Description: Chlorine disinfection is one of the most important processes used in drinking water treatment and distribution systems to protect public health. This one-hour webinar provides drinking water operators with an overview of chlorine chemistry, disinfection principles, and the practical calculations required for effective system operation. Participants will learn how chlorine works to inactivate pathogens, the factors that affect disinfection performance, and how to monitor and maintain proper disinfectant residuals throughout the treatment and distribution systems. The webinar will also cover common operator calculations related to chlorine dosage, feed rates, residual concentrations, and contact time (CT). Real-world examples and calculation exercises will help operators strengthen their understanding and confidence in applying chlorine disinfection concepts in daily operations.

Learning Objectives:

• Explain the purpose of chlorine disinfection and describe how chlorine protects public health by controlling waterborne pathogens.

• Identify key factors that influence chlorine disinfection effectiveness, including pH, temperature, contact time, chlorine demand, and residual concentration.

• Calculate chlorine dosage and feed rates for different forms of chlorine disinfectants using standard drinking water operator formulas and units of measurement.

• Determine chlorine residuals and CT values and apply these calculations to evaluate and optimize disinfection performance in drinking water systems.

Presenter: Daryl Gotham, P.E., Senior Research Engineer, Great Lakes Environmental Infrastructure Center

Certificate: This webinar has NOT been submitted for approval of continuing education credit. We can provide a certificate of attendance to eligible attendees, but cannot guarantee it will meet your PDH or CEU requirements.

Who Should Attend: 

• Managers, owners, and operators of small drinking water systems serving less than 10,000 people

• Decision-makers for drinking water utilities, including mayors, finance officers, utility managers, public works directors, city councilors, board members, tribal council members, and clerks

• Consultants and technical assistance providers serving drinking water systems

Partner: