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Wisconsin Department of Health Services

Water Issues

Drinking Water | Disinfecting Your Well and Water System | Sewer/Waste Water Concerns | Flood Waters

When outside do NOT swim or bathe in rivers, streams, creeks, or lakes in flooded areas!

Drinking Water

  • Municipal water users:  Turn on and run faucets for at least five minutes before using water for drinking or food preparation. 
    • If a "boil water" notice is issued, follow any directions given by the Department of Natural Resources.


  • Private Well Owners:  Do not use water from a private well that has been or is flooded. 
    • If you are not certain about the safety of your water supply you should have the well tested for bacteria.
    • Whenever you notice a change in water quality, or anytime there’s been flooding near your well, have your well tested for bacteria contamination. 
    • For information on how to sample your water, go to the DNR web pages.
    • If contamination is found, disinfect your well/water supply.  
    • Until the test results are known, there are procedures you can follow to ensure safe drinking water:  
      • Drink bottled water or water from a known, safe, source. 
      • If necessary, you can make water safe to drink by boiling the water for five minutes.
  • When in doubt, if the water is CLOUDY, ODOROUS, COLORED - DO NOT DRINK THE WATER!

For more information, go to the Water Issues page.

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Disinfecting Your Well and Water System

Private wells can become contaminated in a number of different ways (flooding, insects, soil entry, etc.). Whenever you notice a change in water quality, or anytime there has been flooding near your well, have your well sampled for coliform bacteria contamination. Coliform bacteria are indicators of surface water or fecal (sewage) contamination. When this occurs, the well and water system will need to be disinfected.

Once an inspection has determined that your water system is free from any sources of apparent contamination, you should disinfect the well.

The Wisconsin Department of Natural Resources website provides procedures for well disinfection:

For more information, contact your Local Public Health Department.

Sewer/Waste Water Concerns

  • Private septic systems that have been flooded are no longer reliable. Portable toilets or other appropriate facilities should be used. Remember, you should not have contact with water that has been contaminated with human wastes.  Additional information about septic systems affected by a flood (exit DHS) are available.

  • If water and sewage disposal are not working, use portable toilets, or facilities at the emergency site.

  • Sewage may back flow from your septic or municipal system through floor drains, toilets, etc. Any affected areas, such as basements, must be cleaned and disinfected, as with a chlorine solution. Anything that cannot be cleaned should be thrown out.

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Flood Water Hazards

Do NOT swim or bathe in rivers, streams, creeks, or lakes in flooded areas!  Flood waters have unseen hazards such as debris, chemical and sewage contamination, and strong current. Taking a few simple precautions during and after a flood will help keep your children safe. 

  • To protect yourself, minimize the impact of flooding on your health, safety and property. (exit DHS) 
  • In case of water damage, contact your local public health department for a list of plumbers and a flood brochure.
  • If you receive a cut or puncture wound while cleaning your home, tetanus shots are available through the Local Public Health Department.
  • Don't let children play in or near flood water, or in areas that have been recently flooded.
  • Wash your child's hands frequently, especially before meals.
  • Disinfect toys that may be contaminated, using a solution of eight ounces (one cup) of bleach in one gallon of water.
  • Discard any soft toys that may be contaminated with sewage. Young children may put these items into their mouths.

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Last Revised: March 19, 2014