What to do during a flood?

Heavy rainfall and snow melt can cause high risk of flooding in residences in low lying areas or near bodies of water. Other factors can include:

• Drainage, soil type, and flood control systems, as well as, ice jams in rivers

Floods can:

• Disrupt essential services such as transportation, power, and water;
• Cause residential well contamination and strain wastewater services;
• Cause power outages; and/or
• Trap residents in their homes or vehicles.

In the event of a flood ensure that you:

• Move to higher ground if there is a chance of a flash flood;
• Listen for updates. If advised evacuate immediately!
• Shut off the electricity in your home at the circuit breakers;
• Have an emergency kit close by; and
• Monitor your surroundings.

See Government of Ontario for more information.

What are the health hazards after a flood?

Although anyone who has been flooded out of their home will be anxious to get back to ordinary life as soon as possible, it is important to remember that flood waters are usually contaminated and should be handled accordingly. During flood conditions, water leaves the normal course of stream beds and washes over the countryside. After contact with farmyards, manure piles, refuse heaps, outhouses and other sources of disease, flood waters become heavily contaminated and create potential health hazards.

When is it safe to return home?

Persons should not occupy flooded homes until cleanup has been completed and arrangements have been made for a supply of safe water and for satisfactory disposal of human wastes and garbage. If you are in any doubt about these issues, contact your local health unit office.

If your home is in an area served by a public water supply system, it is very probable that the water supply will be safe. If it is not, you will be notified locally. If your water supply comes from your own well, you must assume that the water is contaminated until bacteriological tests show the water to be safe. If the water in the well appears to be clear, it may be used following boiling or disinfection. (NOTE: Separate instructions for the disinfection of wells by chlorination are available.)

Cleaning of flooded homes

All movable furnishings should be taken outside. All woodwork should be thoroughly cleaned with soap and water. Upholstered furniture that has been in contact with water should be left outside to dry thoroughly (direct sunlight has a strong disinfecting power). The floors and surfaces in homes that have been flooded should be thoroughly cleaned and scrubbed as soon as possible after the water has receded. In most cases, common household cleaning products and disinfectants are used for this task. Read and follow label instructions carefully and provide fresh air by opening windows and doors. Be careful about mixing household cleaners and disinfectants together. Check label for cautions on this. Mixing certain types of products can produce toxic fumes and result in injury or even death.

When pumping basements, care must be taken not to pump the basement too quickly; water in the surrounding soil may cause the collapse of basement walls and/or uplifting of basement floors.

Once the water has left the basement, immediately remove all the accumulated silt and mud. This may require the use of a hose, buckets of water, and rough scrubbing. Remove all portable effects (such as stored furniture, etc.). Encourage drying by opening all windows; if the electricity and/or natural gas have been reconnected and inspected, apply heat via a furnace or stove. All surfaces that have been exposed to flood waters should be disinfected by brushing on a chlorine solution as described above.

Canned foods

Canned goods should be closely checked for leaks and swells. Particular attention should be paid to seams and joints for signs of erosion. Home preserved fruits in jars and sealers which show evidence of contamination around the tops should be discarded. Although many of these jars may be safe, there is a danger which may manifest from gross physical changes in the contents. Any canned goods or preserves directly in contact with flood waters should be discarded.

Perishable foods

Perishable foods including all kinds of meats and dairy products should be discarded, if there is evidence of contact with flood water. Perishable foods thawed or unrefrigerated for a period of two hours or longer should be discarded.

Wrapped foods

Foods which have been wrapped in moisture-proof wrappers should be examined for breaks in the wrapper. Intact wrappers should be removed and the product re-wrapped. Where there is evidence that the wrapper has been pervious to moisture, the product should be regarded as unsafe.

Food handling equipment should be thoroughly scoured and washed and then treated with an effective disinfecting solution. Chlorine not less than 100 parts per million and preferably up to 400 parts per million (one to four tablespoons of household bleach per gallon of water /15 ml to 60 ml per 4 L) are satisfactory, or emersion in boiling water for at least one minute. In all cases, a generous safety margin should be allowed.

Drugs and medicines

Drugs and medicines that have been in contact with flood water should be destroyed. No attempt should be made to replace loosened labels as this is dangerous. All unlabeled drugs should be destroyed. Do not leave them where they may be found by children.

Electrical hazards

No attempt should be made to try out or to operate any electrical appliances until the wiring in your home or buildings has been inspected and found safe.

Heating Hazards

Three main hazards exist from domestic or other heating systems following flood damage. These hazards are explosion, suffocation and fire. Householders are therefore warned to take every precaution to see that the heating system is safe before resuming its use.

The cleaning of various outbuildings

Cleanup and disinfecting procedures should extend to all sheds, garages and other buildings where goods are stored. In particular, utensils used for the preparation, preservation or storage of food should be thoroughly washed.

Outhouses, septic tanks and disposal fields

High water will have flooded outhouse pits, making a potentially dangerous source of contamination to local water supplies. If the outhouse building remains in place, it may be used as soon as the water has left the surface of the ground. But in order to eliminate the risk of contaminating the water table, it is advisable to empty the contents of one pound (500 g) of fresh chloride of lime into the pit every three or four days for as long as water remains in the pit. If the outhouse building has been washed away, a new one should be built as soon as possible. Open outhouse pits should be covered to prevent accidents.

In most instances, flooding will not seriously affect septic tanks. It may, however, cause damage to the sewage disposal field if the system is used before flood waters recede below the distribution trenches. It is wise to obtain the opinion from your local health unit before subjecting your flooded sewage disposal field to additional liquid loadings, particularly where the earth has clay deposits or is known to be a ‘tight’ soil.

General cleanup

Following the cleanup of buildings, attention must be turned to the removal of flood-borne material from yards. All refuse should be collected into conveniently located heaps for removal by the local garbage pickup, if one is available. Particular effort should be made to remove all filth that might, in warm weather, serve as a breading place for flies and rodents.

See Government of Canada for more information.