The fact that so much has improved for Swiss water is mainly due to the sewage treatment plants. Today, 97 percent of households are connected to a sewage treatment plant. The rest lives in areas so remote that it makes no sense to connect them.
Blue Lake, New Zealand. The Blue Lake is the clearest lake in the world. New Zealand is well-known for its natural beauty, with mountainous terrains surrounding crystal clear lakes whenever you hop out of the city.
Lake Annecy, FranceLocated in the Haute-Savoie department, which borders Italy and Switzerland, Lake Annecy is a pristine body of water that's often called the cleanest lake in Europe, thanks to strict environmental regulations set in place in the 1960s.
Best lakes in Switzerland: BlauseeNestled in the Kandertal mountains, Blausee translates to 'Blue Lake', and its stunning colour is why so many people flock to this small body of water. You can't swim in this lake, but you can take a boat ride on its crystal-clear waters.