Equally interesting is their impact on the electrical power grid.

This piece (at a website I know nothing about) claims AWS next generation data centers will use "closed loop" water systems: https://www.aboutamazon.com/news/aws/aws-liquid-cooling-data...

It seem that problem is not the use of water itself, but the fact that datacenters buy drinking-quality water under the same conditions and from the same source as regular citizens. Sure enough they are not doing it because there are no other ways, but because this way is cheaper.

There appears to be quite easy way to fix the situation by making it more expensive than using sea water or investing in closed loop solutions.