Staff Guidance for Public Water Systems: Treatment Issues


Topics Under This Category:
Alternate Disinfectants: Standby Units and Spare Parts
Conditions under which public water systems that use one of these alternate disinfectants do not have to provide duplicate disinfectant facilities: chloramines, ozone, or chlorine dioxide.
 
Meeting Treatment Technique Requirements for Cryptosporidium, Giardia, and Viruses
Information for our staff to use when reviewing these filtration methods: membrane filtration; two-stage filtration; direct filtration; cartridge filtration.
 
Selection of Baffling Factors and Operating Conditions for T10 Calculations
When empirical data are unavailable, use these methods to determine values to use for the baffling factor, basin volume, and flow rate when calculating T10 (the time it takes for 10 percent of the water to flow through the basin).
 
Use of Chloramines
Procedures for obtaining approval to convert to chloramine disinfectant. To safeguard dialysis patients, customers must be notified before the change occurs.
 
Use of Chlorine Dioxide
Procedures to follow to convert a public water system's disinfectant from chlorine to chlorine dioxide.