Journal Guest: Limited access

Monochloramine Cometabolism by Nitrifying Biofilm Relevant to Drinking Water

  • Author(s): Wahman, David G.; Maestre, Juan P.; Speitel, Gerald E., Jr.
  • Publications: Journal - American Water Works Association
  • Issue Date: July 2016
  • Volume / Number: 108, Number 7
  • Page(s): E362-E373
  • DOI:
  • Product Number: JAW_0083304
Full Text: pdf

Non-Member Price: $30
Free Download -- a benefit for AWWA members (login required)


Biological monochloramine removal (i.e., cometabolism) by a pure culture ammonia-oxidizing bacteria - Nitrosomonas europaea - and a nitrifying mixed culture have recently been shown to increase monochloramine demand. Although important, these previous suspended-culture batch kinetic experiments were not representative of drinking water distribution systems, where bacteria grow predominantly as biofilm attached to pipe walls or sediments, and physiological differences may exist between suspension and biofilm growth. The current research made an important next step in extending the previous results by investigating monochloramine cometabolism by biofilm grown in annular reactors under conditions relevant to drinking water. Estimated monochloramine cometabolism kinetics were similar to those of ammonia metabolism, and monochloramine cometabolism was a significant loss mechanism (30-40% of the observed monochloramine loss). These results demonstrate that monochloramine cometabolism occurred in nitrifying biofilm relevant to drinking water; thus, cometabolism may be a significant contribution to monochloramine loss during nitrification episodes in distribution systems.

AWWA Members

Download the online article for free (login required).

Non Members

Select ADD TO CART to purchase the article (login required) or select JOIN AWWA and enjoy the benefits of membership, including accessing this article for free.