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Comment by notepad0x90

2 days ago

that's very insightful. But if I can dive a bit deeper, why can't desalination be made at a grander scale? why aren't desalination plants trying to fill up artificial lakes for example, where those lakes are also being topped-up with reused potables. Would it help if there were much larger nuclear powerplants in the desert that take in salt water via an aqueduct from the sea and send back fresh water to artificial lakes, depositing the waste into the desert? Salton sea might be a good enough spot in socal for example, where it is already toxic and salty.

The few times I've been to the Salton area, I was amazed at the agriculture in the middle of the desert, including things like citrus plants, despite smelling the stench of salton from there. There are various lakes that dry up all the time like big bear, what would it take to keep such basins capable of sustaining fresh watter topped up with desalinated fresh water, instead of directly consuming it? In other words, making desalination an upstream element, with the goal of resisting drought overall, not just immediate fresh water supply.

I've ever wondered about places like death valley, if the elevation there is so low, is it easier to build geothermal plants that could desalinate at a greater rate there?

And since I'm asking dumb questions already, if an aqueduct to LA is possible at a 4 hour driving distance, then I know it would be costly, but is it that impractical to build an aqueduct from the great lakes, which have no shortage of fresh water, and evaporation loss could easily be recouped by the sheer volume of available fresh water supply.

The Owens River source for LA is so good because it’s basically a continuous gradual decline from the source to the city, requiring no pumps.

Pumping is very energy intensive. At around 2000-3000 ft the energy needed to pump fresh water starts to equal the energy needed to desalinate the same amount of salt water.

Even if it’s just going up then back down again like the Tehachapi Mountains only like 1/3rd of the energy can be reclaimed.