Flood Recovery Resources for Clean Water and Mold Control



Major flooding and other disasters can lead to drinking water contamination and mold issues inside homes. Pesticide products known as antimicrobials may play a role in cleanup and decontamination measures following a flood. Antimicrobials work by killing or slowing the growth of microorganisms. The Center for Disease Control (CDC) and the National Pesticide Information Center (NPIC) have many resources available to educate flood victims about safe water and mold control concerns.

Never use water from unsafe sources.

After an emergency, especially after flooding, drinking water may not be available or safe to drink.

  • If you know or suspect your water is unsafe, don’t use that water to drink, wash dishes, brush your teeth, wash and prepare food, wash your hands, make ice, or make baby formula.
  • Never use water from radiators or boilers that are part of your home heating system
  • Do not use contaminated well water. Floods and other disasters can damage drinking water wells and lead to aquifer and well contamination. Floodwater can contaminate well water with livestock waste, human sewage, chemicals, and other contaminants that can lead to illness when used for drinking, bathing, and other hygiene activities. Dug wells, bored wells, and other wells less than 50 feet deep are more likely to be contaminated, even if damage is not apparent.
  • If extensive flooding has occurred or you suspect a well may be contaminated, DO NOT drink the water. Use a safe water supply like boiled, bottled or treated water for drinking, cooking and personal hygiene.
  • Contact your local, state, or tribal health department for specific advice on wells and testing.

IMPORTANT: Water that has fuel, toxic chemicals, or radioactive materials in it will not be made safe by boiling or disinfection. Use bottled water or a different source of water if you know or suspect that your water might be contaminated with fuel or toxic chemicals.

Making water safe.
  • Boil. Boiling water is the surest method to kill disease-causing germs, including viruses, bacteria, and parasites.
  • Disinfect. You can make small quantities of water safer to drink by using a chemical disinfectant, such as unscented household chlorine bleach, iodine, or chlorine dioxide tablets.
  • Filter. Many portable water filters can remove disease-causing parasites such as Cryptosporidium and Giardia from drinking water.
  • UV Light. Ultraviolet light can be used to kill some germs. Portable units deliver a measured dose of UV light to disinfect small amounts of clear water. It does not work well on cloudy water because particles may block the UV light from eliminating germs.
  • Solar Disinfection. The sun’s rays can improve the quality of water and may reduce some germs in the water.




Learn about places inside and outside of your home where you might find other sources of water that is safe to use.

For more information: Disinfecting Wells After a Disaster



Topics Covered

  • Clean Drinking Water Resources
  • Controlling Mold
  • Antimicrobials in Drinking Water