Question:
don't worry too much about small particle (pathologicalorganisms) filtration if you are using treated tap water. Filtrationis not foolproof in that regard. The key word is "boil". And I'd beequally concerned about the organic chemicals that get throughtreatment plants. Distillers and Reverse Osmosis units do a good jobon these, as well as on minerals, pathos, etc.If you look around, you should be able to get a small RO unit for notto much money. Especially if you can bypass some of the salespeople inbetween you and the manufacturer!As a retired water treatment plant operator, I always emphasize thatpeople should NOT drink their tap water without some sort of furthertreatment. I boil and filter (Britta at the moment) every drop I use.Pathogens can and do get through the water treatment plants. And themany post-chlorination products (ie: trihalomethanes, etc) are scareyitems produced BY our municipal methods of treatment.And, not to forget, we're training our taste buds to appreciate bettercoffee, right !

Answer: I respect your experience in the water treatment industry and I'm sure thatthe rest of us would be happier not knowing what goes on in a water plant,just as our enjoyment of restaurant meals is greater if we don't knowexactly what is going on in the kitchen (here's a starter - those "Employeesmust wash hands" signs don't work, especially if your employees can't readEnglish).

That being said, unless your immune system is compromised or you are in anarea where special warnings have been issued, most of us in the US and otherdeveloped countries do not need to be boiling our drinking water. Right nowwe are in a time of short energy supply and if the entire water supply wasboiled, this would be a huge waste of energy. There are much more energyefficient ways of sanitizing questionable water. Of course, water inside anespresso machine is effectively boiled already, so there is definitely noreason to be boiling it twice.

That being said, I'm also in favor of filtering drinking water. Where I'mat, the municipal supply is mostly river water and it sucks big time,especially in the summer.