Could fluoride in drinking water prevent tooth decay?

Absolutely !: Together with eating healthy and proper oral hygiene, as well as regular visits to your dentist. Every little bit helps !

Public fluoridation: It can't necessarily guarantee it, but it could certainly make your teeth stronger and less likely to develop caries (tooth decay). This along with proper tooth brushing, flossing and a diet that does not promote tooth decay will all aid in preventing tooth decay and a healthy mouth.

Of course: "Since 1950, the ADA has unreservedly endorsed the fluoridation of community water supplies as safe, effective, and necessary in preventing tooth decay."

Yes: Plenty of studies and literature on this. One of the most positive things to happen in the last 60 years for the prevention of tooth decay.