After water, sand is the material people take from the planet most. Every tower, road and window starts as sand, and in many rivers and seas we now dig it out faster than nature puts it back.
50 bntonnes of sand used every year
Enough to build a wall 27 metres wide and 27 metres high around the equator every year. Demand rose about fivefold from 1970 to 2020. UNEP, Sand and Sustainability, 2022 & 2026
01 · The scale
Not every grain counts
To a geologist, "sand" is a narrow size band: grains from 0.0625 to 2 millimetres across. Builders need a narrower slice still: angular grains from rivers, lakes, coasts and the seabed.
Sand · 0.0625–2 mm
Clay<0.004 mm
Silt0.004–0.06
Sand0.06–2 mm
Granule2–4
Pebble4–64 mm
Wentworth grain-size scale (log axis, 0.001–64 mm). Light → dark = fine → coarse.
60–75%
of the volume of concrete is aggregate, meaning sand and gravel. (Portland Cement Association)
Too smooth
Desert sand is rounded by the wind and is generally unsuitable for concrete, so deserts don't solve the shortage. (UNEP, 2019)
#2
Sand is the most-exploited resource on Earth after water. (UNEP, 2022)
02 · The trend
Fivefold in fifty years
Global sand demand went from 9.6 billion tonnes in 1970 to about 50 billion in 2020, growing about 3.2% a year as cities filled up.
Solid dots are reported values (UNEP 2026). The dashed curve between them is an illustrative smooth interpolation, not annual data. Next: UNEP projects sand demand for buildings alone could rise up to 45% by 2060.
03 · The comparison
Taking more than rivers bring
Sand is made slowly, over hundreds of thousands of years, by rock wearing down and rivers carrying it to the coast. Today's extraction runs ahead of that supply.
Worldwide · billion tonnes per year
All sand & gravel used by people≈50
Sediment rivers naturally deliver to coasts10–16
Dredged from seas & coasts4–8 (avg 6)
Hatched = upper end of range. UNEP Marine Sand Watch, 2023.
Mekong River · million tonnes per year
Sand mined from the river50
Sand the river carries into the delta6.2
That is roughly 8× more taken than arrives. The authors' models show that dredging just 2 m into the bed can destabilise riverbanks, where millions of people live.
Hackney et al., Nature Sustainability, 2020.
04 · The map
A country grown from imported sand
Singapore has added about a quarter to its land area since the 1960s, mostly with sand brought in from its neighbours.
581.5 → 725.7 km²
Singapore's land area, 1960 to 2019. The government targets about 766 km² by 2030. (Singapore Government, SG101)
517 million t
of sand imported over 20 years, the most of any country. Neighbours' reported exports to Singapore came to 637 million t, a 120 million t gap. (UNEP, 2014)
+25%
more land than in the 1960s, built largely on dredged marine sand.
05 · The stakes
Who pays for missing sand
Sand holds up deltas, beaches, fisheries and coastal economies. Take too much and the land and the jobs on it wash away.
2.3 bn
people
depend on small-scale fisheries that rely heavily on sandy ecosystems. (UNEP, 2026)
750 m+
coastal tourists a year
visit coasts and beaches. Coastal tourism brings in more than US$1.5 trillion. (UNEP, 2026)
+45%
by 2060
Possible rise in sand demand for buildings alone as cities keep growing. (UNEP, 2026)
What you can do · Why it matters
Treat sand as a resource, not dirt
Renovate before rebuilding. A building kept standing is sand nobody has to dig up again.
Ask for recycled aggregate. Crushed concrete and manufactured sand from quarry rock can replace part of the river sand in a mix.
Back sand traceability. UNEP's 2026 report sets out 24 actions, including knowing where sand comes from and limiting extraction to what rivers replace.
Watch your local river. Unlicensed dredging lowers riverbeds and undermines banks and bridges. Report it.