The City of Coquitlam, in its efforts to proactively manage the risk of landslides, has completed studies into the stability of the Chines Escarpment slope. Overall, the studies found that the landslide risks are currently deemed to be tolerable. The studies were completed in two phases; 1) qualitative assessment, and 2) detailed geotechnical investigation.
The first phase involved a qualitative assessment to estimate the risk of landslides and identify areas of concern for further evaluation. This assessment was completed by Associated Engineering as part of the Chines Integrated Stormwater Management Plan which was a joint project led by Metro Vancouver with participation from the cities of Coquitlam and Port Moody.
Seven properties were categorized as high or very high risk and a further 10 properties were identified as potentially being exposed to slope failures. The report recommended that these properties be evaluated by a detailed geotechnical investigation to more accurately quantify the risk to residences.
The City hired Golder Associates to perform the detailed geotechnical investigation which involved a drilling program and laboratory testing to establish subsurface conditions. After the subsurface condition were determined, the stability of the slopes were analyzed under static and seismic conditions to calculate the Factor of Safety (FoS) against failures impacting residences. A landslide runout assessment was also completed to determine whether a slope failure would impact any downslope properties. Golder’s report determined that all residences meet accepted FoS criteria for slope failure and are within generally accepted risk tolerance criteria.
The slope stability studies did not identify an imminent risk of landslides for the properties assessed. However, property owners near ravine crests should regularly monitor the slopes for signs of instability such as ground movement, cracks in the ground, leaning trees or leaning structures. If any signs of slope movement are observed, homeowners should notify the City’s Engineering & Public Works department at 604-927-3500 or firstname.lastname@example.org.
Documents & Reports
Engineering & Public Works Customer Service
Engineering Emergency Services for Water, Sewer and Roads
24 Hours a Day, 7 Days a Week
If this matter is urgent, please call our Engineering and Public Works Customer Service line at 604-927-3500 (24 Hours / 7 Days a Week).
Engineering Customer Service Email: email@example.com
Please Note - The Engineering and Public Works email address is only monitored during regular business hours (Monday to Friday: 8:00 a.m. - 5:00 p.m.).