A water utility that supplies water to the same population year-round. It serves at least 25 people at their primary residences or at least 15 residences that are primary residences. Over 286 million Americans get their tap water from a community water system. Sources: Public Water Systems | Drinking Water | Healthy Water | CDC; Factoids: Drinking Water and Ground Water Statistics for 2007, March 2008 (epa.gov).