We’re running out of… sand?

Nature says that our need for silicon – the main substance in computer chips, as well as glass windows, bottles, and things like bricks and mortar – could actually threaten the world’s supply of usable sand:

Sand and gravel make up the most extracted group of materials, even exceeding fossil fuels. Urbanization and global population growth are fuelling an explosion in demand, especially in China, India and Africa. Roughly 32 billion to 50 billion tonnes are used globally each year, mainly for making concrete, glass and electronics. This exceeds the pace of natural renewal such that by mid-century, demand might outstrip supply.

For example, between 2006 and 2016, less than 4% of the 80 million tonnes of sediment that Singapore reported having imported from Cambodia was confirmed as exported by the latter. Illegal sand mining is rife in around 70 countries, and hundreds of people have reportedly been killed in battles over sand in the past decade in countries including India and Kenya, among them local citizens, police officers and government officials.

It is technically hard to quantify how sand moves or is deposited along rivers. In addition, many large rivers are remote, and politically and industrially sensitive issues of data access and transparency hamper reporting.

Many large river basins also span several countries, making it difficult to report and enforce regulations and international laws. For example, the Mekong River flows through China, Myanmar, Laos, Thailand, Cambodia and Vietnam.

In many countries, sand mining is unregulated and might involve local ‘sand mafias’. Methods of extraction range from dredging boats and suction pumping to digging with shovels and bare hands, both in daylight and during the night.

A global programme to gather and share data is imperative for quantifying the location and extent of sediment mining, as well as the natural variations in sand flux in the world’s rivers.