FYI - Bottled water isn't necessarily safe either...

[turil.livejournal.com]

Bottled water isn't tested for bacteria. (An NRDC study found that about 1/3 of bottled water tested was found to be contaminated by things including bacteria, arsenic, and synthetic organic compounds.)

So your best bet, for drinking water in Somerville right now, is to get FILTERED water, with a water filter that has a micron rating of 1.0 or less.

Or boil your tap water, like the MWRA recommends, until further notice.

Or drink your rainwater you've collected in your rain barrel (and you can filter or boil it if you like, as well). :-)