Flood Health and Safety

This page has been automatically translated from English. MSDH has not reviewed this translation and is not responsible for any inaccuracies.

Water Quality and Safety

Flooding can contaminate the public water supply. Drinking contaminated water may cause illness. You cannot assume that the water in the affected area is safe to drink. Water treatment plants may not be operating; even if they are, flooding can contaminate water lines. Listen for public announcements about the safety of the water supply. If your well has been flooded, it needs to be tested and disinfected after the flood waters recede. Contact the Division of On-site Wastewater at the call center number or at wastewater@msdh.ms.gov for questions about water testing.

Water for Drinking and Cooking

Safe drinking water includes bottled, boiled, or treated water. Your state health department can make specific recommendations for boiling or treating drinking water in your area. Here are some general rules concerning water for drinking and cooking:

  • Do not use contaminated water to wash dishes, brush your teeth, wash and prepare food, or make ice.
  • If you use bottled water, know where it came from. Otherwise, water should be boiled or treated before use. Drink only bottled, boiled, or treated water until your supply is tested and found safe.
  • Boiling water kills harmful bacteria and parasites; bringing water to a rolling boil for 1 minute will kill most organisms.
  • When boiling is not possible, water may also be treated with chlorine or iodine tablets, or by mixing six drops (1/8 teaspoon) of unscented, ordinary household chlorine bleach (5.25% sodium hypochlorite) per gallon of water. If the water is cloudy, use twelve drops (1/4 teaspoon). Mix the solution thoroughly, and let stand for about 30 minutes. These treatments will not kill parasitic organisms, however.
  • Containers for water should be rinsed with a bleach solution before re-using them. Use water storage tanks and other types of containers with caution. For example, fire truck storage tanks, as well as previously used cans or bottles can be contaminated with microbes or chemicals.
  • Do not rely on untested devices for decontaminating water.

Disinfecting Wells

If you suspect that your well may be contaminated, visit our private well disinfection page or contact your state health department or agriculture extension agent for specific advice.

Food Safety

General Precautions

  • Do not eat any food that may have come into contact with contaminated floodwater.
  • Discard any food not in a waterproof container if there is any chance that it has come into contact with contaminated floodwater.
  • Undamaged, commercially canned foods can be saved if you remove the can labels, thoroughly wash the cans, and then disinfect them with a solution consisting of one cup of bleach in five gallons of water. Re-label your cans, including expiration date, with a marker.
  • Food containers with screw-caps, snap-lids, crimped caps (soda pop bottles), twist caps, flip tops, snap-open, and home canned foods should be discarded if they have come into contact with flood water because they cannot be disinfected.
  • For infants who are not breastfeeding, use only canned baby formula. Do not use powdered formulas unless they are mixed with boiled and cooled water, or water known to be safe.

Frozen and Refrigerated Foods

If you will be without power for a long period:

  • Ask friends to store your frozen foods in their freezers if they have electricity.
  • See if freezer space is available in a store, church, school, or commercial freezer that has electrical service.
  • Use dry ice, if available. Twenty-five pounds of dry ice will keep a ten-cubic-foot freezer below freezing for 3-4 days. Use care when handling dry ice, and wear dry, heavy gloves to avoid injury.


It is critical to practice basic hygiene during the emergency period. Always wash your hands with soap and water that has been boiled or disinfected:

  • Before preparing or eating food
  • After toilet use
  • After participating in cleanup activities
  • After handling articles contaminated with floodwater or sewage

Floodwater may contain fecal material from overflowing sewage systems and agricultural and industrial waste. Although skin contact with floodwater does not, by itself, pose a serious health risk, there is risk of disease from eating or drinking anything contaminated with floodwater. If you have any open cuts or sores that will be exposed to floodwater, keep them as clean as possible by washing them with soap and applying an antibiotic ointment to discourage infection. If a wound develops redness, swelling, or drainage, seek immediate medical attention.

Do not allow children to play in floodwater areas. Wash children's hands frequently (always before meals), and do not allow children to play with floodwater-contaminated toys that have not been disinfected. You can disinfect toys using a solution of one cup of bleach in five gallons of water.


