Drinking Water Nitrification Surveillance Program

Nitrification is not addressed by the current Safe Drinking Water Act regulations, but it can significantly deteriorate water quality in a public drinking water distribution system. Nitrite in drinking water poses an acute health concern, causing serious illness and sometimes death in infants less than six months old from methemoglobinemia (blue-baby syndrome). Nitrification can also cause a loss of the disinfectant residual in the water, leading to other bacteriological problems. Lee County's nitrification surveillance practice easily and rapidly monitors for, detects, and confirms nitrification occurrence in a drinking water distribution system, thus allowing a public water utility to execute timely countermeasures. Although nitrification countermeasures are known and available, an easy, fast, and inexpensive early warning system was sorely lacking. This practice fills that void.

The goal of this program is to detect nitrification in drinking water in order to protect infants under six months old from methemoglobinemia and prevent other consequential bacteriological problems.

The health department trained field staff to watch for symptoms of nitrification, such as a sharp, unexpected decrease in total chlorine residual or an unexpected decrease in pH. If such symptoms are observed, then staff conducts a one-minute nitrate/nitrite field test using water quality test strips. If the test strip qualitatively confirms nitrification, then staff immediately notify the water utility so that they can 1) take countermeasures and 2) collect a water sample to obtain a certified laboratory analysis of nitrite and nitrate. The certified laboratory results are used to determine whether public notification is warranted.