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Demand for sand is killing rivers in Africa
- payne92 9y agoDemand for sand (for concrete) is killing rivers... in Africa In the US, dredging rivers or land near a waterway is pretty restricted. Sand is typically mined from open pits, see: https://en.wikipedia.org/wiki/Sand_mining#United_States https://en.wikipedia.org/wiki/Sand_mining#United_States
- maxerickson 9y agoDoes anyone know how much of it comes down to geology? A lot of the accessible sand in the US is from glacial deposits. Wisconsin is mentioned in the Wikipedia article as having a boom in sand mining and the surface geology there is nearly entirely a result of glaciers.
- beex 9y agoThe situation is much the same[0] in many other parts of the world. [0]: http://www.smithsonianmag.com/science-nature/world-facing-global-sand-crisis-180964815/ http://www.smithsonianmag.com/science-nature/world-facing-gl...
- tryingagainbro 9y agoIsn't the river sand full of mud, in many cases? Can it really be washed that well?
- jaclaz 9y agoNot only it can be washed perfectly but river sand (and gravel) tend to be much better for concrete when compared to "crushed" aggregates. More or less the reason is that usually for a given size river ones are harder/more resistant, and have rounded edges (which also imply a bigger resistance) due to the cycles (wear, long time immersion, etc.) they were subjected to in the river. And, as a final advantage, concrete made with rounded aggregates is usually easier to pump.
- PhasmaFelis 9y agoMud is just soil in water, and drying and sieving soil is easy.
- dang 9y agoOk we've sent the title above to Africa.
- anotherbrownguy 9y agoOh so Africa is building long lasting concrete buildings and making life easier for everyone... something that most of the western world and a huge part of the developing world has already been using for a long time in the same way? No, let us tell you something much more important: how the freaking rivers are "dying". Environmentalism is anti-humanism.
- aluhut 9y agoObviously you didn't even read the damn article. What's wrong with you people? What are trying to achieve here?
- anotherbrownguy 9y ago>Obviously you didn't even read the damn article. I did. What is obvious is that you know nothing out of what is written selectively in an article in a vague way. If you think the sand illegally exported out of Africa is anywhere significant to the amount being consumed in Africa, you need to reconsider your sources of information.
- ezequiel-garzon 9y agoCan you share your sources then?
- pyre 9y agoSince you are so informed, could you please relate to us the numbers here? What are the numbers being exported vs. used domestically?
- PhasmaFelis 9y agoSo, you read the article after being called out for not reading the article and are now trying to selectively re-interpret it so you don't look silly?
- dang 9y ago
- zip1234 9y agoWhat about the Sahara desert? Seems like Africa has plenty of sand--why are they taking it out of rivers? Expensive to transport?
- gilleain 9y agoAddressed in the article: >The sand used for construction comes mainly from riverbeds and oceans. Desert sand, it turns out, is too smooth for the mix.
- s0rce 9y agoIt's actually quite striking if you handle Sahara desert sand its amazingly fine and smooth, I imagine other sand deserts where the sand is wind blown for eons is similarly smooth.
- pasta 9y agoA lot of desert sand can be compared to powder. So in most cases this cannot be used.
- microcolonel 9y agoMore specifically, they would have to go further east to get the coarser sand.
- EGreg 9y agoHere's an idea - why not require the companies to replace the river sand with desert sand after mining it? Have they tried to use desert sand in the river?
- zo1 9y agoThis is Africa you're talking about. As much as that sounds like noble and a good idea, convincing local communities and especially businesses here is not going to happen unfortunately. It's a consequence of being in the third world and having a "catch up at all costs" mentality. Besides, conservation and environmentalism just isn't as in-grained in most African cultures as it is in the west. Even if you convinced the local government of putting such a law on the books, the odds of them being able to track and enforce such a law is next to impossible. Maybe in more developed countries like South Africa or Namibia, but not in most of the others.
- stevenwoo 9y agoIndustrial scale mining often has unintended consequences - there was a long running sand operation in California that caused erosion all around it on the coast unless you asked the company that was doing it. http://www.mercurynews.com/2017/06/27/controversial-beachfront-sand-mining-operation-along-monterey-bay-to-close/ http://www.mercurynews.com/2017/06/27/controversial-beachfro...
- apthnz 9y agoIs there an alternative to using riverbed sand in concrete? Or an alternative to concrete for big buildings?
- lostlogin 9y agoCrushed concrete makes good concrete, but you'd still have to add sand.
- Animats 9y agoCrushing rocks down to sand is common. Here's the machinery.[1] The trick is to bang the rocks together. China seems to be making lots of sand for concrete. There are many manufacturers in China making rock crushers and sand-making machines.[2] China has plenty of mountain rock suitable for rock crushing. Here's a marketing paper on making sand, and what to make for making concrete.[3] [1] https://www.youtube.com/watch?v=1CpjRMICXNM https://www.youtube.com/watch?v=1CpjRMICXNM [2] https://www.alibaba.com/showroom/vsi-crusher.html https://www.alibaba.com/showroom/vsi-crusher.html [3] http://www.metso.com/showroom/construction/new-type-of-crushed-sand-to-replace-natural-sand-in-concrete-production/ http://www.metso.com/showroom/construction/new-type-of-crush...
- EGreg 9y agoWhy not use riverbed sand and replace it with other sand?
- iosDrone 9y agoThe New Yorker wrote a much better article about this months ago: https://www.newyorker.com/magazine/2017/05/29/the-world-is-running-out-of-sand https://www.newyorker.com/magazine/2017/05/29/the-world-is-r...
- martinpw 9y agoAlso an article here on impact of sand mining on rivers in India: https://www.nytimes.com/2017/03/01/magazine/sand-mining-india-how-to-steal-a-river.html https://www.nytimes.com/2017/03/01/magazine/sand-mining-indi...
- zghst 9y agoOh look, the 21st century looting of Africa for its resources. Just to think so many materials extracted from the continent and now sand. This poor continent keeps getting jacked.
- averagewall 9y agoIt's being used for local construction. Even if it wasn't, do you have the same sympathy for Australia which is a major source of many minerals? Continents aren't people. They don't have property rights. People do, and it's important for people to be able to exercise those rights to benefit their own lives.
- csense 9y agoGiven that silicon's the second most abundant element on Earth, it seems like it should be trivial to mine without causing environmental damage.
- s0rce 9y agoMost of the sand is mined to make concrete (cement + sand + rocks + water = concrete). I think they use much smaller amounts of much higher purity sand for making silicon.
- pcardh0 9y agoSounds like Kenya should takes some steps to reduce it's population growth. Do they really need another 48 million people? That is a lot of sand.
- deleted 9y ago[deleted]
- bhhaskin 9y agoIt is really crazy how much sand is needed for modern development. It is a key component in a ton of different things.
- kakwa_ 9y agoFor the French or German speakers here, there is an interesting 2013 Arte documentary on the subject: French: https://www.arte.tv/fr/videos/046598-000-A/le-sable-enquete-sur-une-disparition/ https://www.arte.tv/fr/videos/046598-000-A/le-sable-enquete-... German: https://www.arte.tv/de/videos/046598-000-A/sand-die-neue-umweltzeitbombe/ https://www.arte.tv/de/videos/046598-000-A/sand-die-neue-umw... (I didn't find an English version or English subtitles for it, sorry...) It's available until September 18.