What Causes E. Coli in Well Water?

Escherichia Coli is a rod-shaped bacterium commonly abbreviated to E.coli. It is commonly found in the intestine of warm-blooded organisms and is harmless in most cases -- being a natural part of the normal inhabitants of the gut - but some strains can be extremely harmful, causing severe cases of food poisoning and even death. E.coli can survive for some time out of its host, so it is easy to transmit. The most common form of transmission is orally through the ingestion of fecal matter.

Sewage

• E.coli is transmitted through the ingestion of fecal matter and untreated sewage can be one of the leading causes of contamination of well water. Untreated sewage can seep through the water plain and contaminate water that may subsequently be drawn into a private or public water well.

Animals

• Animal fecal matter is the other main cause of E.coli in well water. Animals may directly deposit matter into the well or their fecal matter seeps into the soil with the rain, and gradually finds its way into the well water. In addition, matter from dead animals can also find its way into the water system.

Testing

• It is impossible to ever be sure that well water is free from E.coli contamination and therefore, regular testing should be carried out. People can contact their local laboratory testing officer and arrange to have a water sample sent to the lab. If E.coli is found, the well should be thoroughly disinfected and then the water re-tested again to ensure its safety.

Precautions

• To guard against the contamination of well-water with E.coli, wells should be left covered at all times when not in use, to prevent the inadvertent pollution of the water from animal feces. Birds droppings in particular can be a common source of transmission prevented by this method. Placement of the well is also important, and areas downhill from high animal agricultural activity should be avoided. The best method of prevention is the boiling of all water obtained from a well whose water quality is untested and unknown.