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How do chloramines differ from chlorine alone in water disinfection?

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A labeled diagram of the chlorine element from the periodic table shows its atomic number 17, symbol Cl, electron configuration, and atomic weight range. The box is shaded green to indicate chlorine is a halogen, with icons for orthorhombic crystal structure, gas state at room temperature, and strong acidity. A key explains the icons and colors used. — chlorine Properties of chlorine.

Chloramines, which are formed by combining chlorine with ammonia, differ from using chlorine alone in several key ways regarding water disinfection:

Longevity: The disinfecting effect of chloramines lasts longer than that of chlorine alone, which helps maintain water quality throughout the distribution system.1
By-products: Chloramination produces lower levels of harmful by-products, such as chloroform and other trihalomethanes, compared to the use of chlorine alone.1
Taste and Odour: The use of chloramines further reduces taste and odour problems in treated water.1

While both methods are used to destroy pathogenic bacteria and prevent waterborne disease, chloramines are increasingly utilized in public water supplies to provide these specific advantages over traditional chlorination.12