Minnesota urges private well owners to avoid floodwater contamination

May 1, 2023
The Minnesota Department of Health is sharing recommendations for preventative actions that private well owners can take to reduce contamination by floodwaters.

As communities around the Minnesota prepare for spring flooding, the state’s Department of Health (MDH) is reminding private well owners and users of the importance of taking preventive action to reduce the possibility of their drinking water becoming contaminated by floodwaters.

Wells contaminated with floodwater pose a health risk, but the impact floodwaters have on wells and water quality are often not as visible as other flood damage. With that in mind, MDH is offering well users the following recommendations:

  • If your well is in a flood-prone area and you have time, consider contacting a licensed well contractor to check your well and make any necessary repairs or changes to help protect it from flooding. These changes may include repairing cracked or damaged casing, extending the well casing above the expected flood level or temporarily replacing the vented well cap with a watertight cap or cover. You should also make sure that grading allows water to flow away from your well.
  • If you think your well might become flooded, store a supply of clean water that will last for at least a few days. Shut off power to the well pump to avoid having floodwater pumped into your plumbing system or home. If you only have a little time before a flood, you can cover the well with a heavy plastic bag or sheeting and secure it with electrical tape. This won’t completely protect your well from contamination, but it will help reduce the amount of water and debris that could enter your well, making clean up easier.
  • If floodwater reached your well, assume the well is contaminated. Water from your well should not be used for drinking, cooking or brushing your teeth until the floodwater recedes and the well has been disinfected and cleaned. If floodwater came within 50 feet of your well – but did not reach the well – MDH recommends that users have their well water tested for coliform bacteria as a precaution.