Residential Flooding

 Read the City of Ottawa's latest update on seasonal flooding 

Flooding 2019- Well water samples: Water bottle pick up and water sample drop off locations.

NOTE: Before you test your well, remember to read our Safe drinking water - Private well owners information in the After a flood - Recovery section

Well water testing - pick up and drop off locations - Residents wishing to pick up water bottles and drop off their samples may do so at established permanent sites across Ottawa.


There are several ways floodwater can enter your home and pose health or safety risks. The following information on flood prevention, staying safe during a flood, and recovery after a flood will be useful to Ottawa residents in the event water enters homes from a leaky roof or basement, overland flooding such as a river overflow during the spring freshet, or from a leak from a pipe within your building. Being prepared and having a plan will help residents deal with the stress and disruption that go along with flooding events.

Flooding prevention - Plan, Prepare, Be Aware

Prevent flooding

Floods can pose different levels of risk depending on the source of the water, the volume of water and how quickly and easily the floodwater can be removed. The City of Ottawa has useful information on their Flood Information website on the following topics:

Be prepared for an emergency

It is important to be prepared for emergencies. To be ready, have a kit with supplies that make you and your family self-sufficient in your home for 72 hours. The City of Ottawa has a Safety and Emergency Preparedness website with information on:

  • How to make your own emergency preparedness kit so you can be self-sufficient for at least 72 hours.
  • A special needs checklist to help ensure everyone's unique needs are provided for during an emergency.

Minimize the impact of flooding

If flooding or sewage back-up in a basement is a high risk or imminent , remove valuables to higher levels while you still have time to do this.

The City and Conservation Authorities work to reduce flood risk

The City and Conservation Authorities take preventive steps to protect homes from the spring snowmelt or freshet.  This includes blasting ice on some sections of the Rideau River that are at risk of overland flooding before the freshet, clearing storm water drains, and providing an interactive map of areas at risk of overland flooding to residents.

Safe drinking water - Private well owners 

Well water can contain harmful bacteria that causes stomach cramps, diarrhea and other health concerns. Private well owners are encouraged to get their water tested every spring, summer and fall, even if it looks, tastes and smells fine. 

Whether your test results are positive or negative, understand that the sample you collected is just a "snapshot" of your well's water quality. The more samples you have tested, the more confident you can be about the quality of the water you are drinking.

In addition to regularly testing well water, owners should inspect their well at least once a year to make sure it is free from damage and in good working condition.

Learn more about free private well water testing.

During a flood - Keep you and your family safe

There are several ways floodwater can enter your home and pose health or safety risks. The following information on staying safe during a flood will be useful to Ottawa residents in the event unwanted water enters your home.  Protecting yourself during a flood and restoring your home after a flood can be a very stressful time. Ottawa Public Health suggests the following information to help you protect yourself and your family from illnesses associated with contaminated floodwaters.

Stay safe

During the spring thaw, rivers, streams and lakes swell with snowmelt and rainwater, making them very dangerous for people and pets. There is an increased risk of drowning and injury because of high water level, faster flow, cold temperature and debris in and below the water surface.

  • Do not wait to evacuate. Move to higher ground as soon as you can.
  • Stay away from edges of waterways, as the banks can be slippery.
  • Do not walk or drive through floodwater even if it looks like it is shallow. 
  • Keep children away from floodwater. 
  • Stay within sight and arm’s reach of children when outdoors near water
  • Keep pets on a leash. Do not try to rescue pets who are in cold water. 

Be aware that there are many risks in and around flooded areas and that you will need to take precautions in order to protect your health.

Prevent Infections and Illnesses 

Harmful bacteria, viruses or other microorganisms may be present in floodwater, even if they do not involve sewage backups. In some circumstances, chemical hazards may also be a concern.  Always consider floodwater and surfaces that have been in contact with floodwater to be contaminated.  Wear personal protective clothing and equipment when working in floodwaters.  This may include rubber boots and waterproof gloves.  Hand washing / hand-hygiene is important even if you have worn gloves – always wash your hands after removing your gloves and before eating or drinking. Depending on the work you are doing, e.g., using power equipment, additional personal safety equipment may be required (see After a Flood-Recovery - Wear protective clothing and equipment).   

  • If you cut or puncture your skin, clean and disinfect the wound as soon as possible and then protect it by keeping it dry and clean. Seek medical attention if you have not had a tetanus shot in the past 10 years or if signs or symptoms of infection, such as redness, swelling or oozing develop.
  • If you rely on a private well for drinking water, do not drink the water until you have determined if your well has been affected by floodwater and you have tested it for bacteriological safety. Use boiled or bottled water. Testing your well water should occur after the floodwaters have receded. 
  • Toilets and septic systems are often impacted by floodwater. Only flush your toilets and drain water from your sinks if your septic system is not submerged in floodwater in order to prevent sewage backing up into your home. 
  • Always wash your hands with soap and clean water or use an alcohol-based hand rub before preparing or eating food, after toilet use, after contact with floodwater, and after handling articles contaminated with floodwater. For more information on handwashing visit Ottawa Public Health Handwashing web page.
  • If soap and water are not available, and hands are not visibly soiled, use an alcohol-based hand rub (ABHR) that contains at least 60% alcohol. If hands are visibly soiled and running water is not immediately available: 

    • Remove visible soil using moistened towelettes
    • Once the visible soil is removed, clean hands with alcohol based hand rub (ABHR) containing at least 60% alcohol
    • Wash hands with soap and water as soon as it becomes available
Safe drinking water - private well owners

If flood waters have reached the level of your well head, or covered your well head, your well water may be contaminated and not safe to drink.

Residents who own private wells affected by flooding are advised to:

  • The best option is to stop using your well water and use another potable water source such as bottled water for ALL water use, including drinking, preparing food, cleaning, bathing, hand washing.
  • If you want to continue to use your well water and do not suspect chemical contamination, bring the water to a rolling boil for at least one minute and let it cool before using it for drinking, making infant formula, juices, ice or recipes, brushing your teeth, rinsing contact lenses, and washing food or dishes. Refrigerate your boiled water until it is used. 
    • If you suspect chemical contamination of your drinking water and well, please contact the Ontario Ministry of Environment, Conservation and Parks (MECP) well help desk at 613-521-3450.
  • Do not test your well water during a flood.

