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.