https://en.wikipedia.org/wiki/Desalination#Outflow https://en.wikipedia.org/wiki/Desalination#Outflow . In short, it needs treatment due to contaminants, and di

https://en.wikipedia.org/wiki/Desalination#Outflow https://en.wikipedia.org/wiki/Desalination#Outflow . In short, it needs treatment due to contaminants, and diffusion or dilution because high salt concentrations damage the ecosystem. These can be managed, but it's not "just" a matter of pumping the outflow directly back into the sea.