Sewer backups and basement flooding

While the City regularly cleans, inspects and repairs the sanitary and storm sewer systems, unanticipated problems can occasionally occur, causing increased water levels in the sewer (or surcharging).

Learn more about sewer backups and basement flooding.

Septic systems

  • Do not use the septic system (i.e. no flushing toilets or draining water from sinks, bathtubs, showers or dishwashers) until the water around the house is lower than the septic drainage field and enough time has been given for the soil to adequately drain. The soil requires additional time to drain in order to allow sewage to be absorbed. This may take several weeks after flood waters recede depending on the length of time the system was under water and the soil conditions.
  • Do not pump out your septic tank while the soil is still wet or under water. This could cause damage to the tank, the inlet/outlet pipes or it could cause the septic tank to float out of the ground.
  • Your septic system may need to be inspected by a certified private sewage installer before restarting. The inspection of your septic system should take place after floodwater has receded.

Flooding Related Questions Applicable to All Types of Septic Systems

What steps should I take if my septic system is flooded?
  • It is strongly recommended that the system should not be used while the septic drain field or tanks are covered with water. The sewage system should not be used until the water in the septic drain field is below the distribution pipes.
  • If the system must be used, conserve water as much as possible while the system attempts to restore itself as the ground water table falls.
  • Flood water may be contaminated with sewage. Protect yourself by wearing protective equipment such as gloves, protective eyewear, a face mask and rubber boots. Be sure to wash your hands frequently with soap and water.
  • Do not pump your septic tank. Pumping out a septic tank that is sitting in saturated soil may cause it to “pop out” of the ground. Newer systems are more likely to pop out than older systems because the soil may not have completely settled and compacted around the septic tank.
  • Try to avoid using any heavy machinery near the septic drain field or tanks in a saturated state, as they are especially vulnerable to damage under flooded conditions.
  • If sewage has backed up into a basement, clean the area and disinfect the floor. Use a chlorine solution of a half cup of chlorine bleach to a gallon of water when mopping the floor.
  • If you have a ground water well, do not drink the water until water testing proves it to be safe for consumption.

What steps should I take if I have a pumped system?

  • Do not operate the pump until floodwaters have receded and the groundwater table is below the pump chamber bottom/floor. Operating the pump to empty the chamber during high water events may cause the pump chamber to “pop out” of the ground due to buoyancy forces.
  • Avoid contact with any electric pump or equipment that may have been submerged during the flood. Have a licensed electrician inspect all electrical equipment before they are returned to normal operation.

What steps should I take if I have an Advanced Treatment Unit (for example: Ecoflo, Waterloo Biofilter, Puraflo, etc.)?

  • If you have an Advanced Treatment Unit, the system should not be used until the maintenance provider or licensed septic installer has verified proper system operation.
  • Do not pump treatment tanks until floodwaters have receded and the groundwater table is below the bottom/floor of the treatment tank. Pumping the tank during high water events may cause the pump chamber to “pop out” of the ground due to buoyancy forces. 
What should I do if I’m having septic problems after the floodwaters recede?
  • Do not pump out your septic tank until water levels recede below the bottom/floor of the tank. At best, pumping the tank is only a temporary solution. Under worst conditions, pumping it out could cause the tank to “pop out” of the ground due to buoyancy forces and may damage the inlet and outlet pipes.
  • Have your septic tank professionally inspected by a licensed septic installer or licensed sewage hauler if you suspect damage. Signs of damage include visible settling of the ground above the tank or an inability of the system to accept additional water. Most septic systems are not damaged by flooding since they are below ground and completely covered. However, septic tanks and pump chambers can fill with silt and soil and must then be cleaned. If the soil absorption field is clogged with silt, a new system may have to be installed as the there is no effective way to clean out the buried lines in an absorption field.
  • Have your tanks cleaned and/or repaired by a licensed septic installer or licensed sewage hauler as the tanks may contain dangerous gases and pathogens.

What should I do with my outhouse?

  • Ensure that the outhouse is still positioned over the pit. If the outhouse has been washed away, or collapsed, cover the open pit with sturdy boards to prevent accidents and the spread of disease. If water is in the pit, add two litres (two quarts) of unscented liquid chlorine bleach every three to four days until the water disappears.

When do you contact the Ottawa Septic System Office or other Septic Regulator?

  • You must contact the Ottawa Septic System Office or your local septic system Approval Agency for any repair or replacement of your sewage system. No permit is required for replacing electrical components such as pumps, control panels, etc.

Source: The Rideau Valley Conservation Authority

For more information on septic systems, visit The Rideau Valley Conservation Authority website (English only)

Safe food donations
Food donations can be helpful to those impacted by a flood. Visit Ottawa Public Health's Food Safety web page for guidelines on how to donate food safely.

Prevent Injury and Loss of Life

Be aware of the following physical hazards during and after a flood:

Drowning 

Standing and flowing waters present drowning risks associated with driving, walking or swimming through floodwater. During overland flooding, such as a river overflowing, it is important to leave a flood risk area before waters rise to prevent being trapped and risking drowning. If flooding is related to a rainfall event or plumbing issue, ensure people entering the area take precautions against drowning risks such as never enter a flooded area alone and wear a floatation device.

Electrocution

Electrocution is a safety risk when entering flood-damaged areas. Do not enter your basement, or other impacted areas of your home, if you know or suspect water has risen above the level of electrical outlets, baseboard heaters, and furnace, or is near your electrical panel. If you are unsure, have a licensed electrician check it out before you enter any areas with pooled water. Do not turn on any electrical appliance (major or small, furnace, water heater, etc.) if it has gotten wet. Have it checked by a qualified service technician to confirm it is safe to do so. 

