How many times has the fresh water supply been drank by other people?

The concept of "fresh water supply" being "drank" by people is complex because water is part of a continuous cycle. Water that we drink has likely been consumed multiple times over centuries, as it evaporates, condenses, and falls as precipitation. Estimates suggest that individual water molecules may have been part of many different drinking experiences throughout history. However, quantifying this precisely is impossible due to the nature of the water cycle.