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Why can chloramines reduce taste, odour, and harmful by-products in treated water?

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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, are increasingly used in water treatment because they offer distinct advantages over using chlorine alone.

When used for disinfection, chloramines provide a longer-lasting effect, which helps maintain water quality throughout the distribution system. Compared to the use of chlorine alone, chloramination results in lower levels of harmful by-products and further minimizes issues related to taste and odour in treated water.1

While chlorine is effective for disinfection, it can react with naturally occurring organic compounds to produce potentially harmful by-products such as trihalomethanes. By utilizing chloramines, water treatment facilities can effectively disinfect water while mitigating these specific chemical risks and sensory concerns.12