Basement Flood: Safe First Steps for Ontario Homeowners

Flooding can involve electrical, structural, and contamination hazards. Start with safety, record the condition of the property, and check your insurer's instructions before making non-emergency disposal decisions. This article is general homeowner information; it does not replace directions from emergency services, utilities, public health, or your insurer.

Safety before cleanup

Do not enter standing water if there may be an electrical hazard. Health Canada advises avoiding electrical shock, keeping electrical cords out of water, and shutting off power to the flooded area at the breaker only when it is safe to do so. If you are unsure, contact a qualified electrician or your utility.

• Leave the area and contact emergency services if there is a fire, gas odour, immediate structural concern, or another urgent hazard.
• Keep children, pets, and people with respiratory conditions away from sewage-contaminated water and materials.
• Do not use combustion equipment intended for outdoor use indoors; Health Canada warns of carbon-monoxide risk.
• Wear appropriate protective equipment when handling wet or contaminated material.

Document the loss

When it is safe, photograph and video the affected rooms, water level, visible source, and damaged contents before cleanup changes the scene. Keep a dated log of calls, actions, receipts, and correspondence. The Canadian Red Cross flood-recovery resources (opens in a new tab) include a home inventory checklist and insurance information that may help organize records.

Do not discard property solely because it is damaged before checking the instructions from your insurer or adjuster, except where safety or public-health advice requires disposal.

Water and contamination

The water source affects the precautions required. Water from a supply line is different from water that may contain sewage or flood contamination. Health Canada says sewage-contaminated water and materials can create an infection risk and may require additional precautions and disinfection. When the source is unknown, suspected to involve sewage, or has entered from outside, avoid direct contact and seek suitable advice before cleanup.

Do not assume a material can be kept just because its surface feels dry. Porous materials exposed to contaminated water or left wet for a prolonged period may need a different cleanup or disposal decision.

Drying and cleanup

Health Canada says rapid drying is important and notes that a home and furnishings are less likely to grow mould if dried within 48 hours. Its flood-cleanup guidance recommends removing standing water and debris, cleaning salvageable hard surfaces with an appropriate unscented soap solution, and ventilating or dehumidifying the space until it is dry.

• Remove standing water only if it is safe to do so and the source is understood.
• Open doors or windows when weather and safety permit, or use dehumidification as appropriate.
• Do not rely on surface appearance alone to decide whether concealed materials are dry.
• Contact the local public health authority for local disposal guidance if sewage contamination is suspected.

Read the Health Canada flood-cleanup guidance (opens in a new tab) for more detail about safety, drying, and contaminated materials.

Insurance questions

Coverage depends on the policy, cause of loss, applicable endorsements, and the facts of the event. Contact your insurer or broker promptly, ask what documentation they require, and confirm whether emergency mitigation can proceed. The Insurance Bureau of Canada's flood information (opens in a new tab) and the Financial Consumer Agency of Canada (opens in a new tab) explain that coverage can vary by policy and water event.

When to seek help

Consider a property-specific assessment when flooding affects multiple materials or rooms, the water may be contaminated, a moisture source continues, or there are concerns about concealed moisture. Ask any provider what work is proposed, what safety measures will be used, and what records you will receive. You can also review the water-damage assessment checklist before discussing the conditions at your property.

If a provider recommends post-drying air quality testing, ask what question it will answer, how it will affect the scope, and what records you will receive.