Pathogen Reduction Crediting: Its not what you can remove, it's what you can prove

Abstract

Key Takeaways

• Potable water reuse requires much higher pathogen reduction than conventional drinking water treatment.
• As with drinking water treatment, potable reuse is regulated by comparing the log₁₀ reduction value (LRV) requirements for pathogens with the LRV credits that can be achieved by the individual treatment processes in the facility.
• This LRV crediting approach is used because we are technically incapable of measuring pathogens in treated water down to the very low levels needed.
• Frameworks exist to assign pathogen LRV credits for some treatment processes; many other processes remain under-credited or entirely uncredited.
• To improve the efficiency and economics of potable reuse, existing crediting frameworks need to be expanded for under-credited processes and new frameworks need to be created for uncredited processes.