Frequently Asked Questions:

My well tested positive for coliform bacteria, will my water make me sick?

When drinking water tests positive for coliform bacteria it means that there is an increased chance that you could get sick.  A positive coliform test indicates that the drinking water is at risk for bacterial contamination.  A positive fecal coliform or E. coli result means that there is a direct fecal contamination of the water.  Fecal contamination of water results in a much higher risk of disease such as giardiasis or Salmonella.


Algae: A group of chiefly aquatic organisms (some microscopic) and nonvascular plants that contain chlorophyll. Green chlorophyll color can be sometimes masked by brown or red pigments.

Aerobic: Occuring in the presence of oxygen.

Anaerobic: Occuring in the absence of oxygen.

Bacteria: Any of a group of microscopic, unicellular, organisms having a cell membrane and non-nucleated DNA (Prokaryotic).

Chain of Custody (COC):  Reference to the documentation, or paper trail, that shows the seizure, custody, control, transfer, and analysis requests of a submitted sample. 

Coliform Bacteria:  a: A non-related group of bacteria that are used as an indicator of contamination in food and water.  b: Gram negative, rod shaped bacteria that ferment lactose producing gas and acid at 35C. 

Colony Forming Units (CFUs):  A rough estimate of the number of viable bacteria or fungal cells in a sample.

Disinfection:  The destruction or prevention of growth of micro-organisms.

E. coli: A specific fecal coliform that is predomiantly found in the intestines of warm blooded animals.  Often used to indicate level of fecal contamination.

Fecal Coliforms: a: Coliforms considered to be of fecal origin.b: Coliform bacteria that can ferment lactose at 44.5C producing acid and gas.

Fungi: Any of a major group of saprophytic and parasitic lower plants that do not have chlorophyll and includes molds, rusts, mildews, smuts, mushrooms, and yeasts.

Indicator Organisms: Organisms that are used to indicate a specific condition. ie. The presence of E. coli in water indicates that the water has been contaminated by fecal matter.

g: grams

Microscopic Particulate Analysis (MPA): A test method designed by the EPA to determine the risk of surface water contamination of ground water used for drinking.

mL: milliliters

Mold: Name given to multiple celled fungi that have a filamentous growth. 

Most Probable Number (MPN): Test method of quantitatively estimating an analyte level using a statistical equation. 

Safe Drinking Water Act (SDWA): The main federal law that ensures the quality of Americans’ drinking water.  Under SDWA, EPA sets standards for drinking water quality and oversees the states, localities, and water suppliers who implement those.  More Info at EPA’s SDWA website .

Sanitization: A process which reduces microbial numbers to a designated safe point.

Sterilization: A process, physical or chemical, that destroys or eliminates all organisms. 

Toxic Mold:  Mold that produces toxic chemicals (mycotoxins) while growing.  Mycotoxins can be contained in the mold itself and or the spores.

Yeast: Name given to microscopic single celled fungi.