[hobs]

Did you read the article?

They are discussing offshoring this sand to other countries that can afford it, not to build useful African structures. An argument from "The world has already been using this for a long time" could be used for any number of grotesque and terrible acts (and has) so I will ignore that part.

The main complaint about the "rivers dying" is that it has a outsized impact on the poor who use those rivers for food and water (which is no longer available and which is no longer captured, respectively.)

While some people truly believe in the preservation of nature over humans, most of us "Environmentalists" want to save the environment because of the direct and indirect human suffering inappropriate exploitation of our shared resources cause.

[Spooky23]

Theres a lot of domestic construction going on in African countries. That growth is all using modern methods, which means lots and lots of pumped concrete.