In the US, yes - public tap water is among the most regulated products you consume: the EPA sets legally enforceable limits on dozens of contaminants, and utilities must test, treat, and report to you annually.
The CDC is plain: water utilities are required to meet safety standards for public tap water. The real caveats are local: pre-1986 plumbing can add lead, private wells are unregulated and need annual testing, and boil-water advisories override everything when issued. Pymander's escalation routing is built and tested specifically for this class of decision; see the safety architecture working paper .
What to do
Common questions
Is tap water safe to drink?
In the US, yes - public tap water is among the most regulated products you consume. The Safe Drinking Water Act gives the EPA legally enforceable standards - Maximum Contaminant Levels - limiting dozens of contaminants in public water systems, and utilities are required to test, treat, and report, including mailing you an annual Consumer Confidence Report. The CDC's summary is plain: standards exist to keep you from getting sick from public tap water, and water utilities are required to meet them. The honest caveats are local, not national: old building plumbing can add lead after the treatment plant (a certified filter or a flush-and-test handles it), private wells are unregulated and need annual owner testing, and boil-water advisories override everything when issued. If you want certainty about your own tap: read your utility's annual water quality report, test if your home predates 1986 plumbing, and filter with an NSF-certified product matched to the contaminant you actually found. For most people, the safest and cheapest water in the house is already running from the tap.