That seems to be a problem related to construction rather than operation. It should be safe to assume they'll be watching out for that sort of thing in the future. I hope.
The contamination was in the wastewater treatment system, not the drinking water system.
I know from a hospital business career, bacteria is present every where and even semi closed systems like HVAC can serve as incubators for bacteria. Not an insurmountable problem but a useful problem for those against data centers .