I use city tap water for all my beers and everything seems ok except for the weird unexplained twitches and seizures I've started having since I started brewing. I'm just kidding...I can't remember what book it was in (maybe Papazian's?) that said a general rule is if your water is OK to drink it'll make beer just fine. That said, I wouldn't worry about boiling tap water, just brew away.
Great Outdoors Brewery:
You can't drink all day unless you start in the morning!
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