AWWA ACE70894

This poster paper presents a study to better identify and quantify chloramine decay mechanisms and their relationship to supporting nitrification in distribution systems. This objective will be obtained using the CDWQ distribution system water quality model, field data collected from participating utilities, and data gathered from laboratory pilot studies. Chloramines participate in numerous reactions that diminish residual concentrations during distribution while releasing ammonia in the distribution system, supporting nitrification. A reaction model for free chlorine and chloramines was developed as part of a distribution-system water-quality model, called the Comprehensive Disinfection and Water Quality (CDWQ) model. CDWQ was calibrated using data from a year-long distribution system sampling program conducted at United Water of New Jersey (Woolschlager 2000; Woolschlager et al., 2001). Includes figures.