Since 2015, several data centers have been submerged underwater in both the Pacific Ocean and Atlantic Ocean. The first underwater data center was deployed by Microsoft into the Pacific Ocean, off the coast of California, through an experiment called Project Natick, with Phase 1 being a vessel carrying 1 rack, containing 24 servers.
Some datacentres are already run under the water, this shouldn't be too different.
Fresh water not salt water silly
no very much salt water I'm afraid.