The Pittsburgh Post-Gazette looks at the bottled water scam (to quote from the title of the article). A nugget:
In fact, tap water may actually be cleaner. Last month, researchers found that some bottled water contains more bacteria than tap water. More than 70 percent of the popular brands tested in this new study failed to meet bacterial standards set by the United States Pharmacopeia, a nongovernment agency that sets safety standards for medications and health-care products, according to the Montreal Gazette.
In comparison, tap water is usually so pure, bottled water companies can simply bottle it and sell it to you. For example, Coca Cola-owned Dasani bottled water often comes from local water utilities. Visit its website and you can follow the eight-step Dasani treatment process, but never once read which contaminants are so terrifying that the company needs to disinfect the water all over again. If it’s taste you’re after, you can spend up to $5.50 a gallon on the bottled stuff, or as low as $0.15 per gallon for tap water with a home filter.