We've got a pretty good-sized data center at work, and it's a closed-loop system. I could see them needing lots of water if they're using an evaporative cooling system, but I don't think they'd risk having the systems taken down by a broken water main.
I go into a lot of data centers. Most large ones will use cold water sources with some kind of backup system. The backup is usually only rated for a short time and does not have the capacity to replace the chilled water.
The article claims they use a estimated 1.7 millions gallons/day. They may have some onsite storage to outlast a broken water main, but not a shut off.
An extreme water ph adjustment will render the whole system useless in a month.