What Comes Out of the Tap

Americans are fortunate in their water, and the good fortune is easy to take for granted. Turn a handle almost anywhere in the country and clean water arrives, a small daily miracle that much of the world does not enjoy. Yet the confidence the tap inspires can run a little too deep, because safe by law and known in detail are not the same thing, and the distance between them is worth a homeowner's attention.

Public water systems in the United States are regulated under the Safe Drinking Water Act, and the utilities that serve most households are required to test their water and to report the results each year in a document sometimes called a consumer confidence report. That report, free for the asking and often posted online, is the natural first stop for anyone curious about their supply. It describes the water as it leaves the treatment plant and travels through the public mains that run beneath the street.

The difficulty is that the water leaving the plant is not always the water arriving at the glass. Between the main in the street and the faucet in the kitchen lies the household's own plumbing, which the utility does not control and the annual report does not describe. Older homes may carry water through pipes joined with lead solder, common before it was restricted in the mid-1980s, or through an aging service line. What happens in that last private stretch is the homeowner's responsibility alone.

A great many American households draw their water not from a utility at all but from a private well, and here the gap widens into open country. Private wells generally fall outside the federal testing rules, which means no one is examining the water but the owner. A well answers to its own depth, to the geology around it, to nearby farming or septic systems, and to seasons of heavy rain, and none of that announces itself in the taste of a glass on the counter.

There are sensible occasions to look closer. Water that stains fixtures, carries an odor, tastes of metal, or leaves a chalky scale behind is asking to be understood. So is a household with an infant or an expectant mother, an old home of uncertain plumbing, or a private well that has never once been checked. The inquiry begins with the utility's report and, where the situation warrants, proceeds to a certified laboratory that can test a sample for specific concerns rather than vague ones.

A page of laboratory results, though, is written in a language of contaminants and thresholds that few homeowners read fluently, and a figure on a page rarely tells a family what, if anything, they ought to do about it. That is why a growing number of households consult a home water treatment company to interpret the results and, where the findings warrant it, to correct them. Sound counsel at this stage is chiefly a matter of proportion: knowing which readings are cosmetic nuisances and which deserve genuine action.

Where treatment is called for, the remedy should fit the problem rather than the fashion. A simple carbon filter at the tap addresses taste and certain common concerns; a softener answers the hardness that scales pipes and shortens the life of appliances; other troubles call for other tools entirely. The wrong device solves nothing while lending a false sense of safety, which is worse than no device at all. The aim throughout is to match the fix precisely to the finding.

The purpose here is not alarm. American tap water remains, on the whole, among the safest and cheapest in the world, and most households will find little to trouble them. The purpose is stewardship: to treat the water supply as one treats any part of a home worth keeping, with occasional attention rather than blind trust. A household that knows what comes out of its own tap has traded a vague unease for a plain fact, which is very nearly always the better bargain.