Landslides and sinkholes
Learn about landslides, sinkholes, groundwater contamination and what can happen when bedrock – the rocky material found under soil, sand and gravel – is unstable.
On this page Skip this page navigation
Many landslides occur within Ontario. These events can damage property and hurt people.
Sinkholes, landslides and groundwater contamination can happen due to:
- building or construction in unstable areas
- loss of vegetation, heavy rainfall or water from spring runoff
- earthquake, explosions and heavy vehicle traffic
Risk areas include bedrock composed of unusual rock formations or land that’s composed of unstable soils.
Areas with unstable soils and bedrock include:
- the Niagara Escarpment including the Bruce Peninsula
- Guelph, Rockwood and Elora
- Manitoulin Island
- portions of eastern Ontario
If you are instructed by emergency officials to evacuate, do so immediately.
If you are indoors:
- During a severe storm, stay alert and awake. Many deaths from landslides occur while people are sleeping.
- Listen to local news stations for warnings of heavy rainfall. Check for emergency information and alerts.
- Gather supplies in case you must leave immediately or if services are cut off. Keep in mind each person’s specific needs, including medication. Do not forget the needs of pets.
If you are outdoors:
- If you notice any hazard signs, contact your local authorities.
- Keep yourself and family well away from landslides and sinkholes.
- Notify all local occupants and authorities.
Take the following steps so you and your family are prepared in the event of a landslides and sinkholes:
- If you live in a risk area or are buying or building property check with your municipality or municipal planning authority to ensure the property isn’t in a designated hazard area.
- follow appropriate land use measures - avoid building near steep slopes, close to mountain edges, near drainage ways or along natural erosion valleys.
- Get a ground assessment of your property.
- Protect your property by planting ground cover on slopes and building retaining walls.
- Inspect property for circular pattern of ground cracks, localized, gradual ground settlement, formation of small ponds as rainfall accumulates in new areas.
- Mark the sinkhole for safety and to restrict access (use posts with caution tape or rope).