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Which microorganisms can be killed during drinking-water disinfection?

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Diagram of a water treatment plant showing the process from water inlet through mixing, coagulation, flocculation, settling, filtering, chemical treatment with chlorine, storage, and high-lift pumping to the distribution system. — water purification Water from inlets located in the water supply, such as a lake, is sent to be mixed, coagulated, and flocculated and is then sent to the waterworks for purification by filtering and chemical treatment. After being treated, the water is pumped into water mains for storage or distribution.

Drinking-water disinfection is a critical public health process designed to destroy pathogens—disease-causing microorganisms—that pose a threat to human safety.12

While the primary goal of disinfection is to eliminate pathogenic bacteria, the broader process of water purification is responsible for reducing the concentration of various biological contaminants, including:

Bacteria: Pathogenic strains that cause waterborne diseases.123
Viruses: Microscopic infectious agents that can be removed or inactivated during treatment.3
Parasites: Organisms that may be present in raw water sources.3
Fungi: Microscopic organisms that can be reduced through purification procedures.3

These contaminants are typically addressed using methods such as chlorination, ozone, or ultraviolet radiation. By destroying these microorganisms, water treatment systems effectively prevent the spread of waterborne illnesses and ensure the safety of public water supplies.24