Power outages and risk of carbon monoxide poisoning 

Do not use the following  indoors or in garages during a power outage:

  • charcoal or gas barbecues,
  • camping heating equipment
  • home generators
  • gasoline/diesel equipment (pumps, fans)

The use of these alternative sources can cause carbon monoxide (CO) to build up in your home. Make sure there is at least one working carbon monoxide detector installed at or near floor level.

Safety for children and people with disabilities

Ensure children are adequately supervised and keep them away from floodwater. Ensure people with disabilities are aware of the risks of floodwater and they have assistance getting to a safe and supervised place.  When outdoors, always keep children within arm’s reach in and around water.

Slippery surfaces, poor lighting, heavy objects and exhaustion

Surfaces will be slippery and falls with injuries are likely.  Poor lighting may increase risks of injury, especially if there are power outages or it is unsafe to turn on lights.   Working when overtired can result in injuries. It is important to set a realistic schedule and take frequent rest and nutrition breaks.  Objects are heavier when wet. 

Hypothermia

Being exposed to cold water can increase the risk of hypothermia.  Wear waterproof outerwear, a warm layer of clothing and an inner layer of clothing that wicks moisture away from your body.  Be aware of the early signs of hypothermia (drowsiness, weakness and loss of coordination, confusion, shivering, and pale and cold skin).  

Be safe around energy sources

Flooding can affect the safety precautions you may need to take around your power source.  All power sources (i.e. electrical, oil, natural gas and propane) will have risks that may need to be addressed during and after a flood.  Please contact your energy provider for information specific to your energy source for more information. 

 

After a flood - Recovery

Prevent Injury and Illness when cleaning up

Once it is safe to return to your home, be sure to take precautions to protect you and your families’ health and safety. Floods may involve cleanup efforts that are costly and require the involvement of professional expertise and equipment (e.g. generators, water pumps, drying fans and cleaning solutions).

Water damaged materials and contents need to be assessed, sorted, cleaned and dried as soon as possible to prevent the growth of mould and further damage to your home and impacts on your health.

OPH reminds that sandbags are just one of many things, objects, surfaces to have been affected by floodwaters and that persons should wash their hands carefully with soap and water (if unavailable use alcohol based hand rub) before preparing food, eating, drinking, or otherwise bringing hands to face.

OPH advises residents to avoid moving large heavy objects by themselves; these objects are heavier than normal when wet and may result in back or other injuries.

Safe food handling
After a flood, there are foods that need to be discarded and other food that you can keep as long as you disinfect them.
  • Discard all food items that have been exposed to flood water including food and beverage containers with screw caps, snap lids, crimped caps (soda bottles), twist caps, flip tops, corks, and home canned foods. These containers cannot be disinfected.
  • The only safe flood-exposed foods are those that are sealed in metal cans and that have not been damaged. Thoroughly clean and disinfect with bleach and water all undamaged cans before opening. Follow the chart below.
  • Wear waterproof gloves and wash hands with soap and clean water after removing gloves.
  • Ensure good ventilation when handling full-strength bleach and guard against splashing.
  • Learn more about food safety during a power failure.
   Recommendations for Cleaning and Sanitizing Food Cans and Surfaces
    Amount of bleach and water to mix  
Area or item to be cleaned Bleach amount Water amount Cleaning steps

Food surfaces that may have touched flood water.
Examples: Countertops, plates.
Note: Throw away wooden cutting boards, baby bottle nipples, and pacifiers.

1 cup (240 mL) 5 gallons (18.9L)
  1. Wash with soap and hot, clean water.
  2. Rinse with clean water.
  3. Sanitize in a solution of 1 cup (240 milliliters) of household chlorine bleach in 5 gallons (18.9 L) of clean water.
  4. Allow to air dry.

Food cans that are not bulging, open, or damaged

 1 cup
(240 mL)
 5 gallons (18.9 L)
  1. Remove can labels.
  2. Wash cans with soap and warm, clean water.
  3. Dip cans in mixture of 1cup (240 milliliters) of household chlorine bleach in 5 gallons (18.9 L) of clean water.
  4. Allow to air dry.
  5. Re-label cans with a permanent marker
Safe drinking water - Private well owners

After a flood – Private Well Water Information

For Homeowners Impacted by the 2019 Ottawa River Flooding

Summary

Follow the steps below and note that before testing your well water you should:

  1. Wait until the floodwaters have receded.
    There should be no floodwater immediately surrounding the well. The ground around the well may have eroded during flooding, possibly creating unsafe conditions or a pathway for surface water and contaminants to enter the well. In other cases, the electrical wires attached to the pump in a well may be damaged risking electrocution. Therefore, well owners should exercise extreme caution approaching their wells, especially older, large diameter dug wells after a flood.
  2. Disinfect your well with a chlorine solution and flush out this disinfectant.
                                                                    See Appendix A for information on “How to disinfect a well”. 
  3. Wait two days before collecting a water sample.  If your septic system is ready to use, and if you do not suspect chemical contamination of your well, you can use your well water for household tasks, but not for anything in which the water would be swallowed or get into the eyes or mouth.
    The best option is to stop using your well water and use another potable water source such as bottled water for ALL water use, including drinking, preparing food, cleaning, bathing, hand washing. If you want to continue to use your well water and do not suspect chemical contamination, bring the water to a rolling boil for at least one minute and let it cool before using it for drinking, making infant formula, juices, ice or recipes, brushing your teeth, rinsing contact lenses, and washing food or dishes. Refrigerate your boiled water until it is used. See the information further below on “What to do if your well is contaminated”.
  4. Take a sample of your well water.  If the result indicates your water is “safe to drink”, you will still need to take two additional water samples. 
    • The safest option is to continue using an alternative source of treated water or boiling your water as in step #3 above until you take a second sample and get a second “safe to drink” result.
    • The second sample should be taken approximately one week after the first sample. The water can now be considered safe to drink, but a third sample should be taken to be sure the well water remains safe.
    • The third sample should be taken 2 to 4 weeks after the first sample.  This will confirm the potability of your well water. 
    • If all three samples are safe, continue to sample three to four times per year

Water Sampling checklist - [PDF - 165 KB]

See below for information on “How to sample your well water for bacteria”.

