Posted on May 6, 2021
Two geologists walk into a bar. The first one says to the bartender, “You know, soon there’s going to be a shortage of sand.” The bartender looks up, waiting for the punchline. The second geologist says, “He’s not kidding and that’s not a joke.”
Conjure up images of the Sahara, Gobi deserts or the dunes of Tottori — there are plenty that work; roughly one-third of the Earth’s surface is officially classified as desert, much of it sandy — and it’s hard to believe that worries about a sand shortage aren’t an inside joke among environment researchers.
The cause of the concern is sand is the second-most consumed natural resource in the world, surpassed only by water. It is estimated — and the numbers are very rough — that some 50 billion tons of aggregate (the industry term for sand, gravel and other materials used in construction) are consumed each year for construction. That’s enough to build a wall 27 meters high and 27 meters wide around the world at the equator.
Sand provides the foundation of modern society — and that isn’t a metaphor. In addition to construction projects, sand is used for land reclamation — airport runways in Haneda and Kansai, islands in the South China Sea, the expansion of Singapore, or Dubai’s Palm Islands. It is melted down to make glass in windows, computer screens and mobile phones. Sand is the critical component of the silicon chips that power a wired society.
But the surge in infrastructure spending that will accompany the post-pandemic economic recovery should turn a crescendo of warnings into a genuine crisis, destroying both ecosystems and the societies that depend on them. Sizzling demand will encourage the usual bad behaviors that accompany exploding markets: environmental degradation, forced labor and criminal profiteering.
There are many piecemeal solutions to these problems, but there is virtual unanimity that we don’t even have a grip on the scale of the problem. For a start, the world needs an accurate assessment of the amounts extracted and where. Only then can we get serious about saving our sand.
No one can say with precision how much sand is consumed each year but we know two things: Use is growing — it has tripled in the 21st century — and use far exceeds the rate at which sand is created. That is hard to believe given the vast expanses of desert that cover the globe and which, we are told, are expanding annually.
But all sand is not created equal. Desert sand is created by wind-driven erosion and the resulting grains are smooth and rounded. To be useful for construction, sand should be angular and better able to lock together. That sand is created by water and is found in and extracted from rivers, seabeds, coastlines and quarries.
Driving demand is urbanization. The extraordinary economic successes of the developing world have attracted billions of people to cities — the number of urban residents has quadrupled since 1950 to reach 4.2 billion people and will grow by another 2.5 billion by 2050. Housing them, transporting them and serving them demands sand; for example, 1 km of highway requires 30,000 tons of sand.
It is estimated that China used more sand in the second decade of this century than the United States consumed in the entire 20th century. (Another study concludes it took China just two years to top 100 years of U.S. consumption.) In India, use of construction sand has more than tripled in 20 years. Singapore has built an additional 130 sq km of land to accommodate its growth over the last 40 years.
Consumption will accelerate as governments resume infrastructure projects that were postponed because of the COVID-19 pandemic, such as China’s Belt and Road Initiative, or are initiated to spark recoveries or fill newly recognized gaps, as in the U.S.
Statistics are uncertain because much of the sand mined is used locally and informally. Nevertheless, the market is global. Most of Singapore’s sand comes from neighboring countries, for which the collateral environmental damage has been so bad that they now ban exports. There is so much construction in the Middle East that countries like Dubai import sand from Australia.
Demand like that guarantees that there is money to be made, and sure enough, there are organized crime groups running mining ventures around the world. According to Arpita Bisht, a researcher at Erasmus University in the Netherlands, the industry is “plagued by rampant illegality, a strong black market and intense violence.”
A United Nations Environment Program (UNEP) report found “sand mafias” in Cambodia, China, India, Kenya, Mexico, Sierra Leone and Vietnam, whose behavior is like that of criminals everywhere. They pay police to turn a blind eye to their activities. They intimidate journalists and activists who try to shine a light on their crimes — and deaths are common. They exploit their workers, many of whom are children, forcing them to work long hours for little or no pay, with no safety precautions in conditions that are dangerous and leave long-lasting effects.
The UNEP report highlights “a growing trend of irresponsible and illegal extraction … (that) makes this a sustainability challenge of significant proportions.” In Morocco, for example, half the sand mined, some 10 million cubic meters a year, is extracted illegally. It’s estimated that 24 Indonesian islands disappeared between 2005 and 2014 because of sand extraction and another 80 are under threat.
Sand extracted from the Mekong River — 55 million tons a year in 2011 according to one study — and dams built upstream are slowly strangling that waterway. Channels in the Mekong delta in Vietnam are reckoned to have deepened 1.4 meter in a decade, prompting fears that half the delta, home to 20 million people and the source of much of Southeast Asia’s rice and aquatic spawning grounds, could disappear by the next century.
Dredging from ocean sand mining damages reefs and creates sand plumes that profoundly affect aquatic life. Cloudy water kills micro-organisms. Fish and other types of marine life suffocate. River mining undermines river banks and erodes beaches. Muddied waters kill fish and birds, dirties rivers and reduces water for crops. Pascal Peduzzi, head of the UNEP Global Resource Information Database, warned that “In some places, … it’s led to total ecological disaster.”
There is much to be done. The first step is getting a grip on the problem. The U.N. took a key step in 2019, when it first officially recognized aggregate mining as a problem that required international study and a coordinated response. The British think tank Chatham House helped raise awareness with a recent conference that addressed this issue. The prospect of a construction boom has further concentrated attention.
Once the scale of the problem is understood, standards need to be set to guide extraction. Alternatives to sand need to be developed. Recycling is one option. While Japan is (in)famous for its readiness to pour concrete, it banned marine and sand mining in 1990 and has developed alternative methods of producing fine sand by crushing quarry waste which is used in construction projects.
As Pascal Peduzzi argued two years ago, “We cannot extract 50 billion tons per year of any material without leading to massive impacts on the planet and thus on people’s lives.” And for sure, it is no joke.