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by konschubert 892 days ago
If you desalinate 1 gallon of seawater, and then mix the brine with 10 gallons of seawater, the salt content of that seawater has increased ~10 percent.

If that’s still too much, use 20 gallons.

It’s a matter of spending energy on pumps, but it’s totally doable.

Also, the ocean salt content will not be increased by this, since the desalinated water will eventually make it back to the ocean.

2 comments

Yeah, but if you’re pulling in water and disposing it from a specific region, eventually the water that you’re pulling in is progressively saltier, and you’re compounding the saltiness of that area.

I’m sure that ocean currents will eventually equalize the salt, but if you’re continuously dumping salt into a specific area, it’s going to make that region of the ocean saltier.

You need pipes to spread it out. And I think you may be underestimating the scale and force of ocean currents. Every tide probably moves more water than California uses in a year.
I don't think the ocean is equally saline everywhere: https://salinity.oceansciences.org/maps-global.htm

On average it's pretty close, but you can definitely get impacts from increased local salinity: https://onlinelibrary.wiley.com/doi/full/10.1111/gcb.16859 (just random ecamples)

https://www.scientificamerican.com/article/slaking-the-world... (view in incognito)

Okay fair point.
Crucially but overlooked so far in these threads, is that the proposal does not have brine exiting on the California coast; it has it flowing into the Sea of Cortez.

That should be an obvious non-starter for anyone remotely familiar with the unique geography and ecology of the area.

But where are you getting that pure seawater from? If it's anywhere near the outlet, there's a scale at which the concentrated brine will affect the salinity of your inlet.
Yes, some pipes are needed. Beyond that, you rely on ocean currents. .