Details

When to test well water and drinking water safety considerations

If floodwaters have reached the level of your wellhead, or covered your wellhead, your well water may be contaminated and not safe to drink. Residents who own private wells affected by flooding are advised to:

  • The best option is to stop using your well water and use another potable water source such as bottled water for ALL water use, including drinking, preparing food, cleaning, bathing, hand washing.
  • If you want to continue to use your well water and do not suspect chemical contamination, bring the water to a rolling boil for at least one minute and let it cool before using it for drinking, making infant formula, juices, ice or recipes, brushing your teeth, rinsing contact lenses, and washing food or dishes. Refrigerate your boiled water until it is used. 
  • If you suspect chemical contamination of your well, please note that Public Health Ontario (PHO) Laboratories test for the indicators of bacterial contamination (coliforms and E. coli); however, the sample is not tested for any other contaminants, including chemical contaminants. Click here for a list of licensed labs that can test your private well water for chemicals. If you suspect chemical contamination of your drinking water and well, please contact the Ontario Ministry of Environment, Conservation and Parks (MECP) well help desk at 613-521-3450. 
  • Do not test your well water during a flood.  Test your well water once the flood water levels have receded and the well is no longer affected by floodwater. There should be no floodwater immediately surrounding the well.
  • The ground around the well may have eroded during flooding, possibly creating unsafe conditions or a pathway for surface water and contaminants to enter the well. In other cases, the electrical wires attached to the pump in a well may be damaged risking electrocution. Therefore, well owners should exercise extreme caution approaching their wells; especially older, large diameter dug wells after a flood.
  • Before testing your well water, it is important to first disinfect your well with a chlorine solution and flush out this disinfectant.
  • Wait two days before collecting a water sample.  Continue to use your water for household tasks, with the exception of drinking and cooking purposes.
  • Take a sample of your well water.  If the result indicates your water is “safe to drink”, you will still need to take two additional water samples. 
    • The safest option is to continue using an alternative source of treated water or boiling your water as in step #3 above until you take a second sample and get a second “safe to drink” result.
    • The second sample should be taken approximately one week after the first sample. The water can now be considered safe to drink, but a third sample should be taken to be sure the well water remains safe. 
    • The third sample should be taken 2 to 4 weeks after the first sample.  This will confirm the potability of your well water. 
    • If all three samples are safe, continue to sample three to four times per year. 
How to sample your well water for bacteria

Bacterial testing for private wells is performed free of charge by the Ontario Ministry of Health Public Health Laboratory at 2380 St. Laurent Blvd. Sample bottles are available for pickup at that laboratory, and at water testing pickup and drop-off locations.

  1. Obtain a water sample bottle.
  2. ​Plan to sample your well water when you are sure it can be delivered to a drop-off location within 12 hours of the collection time.
  3. Remove any aerator, screen, or other attachment from your kitchen faucet. If you cannot do this, take a sample from an inside faucet with no aerator, such as the bathtub. Do not take a sample from an outside faucet or the garden hose.
  4. Turn on the cold water and run for two to three minutes to remove standing water.
  5. Disinfect the end of the faucet spout with an alcohol swab, or a diluted bleach solution (1 part household bleach to 10 parts water).
  6. Turn on the cold water again and run for three minutes before sampling. Remove the lid of the sample bottle. Do not touch the inside of the lid, put down the lid, or rinse out the bottle. 
  7. Fill the bottle to "fill line" directly from the tap without changing the flow of water. Do not touch the bottle lip. Replace cap tightly.
  8. Samples must be refrigerated after collection. During transportation, put bottle in a cooler if possible.
  9. Remove ONE of the bar code stickers from the bottle and attach it to the blue card that came with your water sample bottle. This bar code is your PERSONAL IDENTIFICATION NUMBER (PIN).  You will need it to get your results over the phone.

10. Return the sample and completed form within 12 hours of collection.  If your form is incomplete, the laboratory will not test your sample and you will need to submit another sample with another form. 

Well water test results
You can usually get your test results three  to five business days after you drop off your sample.

Test results are available by:

  • Telephone: Call 1-877-723-3426 and key in the barcode number from the sample bottle (PIN) to hear an automated message with your test results and interpretation. OR
  • Mail: If you indicated on the form that you want the report mailed or made no choice, the report will be mailed to the name and address written on the form. OR
  • In-person at 2380 St. Laurent Blvd: ​If you indicated on the form that you will pick up the report at the laboratory, show your photo identification at the reception desk during regular operating hours. 

What the water test results mean

If you need help interpreting the results, please contact Ottawa Public Health at 613-580-6744 and speak with a Public Health Inspector.

Bacteriology interpretation

Drinking water is tested for the presence of two groups of bacteria: Total Coliforms and E.coli (Escherichia coli).

Total Coliforms are a group of bacteria commonly found in animal waste, sewage, soil and vegetation. They are also found in the intestines of animals and humans.  Total Coliforms are not likely to cause illness, but their presence indicates that your water supply may have been contaminated by more harmful microorganisms present in surface water seeping into your well.  

E.Coli bacteria are normally found only in human and animal digestive systems. The presence of these bacteria in your drinking water, usually means that human and animal waste is entering your well from a nearby source such as a local septic system or manure.  Although most strains of E. coli bacteria are harmless, the presence of E. coli in well water indicates fecal contamination.  This means there could be harmful bacteria, viruses, or parasites in your well water.

Intrepreting the results

Results

What it means?

What to do?

Total coliform=0 
E. coli = 0

No significant bacterial contamination was found

  • Continue to test your drinking water on a regular basis to see if there are any changes in your drinking water quality. 
  • Three samples taken 1-3 weeks apart are needed to determine the stability of the water supply.

