Disinfection of the final effluent takes place prior to discharge from the WPCF. At Norwalk WPCF, a strong bleach solution (sodium hypochlorite) is used to effectively kill pathogens and helps meet regulatory standards for water quality. A second chemical (sodium bisulfite) is then used to neutralize the bleach prior to discharging the clean water to the Norwalk River in accordance with its state-issued permit and applicable water quality standards.

Disinfection & Dechlorination