10 or so years ago I read an article that thanks to environmental efforts we now have rivers and lakes that haven't been this clean since at least pre-industria

10 or so years ago I read an article that thanks to environmental efforts we now have rivers and lakes that haven't been this clean since at least pre-industrial era. We went from the Great Stink https://en.wikipedia.org/wiki/Great_Stink https://en.wikipedia.org/wiki/Great_Stink to having beaches and swimming competitions inside big cities