Some six billion tonnes of sand are torn from the oceans each year, an exploitation at the limit of what is sustainable and with dramatic consequences for the environment and marine biodiversity, the UN warned on Tuesday 5 September. This is the first time that the United Nations has managed to make such an estimate, thanks to artificial intelligence and the automatic system for identifying ships to locate them and analyze their movements and activities around the world. .
The analysis, launched by the scientific division of the United Nations Environment Program (UNEP), is only in its infancy, and only 50% of ships are currently being monitored. Thus, artisanal or small-scale mining along shallow coasts cannot yet be detected. But the UN estimates that of the 50 billion tons of sand and gravel that humanity uses each year, between four and eight billion come from the seas and oceans. This represents six billion tonnes on average each year, “the equivalent of more than one million trucks per day or two kilograms per day and per person”, explained the director of the data analysis center for the UNEP, Pascal Peduzzi, at a press conference.
gigantic proportions
“Schools, hospitals, roads, hydroelectric dams, wind turbines, solar panels, glass… in fact our whole society depends on sand as a building material”, argued Pascal Peduzzi. Sand also plays a crucial role for the environment, but it is also a material that many countries will need to protect themselves against rising sea levels, he concluded. The UN hopes to be able to publish the figures for the period 2020-2023 again this year. But the data show that this activity continues to grow and “is beginning to take on gigantic proportions”, said Mr. Peduzzi, stressing that in comparison the rivers transport them, in the seas and oceans between 10 and 16 billion tons. sediment each year.
“If we use a lot of sand, at some point it exceeds the capacity of the system to provide that sand,” he said. Extractor vessels are like “vacuum cleaners” that “grind the seabed” and “sterilize” it, causing ocean microorganisms to disappear and endangering biodiversity and fish resources, according to the expert. The North Sea, Southeast Asia and the East Coast of the United States are among the places where marine dredging activities are the most intense.
China, Netherlands, United States and Belgium
Another expert, Arnaud Vander Velpen, told him that the countries with the largest fleets of extractor vessels are China, the Netherlands, the United States and Belgium. Belgium, which extracts sand from the North Sea, “already knows that it still only has 80 years of volume available if it continues at the current rate”, noted Pascal Peduzzi. Beyond the figures, the UN hopes to have discussions with countries and companies in the sector so that the latter are more respectful of the environment by improving their extraction practices.
According to Arnaud Vander Velpen, only a small number of countries know what their marine sand resources are. Furthermore, international practices and regulatory frameworks vary considerably. Some countries – including Indonesia, Thailand, Malaysia, Vietnam and Cambodia – have for the past two decades banned the export of sea sand, while others have no legislation or effective monitoring program.
UNEP calls on the international community to develop international regulations to, among other things, improve dredging techniques and recommends banning the extraction of sand from beaches because of its importance for coastal resilience, the environment and economy. He also advocates a strategic recognition of sand so that it is no longer considered a common material that humanity could dispose of at will.