A properly constructed and maintained water well can provide many years of trouble free service, but a well can deteriorate or become damaged allowing surface contaminants to enter the water in the well. In addition, groundwater can become contaminated. The safety of a family’s drinking water is very important, so important that public water systems must monitor their water’s safety at least monthly. However, if you have a private well, regular testing is your responsibility.
Annual Inspection and Testing
Annual inspection and testing of your well and its water is very important. The spring is the best time to test your well’s water. Illinois receives its largest amounts of rainfall from April through June. During periods of higher rainfall, surface water may pick contaminants, such as bacteria, nitrates, or pesticides. If the upper part of your well has any cracks or leaks, this contaminated water could find its way into your well. Other times you need to test the well’s water would be after your well has been opened, under water or has been in a fire.
Testing for bacteria and nitrates at least once per year is the recommendation in Illinois. To check for bacterial safety, coliform bacteria levels are tested. These bacteria do not usually cause disease or illness, but their presence indicates surface contamination has found its way into your well and disease causing organisms may be present.
Nitrogen in the form of nitrates is a common contaminant in Illinois groundwater. An elevated nitrate level is often caused by a malfunctioning septic system, animal manure, or runoff from farm fields. High nitrate levels in drinking water are a concern for children less than 6 months old.
Testing Resources
Coliform bacteria and nitrate testing can be done by most local Illinois public health departments. To find your local county health department, visit the Illinois Department of Public Health (IDPH) alphabetical listing of Local Health Departments. You can also locate your local health department by county on the IDPH online regional map. Consult with your local health department to see if you should be testing for other contaminants such as volatile organic compounds (fuels and oils), heavy metals, etc. Certified labs can also test well water and may be your only option for certain chemicals.
Careful water sampling is required to get accurate results from the water testing kit that you received from the local county health department or from a certified lab. Read and follow all the instructions included in the testing kit.
More information on private well water testing can be found on the Illinois Environmental Protection Agency, Well Water Testing website, by contacting your local health department, or the Illinois Department of Public Health at (217) 782-5830.