This is difficult to authoritatively respond to without knowing the exact source of what you're talking about, but I suspect you'll find that those tests are on

This is difficult to authoritatively respond to without knowing the exact source of what you're talking about, but I suspect you'll find that those tests are on the water from the pipes, not in the reservoir, and that there are in fact processes the water goes through while being transferred from one to the other. They have, like, videos of it on their website, they're very proud.