Best tasting tap water I have ever had is in the city of Sonoma in California. I really don't know how to describe it. Other places I have tried- Japan, Spain, lots of CA, NYC, MA, NC... that's about it.
I drink tap water all the time.
Also, as I understand it the environmental impact of discarding empty bottles isn't as significant as the energy spent transporting bottles of water. It is much more efficient to carry water through pipes. Something I heard somewhere, as of now I am unable to back it up with anything reputable.
give me a few minutes though and I will put it on wikipedia...