“Sand is the invisible hero of our development” – rts.ch

Could the sandy beaches, jewels of the summer holidays, soon become a mirage of the past? Around the world, the majority of beaches recede inexorably, prey to the rise of waters that erodes the coasts, but not only. Because sand does not attract only vacationers: it is actually the most exploited natural resource in the world, behind water.

Construction of buildings, manufacture of glass, technologies and solar panels, or even oil extraction … Sand demand explodes around the world, while its reserves are annoying. Without him, no concrete: it takes 200 tonnes for a single house, 3000 tonnes for a hospital and 30,000 tonnes for a kilometer of highway.

Faced with this growing overexploitation, the UN launched in 2023 a global sand observatory, based in Geneva. This platform, the first of its kind, aims to quantify the extent of extractions and to document its consequences on ecosystems and local residents.

Pascal Peduzzi, director of Grid-Genève, the database on world resources affiliated to the UN Environment, was the guest of the last Geopolitis. For the environmental researcher and professor at the University of Geneva, the observation is unequivocal: “The exploitation of sand is a very important issue, and yet unknown. Sand is so omnipresent that it is not noted. It is the invisible hero of our development.”

Society, a sand castle?

From the manufacture of concrete to that of asphalt and glass, including cosmetic and electronic products, sand is omnipresent in our daily lives. Its extraction, whether artisanal or industrial, represents around 50 billion tonnes each year worldwide. A figure that has tripled in twenty years, while its resource takes thousands of years to regenerate. “Sand reproduces by erosion to geological scales. And we are used on an astronomical scale,” said Pascal Peduzzi.

If the majority of the sand is extracted to meet the needs within the same country, a part also feeds world trade. The first exporting country, the United States sold for nearly a billion dollars of sand in 2024, followed by the Netherlands (262 USD), Cambodia (USD 218), Germany (160 USD) and Belgium (112 USD). At the top of the importing countries are Singapore (USD 312), Canada (291 USD), China (291 USD) and Vietnam (225 USD).

A diplomatic weapon

Sand has become a strategic weapon. Singapore, for example, has enlarged its territory by 25% since the 1960s thanks to massive imports of sand from in particular from neighboring countries. A “polding” which is often done at the expense of supplier countries, including Indonesia, Malaysia, Thailand and Cambodia.

“When Singapore imports the sand of Indonesia, Thailand, Malaysia, or Cambodia, this affects local ecosystems, even pushes to disappear certain small islands, as is the case in Indonesia”, explains Pascal Peduzzi. “This can cause diplomatic tensions, because when you lose islands, you lose territorial water, and therefore exclusive economic zones.”

In other regions, such as the Southern China Sea, sand has become a strategic weapon to claim new territories by creating artificial islets. An approach disputed by the international community, underlines the researcher.

A black market that strikes the most vulnerable

The absence of international regulations promote the development of illegal traffic, especially in CAP-Vert, where many beaches turn into careers. Living in precariousness, many women have no choice but to harvest sand for a derisory income, around 25 Swiss francs per month.

These practices, which empty the beaches of their sand, affect other means of subsistence, such as fishing or collection of crabs, underlines Pascal Peduzzi: “Once the sand is removed, the crabs disappear, the fish are scarce, and the villagers are forced to leave their village for the cities.”

An ecological disaster announced

As the resource is scarce, extraction sites move towards ever more fragile environments. The seabed, the beds of rivers, rivers and the coasts are the most coveted. Because all the sands are not equal: that of the desert, shaped by the wind, is far too smooth and fine for the construction.

Biodiversity is the first affected, but also our adaptability in the face of climate change, alerts the researcher. “Sand is our first line of defense against storms and floods. It filters water and protects coastal groundwater from salt water infiltrations.”

In Vietnam, the exhaustion of reserves accelerates the erosion of the banks in the Mekong Delta, threatening to move hundreds of thousands of people due to the collapses. Beyond the extraction of sand, which changes rivers to the morphology, hydroelectric dams hold sediments, slowing their natural carriage and threatening the renewal of this resource. “Whether Vietnam likes it or not, there will be no more sand in ten years. These are the last grains of sand we extract,” said Nguyen Huu Thien, a specialist in the Mekong Delta.

Towards a global shortage?

Faced with the difficulty of supply, certain construction projects are stopped, as in Manila, in the Philippines, where the extension of an landing track was suspended for lack of sand. “We see that we are heading towards a shortage of sand. The small island countries, like the Maldives, are the first affected because they have very few materials,” notes Pascal Peduzzi.

In Europe, too, countries without mountains such as Belgium, Denmark and the Netherlands also lack resources. “It is estimated that there are sand for 80 years for Belgium, and a little less for the Netherlands,” added the professor.

Alternatives exist

Faced with its growing rarity, some companies bet on the manufacture of industrial sand, produced from crushed rocks or mining residues. This is particularly the case with China, in the middle of a real estate boom, where 80% of sand needs would be provided by this alternative.

To brake this overexploitation, Pascal Peduzzi recommends betting on recycling, extending the lifespan of buildings by renovation rather than demolition, and to use alternative materials. “Concrete is not the solution to everything, especially since cement production emits around 8% of greenhouse gas emissions. We can also build in straw or wood,” he said. In Switzerland, too, companies are studying the recovery of heavy metals and ashes from the incineration of waste to make it sand substitutes.

Rachel Barbara Häubi