@mfuhrmann There is a map with #Drinking_water points, sometimes called "drinking fountains": mapcomplete.org/drinking_water (the drinking water layer is also included in plenty of other maps, such as https://mapcomplete.org/cyclofix and https://mapcomplete.org/nature)

However, there is no map (yet) for decorative #fountains as described here: https://wiki.openstreetmap.org/wiki/Tag:amenity%3Dfountain

If you are feeling up to a challenge, you can give https://mapcomplete.org/studio a try

Cyclofix - a map for cyclists

A map for cyclists to find the appropriate infrastructure for their needs, such as bicycle pumps, drinking water, bicycle shops, repair stations or parkings

Study finds hundreds of contaminants in U.S. drinking water

YouTube
Chlorine plus UV light can detoxify water affected by harmful algae blooms

Treatment plants use a combination of tools to keep toxins and contaminants out of drinking water. Researchers with the University of Cincinnati have examined two such tools in addressing a toxin produced by harmful algae blooms, which are becoming increasingly common in waters around the world.

Phys.org
Chlorine plus UV light can detoxify water affected by harmful algae blooms

Treatment plants use a combination of tools to keep toxins and contaminants out of drinking water. Researchers with the University of Cincinnati have examined two such tools in addressing a toxin produced by harmful algae blooms, which are becoming increasingly common in waters around the world.

Phys.org
Predatory bacteria provide hope for chlorine-free drinking water

In a unique study carried out in drinking water pipes in Sweden, researchers from Lund University and the local water company tested what would happen if chlorine was omitted from drinking water. The result? An increase in bacteria, of course, but after a while something surprising happened: a harmless predatory bacteria grew in numbers and ate most of the other bacteria. The study suggests that chlorine is not always needed if the filtration is efficient—and that predatory bacteria could perhaps be used to purify water in the future.

Phys.org
Biden's Woke Water Will Deny Americans 'Forever Chemicals' Their Bodies Crave

But it will cost money to remove them from drinking water. Is better health worth money?

Wonkette