Total coliform= less than or equal to 5
E. coli = 0

No significant bacterial contamination was found

  • Safety difficult to assess based on a single test. 
  • Resample as soon as possible.
  • Follow the Public Health Ontario water sampling procedures above.Three samples taken 1-3 weeks apart are needed to determine the stability of the water supply.

Total coliform= more than 5
E. coli = 0

Significant bacterial contamination was found

Stop using your well water, use bottled or boiled water.

  • If you want to continue to use your well water, bring it to a rolling boil for at least one minute and let it cool before using it for drinking, making infant formula, juices, ice or recipes, brushing your teeth, rinsing contact lenses, and washing food or dishes. Refrigerate your boiled water until it is used.
  • Disinfect the well and resample, following the proper disinfection procedures below.

Total coliform= 1 or more
E. coli = 1 or more

Indicates bacterial contamination from animal or human feces

Stop using your well water, use bottled or boiled water.

  • If you want to continue to use your well water, bring it to a rolling boil for at least one minute and let it cool before using it for drinking, making infant formula, juices, ice or recipes, brushing your teeth, rinsing contact lenses, and washing food or dishes. Refrigerate your boiled water until it is used.
  • Disinfect the well and resample. Follow proper disinfection procedures described below.

NDOGN - No Data: Overgrown with Non-target

Only "non-target" bacteria commonly found in the environment are visible during the test process. They are not usually a health hazard but can interfere with detection of Total Coliforms and/or E. coli 

Stop using your well water, use bottled or boiled water.

  • If you want to continue to use your well water, bring it to a rolling boil for at least one minute and let it cool before using it for drinking, making infant formula, juices, ice or recipes, brushing your teeth, rinsing contact lenses, and washing food or dishes. Refrigerate your boiled water until it is used.
  • Disinfect the well and resample. Follow proper disinfection procedures described below.

NDOGT - No Data: Overgrown with Target

A large number of bacteria present and Total Coliforms and/or E. coli are visible to the analyst but it is dificult to determine exactly how much

Stop using your well water, use bottled or boiled water.

  • If you want to continue to use your well water, bring it to a rolling boil for at least one minute and let it cool before using it for drinking, making infant formula, juices, ice or recipes, brushing your teeth, rinsing contact lenses, and washing food or dishes. Refrigerate your boiled water until it is used.
  • Disinfect the well and resample. Follow proper disinfection procedures below.

What to do if your well is contaminated

If you want to continue to use your well water and do not suspect chemical contamination, bring it to a rolling boil for at least one minute and let it cool before using.

 

Use tap water for:

Use bottled or boiled water for:

Do not use the water for:

  • Flushing toilets
  • Washing clothes, linens and bedding
  • Taking showers (for adults and older children)
  • Washing floors
  • Drinking
  • Brushing teeth
  • Making food and baby formula
  • Sponge bathing babies and young children (after cooling the water)
  • Making coffee
  • Making ice
  • Washing fruits and vegetables
  • Kitchen and other household water filters
  • Ice makers directly connected to the affected water supply
  • Children's water play stations (e.g. wading pools and water tables)

Appendix A: How to disinfect a well

To bring a well back into service safely, a well owner should consider contacting:

  • a qualified registered professional (e.g. professional engineer or professional geoscientist) or a licensed well driller to evaluate and service a drilled well;
  • a qualified registered professional or a licensed well digger to evaluate and service a dug well;
  • a licensed pump installer and, if necessary a certified electrician, to evaluate and service the well pump. 
  • To find a liscenced contractor, refer to the Ontario Ministry of Environment, Conservation and Parcs website.

A residential private well owner can work on and disinfect his or her own well.  However, there are some safety considerations when working on a well and many technical steps needed to properly clean and disinfect a well.  Therefore, the well owner should consider retaining the services of a qualified professional or qualified technician as noted above. 

See special considerations for Sand point wells, dug wells and drilled wells below.

You can disinfect your well contaminated with bacteria by "shock-treating" it with ordinary chlorinated household bleach containing 5.25 per cent sodium hypochlorite. Don't use scented bleach for this purpose. Buy fresh bleach to do this because the chlorine in bleach is unstable and evaporates over time. 

  1. Store enough clean water to meet household needs for a minimum of 12 hours.
  2. Bypass or disconnect any carbon filters, water softeners or other water treatment devices or else any pipes located past these filters will not be disinfected. Replace the filters once chlorination is completed. Highly chlorinated water can damage treatment units. The treatment devices will themselves have to be disinfected: It is important to follow the manufacturer’s recommendations to ensure any treatment systems are properly disinfected. Be sure that the hot water tank’s heat source is shut off.
  3. Estimate the chlorine necessary to disinfect the water in the building’s plumbing including the hot water tank, and the chlorine necessary to disinfect the water in the well water column.  Add them together.
  4. Drain all water out of plumbing including the hot water tank prior to dosing.
  5. Mix the chlorine required to disinfect the well in 25 litres (5 gallons) of water.
  6. Pour the mixture into your well.
  7. Thoroughly mix the chlorine solution and the water throughout the well column. This can be accomplished by attaching a hose to a tap and running water from the well through the hose and back into the well.
  8. Start the pump and bleed air from the pressure tank. Open all water taps one at a time, including outside hose bibs and cold and hot water taps. Allow the water to run until a chlorine smell is detected from each faucet then turn off each tap. Since chlorinated water can damage the action in a septic system, chlorinated water should not be allowed into the building’s sewage system.
  9. If a strong chlorine odour is not present, return to step 4, add half the amount of chlorine used for the initial treatment to the well and repeat steps 5 and 6.
  10. Let the chlorinated water stand in the system for 12 to 24 hours.
  11. Start the pump and run water through the outside hose away from vegetation until the strong smell of chlorine disappears. Make certain that the water does not enter any watercourse.  Finally, open the indoor taps until the system is completely flushed. Taps or fixtures discharging to the septic tank systems should be temporarily diverted to an outside discharge point to avoid affecting the septic system.
  12. Wait 48 hours and then sample the water using the instructions and bottle provided by the laboratory. If the result indicates your water is “safe to drink” you will still need to take two additional water samples.  The second sample should be taken approximately one week after the first sample.  The third sample should be taken 2 to 4 weeks after the first sample.  This will confirm the potability of your well water.  If all three samples are safe, continue to sample three to four times per year.
  13. If the above steps do not alleviate the problem, it is recommended that the source of the ongoing contamination be determined and corrected, possibly with professional help.

