passes through an industrial treatment plant by the mouth of the Canyon. This results in a very sterile tasting water that some prefer. Pleasant Grove water is pulled from natural springs and underground wells so it doesn't need to be treated. Since it's untreated from the ground it may pick up some after-taste there (although it's perfectly safe to drink). This is more likely if the well you're drinking from is lower in the valley, as water quality diminishes the further you get from the mountains.

Incidentally, all Provo City water is pulled from natural springs high on the mountain and is, in my opinion, some of the best municipal drinking water in the country.