AWWA ACE59915

In order to comply with the regulations for disinfection byproducts, many utilities are utilizing alternative disinfectants, such as chlorine dioxide (ClO₂) and chloramines, and are minimizing free chlorine (Cl₂) contact time. This study investigated the ability or inability of ClO₂, Cl₂, and potassium permanganate to oxidize fishy/swampy/grassy odorants, and powdered activated carbon (PAC) to adsorb these compounds. ClO₂ was found to be a selective oxidant for the control of these types of taste-and-odor problems, whereas maintaining some free Cl₂ contact time (e.g., through the filters) or use of permanganate or PAC may be needed if prechlorination is eliminated. Includes 12 references, table, figures.