Why does my tap water taste or smell bad?

An unusual taste or smell can come from the public supply, private well, household piping, a fixture or your water heater. Compare cold water at several taps and ask your water provider whether work or an advisory is affecting the area. A rotten-egg odor only from hot taps suggests a different starting point from an odor throughout the home. Do not assume that water is safe to drink because it looks clear, and do not use a generic filter as a substitute for identifying a contaminant. Follow official health guidance when a water advisory exists. Testing helps determine whether treatment or plumbing repair is appropriate.