Is pipe water drinkable in cities of Bergamo and Milan in northern Italy?
Do the cities of Milan and Bergamo have drinkable tap water, or is the practice to buy bottled water?
Regardless of the city, what matters **most** is the quality of the building's tubes. So it basically depends on which building are you on.
@Lohoris - Based on the answer below, and your comment, can I assume that people usually buy water and do not drink it uncooked from the tap? My gut tells me the answers are going in that direction but no one wants to state it bluntly. I.e. it is drinkable, but this is the common practice.
No, usually people drink tap water if the tubes of their building are good, and buy bottled water if they aren't. Sometimes they filter tap water with a purifier, as shown in the answer, usually when it is not so bad to be unsalvagable, but not so good to drink it as it is.
Tap water is always drinkable in Italy, especially in the cities (of course, it may be a little bit different if you are talking about a cottage in the middle of nowhere).
The real question is how good is that. For instance, in Rome the water has a very strong percentage of limestone and it taste doesn't very good. For this reason, several people tends to buy a water purifier or a simple purifier container like the following one.
In smaller cities, like Bergamo, pipe water is definitely better than bigger cities. Specifically, in Bergamo the pipe water seems to be one of the best in Italy.
Talking about Milano, and big cities in general, it depends on where you live (how far from the main water collector, the quality of the pipes, etc). My suggestion is to either try, ask the neighbours or use a water quality test to check the quality of the water in the apartment.
In any case, it's potable. So you can drink it, or use it for a tea or coffee. It may not taste extremely well or the amount of mineral salt may be greater than what you would expect.
Let me rephrase. Is it usual for people who can afford bottled water everyday to drink tap water in cities in question? (Water, in my mind, which needs to be cooked or which tastes strongly of limestone, is not drinkable. It can be consumed, but I'm talking of everyday consumation, which is obviously not something somebody would do were they offended by the taste.)
No, in general you may want to buy bottled water. Water is very cheap in Italy, compared with other countries.
Italians buy A LOT of bottled water. I believe it's the biggest market in the world. And bottled water is really cheap: 1 litre bottles sell for as low as 10-20 cents in supermarkets. (also San Pellegrino is very cheap, as it's considered just water and not a fancy soft drink)