Sand: We consume too much of it

Sand consumption has exceeded critical levels, and global demand has exceeded the natural self-reproduction capacity of this important natural resource. Relationship of the United Nations Environment Programme (UNEP) on the sand — in particular “Sand and Sustainability: 10 Strategic Recommendations to Avert a Crisis” (2022) and subsequent updates — essentially says that we are facing a real global sand management crisis (“Our use of sand has us with our backs to the wall” is written in the UNEP Report).

But why has sand consumption become unsustainable? Let's start with the assumption that sand, after water, is the most extracted resource on the planet: we consume approximately 50 billion tons of it each year. A lot of it is needed for urbanization, that is, to build buildings and infrastructure, and we have less and less of it considering the enormous consumption throughout the entire construction industry. Just two examples: concrete is made up of 80 percent sand, while the percentage rises to 94 percent in the case ofasphalt.

Sand is formed over geological timescales (hundreds of thousands of years), but we use it much faster than it regenerates → this creates the so-calledor “sand gap”. And what is causing the "global sand crisis"? Again, UNEP's response is very clear:

river and coastal erosion
loss of natural defenses against storms and rising seas
salinization of aquifers
destruction of habitat (fish, birds, coastal and river ecosystems)

As for possible solutions, UNEP indicates the most important ones, namely:

reduce demand (build less and better)
recycle construction and demolition materials
use alternatives (crushed rock, industrial waste materials)
prohibit or limit extraction in sensitive areas (beaches, active ecosystems)
introduce international rules and monitoring.

Of these solutions, the most sustainable is certainly the one that involves the recycling of building materials.

The recycling of construction and demolition materials (often called C&D waste) is already a widespread practice in many countries, which should be developed and encouraged everywhere.

This is how it works when a building is demolished:

the “clean” materials (concrete, bricks, stones) are separated
the problematic ones are removed (wood, plastic, metals, insulation, plaster)
the inert material (cement, bricks, stones) is taken to specialized plants
crushed into smaller pieces by machinery
After crushing, dust and impurities are removed and the different grain sizes (fine, medium, coarse) are separated.

Recycled aggregates can be used as new concrete, replacing some of the virgin sand and gravel, and can be used to make road surfaces, prefabricated bricks and blocks, and low-emission cement.

Regarding UNEP's latest recommendation, regarding sand consumption controls, it must be said that the situation varies greatly from country to country. Among the countries where it is most critical are India and Indonesia, as well as some African countries: Illegal sand mining is widespread here and is controlled by organized crime. In India, for example, the phenomenon is defined as “sand mafia”, and illegal sand mining from rivers is widespread in several states (e.g. Uttar Pradesh, Bihar, Maharashtra, Tamil Nadu).

Sand is in high demand for rapidly growing urban construction, and in some areas, criminal gangs control quarries or stretches of river, bribe public officials working in the sector, issue death threats to journalists who investigate the phenomenon, and manage the entire supply chain for the illegal transport and sale of sand.

We consume too much sand

Read also:

Want to see a selection of our news?