What percentage of Giardia and viruses must be removed according to the Surface Water Treatment Rule?

The correct percentage for the removal of Giardia and viruses according to the Surface Water Treatment Rule is indeed 99.99%. This regulation is essential for ensuring the safety of drinking water sourced from surface water supplies. Giardiasis and viral diseases can cause significant health issues, so the treatment processes for water must be robust enough to eliminate nearly all pathogens.

The Surface Water Treatment Rule was established to protect public health by requiring water treatment facilities to employ methods that achieve this high level of pathogen removal. Achieving 99.99% removal means that only a minuscule fraction of the microorganisms can remain, significantly reducing the potential for waterborne diseases. This stringent requirement reflects the critical nature of safe water treatment practices and the need for comprehensive treatment systems that include filtration and disinfection processes.

Given the public health implications and the effectiveness of advanced water treatment technologies, the requirement emphasizes the importance of maintaining rigorous treatment standards to protect consumers.