Bacteria Testing

Bacteria Testing

Bacteria is a common microbial contaminant that can be introduced into ground water through a combination of well construction characteristics, intense rain events, surface to groundwater geologic pathways, and various surface activities. A common test for bacteria is the "total coliform bacteria" test.

A positive test reveals total coliform bacteria present and is an indication that you should not consume the water without boiling it first for 1 minute at a rolling boil. Boiled or bottled water should be used for drinking, cooking, dishwashing, food preparation, making ice and coffee, mixing baby formula
and brushing teeth.

What is a bacteria test and what does it tell me?

A bacteria test checks for the presence of total coliform bacteria and fecal coliform bacteria. These bacteria are not normally present in deeper groundwater sources. They are associated with warm-blooded animals and are normally found in surface water and in shallow groundwater(less than 20 -40 feet in depth). These bacteria are not necessarily pathogenic bacteria that make people sick but are used as standard indicators of the safety of the water. If these bacteria are present, then the conditions are favorable for harmful bacteria to exist. While some people may be unaffected from drinking the water, many have symptoms of stomach and intestinal illness, diarrhea, etc., especially the young, the old and immuno-compromised individuals.

What do I do if bacteria are found in my well?

The recommendation is to disinfect the well by thoroughly chlorinating it and then re-testing it once the chlorine is flushed out. In the meantime, do not use the water for drinking or cooking unless it is first boiled for one minute. What happens if the bacteria return after chlorination? If there is a return of total coliform bacteria, you can either have the well repaired or install a water treatment system such as a chlorinator or an ultra-violet light system. If fecal coliform bacteria returns, it is recommended to either repair the well or replace it. Disinfection treatment is not considered an acceptable remedy for wells with confirmed fecal coliform Bacteria.