COLIFORM BACTERIA FACT SHEET
 
Brief Overview:
Contaminant: Total Coliform Bacteria
Category: Microbiology
MCL: 0
Source: Fecal matter, surface and runoff water
Effect: Intestinal disorders, cholera, typhoid fever
Followup: Total Coliform, E. coli, and Enterococci; Inspect well
Treatment: UV Purifier, Chlorinator, (boil water, temporarily)

Details:
Source:
Total coliform sources include human or animal fecal matter, surface water (lakes, streams etc.) and water that contacts soil. Some ways that contamination can reach a water supply are: a broken or missing well cap; openings which could allow small animals to enter or fall in the well; breaks in underground pipes or well casing; malfunctioning septic systems or broken sewer lines; contamination of aquifer by sink holes, abandoned wells, or other geological factors; poor well construction or inadequate grouting of the well.

Effect:
Coliform bacteria analysis is used to determine the sanitary condition of a well or spring. The presence of Coliform bacteria indicates the water supply is unsafe and may cause illness. Coliform is a group of bacteria found in both waste water and surface water. Coliform itself (with the exception of certain kinds of E. coli) is not necessarily harmful, however its presence indicates the likelihood of other kinds of bacteria which are harmful.

Followup:
The recommended follow-up is a test for total coliform, E. coli and enterococci (another indicator of fecal matter) to determine if the contamination is from surface water source (run-off, stream, etc.) or from a fecal source (septic system, sewer line, barnyard). Also recommended is a well or spring inspection. The well inspection is a physical check of the well for physical defects. (defective casing, well cap defective, leaking pitless well adaptor, insect or animal entry, etc.)

Treatment:
Boiling water for one minute at a rolling boil can be used as a temporary measure. The most commonly installed treatment equipment is an Ultraviolet (UV) purifier or a chlorinator. Other treatment methods not so common: Iodine injection, Ozone, Bromine, Silver, Micro filtration or reverse osmosis. Some portable filters (camping, hiking, etc.) use a combination of technologies and are labeled as purifiers. Well (or shock) chlorination is a temporary measure NOT recommended when you are selling your home unless you are absolutely certain that the source of contamination has been eliminated.