Bottled water is often see as the "pure" choice for drinking water. These beverage companies would have you think that tap water is bad for you: contaminated with pesticides, bacteria, etc. But how true is this? All too often we take these scare tactics at face value. Just how clean is the water we drink?
Generally (in the U.S. anyway), tap water is perfectly safe. While testing may yield trace amount of various chemicals, they are generally usually at such low concentrations that they pose no serious threat to most healthy Americans.
To find out specifics regarding your area's drinking water, visit the Environmental Protection Agency's (EPA) website. They supply annual public reports regarding local drinking water. Though it's worth noting that not every region has a corresponding report.
A much more specific source, the Environmental Working Group (EWG) produces similar findings and allows you to navigate through the specific chemicals that have been detected in your drinking water. Most of the time, you'll see that a small amount of contaminants are well within the legal limits and pose no threat, unless you have a specific sensitivity.
The biggest concern with buying bottled water (aside from filling landfills with plastic) is that is isn't regulated as heavily as tap water. The FDA doesn't monitor water as closely as the EPA. You can easily find out online what you're drinking if you drink from the tap, but it's much more difficult when you buy a private label. Almost 200 different brands of bottled water exist, and only a small fraction of those (2 companies in 2009) report their breakdown. What you think is crystal clear glacier water might be filled with‚ anyone's guess.
Some states such as California have required private companies to disclose some of this information by placing contact numbers on the label for consumers to request quality reports. To view how the EWG scored these companies, you can visit http://www.ewg.org/research/ewg-bottled-water-scorecard-2011. Most received failing grades and/or scored a "C"or less. Note that this rating system is for transparency (i.e. noting the source of the water and details of how it is purified), not necessarily the purity or quality of the water.
While we're not suggesting that bottled water is unsafe, it is worth giving a little extra thought into your daily decisions to drink from the tap, filter your own, or buy bottled. What's really important is that your are drinking enough water. What has been your experience? How does the tap water score in your city?