Earlier quoted context omitted.
Yes, it was well water. According to the article: > Amoebas may be found in fresh-water sources around Puget Sound such as wells, but aren’t present in city-treated water, according to Liz Coleman, a spokeswoman for the Environmental Public Health division of the state’s Department of Health.
Right. I wasn't sure if Coleman was saying "it couldn't have happened from her tap water, because it's treated" or if the implication was that the victim had a well. I like your interpretation- the latter.
The main difference between well water and non-well water is that well water is not centrally treated by the water department. There will be filters and stuff, but it is not treated the same way.