Flooding may lead to an increase in mosquitoes, which carry diseases such as West Nile virus, especially in the summer months. Clear your property of standing water as soon as possible, and use precautions against mosquitoes meanwhile.

Returning Home

When returning to your home after a flood:

  • Find out if the authorities have declared the area safe.
  • Watch for debris on the road while driving.
  • Make sure the main electrical switch to your home is off before entering the structure.
  • Be careful when entering a structure that has been damaged.
  • If you suspect a gas leak, leave immediately and notify the gas company.
  • If possible, listen to the radio or contact authorities to find out if sewage lines are intact before turning on the water or using the toilet.
  • Report utility damage to the proper authorities.

Gas Leaks
If you smell gas or suspect a leak, turn off the main gas valve, open all windows, and leave the house immediately. Notify the gas company, the police, fire departments, or State Fire Marshal's office, and do not turn on the lights, light matches, smoke, or do anything that could cause a spark. Do not return to the house until you are told it is safe to do so.

Electrical Damage
Your electrical system may have been damaged. If you see frayed wiring or sparks when you restore power, or if there is an odor of something burning but no visible fire, you should immediately shut off the electrical system at the main circuit breaker. All electrical equipment and appliances must be completely dry before returning them to service. It is advisable to have a certified electrician check these items if there is any question.

Other Injury-Prevention Measures
To avoid other flood-related injuries, you should avoid all power lines, particularly those in water; and avoid wading in water as broken glass, metal fragments, and other debris may be present in the water.

Once you have established that no structural, electrical, or gas-related hazards exist in your home, dry and disinfect all materials inside the house to prevent the growth of mold and mildew.

Walls, hard-surfaced floors, and many other household surfaces should be cleaned with soap and water and disinfected with a solution of one cup of bleach to five gallons of water. Be particularly careful to thoroughly disinfect surfaces that may come in contact with food, such as counter tops, pantry shelves, refrigerators, etc. Areas where small children play should also be carefully cleaned. Wash all linens and clothing in hot water, or dry clean them. For items that cannot be washed or dry cleaned, such as mattresses and upholstered furniture, air dry them in the sun and then spray them thoroughly with a disinfectant. Steam clean all carpeting. If there has been a backflow of sewage into the house, wear rubber boots and waterproof gloves during cleanup. Remove and discard contaminated household materials that cannot be disinfected such as wall coverings, cloth, rugs, and drywall.

Other Hazards

Downed Powerlines

Do not attempt to move or repair downed powerlines. Do not drive through standing water if downed powerlines are in the water.


Wild or stray domestic animals can pose a danger. Remember, most animals are disoriented and displaced, too. Do not corner an animal. If an animal must be removed, contact your local animal control authorities. If you are bitten by any animal, seek immediate medical attention. If you are bitten by a snake, first try to accurately identify the type of snake so that, if poisonous, the correct anti-venom can be administered. Do not cut the wound or attempt to suck the venom out.


Swiftly moving waters pose a great danger. People who enter moving water with their cars, or who get on boats are at a grave risk of drowning, regardless of their ability to swim. Even very shallow water that is moving swiftly can be deadly. Cars or other vehicles do not provide adequate protection. Cars can be swept away or may break down in moving water. Be alert and follow hazard warnings on roadways or those broadcast by the media. Police and public works departments should be contacted for up-to-date information regarding safe roadways.

Chemical Hazards

Be aware of potential chemical hazards you may encounter when returning to your home. Flood waters may have moved or buried hazardous chemical container of solvents or other industrial chemicals. Contact your local fire department about inspecting and removing hazardous chemical containers. Avoid inhaling chemical fumes.

If any propane tanks (whether 20-lb. tanks from a gas grill or household propane tanks) are discovered, do not attempt to move them yourself. These represent a very real danger of fire or explosion, and if any are found, the fire department, police, or your State Fire Marshal's office should be contacted immediately.

Car batteries, while flooded may still contain an electrical charge and should be removed with extreme caution by using insulated gloves. Avoid coming in contact with any acid that may have spilled from a damaged car battery.

Last reviewed on Jun 20, 2023 request edits
Mississippi State Department of Health 570 East Woodrow Wilson Dr Jackson, MS 39216 866‑HLTHY4U Contact and information

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