Inactivation of cryptosporidium through chlorine-chloramine disinfection

摘要

For its unfiltered Hetch Hetchy water,the San Francisco Public Utilities Commission (SFPUC) is changing its current disinfection practice from chlorination only to chlorination (for giardia/virus inactivation) followed by chloramination (for residual disinfection.) While the drivifng force behind this change is to reduce disinfection by-product levles,there is some indication that cryptosporidium inactivation may be realized through the synergistic effects of chlorine followed by chloramine.