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0 pointsjmkd5y ago0 comments

Dams all over the world capture sediment. This not only reduces their capacity, it deprives downstream areas of sediment needed for natural habitat, to fertilise wetlands and to buffer against oceanic incursion.

The Sanmenxia Dam in China lost 17% of its capacity in the first 18 months of its operation due to sediment accumulation [1]

Countless other dams have already been dismantled due to sediment build up, and many more will follow, considering that around 19000 large dams worldwide are over 50 years old [2]

[1] https://en.wikipedia.org/wiki/Sanmenxia_Dam [2] https://e360.yale.edu/features/water-warning-the-looming-thr...

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belval5y ago

Honestly this sounds like mostly poor engineering planification and analysis. If you look at the dams with a lot of sediment it's mostly in South-East Asia and Africa while Europe/North America have little of it.

jmkdOP5y ago

Asia's rivers have by far the highest level of sediment of any continent [1] meanwhile the US has quietly destroyed over 1000 dysfunctional dams in the post war period [2]

[1] https://agupubs.onlinelibrary.wiley.com/doi/epdf/10.1029/WR0...

[2] https://www.pbs.org/wgbh/nova/article/dam-removals/

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