Attention! Here’s what you need to consider: How dangerous is tap water?

Mend says you should keep tap water cold in the refrigerator if you want to drink it later. In the dark, at low temperatures, bacteria multiply more slowly than at room temperature and daylight. Mend says it’s best to drink water from glass, clay or ceramic. Or from stainless steel bottles on the go. “They are opaque and the water stays colder longer.”

Mend says drinking warm water from a boiler is dangerous. Because you don’t know how long it’s been on the line and when the contents of the boiler were last used. This means you can only drink water from the tap on the coldest setting. For people who want hot water straight from the tap or need it for cooking, Mend recommends installing a Quooker. This system, which costs over 1,500 francs for private homes, allows 100-degree warm water to flow directly from the tap.

Filter systems connected directly to the tap and jug-shaped table water filters are rapidly increasing in Switzerland. If you do not maintain them properly and do not replace filter cartridges regularly, you run the risk of pathogens and microorganisms multiplying in them, giving the water a bad taste. Mend recommends filter systems made of stainless steel, which do not require plastic, electricity or chemical additives. In addition to filters made of activated carbon and zeolites, some stainless steel models are equipped with other elements such as a steel-silver mesh and thus retain 100% germs.

Mend says he doesn’t go on vacation without activated charcoal sticks. When dropped into a water bottle, the stick neutralizes unpleasant odors like chlorine and fortifies tap water with minerals. Japanese monks used this method to purify drinking water in the early 17th century. And to protect yourself from poisoning.

Mend says the water from drinking sodas appears lively in the mouth. “But that says nothing about its quality.” He compares his homemade “Blöterliwasser” to a repainted old car. “It looks better, but it’s still old.” At altitudes above 1500 metres, there is no need for truly fresh spring water such as from the tap. “Alive even without additional enrichment.”