Tvov wrote:
"Bottled" water was at some point "non-potable" water - it just has been filtered, treated, and tested. Same with your "city water".
The vast majority of rural households pump water from wells and use it untreated (maybe a water softener but that's not an issue of potability)... but well water is typically free from organic contamination.
City system well water could be used in the same way but liability and PR push them to use more extensive treatment. When you hear about "boil water advisories" it's pretty much never due to issues at the wells. It's related to issues where the water can pick up stuff after the well head while it's passing thru the system.