On this day of “overshoot”, the bad news is linked. And even the grain of sand has something to worry about. Every year on Earth, we consume 18 kilos of sand per inhabitant. 50 billion tons and if we add the consumption of gravel. There is enough to build a wall 27 meters high and wide each year that would circle the earth at the equator.
>> “Overshoot Day”: humanity has consumed all the resources that nature takes a year to produce and renew
Globally, this consumption of sand and aggregates has tripled in twenty years because we use it in the construction of buildings and roads. For example, it takes 200 tons of sand to build a house and 30,000 tons for each kilometer of highway. Sand is also needed to make glass, electronic components or even tires. This sand is taken both from quarries, rivers or seabed and beaches.
On the other hand, desert sand cannot be used to make concrete because the grains of sand are too small and too round for the mixture to hold. In a report published this year, United Nations experts once again warned that this banal material must now be treated as a strategic resource. Because the environment is paying too much for this uncontrolled appetite for sand. If the stocks run out, it takes tens of thousands of years for nature to produce this sand, through a phenomenon of erosion and wear of rocks and soils.
The beaches are therefore at risk of disappearing, because under the effect of this extraction and the rise in sea level, three quarters of the world’s beaches are receding. Sand extraction also leads to soil modification, biodiversity, shoreline subsidence, and pollution of groundwater.
Obviously this consumption of sand accompanies the urbanization and development of certain parts of the world, and we will not be able to do without it, but the UN recommends clearer international regulations.
And as for energy, sobriety is part of the solutions: to save sand, it would be necessary for example to use more wood for construction, to renovate buildings when possible instead of destroying them. Above all, old construction materials should be recycled as much as possible by crushing them.