Which pathogens are addressed by the Surface Water Treatment Rule?

The Surface Water Treatment Rule (SWTR), established by the Environmental Protection Agency (EPA), particularly focuses on addressing pathogens commonly present in surface water supplies, which includes lakes, rivers, and reservoirs. The correct choice highlights Legionella and Cryptosporidium as significant pathogens targeted by this rule.

Cryptosporidium is a protozoan parasite that can cause gastrointestinal illness, and it is a major concern because it is resistant to disinfection processes commonly used in water treatment, such as chlorination. This resistance underscores the need for effective treatment protocols that the SWTR mandates, including filtration and disinfection techniques specifically aimed at removing or inactivating this parasite.

Legionella, on the other hand, is a bacterium that can lead to severe pneumonia, known as Legionnaires' disease. While it is traditionally associated with water systems like cooling towers and plumbing, the rule's provisions include guidelines to mitigate risks associated with this bacteria in surface water sources as well.

The focus of the SWTR on these pathogens illustrates the rule’s intent to safeguard drinking water by reducing the risks of waterborne pathogens that can cause significant illness in the population. Therefore, the correct response emphasizes the importance of addressing both Cryptosporidium and Legionella as part of comprehensive water