Minnesota Officials Warn Flooding Poses Risks to Private Drinking Water Wells
MINNESOTA — As recent flooding threatens private drinking water wells, health officials are urging well users to take immediate precautions to prevent contamination. If floodwater has reached your well, it is essential to assume that your well is contaminated and take the necessary steps to ensure your water is safe for use.
Immediate Actions for Well Owners
Assume Contamination: If floodwater has come into contact with your well, do not use the water for drinking, cooking, or brushing your teeth until the floodwater has receded and the well has been properly inspected and disinfected.
Avoid Electrical Hazards: Before approaching a flooded well, ensure that the well is completely disconnected from its power source to prevent electrical shock.
Inspection and Cleaning: If there is any indication that floodwater has entered your well, contact a licensed well contractor to inspect the well. The contractor will clean out any sediment or debris and disinfect the well with a chlorine solution. Attempting to use the well pump to remove debris could damage the pump. For a list of licensed well contractors, you can check out the following directory provided by the State of Minnesota: Licensed Well and Boring Contractor Directory.
Disinfection Process: Even if floodwater did not enter the well, it is recommended that it be disinfected as a precaution. Detailed instructions for disinfecting flooded private water wells are available on the Minnesota Department of Health (MDH) website.
Testing and Safety Confirmation
Water Testing: After the well has been disinfected and the chlorine solution has been pumped out, contact your county health department or an MDH-accredited laboratory to test your well water for coliform bacteria. They will provide instructions for submitting a water sample. You can find a list of accredited labs from the State here: Accredited Labs in Minnesota Accepting Samples from Private Well Owners (PDF).
Positive Test Results: If your well water tests positive for coliform bacteria, you will need to repeat the disinfection and testing process. This may need to be done multiple times until the water is confirmed to be free of bacterial contamination.
Lab Confirmation: Do not use the well water until you receive confirmation from the lab that the water is safe and free of bacterial contamination.
Precautionary Measures
Proximity Concerns: If floodwater came within 50 feet of your well but did not reach it, MDH recommends testing your well water for coliform bacteria as a precaution. Disinfection before testing is not necessary unless the test returns positive for bacteria.
For more information on protecting your well and ensuring your water is safe, contact the MDH Well Management Section at health.wells@state.mn.us or 651-201-4600 or 800-383-9808. Additional resources and detailed guidelines can be found on the Natural Disasters and Private Wells page on the MDH website.
Stay Safe and Vigilant
The Minnesota Department of Health emphasizes the importance of taking these precautions to protect your health and safety during flood events. Ensuring your well water is contamination-free is critical to preventing waterborne illnesses and maintaining safe drinking water.
Cover photo credit: Center of Disease Control
Written by: Will Wight
