Health Risks of Flooding

Prepare an Evacuation Plan

The best way to minimize the health risks associated with flooding is to prepare an evacuation plan well in advance of a flood. 

This includes:

Prepackaging medications

• Making plans to relocate family members, farm animals and domestic pets
• Advising the Emergency Measures Organization of any disabled or bedridden family members who may need special assistance in an emergency
• Consulting with the Department of the Environment about dealing with hazardous products, such as pesticides. Special effort should also be made to make sure oil and gasoline tanks are secure.

Iroquois River [August 14, 2004]	Green River [August 14, 2004]

After a Flood

For personal protection during clean-up, wear rubber gloves and other protective clothing. Avoid direct skin contact with contaminated material. Practice good personal hygiene (i.e. wash hands before eating or smoking) and change outer clothing before entering a "clean" residence.

Water Contamination

Private water supplies affected by flooding should not be used until they have been disinfected. This can be done 10 days after water recedes by pouring 1 litre (one quart) of liquid bleach into the well. Taps should then be turned on until chlorine can be smelled from each tap, then turned off for 24 hours. Taps should be run again until the odor or taste of chlorine has disappeared. If possible, avoid discharging this chlorinated water into your septic tank. It is better, for example, to hook up a garden hose to a tap and discharge the water to a ditch. Water should be tested by a Public Health inspector before it is used for drinking. Until tests indicate a safe water supply, water for drinking and personal use should be brought to a rolling boil for at least 1 minute and then stored in clean covered containers.

Mould and Mildew

To avoid the health hazards of mildew and bacterial mould, water soaked walls and insulation should be removed, and the space and studding allowed to dry thoroughly. Walls constructed of gyproc, plaster or wood will dry out in time but insulation in these walls is no longer effective. As insulation becomes water soaked the weight causes it to settle and compact at the bottom, leaving a large portion of the wall no longer insulated.

Caution: 
Obtain approval from assessors, insurance agents and other relevant agencies before discarding or destroying any furniture or equipment.

Foods Affected by Flooding

To avoid the health hazards of food contamination, all perishable goods, vacuum-packed foods and any other foods affected by flooding should be thrown out. Commercially-canned food properly identified by labels, containers which show no leaks, swelling or rusting at joints or edges should be thoroughly washed and dried. Vacuum-packed foods pose a special hazard due to dried waste material inside crevices and covers. They should be discarded.

Home preserves, meats, fish or dairy products should be discarded as unsafe if they have been affected by flood water. Frozen foods left in a freezer will stay frozen for a few days without electricity if the door is kept shut. These products can be refrozen if ice crystals are still present and the food has not been exposed to flood waters. All perishable food left in a refrigerator more than 24 hours without electricity should be discarded.

Cooking and eating utensils should be cleaned of all deposits, washed with a household detergent or soap and rinsed for at least two full minutes in a mixture containing 15 millilitres (one table spoon) of liquid bleach in 4.5 litres (one gallon) of water. Utensils used for infant feeding should be boiled before use.

Refrigerators, Freezers, Stoves and Other Appliances

They should be cleaned in the following way:

• Ensure electrical power is turned off.
• Clean the unit thoroughly with a detergent solution, rinse with clean water that has been previously boiled, then wash with a solution containing one-half cup of Javex or similar product in nine litres (two gallons) of water.
• Allow to dry with door kept open.

Note: 
Any appliance that has been partially or wholly immersed in water will have wet insulation with no insulation value. It cannot be dried without removal. A qualified service technician should be contacted before the appliance is put into service. 

Hazardous Products

Household hazardous products, such as pesticides, can also cause problems. Contaminated items and surfaces should also be cleaned. Although small amounts of household hazardous products or agricultural products can be placed in plastic bags and discarded with domestic garbage, significant quantities should be handled differently, under the advice of the Department of the Environment.

Basements and Rooms

The most important element when cleaning basements and rooms is the use of good soap or detergent, "elbow grease" and lots of hot water.

Walls, solid floors and ceilings should be thoroughly scrubbed with a good detergent or soap and water, then mopped with a mixture of 120 millilitres (one-half cup) of liquid bleach in nine litres (two gallons) of water. Water and wastes can be removed by pumping, pails, shovels, etc.

Wastes should be buried at least 15 metres (50 feet) away from the source of any water supply. Lime may be used to cover wastes before covering with soil. This advice applies to all disposal of wastes in the following section. Oil or petroleum products are usually removed with Varsol or similar products.

After cleaning, open doors and windows to air thoroughly and help the drying process.

Oil Clean-Up

An oil spill which occurs in a house could create a contamination problem that can be difficult to correct. Peat moss can be used to remove floating oil. If only finished basement walls have been affected, the odor can be eliminated by removing and discarding the wall covering, studding, insulation and any other permeable material. Caution should be taken in using electrical equipment during cleaning since the fumes could ignite and cause an explosion. Dispersants should also be avoided in cases where oil tanks have been ruptured.

Household Furnishings

Solid wood or metal furniture can be cleaned with a household detergent solution, wiping clean and then wiping dry. Furniture should be left to dry outside before furniture polish may be applied where needed. Upholstered furniture and mattresses affected by flooding should not be used. 

• Public Alerts

• Floods – What to do before and after
• After a Flood:

[1] Protecting Yourself When Cleaning Your Home
[2] Water Contamination
[3] Mould and Mildew
[4] Foods Affected by Flooding
[5] Refrigerators, Freezers, Stoves and Other Appliances
[6] Hazardous Products
[7] Basements and Rooms
[8] Oil Clean-Up
[9] Household Furnishings

• N.B. Emergency Measures Organization
• Department Public Safety