By Vince Beiser
It may be little more than grains of weathered rock, and can be found in deserts and on beaches around the world, but sand is also the world’s second most consumed natural resource.
A South African entrepreneur shot dead in September. Two Indian villagers killed in a gun battle in August. A Mexican environmental activist murdered in June.
Though separated by thousands of miles, these killings share an unlikely cause. They are some of the latest casualties in a growing wave of violence sparked by the struggle for one of the 21st Century’s most important, but least appreciated, commodities: ordinary sand.
Trivial though it may seem, sand is a critical ingredient of our lives. It is the primary raw material that modern cities are made from. The concrete used to construct shopping malls, offices, and apartment blocks, along with the asphalt we use to build roads connecting them, are largely just sand and gravel glued together. The glass in every window, windshield, and smart phone screen is made of melted-down sand. And even the silicon chips inside our phones and computers – along with virtually every other piece of electronic equipment in your home – are made from sand.
And where is the problem with that, you might ask? Our planet is covered in it. Huge deserts from the Sahara to Arizona have billowing dunes of the stuff. Beaches on coastlines around the world are lined with sand. We can even buy bags of it at our local hardware shop for a fistful of small change.
But believe it or not, the world is facing a shortage of sand. How can we possibly be running low on a substance found in virtually every country on earth and that seems essentially limitless?
Sand, however, is the most-consumed natural resource on the planet besides water. People use some 50 billion tonnes of “aggregate” – the industry term for sand and gravel, which tend to be found together – every year. That’s more than enough to blanket the entire United Kingdom.
The problem lies in the type of sand we are using. Desert sand is largely useless to us. The overwhelming bulk of the sand we harvest goes to make concrete, and for that purpose, desert sand grains are the wrong shape. Eroded by wind rather than water, they are too smooth and rounded to lock together to form stable concrete.
The sand we need is the more angular stuff found in the beds, banks, and floodplains of rivers, as well as in lakes and on the seashore. The demand for that material is so intense that around the world, riverbeds and beaches are being stripped bare, and farmlands and forests torn up to get at the precious grains. And in a growing number of countries, criminal gangs have moved in to the trade, spawning an often lethal black market in sand.
“The issue of sand comes as a surprise to many, but it shouldn’t,” says Pascal Peduzzi, a researcher with the United Nations Environment Programme. “We cannot extract 50 billion tonnes per year of any material without leading to massive impacts on the planet and thus on people’s lives.”
The main driver of this crisis is breakneck urbanisation. Every year there are more and more people on the planet, with an ever growing number of them moving from the rural countryside into cities, especially in the developing world. Across Asia, Africa, and Latin America, cities are expanding at a pace and on a scale far greater than any time in human history.
The number of people living in urban areas has more than quadrupled since 1950 to some 4.2 billion today, and the United Nations predicts another 2.5 billion will join them in the next three decades. That’s the equivalent of adding eight cities the size of New York every single year.