Taste Tests

The Southern Nevada Water Authority (SNWA) has trained some of its staff to evaluate the aroma and taste of drinking water. These employee volunteers serve on a water Flavor Profile Panel.

This team of trained water tasters may not have as much fun as wine tasters, but they are helping ensure the high quality of Southern Nevada's drinking water. Since June 1999, these employees meet weekly to evaluate drinking water in the Las Vegas Valley from a variety of sources.

Findings

The panel members have discovered that the dominating aroma in our water is from chlorine. Typically, panelists can only recognize the chlorine aroma in the finished water, with occasional references to a "dusty" or "musty" aroma, which is associated with the water's high mineral content. The panelists have described two other flavors attributable to the chlorine—"bitter" and "dry mouth feel." Our water tasters also described a chalky flavor and a saline mouth feel.

Other findings

The panelists have tasted samples with particular water quality problems. They were able to pinpoint the water quality concern based on the flavor of the water. This demonstrates what a powerful tool flavor profile analysis is in troubleshooting and identifying trace levels of some contaminants.

The flavor panels also have detected other problems in blind tests, such as an algal bloom in a reservoir (described as "green" and "chlorophyll") and fresh PVC pipe installations (described as "plastic" and "PVC glue"). Our tasters noted that cold water samples have less chlorine aroma than those at room temperature, and samples exposed to the atmosphere de-gas chlorine rapidly.