Resample your drinking water after corrective actions have been taken. As a private well owner, you are ultimately responsible for the system maintenance, operation and quality of your water. If your drinking water quality does not improve, you may need to have your well inspected by a licensed well contractor who will be able to provide you with options to address the issue.

You could also install a treatment system to remove bacteria. For treatment options, consult with a water treatment professional.

Disinfecting a Sand Point Well (Well Point)

A well with a diameter of two inches (5 cm): Add about one quarter ounce (6 ml) of household bleach for every 10 ft (3 m) of water depth.

Before starting the disinfection process, the outside of the sand point well (well point) and all associated equipment should be cleaned and disinfected. Homeowners can use disinfectant wipes or alcohol swabs. Unscented household bleach can be introduced in the well by removing the well cap. Ensure your pump does not run dry.

Using a drain plug opening, pressure gage opening outlet pipe, or other opening into the pressure tank, add chlorine bleach or other chlorine into the pressure tank, so that the water in the tank contains approximately 50 ppm free chlorine. This will take approximately 3 (three) tablespoons, or 1 ½ ounces of bleach for each 10 (ten) gallon of tank capacity (a 50-gallon tank, for example, will require approximately ¾ (three quarters) of a cup of bleach).

Disinfecting a Dug Well

A well with a diameter of three feet (1 m): Add one quart (one litre) of household bleach for every five feet (1.5 m) of water depth.

Well Depth (feet)

Well Depth (metres)

Bleach Volume (litres)

5

1.5

1

10

3

2

Disinfecting a Drilled Well

A well with a diameter of six inches (15 cm): Add five ounces (148 mL) of household bleach for every 25 ft (7.6 m) of water depth.

Well Depth (feet)

Well Depth (metres)

Bleach Volume (fluid oz.)

Bleach Volume (ml)

25

7.5

5

148

After a flood – Private Well Water Information For Homeowners Impacted by the 2019 Ottawa River Flooding Well [PDF - 210]

Sewer backups and basement flooding

While the City regularly cleans, inspects and repairs the sanitary and storm sewer systems, unanticipated problems can occasionally occur, causing increased water levels in the sewer (or surcharging).

Learn more about sewer backups and basement flooding.

Septic systems

The following recommendations are applicable to homes where septic systems are covered with floodwaters.

  • Do not use the septic system (e.g., no flushing toilets or draining water from sinks, bathtubs, showers or dishwashers) until the water level around the house is lower than the in the septic drainage field and enough time has been given for the soil to adequately drain. The soil requires additional time to drain in order to allow sewage to be absorbed. This may take several weeks after flood waters recede depending on the length of time the system was under water and the soil conditions.
  • Your septic system may need to be inspected by a certified private sewage installer before restarting. The inspection of your septic system should take place after floodwater has receded.
  • Do not drive vehicles and equipment over the septic system during cleanup or restoration activities. Do not set dumpsters or building materials over the septic system. Fence or mark out the system to protect it while restoration activities take place. Soil is easily compacted or displaced when wet. If the soil is compacted or displaced in the area of the septic system it may require extensive repairs.
  • Do not pump out your septic tank while the soil is still wet or under water. The septic tank could shift or float out of the ground, which could cause damage to the tank or the inlet/outlet pipes.
  • Be aware that the fill soil around the septic tank may be wet and cause concrete tanks to float even though the soil further away from the tank may not appear wet.

Flooding Related Questions Applicable to All Types of Septic Systems

What steps should I take if my septic system is flooded?
  • It is strongly recommended that the system should not be used while the septic drain field or tanks are covered with water. The sewage system should not be used until the water in the septic drain field is below the distribution pipes.
  • If the system must be used, conserve water as much as possible while the system attempts to restore itself as the ground water table falls.
  • Flood water may be contaminated with sewage. Protect yourself by wearing protective equipment such as gloves, protective eyewear, a face mask and rubber boots. Be sure to wash your hands frequently with soap and water.
  • Do not pump your septic tank. Pumping out a septic tank that is sitting in saturated soil may cause it to “pop out” of the ground. Newer systems are more likely to pop out than older systems because the soil may not have completely settled and compacted around the septic tank.
  • Try to avoid using any heavy machinery near the septic drain field or tanks in a saturated state, as they are especially vulnerable to damage under flooded conditions.
  • If sewage has backed up into a basement, clean the area and disinfect the floor. Use a chlorine solution of a half cup of chlorine bleach to a gallon of water when mopping the floor.
  • If you have a ground water well, do not drink the water until water testing proves it to be safe for consumption.

What steps should I take if I have a pumped system?

  • Do not operate the pump until floodwaters have receded and the groundwater table is below the pump chamber bottom/floor. Operating the pump to empty the chamber during high water events may cause the pump chamber to “pop out” of the ground due to buoyancy forces.
  • Avoid contact with any electric pump or equipment that may have been submerged during the flood. Have a licensed electrician inspect all electrical equipment before they are returned to normal operation.

What steps should I take if I have an Advanced Treatment Unit (for example: Ecoflo, Waterloo Biofilter, Puraflo, etc.)?

