Wildfires can change the landscape: know the risks of landslides and flooding

The Quilpituk Creek wildfire may be out, but risks in previously burned areas can remain significant and caution is still needed in all areas affected by wildfire.

Residents within the Regional District of Central Okanagan’s Electoral Area West should be aware of landslide risk. Burned landscapes and vegetation loss can increase the risk of natural hazards such as landslides and flooding. This information can help residents recognize potential hazards and take appropriate action if conditions change.

Post-wildfire Natural Hazards Risk Assessment

The Province of B.C. has completed an initial post-wildfire natural hazards risk analysis for the Quilpituk Creek wildfire area. The report examines how post-wildfire changes to vegetation, soils and surface conditions may affect slope stability and flooding hazards.

It is important for residents living on, or adjacent to, wildfire-affected properties and waterways to monitor for changed conditions, particularly during or after an intense rain event (e.g. >10 mm of rain falling in under 30 minutes) or rapid snow melt event. The likelihood for post-wildfire instability and higher runoff rates declines over time, with the first few years being the most likely, and decreasing afterwards. Depending on site conditions, effects may persist for a longer period of time. 

Be informed. Be ready.

Get to know the land and waterways near your property. The best way to prepare is to watch for changes that could signal a landslide or damaging flood event. These may include:

• Sudden changes in stream flow.
• Rapid changes or surges in the amount of water (e.g. changes in volume) or water that quickly changes from clear to murky.
• Abnormally dirty water.
• Accumulation of large logs or debris.
• A quick buildup of mud, sand, gravel or rocks in a flat part of a creek or in a ditch
• New cracks near the top of the slope.

Falling rocks or boulders or flowing or sliding soil. This may precede a much larger landslide.

Pay close attention to weather forecasts, particularly those that include thunderstorm or heavy rainfall warnings. Rapid snowmelt at higher elevations caused by warm temperatures is another critical condition to monitor, as it can increase runoff and the risk of flooding, landslides and debris flows.

It is recommended that property owners situated downslope of a wildfire ensure that drainage structures (i.e. ditches and culverts) are maintained to be free of sediment and debris, whether or not these structures have experienced flowing water. This will allow for the passage of higher than usual post-wildfire runoff conditions.

Detailed hazard assessment underway

The Province of B.C. is developing a detailed assessment of post-wildfire hazards in the area. Once completed, the assessment will be posted on the Assessment Explorer Dashboard. Residents and property owners are encouraged to check back for updates and the latest information.

If you notice signs of a landslide or debris flow, call the Province's 24-hour toll-free line at 1-800-663-3456 or contact the Wilson’s Landing Fire Department, North Westside Fire Rescue, or RCMP.

Learn more about landslide preparedness from PreparedBC.