Tap water comes in many flavors. In fact, it can be so specific to each locality that some people consider it the secret ingredient in New York bagels and pizza. But unpalatable drinking water can prompt people to scramble for filters, trying to rid their water of the flavor of pennies, dirt or bleach.
Moreover, people may worry that funny-tasting tap water may carry dangerous substances or pathogens. There is evidence that tap water has been the likely source of some disease outbreaks, including Legionnaires’ disease and gastrointestinal illnesses, although, in many outbreaks, researchers can’t be sure of the culprit.