Water Protection Program fact sheet
Division of Environmental Quality Director: Ed Galbraith

The Importance of Monitoring Free and Total Chlorine

Public health is protected when public drinking water systems properly disinfect with chlorine and sufficiently monitor for free and total chlorine residuals. These two measures decrease the risk of public exposure to E. coli and other pathogens. In addition, they reduce the liability of water systems as well as the potential need for boil water orders and other public notice requirements. However, the importance of one measure does not outweigh the other. The department’s data shows drinking water systems that chlorinate are far less likely to issue boil order notices when they monitor chlorine routinely and maintain residuals at required levels. All systems that add chlorine are required to measure chlorine residuals. Refer to 10 CSR 60-4.080 for frequency.

Drinking water systems required to chlorinate include:

Tips for successful chlorination and monitoring of chlorine residuals

Chlorine residual requirements

Please contact a regional office for further information and assistance.

Kansas City Regional Office             816-251-0700
Northeast Regional Office                  660-385-8000
Southeast Regional Office                  573-840-9750
Southwest Regional Office                 417-891-4300
St. Louis Regional Office                   314-416-2960