I swear people will start to throw legality and lawsuits around over anything these days to the point of it being frivolous.
While clean drinking water availability might be important and legally required by some law (etc) out there, I'm not sure getting worked up over public water fountains in school being shut off is anything worth talking about, never mind demanding free bottled water or school closure. Their budgets are thin enough as they are.
My school(s) didn't even have water fountains or alternative provision: we just filled up a cheap PET with tap water at home + took it in with us. Heck, I don't even have "safe" drinking water in my own home: I buy bottled water. Why? Because the pipes are made of lead and have levels far above the legal limit. I might not be able to afford replacing them, and the council can't do it, but I'm quite sure no legal avenues exist for me to have the entire flat stripped and redone for the plumbing :_;