ASCE has honored Gulizhaer Abulikemu; Jatin H. Mistry; David G. Wahman; Matthew T. Alexander; Alison R. Kennicutt, Ph.D., A.M.ASCE; Jacob D. Bollman; and Jonathan G. Pressman with the 2024 Wesley W. Horner Award for the paper “Investigation of Chloramines, Disinfection Byproducts, and Nitrification in Chloraminated Drinking Water Distribution Systems,” published in the October 2022 issue of Journal of Environmental Engineering.
In this work, the researchers examined four chloraminated drinking water distribution systems (CDWDS) required to maintain numeric versus “detectable” residuals that were spatially and temporally sampled for water quality and associated trihalomethane (THM) and haloacetic acid (HAA) formation. Monochloramine decreased from entry point (EP) to maximum residence time (MRT) samples, while THMs and HAAs initially increased and then stabilized or slightly decreased. Subsequently, EP and MRT samples were used in laboratory-held studies to further evaluate disinfectant residual stability, chloramine speciation, and nitrification occurrence. MRT water exhibited a faster monochloramine concentration decline than EP water did, indicating a decreasing disinfectant residual stability from increasing water age through distribution. Using a simple technique based on published inorganic chloramine chemistry, samples were also investigated for nondisinfectant positive interference (NDPI) on total chlorine measurements. NDPI concentrations represented up to 100% of the total chlorine concentration when total chlorine concentrations decreased to 0.05 mg-Cl2=L, indicating that little to no effective disinfectant residual remained.
The Wesley W. Horner Award recognizes papers that have contributed to the areas of hydrology, urban drainage, or sewerage.
