Demand for 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 main driver of this crisis is breakneck urbanization. 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.
But sand isn’t only used for buildings and infrastructure – increasingly, it is also used to manufacture the very land beneath their feet. From California to Hong Kong, ever-larger and more powerful dredging ships vacuum up millions of tonnes of sand from the sea floor each year, piling it up in coastal areas to create land where there was none before. Dubai’s palm-tree shaped islands are perhaps the most famous artificial land masses that have been built from scratch in recent years, but they have plenty of company.
Lagos, the largest city in Nigeria, is adding a 2,400-acre (9.7 sq km) urban extension to its Atlantic shoreline. China, the fourth-largest nation on Earth in terms of naturally occurring land, has added hundreds of miles to its coast, and built entire islands to host luxury resorts.
This new real estate is valuable, but it often incurs steep costs. Ocean dredging has damaged coral reefs in Kenya, the Persian Gulf and Florida. It tears up marine habitat and muddies waters with sand plumes that can affect aquatic life far from the original site. Fishermen in Malaysia and Cambodia have seen their livelihoods decimated by dredging. In China, land reclamation has wiped out coastal wetlands, annihilated habitats for fish and shorebirds, and increased water pollution.
And then there’s Singapore, a world leader in land reclamation. To create more space for its nearly six million residents, the jam-packed city-state has built out its territory with an additional 50 sq miles (130 sq km) of land over the past 40 years, almost all of it with sand imported from other countries. The collateral environmental damage has been so extreme that neighboring Indonesia, Malaysia, Vietnam, and Cambodia have all restricted exports of sand to Singapore.
Mining sand to use in concrete and other industrial purposes is, if anything, even more destructive. Sand for construction is most often mined from rivers. It’s easy to pull the grains up with suction pumps or even buckets, and easy to transport once you’ve got a full boatload. But dredging a riverbed can destroy the habitat occupied by bottom-dwelling organisms. The churned-up sediment can cloud the water, suffocating fish and blocking the sunlight that sustains underwater vegetation.
River sand mining is also contributing to the slow-motion disappearance of Vietnam’s Mekong Delta. The area is home to 20 million people and source of half of all the country’s food and much of the rice that feeds the rest of South East Asia. Climate-change-induced sea level rise is one reason the delta is losing the equivalent of one and a half football fields of land every day.
Sand extraction from rivers has also caused untold millions of dollars in damage to infrastructure around the world. The stirred-up sediment clogs water supply equipment. And removing all that material from river banks leaves the foundations of bridges exposed and unsupported. In Ghana, sand miners have dug up so much ground that they have dangerously exposed the foundations of hillside buildings, which are at risk of collapse.
Demand for high-purity silica sands, which are used to make glass as well as high-tech products like solar panels and computer chips, is also soaring. America’s surging fracking industry also needs the extra-durable high-purity grains. The result: acres of farmlands and forests in rural Wisconsin, which happens to have a lot of those precious sands, are being torn up.
In many Western countries, river sand mining has already been largely phased out. Getting the rest of the world to follow suit will be tough, though. “Preventing or reducing damage to rivers will require the construction industry to be weaned off river sourced aggregate,” says a recent report on the global sand industry. “This type of societal shift is similar to that required to address climate change, and will necessitate changes in the way that sand and river are perceived, and cities are designed and constructed.”
At present, no one even knows exactly how much sand is being pulled out of the earth, nor where, nor under what conditions. Much of it is undocumented. “We just know,” says Bendixen, “that the more people there are, the more sand we need.”
