AWWA WQTC63950

Control of nitrification is important to the success of implementing chloramines to comply with the disinfection byproducts regulations. The purpose of this study was to test strategies that will allow Tucson Water to use chloramines and avoid nitrification in their storage tanks and reservoirs. When chloramine concentrations were allowed to deteriorate in the demonstration-scale test system, nitrification occurred relatively quickly. When nitrification became established, the addition of more chloramines was ineffective and, in fact, counterproductive. The lesson from pilot and demonstration studies continues to be that prevention of nitrification is far more effective than control after the onset of nitrification. Preventative use of chlorite ion has been shown to be highly effective in both pilot- and demonstration-scale testing in Tucson water. Includes 3 references, figures.