YOU get a bill. Society pays for public drinking fountains, homeless shelters, section 8 housing, etc... where water is provided for the less fortunate at a scaled societal contribution (or free).
Flint MI is an absolute crisis and the government has stepped in, the state of Michigan sued the city, and there have been over a dozen criminal indictments. Multiple governments have stepped in to repair the obligation of clean drinking water, and to punish those who failed the citizens.
You got it backwards. There is no obligation to provide drinking water. In fact most places where the city puts it in they force people to use the provided water and NOT put in wells. Then they send a bill.
Also, I know folks on well water that live outside of the city, society does not provide their drinking water.
Also, There is Flint MI.