While chlorine is a common disinfectant, too much residual chlorine can be the difference between 'good' water and 'bad' water.



For hundreds of years, the conventional wisdom has been to treat water centrally and pipe it to its users. This brings up several challenges.

In many areas of the country, a significant challenge exists in dealing with the definition of “What is acceptable water quality?” Standards often provide for minimum acceptable limits, recognizing that making water “perfect” is an impossibly large expense.

Even in many developed areas, where centralized treatment is in place, there are localized water quality issues that are objectionable, but costly to address from a centralized approach to treating water. Take, for example, the recently tightened limits of 10 parts per billion of arsenic. In some parts of the country, arsenic levels are actually quite higher.

As municipal water authorities struggle with the ever-increasing burden placed on their facilities, the demand for more and more water to support a growing and ever more industrializing population also continues, which leads to the next challenge ...

Recent trends in water treatment technologies have given rise to the notion of point-of-entry (POE) and point-of-use (POU) treatment as a means of minimizing the huge infrastructure costs associated with centralized treatment. These decentralized treatment alternatives give hope to the many millions of people in smaller areas, which simply cannot afford the expense of upgrading centralized treatment and piping infrastructure.

Over time, decentralized treatment technologies will gain in popularity simply because there is no reasonable alternative.

Centrally treated water, sent to its users via pipes, is also subject to re-contamination in transit, unless it's protected by a residual level of disinfectant. Unprotected standing water and water transported in decaying pipes in many areas can be recontaminated very easily.

Generally speaking, chlorine is the disinfecting agent of choice in municipal treatment plants. It is inexpensive and in the proper doses can easily deal with pathogenic organisms, such as viruses and bacteria. A small residual of chlorine also can be left in product water to protect it in transit through the piping infrastructure.

Consequently, oftentimes the municipal definition of “acceptable” as it relates to residual levels of chlorine or post-treatment levels of compounds such as sulfur is closer to “nonharmful” than “pleasant tasting.”

This cost-driven threshold of acceptability also has helped define and grow the mushrooming market for POE and POU treatment devices, which are placed at the end of municipally supplied water systems.

Research conducted several years ago indicated that more than 40 percent of the United States' population is deeply concerned about their water supplies, to the extent that they had taken some active steps to improve it. These “water-worriers” had purchased a wide variety of treatment alternatives.

However, that same research indicated that most of their perceived need was based on the elimination of chlorine taste and odors, such as sulfur.

A variety of products are available to effectively remove chlorine taste and odor from residential and commercial drinking water dispensers. These mostly in-line or faucet-mounted cartridge devices usually are comprised of a carbon block or granulated carbon filter, and can be readily replaced when they reach their prescribed volume limits.

On municipally processed water, these filters are a good choice to address the chlorine taste and odor issue, which amounts to the primary difference between what the public considers “good” and “bad” water. And, as an added bonus, some of these carbon filters remove plenty of other compounds.

Meanwhile, the same municipal water supplies drinking fountains and plumbed-in water coolers in public or commercial facilities. Today, there's simply no reason why a contractor can't provide great tasting water from a public fountain just as well as they do so in a customer's home.