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by ashdksnndck 11 days ago
If you use fat pipes that go a decent distance from shore, diluting your brine with ocean water, you’ll have a negligible impact on the ocean. The problem is if you dump lots of brine in shallow waters. Old designs did have that flaw, but it’s not that difficult to design around this constraint now that we know about it.

IMO this is an issue where NIMBYs are using environmental concerns as a smokescreen to block new desal plants from ruining the vibe at their beachfront property. Rhymes with the opposition against offshore wind farms.

4 comments

The city of Corpus Christi, TX is currently considering options for desalination plants—all of which pump their brine into the shallow water inside the bay or the ship channel.
Sounds on brand for Texas.
> The problem is if you dump lots of brine in shallow waters. Old designs did have that flaw, but it’s not that difficult to design around this constraint now that we know about it.

I think that problem was known (and discarded as not important) when the first serious water desalination plants were built.

I can probably be convinced pretty easily with some evidence of that, but you’ll never convince the contingent who is convinced it’ll kill sea life at any concentration or location, so, being able to shut them up by saying “we have no wastewater, we load rail cars with crunchy salt and use it for stuff” still has value.
I wish we could reimagine carbon credits to that degree of stringency. You offset a kg of carbon emissions? Let's see that kg.
The goalposts will just shift to attack that excess salt instead. It’s like all of the FUD about datacenter water usage while people shove almonds in their mouths.
In Germany, it's the water usage of a Tesla plant vs. the neighboring asparagus farm.
Yeah. Worrying about salt in the sea is like worrying about oxygen in the air. Can too much oxygen in the air sometimes be a problem? Yeah, in some corner cases. Is it a major problem that we can't solve? Not at all.
Isn't it more akin in this case to worrying about too much carbon dioxide in the air?
Why is it akin to that? Doesn't the salt come from the sea in the first place?
A more apt comparison than you realize.

Most of the carbon we spew into the atmosphere came from the air. Ancient plants took it in via respiration.

That still doesn't make it a good comparison. The salt emitted by desalination plants is already in the sea now, it's not salt that went somewhere else.
And the water we take out eventually goes back.
That makes sense to me. At the same time I know the mediterranean sea is heating up more because it cannot move heat out quick enough. I dont know of any mediterranean air, so I believe more closed water zones would behave different than, lets say, the atlantic ocean.