AWWA ACE60025

A US-wide survey of raw and finished drinking water from 28 water treatment plants (WTPs) was conducted to investigate the occurrence and fate of dissolved organic nitrogen (DON) in the water treatment plants (WTPs). Average DON concentrations in raw drinking water were 0.202 and 0.171 mgN/L in May-June and October-December surveys, respectively. Average DON concentrations of raw and finished drinking water from the two surveys indicated an overall 20% DON removal across the full-scale WTPs. Average DOC/DON ratio was 20 mgC/mgN, and 50% of the samples have DOC/DON ratios between 14 and 23 mgC/mgN. Molecular weight analysis of DON has also been conducted, and DON fractionation roughly parallels DOC molecular weight distributions. Includes 9 references, table, figures.