  • If you have an Advanced Treatment Unit, the system should not be used until the maintenance provider or licensed septic installer has verified proper system operation.
  • Do not pump treatment tanks until floodwaters have receded and the groundwater table is below the bottom/floor of the treatment tank. Pumping the tank during high water events may cause the pump chamber to “pop out” of the ground due to buoyancy forces. 
What should I do if I’m having septic problems after the floodwaters recede?
  • Do not pump out your septic tank until water levels recede below the bottom/floor of the tank. At best, pumping the tank is only a temporary solution. Under worst conditions, pumping it out could cause the tank to “pop out” of the ground due to buoyancy forces and may damage the inlet and outlet pipes.
  • Have your septic tank professionally inspected by a licensed septic installer or licensed sewage hauler if you suspect damage. Signs of damage include visible settling of the ground above the tank or an inability of the system to accept additional water. Most septic systems are not damaged by flooding since they are below ground and completely covered. However, septic tanks and pump chambers can fill with silt and soil and must then be cleaned. If the soil absorption field is clogged with silt, a new system may have to be installed as the there is no effective way to clean out the buried lines in an absorption field.
  • Have your tanks cleaned and/or repaired by a licensed septic installer or licensed sewage hauler as the tanks may contain dangerous gases and pathogens.

What should I do with my outhouse?

  • Ensure that the outhouse is still positioned over the pit. If the outhouse has been washed away, or collapsed, cover the open pit with sturdy boards to prevent accidents and the spread of disease. If water is in the pit, add two litres (two quarts) of unscented liquid chlorine bleach every three to four days until the water disappears.

When do you contact the OSSO or other Septic Regulator?

  • You must contact the OSSO or your local septic system Approval Agency for any repair or replacement of your sewage system. No permit is required for replacing electrical components such as pumps, control panels, etc.

Source: The Rideau Valley Conservation Authority

For more information on septic systems, visit The Rideau Valley Conservation Authority website (English only)

Cleaning up your home

Flooding is hard enough to deal with without being sick. Make sure to always wash your hands with soap and clean water before preparing or eating food, after using the toilet, after participating in flood cleanup activities, and handling articles contaminated with floodwater. (OttawasHealthIsInYourHands.ca) 

If soap and water are not available, and hands are not visibly soiled, use an alcohol-based hand rub (ABHR) that contains at least 60% alcohol. If hands are visibly soiled and running water is not immediately available: 

  • Remove visible soil using moistened towelettes
  • Once the visible soil is removed, clean hands with alcohol based hand rub (ABHR) containing at least 60% alcohol
  • Wash hands with soap and water as soon as it becomes available

Is it safe to enter my flood damaged home?

  • Ensure that a licensed electrician has determined that it is safe to turn on your power. Wear rubber boots as a precaution to reduce the risk of electrocution.
  • Use caution when entering your home as:
    • appliances, heating, sewage systems and electrical components pose a risk of shock or fire; and
    • chemicals such as gasoline and pesticides may have spilled and pose risks to skin and lungs.
  • Ensure that the building is structurally safe and that soil erosion, broken glass, holes in flooring, buckled walls, or deep water will not put you at risk of injury. Building Code Services can answer questions you may have about rebuilding or repairing flood damage in your home. Please contact City of Ottawa’s Building Code Services if:
    • Your home or any other structure on your property has experienced structural damage.
    • You want to arrange for a Building Inspector to visit your property.
    • You are unsure whether you need a Building Permit.
    • You have any questions at all about rebuilding, or need clarification on any of these points.
    • Building Code Services can be reached by email or phone 613-580-2424 ext. 29312
    • Building Code Services Frequently Asked Questions and Home Safety Quick Reference Guide
  • Make a plan for the recovery phase:
    • Should a professional flood recovery service be hired?
    • What does your home insurance policy cover?
    • How will discarded material be handled and disposed of?
    • What kind of support will your family need in the recovery phase?
      • Examples of support may include a caregiver for children or people with disabilities, pet sitter, assistance with meals, emotional support, and physical support to move items and clean up.

7 Steps to cleaning up your home and yard after a flood

STEP 1: Gather cleaning supplies
Here are items you may need for the cleanup:
  • Brooms, mops, rags, scrub brushes and sponges
  • Buckets, hoses and clean water
  • Trash bags
  • Cleaning detergents/soap and disinfectants (for your own safety, do not mix cleaning chemicals - especially bleach and ammonia).
STEP 2: Wear protective clothing and equipment

Wear personal protective equipment appropriate to the type of work you are doing:

  • The first step is to assess the area you will be working in (including electrical safety), the type of work you will be doing, and the type of equipment you will be using. Always ensure the work area is well ventilated and never use gas-powered equipment indoors.
  • Consider if you will need:
    • Protective footwear to avoid puncture or crushing hazards
    • Protective eyewear to avoid injury when hammering or using power equipment
    • Hearing protection if using noisy equipment
    • Gloves to prevent injuries from sharp objects as well as to avoid contamination
    • Respiratory protection against dust, mould spores. Use a properly fitted N95 mask.
STEP 3: Drain water and dry out flood-impacted areas
If you can clean and dry building materials within 48 hours, it is unlikely mould will develop. Many materials, however, absorb water and are unlikely to dry completely in a short time period (see Step 4).
  • Use pumps, pails and shop vacs (that can vacuum up water) to remove excess water from your home.
  • Use fans, dehumidifiers and open your windows to eliminate moisture.
STEP 4: Assess and sort damaged items to be cleaned, dried, repaired or discarded 
Identify and dispose of household items that have been exposed to floodwater and cannot be cleaned and dried within 48 hours. For information on how to prevent mould growth, refer to our mould webpage.
  • Remove and discard porous, wet building materials such as dry wall, insulation and ceiling tiles.

Other household items that are usually discarded because they cannot be properly cleaned and dried include:

  • Mattresses, pillows and duvets
  • Books, cardboard and papers
  • Rugs, carpets and under-padding
  • Leather, upholstered and particle board furniture
  • Soft toys
  • Medical supplies and medications
  • Cosmetics
  • Leather goods
  • Food items that have been exposed to flood water

Some of the above-mentioned items may be salvageable; however, the process may require professional assistance.

