Yogita Limaye investigates concerns that vital reserves of sand may be running out.

Yogita Limaye investigates concerns, highlighted in a United Nations study, that vitally important reserves of sand are running out, with serious consequences for human society and the planet.

Sand is quite literally the foundation of our society. Nearly everything we build in the modern world is made from concrete and its most integral component is sand. But the resource takes thousands of years to form and we're consuming it faster than it is being replenished.

UK Geologist Andrew Bloodworth says that much of the way we're mining sand is unsustainable. Around the world we're taking from active ecosystems - river beds, beaches and the sea floor increasing the risk of droughts, coastal flooding and causing damage to fisheries.

In Mumbai, Yogita meets environmental campaigner Sumaira Abdulali who has been threatened and violently attacked for her work in highlighting sand mining. In many parts of the country, sand mining without a permit is now illegal - but she says that has only pushed the practice underground creating 'sand mafias'.

In Goa, Professor Purnanand Savoikar is working to reduce our dependence on sand. He's researching ways to make concrete by partially replacing sand with recycled waste plastic. Professor John Orr from the University of Bath says 10% of sand can be saved in this way if applied globally. He says there is a huge amount of wastage in the way we design buildings.

Pascal Peduzzi of the United Nations Environment Programme believes doing nothing is not an option - only a wholesale change in attitudes can prevent irreversible damage to the planet.

Producer: Matt Willis
A 7digital production for BBC Radio 4.