Sand extraction for use in construction globally has led to pollution, flooding, lowering of water aquifers and worsening drought occurrence, according to the UN.
In a report UN Environment said demand for sand and gravel stood at 40-50bn tonnes per year but there was low awareness of the impact caused by extraction methods.
International trade in sand and gravel is forecast to rise at 5.5% a year due to urbanisation and infrastructure development trends. Demand for sand has increased threefold over the last two decades.
The report said extraction was causing rivers and coastlines to erode, damaging river and marine environments, while “science and policies to support responsible consumption and extraction are lagging behind”.
“For one of the most traded commodities on the planet, there is very low general awareness about widespread extraction impacts,” said the report.
The UN said “sand mafias”, who extract the commodity illegally, were “thriving”, giving the example of Morocco, where 10m cubic meters of sand a year is dug illegally from the coast to build hotels and roads.
The report said China and India headed a list of “critical hotspots”, which also included Cambodia, Vietnam, Indonesia, Sierra Leone, Kenya, Tanzania and Colombia.
“Avoidance of irresponsible sand consumption must be designed-in to our infrastructure projects, construction projects and industrial products from the beginning,” said the report.
“Some countries already have high aggregate recycling rates because of virgin aggregates costs (Germany recycles 87% of its waste aggregates).
“However, it is the intersection of materials cost minimisation pressures in construction projects and locally-available waste streams that seems to create some key enabling conditions for substitution away from primary aggregates.”
The report called for more transparent sand and gravel supply chains, legal frameworks, stronger standards, and more recycling and substitution.
Joyce Msuya, acting executive director of UN Environment, said: “We are spending our sand ‘budget’ faster than we can produce it responsibly. By improving the governance of global sand resources, we can better manage this critical resource sustainably and truly demonstrate that infrastructure and nature can go hand in hand.”