Built on Sand
Date Posted: July 23, 2019
Posted In: Ideas,
From 99Percent Invisible: Sand is so tiny and ubiquitous that it’s easy to take for granted. But in his book The World in a Grain, author Vince Beiser traces the history of sand, exploring how it fundamentally shaped the world as we know it. “Sand is actually the most important solid substance on Earth,” he argues. “It’s the literal foundation of modern civilization.”
Wherever we go, we’re surrounded by sand. It’s in the floors beneath us, walls around us and ceilings above us, plus the sidewalks and roads we use to get from place to place. Sand is a key ingredient in concrete, asphalt, and glass, not to mention the silicon chips inside our phones and computers. It is an essential component of modern life as we know it, yet, strangely enough, we are starting to run out.
“There’s a lot of sand in the world,” explains Beiser. “It’s actually the most abundant thing on the planet. But we are also using way more of it than ever before in human history. We use more sand than any other natural resource in the world except for air and water.” Humans use about 50 billion tons of sand each year. Of course, there is still plenty of it around, but not all sand is created equal, and much of it is effectively useless for construction. When it comes to desert sand, “the actual grains are shaped differently than sand grains that you find at the bottom of rivers or on beaches,” says Beiser. “It’s been eroded by wind rather than water over thousands and millions of years,” rendering it too round and smooth to be useful in creating robust concrete, which requires rough sand and aggregate to form proper bonds.
For much of metropolitan history, cities were built of materials like stone, brick, and wood. Ancient Romans developed a form of concrete, but after the fall of the Roman Empire, the technology was largely forgotten about. We stopped building with concrete until the 20th century, when a new development, reinforced concrete, took the world by storm. It became seen as a miracle material—malleable and durable, strong, and fireproof. Modern engineers appreciated its physical properties, using it to create roads, bridges and dams. Modernist architects, meanwhile, made use of these advantages, too, but also played with the flexible forms the material enabled, creating structures like the Guggenheim in New York and the Sydney Opera House.
But all that concrete requires sand, and the demand for sand has gotten so intense it’s causing problems. In some places good sand has become so scarce that the industry has begun to attract organized crime. People kill and get killed over sand. And the rate of urban development, particularly in Africa and Asia, means that that demand is not going away any time soon. “So to give you an idea,” says Beiser, “in 1950 there were about 750 million people worldwide living in cities. Today, there are more than 4 billion people living in cities … and tens of millions more pouring in every year. We’re adding the equivalent of eight New York Cities to the world every single year.”