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C-FERST Issue Profile: Microbes in Water

Microbes are tiny organisms that can be found everywhere on the planet, including our air and water. Most microbes are harmless, or even beneficial to people, however some can be harmful.

Microbes that can contaminate drinking water include bacteria such as E. coli, or parasites such as Giardia. Sources of microbe contamination include nonpoint sources such as land runoff or precipitation, septic systems, stormwater runoff and combined sewage overflows. Negative health effects that can result from drinking water with microbe contamination range from gastrointestinal illness (diarrhea, vomiting, cramps) to Legionnaire's Disease (a type of pneumonia). Microbial drinking water contamination is regulated by EPA under the Safe Drinking Water Act.

To learn more about drinking water issues related to microbe contamination, visit the links below.