FORT ST. JOHN, B.C. – The Peace River Regional District hosted a community meeting for the residents of Old Fort on Monday at the North Peace Cultural Centre.
Many concerned and frustrated residents came out to listen to the updates on the landslide status.
The meeting included a presentation of the completed geotechnical report, slope monitoring system, and discussions of the DRAFT evacuation plan.
To present the completed geotechnical report was Eric McQuarrie of Westrek Geotechnical Services.
McQuarrie says the movement of land has ceased for the time being in part to seasonal changes.
“The movement has ceased, but it’s what we call suspended. We won’t call it inactive yet; it has to go through a full cycle where we don’t see any movement; have a little bit more confidence that it has stopped. This case here is just suspended because we got into the cold and we got into lower groundwater levels.”
McQuarrie says a change in groundwater levels and pressures is a likely cause of the landslide and not the gravel pit alone.
“Groundwater pressures are a significant contributing factor to most large landslides; therefore, the causes of the landslide would most likely be factors that increase groundwater levels or piezometric pressures. The removal of overburden soils as part of the gravel pit operation could have impacted the groundwater level by greatly reducing the volume of soil capable of absorbing groundwater within the vadose zone.”
Some residents in attendance were pretty upset by the report as they say it does not list the gravel pit as a contributing factor to the landslide as they have large stockpiles of gravel on top of the hill.
McQuarrie says the weight of the gravel pit stockpiles is pretty minor in contributing to the landslide.
“The weight of the stockpiles is pretty minor. Weight is not an issue, and the weight hasn’t changed. They haven’t really changed, what’s happened is the groundwater has changed.”
McQuarrie adds that while most slides are caused by loading issues, he believes this is not the case in Old Fort, stressing that the purpose of this report is to determine imminent hazard and not the precise cause of the slide.
“In most slides, the loading is an issue. In this one, we haven’t gone into enough detail, and that’s going to be a different report. You have to keep in mind that what we’re trying to deal with the imminent hazard.”
McQuarrie says changes in the landslide status depends on the weather conditions.
“It will all come down to how much rain you will get in the Spring, how much snow you get over the Winter, and how things melt. That’s when the next risky period is going to be when it comes to Spring.”
Highlighted in the report, the main elements at risk that will be monitored will be the southern part of the gravel pit, the temporary access road, and Old Fort Road.
According to McQuarrie, they are still unsure as to how deep the landslide is and the rate of its movement.
McQuarrie’s presentation ended as some residents continued to argue with him about the quarry and how they claim it is a contributing factor to the landslide.
Following McQuarrie’s presentation Nikki Hogg, of Ministry of Transportation, gave an update on the current road status and the monitors that have been set up to watch the progress of the slide.
Hogg says there are currently four thresholds that collect data that monitor slide activity.
“We have four different thresholds, and that triggers different responses. They’re pretty conservative right now just because we want to see how the slide’s reacting. Since we’ve installed them since the slide has slowed down and has stopped moving, we haven’t seen any alerts from those monitoring systems and where they’re placed right now, right around five centimetres is when we will start to trigger an alert, and we will be sharing that information with the Regional District and other affected agencies to make some decisions on whether we need to close the road, increase patrol, how it’s affecting the road, and those types of things.”
Hogg assured the residents that the Ministry would continue to monitor the condition of the road.
Regional Chair, Brad Sperling, was on hand to report some resolutions that have been sent by the Regional District to the Provincial Government.
Some of those resolutions include that the government takes full responsibility to monitor the landslide movement and that the Ministry of Public Safety should launch an investigation into the cause of the slide. Sperling feels this should not be PRRD’s responsibility.
Some residents wanted to make sure that the Regional District is on board when it comes to them staying in there homes as long as possible.
Sperling responded saying, “You will be, as long as it’s possible and if you’re not in danger, you will be staying there.”
Sperling also assured residents that the Regional District has an evacuation plan set in place if any further sliding were to occur.
At the end of the meeting, residents stated that they wish to be better informed when it comes to the releasing of information about the landslide status, as they feel they are the biggest stakeholders involved in this situation since it is they’re homes and livelihood that would ultimately be heavily affected by the landslide.
The District says it will continue to improve ways of keeping residents informed on updates as they become available.
The full geotechnical report can be viewed on the Regional District’s website.