As far as I know, Great Lake water is safe to drink, unless something has changed.
The county next to me supposedly has great water underground, which means the well water does not have to be treated. Same with the Hot Springs area in Arkansas and Saratoga Springs in NY. In fact, in Hot Springs Arkansas there is a large multi spigot fixture in town and people can walk up and fill potable drinking water whenever they want.
My bet is there are freshwater lakes and streams all over America that are safe to drink. I’m sure there must be places in other parts of the world. I would think Canada has a lot of freshwater, and of course Canada shares shoreline with the Great Lakes.