Taste and Odor

Chlorine

Water suppliers are required to keep a small amount of chlorine in the water supply for disinfection purposes. The amount of chlorine is typically a few parts per million or less, which is equivalent to a few pennies in $10,000. The chlorine might be pure, referred to as "free chlorine" or it might be a combined form of chlorine referred to as chloramine. Chloramine is a longer-lasting disinfectant than free chlorine and often people are less sensitive to its taste and odor.

Algae

Some types of algae produce non-toxic chemicals that people can taste and smell in drinking water at levels as low as a few parts per trillion, which is equivalent to a few pennies in $10 billion. During hot, dry weather, chemical compounds call Geosmin and Methylisoborneol (MIB) are produced by some algae. These can impart earthy, musty odors to water. Although traces of these chemicals can be found in drinking water, you can be assured that the water meets all standards of the Federal Safe Drinking Water Act.

Road Salt

During winter months, the salt sprayed on the roads can make their way into our waterways and eventually surface water treatment plants. Water treatment plants are unable to remove road salt. During periods of repeated road salt applications, there is potential that it will impact the taste of your drinking water. These events are typically short lived

Minerals and Sulfurous Compounds

Tastes and odors are generally less common in groundwater sources. However, in some regions sulfurous odors are common in well water. Stale odors and metallic tastes are also sometimes reported in groundwater. These odors are usually due to a combination of local mineral deposits and natural underground chemical and biological processes.

Our tongues sense bitter, sweet, sour and salty tastes. Olfactory nerves located above the roof of the mouth sense odors. Together, tastes and odors are perceived as flavors. However, people sense flavors differently. For example, some people may be sensitive to flavors that others can't distinguish at all. That is why people living within a household or neighborhood might notice water tastes or smells that others do not.

It is not uncommon to perceive an odor from another source as being from your drinking water. For example, if there is something causing an odor in your drain, you could perceive it as coming from the tap. This is particularly true first thing in the morning when a drain has been stagnant.

Aqua continuously monitors and samples the water in its reservoirs, streams, treatment plants, groundwater wells, businesses, and homes. Samples are analyzed for bacteria, chlorine, pH, algae and many other chemical constituents every day. Water treatment operators test the water at treatment plants for tastes and odors. These operators are often the first to identify a taste or odor and can usually respond with treatment changes before the water gets through the treatment process.

Aqua's research laboratory conducts "flavor profiles" to taste and smell water samples. These flavor profiles employ a formal test procedure under controlled conditions to evaluate samples. Because individual sensitivity varies and people detect tastes and odors differently, it's important to use more than one tester.

The lab uses state-of-the-art instruments to test water samples for trace amounts of odor-causing compounds like Geosmin and Methylisoborneol (MIB). These tests can accurately measure levels of some chemicals to less than one part per trillion. Because the tests require specialized instrumentation, few laboratories have the capability to analyze these types of samples. Treated drinking water tests for bacteria and chemical contaminants are more reliable indicators of safe water than our senses of taste and odor.

To reduce the taste and odor of chlorine, Aqua uses chloramine in many of its systems. Scientists carefully monitor the amount of chlorine added to the water supply to control chlorinous odors and maintain disinfection for safety.

Chlorine can also eliminate some tastes and odors caused by algae, but Geosmin and Methylisoborneol (MIB) must be removed through more specialized treatment. The specialized treatment approach used by Aqua varies by location. This treatment will reduce the impact of the algae on taste and odor, but may not always remove it completely.

Aqua works to prevent algae blooms by controlling sediment and nutrients in our reservoirs through watershed protection activities, the weeding of aquatic plants and reservoir maintenance, including dredging projects.

Tastes and odors are less noticeable in cold water and more apparent in water that is kept at room temperature or heated. Chilling a pitcher of water in the refrigerator overnight will usually make chlorine disappear and eliminate a chlorinous taste and odor. Water that lacks chlorine should remain refrigerated like any other opened beverage, to reduce the chances of bacteria growth.

Aqua would like to know when and where customers are detecting tastes and odors. Please call 877.987.2782 if you notice a change in the way your water tastes or smells. We track these calls closely so we can address problems that might occur and improve the quality of the water delivered to your home.