Total Coliform Bacteria

Coliforms are bacteria that are naturally present in the environment and are used as an indicator that other, potentially-harmful, bacteria may be present.

PUBLIC WATER SYSTEMS - Please consult the Ohio EPA.

PRIVATE WATER SYSTEMS w/ CONTINUOUS DISINFECTION -  Private water systems using continuous disinfection such as shallow wells, rainwater cisterns, springs, or ponds, or for hauled water storage tanks that receive water from a public water supply, the lab results for a 100 ml water sample shall have: -No detection of any total coliform colony forming units (CFUs) or less than 1 most probable number (MPN). -No detection of E. coli (less than one CFU or MPN) The absence of total coliform and E. coli in a water sample is a good indicator that a disinfection system is functioning properly.

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Groundwater (underground drinking water) in a properly constructed well should have minimal-to-no coliform bacteria. If coliform are found in a well it generally means bacterial and mineral slimes have built up and your well needs to be professionally cleaned by a registered private water system contractor. Homeowners who use cisterns, springs or ponds as a drinking water source should use treatment devices to disinfect and filter the water to remove coliform bacteria. The presence of total coliform in a water sample means the disinfection system is not working properly. Improperly maintained treatment devices can be sources of contamination. Home water filters and other water-treatment devices should be changed and maintained in accordance with manufacturer's recommendations. For Water Wells Continuous disinfection may be installed on properly constructed private water wells. In Ohio continuous disinfection is not permitted to be installed on improperly constructed wells, or wells in poor, deteriorated condition. Improperly constructed wells or wells in poor condition with the inability to obtain acceptable levels of total coliform, fecal bacteria, or E. coli should be properly sealed.

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