Take special care for opened containers of Hazardous Waste. If it’s corrosive, flammable or poisonous it’s hazardous waste. These types of products contaminate water and landfills and should never be poured down the drain or put out with your regular garbage. To help you dispose of these products safely, the City of Ottawa operates several one-day Household Hazardous Waste depots for City of Ottawa residents only. More detailed information is available on hazardous waste disposal at Ottawa.ca or by calling 3-1-1. Flood impacted areas may have special pickup instructions.

STEP 5: Clean and disinfect

Clean and disinfect all surfaces affected by floodwater to ensure bacteria, viruses, and potentially dangerous chemicals are removed. You may need to clean and dry hard surfaces several times.

How to clean hard surfaces:
  • Wear protective equipment – see Step 2
  • Remove visible debris
  • Clean hard surfaces with soap and water – see Step 1
  • Rinse with clean water
  • Keep things dry and the humidity low to control mould growth.
How to disinfect hard surfaces:
  • Disinfect cleaned surfaces with a diluted mixture of household bleach and water. Protect your skin and eyes when mixing.
  • Dilution rates for disinfecting hard surfaces:
    Recommendations for cleaning and sanitizing household surfaces and items
    Amount of bleach and water to mix  
Area or item to be cleaned Bleach amount Water amount Cleaning steps

Surfaces that do not soak up water and that may have touched floodwater.

Examples: Floors, stoves, sinks, certain toys, countertops, flatware, plates, and tools
1 cup
(240 mL)
5 gallons (18.9L)
  1. Clean surface with soap and warm, clean water
  2. Rinse with clean water.
  3. Sanitize using a mixture of 1 cup (240 milliliters) of household chlorine bleach in 5 gallons of clean water.

Source: CDC - Cleaning and Sanitizing with bleach after an emergency

Cleaning up flood-associated mould

Homeowners may clean small patches of mould up easily (3 square meters or less – equivalent to the surface area of a queen-sized bed) areas of mould contamination bigger than this may need professional attention. Remember, moisture control is the most important step for preventing mould from growing again: ensure that the material or object has completely dried out, that the source of moisture has been removed, and that the humidity in the air is kept low.

Professionals have experience dealing with airborne mould spores. They have the proper protective clothing and equipment to remove and dispose of mouldy materials.

  • Think of your personal safety when dealing with mould: Wear protective clothing such as rubber gloves, eye protection and a properly fitted N95 mask and follow this chart:
   Recommendations to clean mould growth off hard surfaces
    Amount of bleach and water to mix  
Area or item to be cleaned Bleach amount Water amount Cleaning steps

Mould growth on hard surfaces.

Examples: Floors, stoves, sinks, certain toys, countertops, flatware, plates, and tools

1 cup (240 mL) 1 gallon (3.89L)
  1. Mix 1 cup (240 ml) of bleach in 1 gallon of water. 
  2. Wash surfaces with the bleach mixture.
  3. If surfaces are rough, scrub them with a stiff brush.
  4. Rinse surfaces with clean water.
  5. Allow to air dry.

Source: CDC - Cleaning and Sanitizing with bleach after an emergency

  • Keep mould from growing by keeping rooms dry. Use fans, dehumidifiers and open your windows to reduce moisture in your home. Commercial anti-mould sprays are available to control mould growth during the drying phase. This should not replace cleaning and disinfecting.
  • Discard absorbent or porous materials that cannot be washed and dried as mould can grow on or fill in the empty spaces and crevices of porous materials.
Washing flood damaged fabrics

A laundromat can be used for washing large quantities of clothes and linens if your well and septic system are not ready for use following a flood.

If they are ready:

  • Wash fabrics using clean uncontaminated water.
  • Wear rubber gloves and a properly fitted N95 facemask to protect yourself when handling dirty clothes.
  • Scrape and shake dirt from fabrics and rinse or wash as soon as possible.
  • Wash small loads and a full water level. Do not overload washer.
  • Wash with hot water and laundry detergent. Add household bleach according to product label.
  • Heavily soiled items may need more than one wash to get clean. If the rinse water is dirty or cloudy, clothes should be washed again until the rinse water is clear.
  • Dry on the hottest setting once clothes are clean.

Learn more about Mould

Mould Factsheet - [PDF 465 KB]

STEP 6: Dry out your home and lower humidity
IMPORTANT : Do not paint over or cover mould with fabric or wallpaper, as the mould will continue to grow underneath and linger in your home. It may take several weeks to completely dry out a flooded area.

A musty odour may signify growth of mould or bacteria.

Remove waterlogged items from the home as soon as possible.

  • Open doors and windows
  • Open closets, drawers and cabinet doors
  • Use fans and run one or more dehumidifiers as needed.
STEP 7: Cleaning your yard
 Keep children and pets out of the area until clean-up has been completed.
  • Replace sand in sandboxes and clean any play structures that may have been contaminated.
  • Turn the soil over in vegetable gardens. Do not consume any already growing produce from vegetable gardens impacted by floodwater.
  • Depending on the season, standing water can pose a health risk by providing a place where insects such as mosquitoes can reproduce. Drain water as soon as possible (e.g., pails, old tires, or other containers with standing water).
  • Dispose of debris and garbage from your home as soon as possible to ensure rats, mice, raccoons and other vermin are not attracted to make their homes on your property. (Do not touch or approach animals you do not know, even if they appear friendly.)

Based on:

Alberta Government - Private Sewage and Water Well Systems Recovery and Start Up After a Flood: Cleaning and Sanitizing with Bleach after an Emergency

CDC - Cleaning and Sanitizing with Bleach after an Emergency.

The City of Calgary - Cleaning up after a flood

After a flood Information Package - [PDF 166 KB]

Responding to Stressful Events

The psychological impact of a stressful event can be immediate or delayed, and those affected directly or indirectly can feel a range of emotions and reactions. In the wake of stressful events our reactions can affect us physically or emotionally. It can affect our thinking.

Being resilient helps us recover and work through challenges in a positive way. Sometimes, we need a little help. It's OK Not to be OK

Contact Us