E. coli

One of hundreds of strains of the bacterium Escherichia coli, E. coli O157:H7 is an emerging cause of food-borne and water-borne illness. Most strains of E. coli are harmless and live in the intestines of healthy humans and animals and consequently, provide an excellent fecal indicator.

Infection often causes severe bloody diarrhea and abdominal cramps; sometimes the infection causes non-bloody diarrhea. Frequently, no fever is present. It should be noted that these symptoms are common to a variety of diseases, and may be caused by sources other than contaminated drinking water.

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E. coli

Contaminant group: 
Major sources in drinking water: 
Human and animal fecal waste
Treatment options: 

Prior to providing treatment options, the source of fecal coliform or E. coli contamination should be determined and the cause of the contamination removed. Once the contamination has been eliminated as a threat to the water supply, disinfection of the private water system should be performed and the water re-sampled. It is recommended that the water from a private water system be tested for total coliforms and E. coli periodically in order to determine the need for maintenance, repair, or replacement. When the presence of E. coli is recurrent, it is not recommended that continuous disinfection be used in place of removing of the cause of contamination or repairing or replacing the private water system.

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