A review of 411 studies published since 1974 in Reviews of Geophysics finds global river sand extraction is far outpacing natural replenishment. In Vietnam's Mekong Delta, extraction rates run 11.8 times above the 6.18 megatons per year natural sediment replacement rate; between 2015 and 2022, approximately 366 million cubic metres were removed, causing a mean riverbed incision of 0.48 metres. More than 1,800 houses collapsed from riverbank erosion between 2018 and 2020 in Vietnam's Mekong section. At current rates, the Vietnamese Mekong could be depleted of sand by 2035. Other documented sites include China's Poyang Lake, Brazil's Paraná and Tocantins rivers, and the Seine in France, where early-20th-century mining pits persist as floodplain lakes.
Context
It is the same NTU Singapore study reported on 23 July, now providing the full journal publication details and additional site evidence from Poyang Lake, the Paraná, Tocantins, and the Seine.