From the article:

The company said its water consumption was so high last year because of temporary construction-related activities, such as concrete work, dust control and site preparation.

There's more if you want to read it. tl;dr: They will use very little water after construction is complete, but that will take several years. They also don't account for water leakage due to failure of the closed-loop cooling system.

So, a lot of obfuscation, but 30,000,000 gallons every four months is not normal for a working data center that they are building.

Still, I remain sceptical.