Water World

Soon there will be no more water. When the water runs out, so will our food.

A lot of talk of how much weight of feed goes in to produce per kilogram of the meat products we eat, but the water we use is often overlooked. Approximately 3.8tn cubic metres of water is used by humans annually with 70% being consumed by the global agriculture sector.

All the food you can think of requires water — from crop and livestock production, inland fisheries or aquaculture, forest products, requires water. Water that comes in the form of rain and moisture stored in soils (green water) or from withdrawals in watercourses, wetlands, lakes and aquifers (blue water). 70% of the blue water withdrawals go towards irrigation. Irrigated agriculture represents 20% of the total cultivated land but contributes 40% of the total food produced worldwide.

It takes about 1500 litres of water to produce 1 kilogram of wheat, and it takes an astounding 10 times more to produce the same amount of beef.

A kilo of bananas will set you back roughly 790 litres. An egg 196 litres. 250 millilitres of milk takes roughly a thousand times more water to produce it (255 litres). Chocolate is the worst offender (vegetarians take note) costing 17 196 litres of water to produce a single kilo.

Source: Global Food. Waste not, Want not.

The world is thirsty because it is hungry. As population increases more stress is placed on finite resources like water. There are alternatives for energy but there is no alternative for water. To feed more people (world population set to hit 9 billion by 2050) farmers must grow more crop. Farmers get their irrigation water either from rivers or from underground aquifers.

An aquifer is an underground layer of water-bearing permeable rock from which groundwater can be extracted using a water well. More and more we are seeing countries drill into their aquifers and over-pump their waters. Depleting aquifers to grow food is the definition of the term unsustainable.

Thirst of Arabia: Greening the desert

Saudi Arabia from above looked like a vast sprawling desert dotted with specks of lush green fields. Wheatfields that produces the grain to feed its populus. The water to irrigate those fields did not come from rivers. Of course, in the desert, there are no rivers. What they were doing was pumping "fossil" water. Water stored underground since the last ice age — at a time when the middle east region could have been described as "wet". An arid Saudi Arabian landscape was turned into the sixth largest wheat exporting country.

In 2008, Saudi Arabia announced that production of wheat would soon stop in the coming years — abandoning a 30 year-old program to grow wheat that achieved self-sufficiency at the cost of water — a scarce commodity in a desert region. By 2016 Saudi Arabia has said it will rely solely on imports for all its wheat, rice, corn and barley needs to feed its population of 30 million people.

A 2004 report from the School of African and Oriental Studies described Saudi Arabia's project to make the "deserts bloom" as a waste of money and water on a grand scale. A nation and a generation with newly found oil wealth ushered in an era of unsustainable environmental politics that resulted in Saudi Arabia teetering on the edge. So much so that Saudi Arabia has now reached into the headwaters of the great Nile to quench its thirst.

Claims this year that 18 other countries, containing around half of the world's current population, are now over-pumping their underground water tables to a point where they cannot be replenished. China and India will soon face this problem. Syria, Iraq and Yemen are also on the list.

At the root of Saudi Arabia's clash with water unsustainability was population growth. Between 1973 and 1992, increased wealth and improved living conditions led to an increase in population by about 250%.

The world is seeing the collision between population growth and water supply. Each passing day now brings more people to feed and less irrigation water with which to feed them. And each day the margin between food consumption and survival is getting thinner.

By 2050, 70% more food will be needed to feed the expanded population. As developing country populations get wealthier diets will undoubtedly shift — to one that looks more and more like the western diet. Meat consumption in particular is expected to rise from 37 kg per person per year at the turn of the millenium to 52 kg in 2050.

Agriculture is not the only strain on our watery world. Population increase and economic growth will ensure the competition for scarce resources will continue. In the future,wars will not be ignited by the assassination of kings and dignitaries, but by the scramble for water.

References:

Lester Brown "The real threat to our future is peak water" The Guardian July 6, 2013

Elie Elhadj "Camels Don't Fly, Deserts Don't Bloom: an Assessment of Saudi Arabia's Experiment in Desert Agriculture" SOAS/KCL Water Research Group, Occasional Paper No 48, School of Oriental and African Studies (SOAS)/King's College London, University of London, May 2004

Institute of Mechanical Engineers "Global Food Report: Waste not, Want not" January, 2013

Image credits:

Image by MSVG (via Flickr)