Regulatory Limits for Coliform Bacteria in Pennsylvania Well Water

Pensylvania is one of the few states that does not impose regulations on the quality or testing of private well water. A 2009 study funded by the Center for Rural Pennsylvania found that some 20,000 private wells are added in the state each year. You can voluntarily have your well water tested for coliform bacteria if you are concerned about contamination. If bacteria is found, treating the water and repairing any damage to your well can eliminate the contaminants.

What is Coliform Bacteria?

• Coliform bacteria is considered an indicator organism; it indicates the potential presence of other contaminants. The bacteria is found in human and animal stool, and its presence is a good indicator of fecal contamination. The most common strain of coliform bacteria is E. coli, which is only found in feces.

Health Risks

• Generally, coliform bacteria is not harmful by itself and the main concern with its presence is the potential for other organisms present in fecal matter to also have contaminated your well. However, ingesting large amounts of the bacteria can cause gastrointestinal symptoms such as nausea and diarrhea. In rare cases the bacteria can invade the organs, eyes or skin and cause damage, possibly resulting in death. The very young, very old and those with compromised immune systems are more susceptible.

Regulatory Limits

• Pensylvania does not impose any limits on the amount of coliform bacteria in private well water and does not require testing for wells. However, the Environmental Protection Agency has instituted the Total Coliform Rule which states that no more than 5 percent of samples taken from a water source over the course of a month can contain the bacteria.

Testing and Treatment

• To have your water tested, contact your local Department of Health. If testing shows that your well water contains coliform bacteria, you can treat the water with large amounts of chlorine. Your Department of Health should be able to recommend a local company to do this for you. You will also need to have your well inspected to determine where the contamination came from and to repair any cracks found.