Launched at the UN Commission on Sustainable Development the report, Let it reign: The new water paradigm for global food security, warns that unless steps are taken to improve the way water is managed, twice the world’s current water consumption will be needed to feed a global population of 9 billion by 2050.

While international commitments hope to halve the number of people facing hunger in the world, the report’s authors ask: where is the water needed to grow the food going to come from?

“The world needs more food and consumption is moving towards more water-intensive items and less healthy diets. Irrigation can only partly satisfy the thirst for expanded future food production, and agricultural land is shrinking,” said Professor Jan Lundquist of Linkoping University and one of the report’s authors. “Global food security in the future requires a new water management approach today.”

Demand for food is likely to increase by 50% every generation. How big that increase will ultimately be, however, depends on the purchasing power of consumers. At present, more and more people are opting for a high-calorie intake diet. If this becomes the social norm for all of humanity, the increased pressure on natural resources, especially water, will be dramatic.

This is because agriculture is such a high water-consuming activity. In developing countries, the report says, agriculture accounts for 70-90% of available supplies. Already, in large parts of the world, water is the most limited and most uncertain resource, both in food production and for different ecosystems.

A fundamental consequence for crops grown in the open landscape is that large quantities of water evaporate back to the atmosphere from vegetation and soil, particularly in hot climate regions. The report also points out the disparately consumption of water involved in producing meat, an increasingly popular dish as affluence grows.

It takes 550 litres to produce enough flour for one loaf of bread. By comparison, it takes 1,500 litres of water to produce just 100 grams of beef.

Around the world there is a drastic reduction in the levels of water in rivers and lakes, as well as sinking groundwater levels.

However, the report sees this as a double-sided problem. In the affluent parts of the world, supermarkets are overflowing with produce from all over the world – much of it thrown away as waste. In these parts, food shortage is not the problem. Over-consumption leading to obesity is more the norm.

Interestingly enough, this over-consumption can lead to similar problems as under-consumption – they both reduce the chances of productive and healthy lives.

But, it is in the richer, over-consuming parts of the world that can exercise real choice, by not buying food that is produced in such a resource hungry manner.

The world is rapidly converting nature to agricultural land to meet growing demands, draining rivers of all water to produce food, and polluting water with pesticides and fertiliser. The old questions about how to produce more food without further undermining our environment still lingers, but a new question emerges: How can food demand and intake be equitable, sound and within the earth’s biological production potential?

Here, the report says, it is not farmers, governments and technicians who need to puzzle over technical solutions, it is the consumer who faces fundamental choices. Either in favour of good, local, healthy food produced in a sustainable manner, or resource heavy, water draining produce.

The report calls for more information to be made available to consumers on the way food is produced and what social and environmental costs it brings. Choices in the local supermarket, it reminds us, do not just affect our individual lifestyles. They have profound impacts on the lives of communities and their environments, in far away parts of the world.

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