When flooding of an area has occurred, either due to heavy rains or sewer back-ups, important steps must be taken to assure the health and safety of individuals involved. It must be assumed during cleanup operations that all surfaces have been contaminated with disease causing organisms.
Floodwaters are contaminated with pathogenic organisms from failing septic systems and from the flooding of municipal wastewater treatment and collection systems. Everything that comes into contact with floodwaters should be considered contaminated. This important assumption must be considered in decisions involving personal safety such as immunizations against disease as well as what items may be salvaged and what must be discarded.
The Hamilton County Health Department has developed information sheets to help individuals in flood recovery. Drinking water is a necessity of life and water wells submerged by flood water should be assumed contaminated until the well has been sanitized, using chlorination procedures and tested safe for consumption. Secondly, all food products should be discarded. Salvaging food products can only be done if the product container can withstand boiling water and sanitized in a bleach solution. Lastly, rehabilitation of household items will require great care and often-professional services.
Flood Safety Tips
Know your flood risk and elevation above flood stage. Do your local streams or rivers flood easily? If so, be prepared to move to a place of safety. Know your evacuation routes.
Keep your automobile fueled. During a power outage, gas stations may be unable to supply fuel.
Store drinking water in clean bathtubs and in other containers in case community water service is interrupted or your private water supply becomes contaminated.
Keep a store of food on hand that requires little cooking and no refrigeration.
Keep first aid supplies on hand.
Keep a NOAA Weather Radio, batteries, and flashlights in working order.
Proper hand washing must be considered the most important aspect of personal protection.
Cleanup personnel should wash their hands frequently during and after cleanup.
Boots and rubber gloves should be worn at all times. In cases where rigorous splashing of contaminated water may occur, a dust mask and eye protection should also be worn.
Open windows to provide adequate ventilation when using a bleach solution.
Cover all cuts and open wounds to prevent infection.
Do not eat, drink or smoke during cleanup.
Tetanus vaccines are available for free or for a small fee at all 94 local health departments in Indiana in the event of a disaster. Contact the Indiana State Department of Health or the Hamilton County Health Department for more information.
The potential for electric shock is a true possibility in any flooded area. Wear rubber boots in wet areas until it is certain no electrical hazards exist.
Turn off main switches and unplug electrical appliances in wet areas.
Do not turn on any appliances which have become wet until they have been thoroughly dried and checked for proper operation.
Do not use matches, torches or any other open flame until the area has been thoroughly vented to remove natural gas. The gas or liquid propane supply to all appliances in flooded areas should be shut off until the appliance has been checked
Bacteria, viruses and fungi must be killed in the cleanup process. The
most widely accepted, safe and effective sanitizing agent is
hypochlorite in the form of household bleach. The bleach solution
recommended for cleanup is 1 half cup of bleach to 1 gallon of water.
This solution will have sufficient strength to kill pathogenic
Time is an important consideration in cleanup. Pathogenic organisms will
not become airborne as long as the surfaces they have contaminated
remain wet. Thus, the only way these organisms can enter the body and
cause disease is through water splashing into the mouth, mucus
membranes, open cuts, etc. Once dried, organisms can be spread on dust
particles by air movement. Therefore, it is important to bring the
bleach solution into contact with the contaminated surfaces as soon as
possible after rinsing off heavy soil. Immediately following
disinfection, dry all surfaces to prevent rotting and decomposition.
Steps to Take Following Flood Water Recession
Assure that the above personal protection and general safety steps have been taken.
Determine what items will have to be discarded and remove them
for disposal. Generally, if the bleach solution comes into contact with
all of an items surfaces, that item may be salvageable. Stuffed
furniture, pillows and mattresses will have to be discarded,
indoor/outdoor carpeting and rugs may be salvageable. Thick wall to wall
carpeting and padding will have to be discarded or professionally
Thoroughly rinse all visible soil from all items to be kept.
Rinse the walls several inches above highest flood level. Carefully
rinse behind any base covering to remove all soil. Rinse down the entire
Prepare the bleach solution as directed above. It may be
possible to immerse smaller items in the solution. A broom or mop may be
used on larger surfaces to aid in applying the bleach and water.
If the flood waters have reached more than several inches up the
sides of hollow walls, these walls will have to be removed. Cut out the
area of drywall that has become wet and discard. Thoroughly saturate
the remaining studs with the bleach solution.
Allow the bleach solution to remain on all surfaces for at least 15 minutes for adequate kill time.
Several methods can be used to dry the cleanup area. Fans,
dehumidifiers, fresh air ventilation, mops, squeegees, and wet/dry
vacuums are all good alternatives.
Over the several weeks following the flood replace disposable
furnace filters or clean permanent filters with the bleach solution
several times to reduce trapped mold spores.