Skip to content
Join our Newsletter

Pemberton to consider landslide monitoring

River gauging could alert Village about landslide activity

One month after the second biggest landslide in Canadian history, Pemberton is ready to consider a warning system.

Pemberton Mayor Jordan Sturdy suggested at a Sept. 14 council meeting that the Village of Pemberton look into various options with regard to monitoring, worried as he is that woody debris from the Mount Meager landslide could float down the Lillooet River during the next flood event.

"It appears to me that we should be looking at a river gauge in the Upper Lillooet," he said during his mayor's report. "Wherever is appropriate, to give us real-time data, similar to our gauge up here on Farm Road East. This allows us to monitor whether there's water in the river.

"We can see the results form the slide. The gauge just drops, you could see right away that something happened, then you could start to see it coming up."

Another reason that monitoring might be helpful is that it could allow for a quicker response to landslide events. A 40 million cubic metre slide fell from the summit of Mount Meager at about 3:25 a.m. on the morning of Aug. 6. It ran all the way down Capricorn Creek, picked up material as it flowed across Meager Creek and created a natural dam there.

The dam partially blocked the Lillooet River as three million cubic metres of water backed up behind it. Fears of flooding were eased when the water cut a 25-40 metre incision in the dam.

The first geoscientist was on the scene at 1 p.m. but officials discovered the breach at 10 p.m., 19 hours after the landslide happened.

"We had no idea what was going on that night," Sturdy said. "We had no idea how that thing was going to breach. We didn't know if it was going to breach imminently or all at once, and whether we'd have that big surge or not."

Officials in Pemberton, however, weren't always so willing to install an early warning system. When the Meager slide occurred it emerged that the Squamish-Lillooet Regional District received a report two years ago encouraging it to install such a system in the Meager area.

The SLRD ultimately decided against it, opting instead to publish an annual report about the risks at Mount Meager.