Drinking Water: To Tap or Not to Tap

by Bill Chameides | December 9th, 2009
posted by Erica Rowell (Editor)

Permalink | 2 comments

Peatland fires — which have produced massive plumes of haze and air pollution that can spread over thousands of miles — have become a significant source of global warming pollution. (Indonesia/Sumatra, 2006, NASA)

The accepted green wisdom is to drink from the tap not bottles. Maybe, maybe not.

We all know to shun those plastic bottles of water at the supermarket and convenience store. Right? That’s been my advice right here on TheGreenGrok (see my video on sustainable shopping tips — about two minutes in).

The embodied carbon emissions in the water and bottle are huge. And why in the world would someone buy water in a bottle that’s been shipped from some other place when you can get all the water you want, anytime you want, just by turning on your sink’s tap?

The answer: check out yesterday’s lead story in the New York Times.

Widespread Pollution Out of the Tap

It’s a shocker. Charles Duhigg reports that

“more than 20 percent of the nation’s water treatment systems have violated key provisions of the Safe Drinking Water Act over the last five years … [and] since 2004, the water provided to more than 49 million people has contained illegal concentrations of chemicals like arsenic or radioactive substances like uranium, as well as dangerous bacteria often found in sewage.”

Yikes! What’s a public-water system drinker to do? Fall off the wagon and start buying bottled water? Hardly.

Get the Facts About Your Water Supply First

Before you panic and buy a year’s supply of Aquafina (no placement advertisement, I promise), find out if the water in your tap routinely violates the Safe Drinking Water Act, and if so, why?

Every time a public water system has a violation of any kind, it is reported to the Environmental Protection Agency, which publishes all that information at its Safe Drinking Water Information System site. So, in just a few short clicks, you can find a record of all of your water system’s violations.

For example, I was able to find out that the water in Durham, North Carolina, where I live, violated the standard for haloacetic acids (byproducts of chlorination) between January and March 2009. But that is the only “health-based violation” (i.e., a violation where a pollutant concentration was measured to exceed the standard) that appears.

There were plenty of “monitoring violations” where the system failed to take some percentage of the required samples. However, these are procedural and not evidence of an actual health violation.

But what about that haloacetic acid in my tap water? A major problem? I don’t think so.

Do a Little Water Treatment of Your Own

Haloacetic acids may be in my tap water, but not necessarily in my glass. How? It’s the old pollutant-disappearing magic act using … a water filter. That’s right; many of the filtration systems on the shelf at your hardware store or supermarket can provide a good deal of protection from the pollutants mentioned in the Duhigg piece, including haloacetic acids.

However, it’s important to know that not all water filters are the same.

  • Some filters are designed to remove a certain percentage of targeted contaminants (such as bacteria, lead, arsenic, organics) while others aim to remove more.
  • Some do not typically remove contaminants like radionuclides (e.g., radioactive uranium).
  • Some filters introduce their own health drawbacks — for instance by removing minerals your body needs from the water.

The bottom line: just any old water filter does not guarantee safe water. You must do some research.

  • First find out what kinds of pollutants are getting through your public water system’s treatment plant.
  • Then make sure you get a filter that can remove them.

Okay, you say, “Not good enough. I want to be 100 percent sure, so I’m opting for bottled water.” That may make you feel 100 percent sure, but you’d be wrong.

What’s in Your Bottled Water? You Just Don’t Know.

Just because water is in a bottle you paid good money for doesn’t mean it’s safe, even if the label says it comes from some pristine stream two miles shy of Shangri-La.

Unlike public drinking-water systems that are carefully regulated by EPA under the Safe Drinking Water Act, water bottlers are not required to treat their water, or monitor it regularly for contaminants, or report findings of contamination.

In fact, some studies have found that the quality of bottled water is often no better and is sometimes worse than what’s in the tap. In fact, often bottled water is simply tap water from some other location. (There’s also the potential problem of bisphenol-A or BPA leaching from the plastic into the water. See this post about BPA.)

Regrettably, even in the United States — the place we like to call the richest country in the world — the drinking options are not great.

For now, I’m going to stick with tap water plus a good filter that I change regularly (if you don’t swap it out for a new one, the old one stops filtering and you might as well not have one). That may or may not make sense for you.

In the meantime, I think we can all agree that better enforcement of the Safe Drinking Water Act would be nice. According to Duhigg’s article, Lisa Jackson and the folks at EPA are on the case.

Further Information

1. What to Look for in Water Filters – There’s a lot of good information online. Here are some basics to get you started.

Of the many different water filters on the market, there are generally three types:

  • whole-house filters that treat the water as it goes into your home,
  • point-of-discharge filters that treat the water at the tap, and
  • pitchers.

The key ingredient in most filters responsible for removing a good deal of the most common contaminants is activated carbon.

The size of the filter’s holes is also important. Micron ratings range from 50 to 0.5, with the smallest being the most effective.

Be sure to get a filter that has been certified by the National Science Foundation to address health-related contaminants (standard 53), and read the material closely to see that the filter you choose removes your contaminants of concern.

Lastly, remember to change the filter regularly as they become less effective with age. For example, one study found that the Brita Ultra filter’s efficacy in removing haloacetic acids dropped from almost 95 percent when it was newly installed to 50 percent when more than half of the filtering capacity was used.

2. What Else Can You Do?

Take a look at EPA’s recommended actions. In brief, EPA first suggests getting a copy of your public water system’s annual report to see if there are any contaminants of concern.

If there are (or if you have concerns about lead in your home’s plumbing), the site has links to certified water-testing laboratories in each state that can provide an independent analysis of the water that actually comes out of your tap.


Correction: On 12/2/2010 this post was amended to add the words “of chemicals” to the direct quotation from the New York Times.

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  1. Abram
    Dec 11, 2009

    You should definitely get counter top reverse osmosis water filter systems i got my filter from here.. water tastes much better with it…

    • Plower
      Dec 14, 2009

      Unfortunately, I believe in most communities, it is necessary to filter your water. Water treatment is to kill pathogens, and these chemicals are not really good for your body.

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