French engineer Georges Mougin has a big idea. He wants to go to Antarctica, tie a big rope around a six-million-ton iceberg, drag it back to Africa and melt it into fresh, drinkable water.
They don't talk about whether they'll try to cover it to reduce the melting. I'd have thought that would be an important question.
How about pumping seawater into a desert and let the sand filter out the salt, then pump up drinking water from below? Wonder if that could work. Would probably be a long line, and maybe the sand wouldn't get out all the salt. Perhaps too there'd be too big a loss of water over the process. And probably the energy expense would be huge, as well as the environmental impact.
This article says that salt is very hard to separate from water, so maybe sand simply wouldn't do the trick. Well, I was just spitballing.
Trying googling for this, I found this small-scale, but smart method.