Advances in Treatment Processes to Solve Off-Flavor Problems in Drinking Water

There have been significant advances in the development and application of treatment processes to control off-flavor problems in drinking water in the past few years. This paper updates two major treatment process summaries that appeared in 1988 and 1995. The paper also puts the efficiencies of the treatment processes in perspective by using the drinking water flavor wheel as a reference point. Removal or control of classes of off-flavor problems are described in relation to the categories on the wheel. Specifically, processes such as oxidation, adsorption, biological treatment and membranes are described. The recent literature is reviewed and advances in treatment are identified. A new treatment process for controlling nitrification in distribution systems is introduced which has the potential to dramatically reduce the problems of chlorinous odor complaints from customers.