sub-Saharan Africa and Southeast Asia, improper storage infrastructure and inefficient harvesting and transportation of food plagues the producer side of the supply chain.
One-fifth of global water consumption moves around the world, embedded in commodities. The food trade comprises most of this virtual water, yet water-scarcity issues don’t often dictate the industry’s approach to distribution. A 2013 report by the Proceedings of the National Academy of Sciences suggests that virtual water trade is unsustainable because import-dependent countries use it to thrive on the resources of others, causing their consumers to surpass local usage thresholds. For example, a water-scarce country (such as Egypt or Singapore) importing water-intensive foods (such as grains and meat) doesn’t actually address a supply deficit in any meaningful way. The longer-term danger is that as water-abundant countries face growing populations, they are projected to export less virtual water elsewhere.
Virtual water balances by country, 1996 to 2005
Measured in gigametres cubed (Gm3) per year. The largest gross virtual water flows more than 15 Gm3 per year are indicated by blue arrows. Source: The Water Footprint of Humanity (Hoekstra & Mekonnen, PNAS, 2012). View the larger map.
Water at steak
The 1995 and 2005 numbers are meat consumption in kg/person
per year. Developed countries include former centrally planned
Source: The State of Food and Agriculture (2009) fao.org
The rise of affluent lifestyles has shifted diets toward animal products and amplified stress on our limited water supplies. Between 2000 and 2050, annual meat consumption is projected to rise from 37 kg to 52 kg per person in developed nations and from 27 kg to 44 kg in developing nations, and the planet’s dairy consumption will nearly double to more than a billion tonnes. In turn, 80 per cent of the nearly 500 million additional tonnes of maize produced in 2050 will be used as livestock fodder to feed those larger appetites for animal products, as will the additional water needed to grow it. Ominously, a 2012 study by the Stockholm International Water Institute warned that caloric intake from animal sources must decrease to five per cent of the average person’s daily consumption or there will not be enough water to support the coming decades of global population growth.
The China example
To combat a yearly water deficit that could reach 400 billion m3 by 2050, the Chinese government invested 345.2-billion Yuan [$57.1-billion] in conservation initiatives in 2011. The country’s water-depleted north already exports 52 billion m3 of virtual water annually to southern regions. This situation is further complicated by the contentious South-North Water Transfer Project, which will divert another 45 billion m3 from the Yangtze River to the Yellow River Basin in the north. The country’s water scarcity is also exacerbated by food waste – an estimated 50 million tonnes of grain are thrown out every year. Activists and NGOs launched the “Clean Your Plate” campaign in 2013, and China’s most famous agricultural scientist, Yuan Longping, has controversially encouraged the government to criminalize food wastage. China’s imports of virtual water doubled between 2001 and 2007, 90 per cent of it embedded in soy used for animal feed. Chinese meat consumption has also quadrupled in the last 30 years.