VIDEO: Investigators probe Bute Inlet landslide in bid to understand glacial retreat

The slide swamped the Southgate River, around 13 km downhill from the initial incident. Photo supplied by Hakai Institute.The slide swamped the Southgate River, around 13 km downhill from the initial incident. Photo supplied by Hakai Institute.
Elliot Lake, where the slide initially hit on Nov. 28. Photo supplied by Hakai InstituteElliot Lake, where the slide initially hit on Nov. 28. Photo supplied by Hakai Institute

A research team is probing a devastating landslide on the B.C. central coast in the hopes of predicting if and when another slide may be coming.

The Hakai Institute, which operates an ecological observatory on Quadra Island, near Campbell River, conducts long-term research in the coastal regions of the province, including seismic research and ocean-based ecological research. Part of its research area is Bute Inlet — site of the Nov. 28 slide that launched a 100-metre wave that washed out the Southgate River.

The institute had been monitoring the area prior to the slide, and afterwards sent out researchers for preliminary data on what the incident will mean for salmon habitat in the inlet.

Hakai founder Eric Peterson said that a team did a flyby on Dec. 22, which includes a lidar (light detection and ranging) scan, which is similar to radar, but with laser light instead of sound waves.

“The instrument is a specialized laser scanner,” Peterson said. “We make multiple passes and thereby build up a very precise 3D model of the landscape. Fortunately, we have recent lidar/3D models from before the landslide from our ongoing research.”

The lidar scan will shed some light on the stability of the mountain and the risk of other slides, as well as information on how it happened and whether or not it is likely to happen again.

“We hope to be able to conduct a detailed comparison of the ‘before’ and ‘after’ 3D lidar models, and thereby be able to work out exactly what material moved from where to where,” he said. “The current model may help us predict whether the mountain is stable now, or whether another collapse might be coming.”

Peterson explained that the slide highlights the issue of glacial retreat along the coast. Whether or not the glacier’s retreat was a direct cause of the Bute Inlet slide is to be determined, but retreating glaciers often cause instability and make the landscape more sensitive to landslides.

According to a video posted on the Hakai Institute website, the landslide occurred at around 6 a.m. on Nov. 28. The initial event had an equivalent shock as a 4.9 earthquake, and sent roughly 10 million cubic metres of material into Elliot Lake, just north of the end of the inlet.

That material caused a glacial lake outburst, which sent a 100-metre wave down the narrow creek, uprooting trees and carving a deep channel through the valley. Once the water hit the ocean, it caused a current of high-turbidity water to extend out 70 km.

Story continues below…

Researchers measured the temperature of the water over a few weeks following the slide, and recorded a 0.5 degrees Celsius dip in deep water temperature. A temperature change can effect the amount of dissolved oxygen and the pH of the water. Increased sediment in the ocean is also likely to impact which bacteria and phytoplankton can grow, which has a direct effect on the salmon in the area.

Since staff have been off for the holidays, analyzing the data has taken some time. The video posted on Dec. 22 is an introduction to the upcoming data and preliminary research, and more information will be made available as it comes.

Hakai researchers are working closely with the Homalco First Nation, since the incident took place on their resource management area.

“We expect to be working together in the coming years on research, remediation, recovery, stewardship of salmon, forestry, and all the elements of this complex & dynamic ecosystem,” Peterson said.

For more news from Vancouver Island and beyond delivered daily into your inbox, please click here.

RELATED: 100-metre wave causes massive washout in Bute Inlet

RELATED: Generation of B.C. salmon likely wiped out by central coast landslide



marc.kitteringham@campbellrivermirror.com

Like us on Facebook and follow us on Twitter

Campbell RiverEnvironmentLocal News

Get local stories you won't find anywhere else right to your inbox.
Sign up here

Just Posted

COVID cases in the Bella Coola Valley have dropped to just four active cases (file photo)
Active COVID cases drop to four; schools re-open for face-to-face instruction

A total of 63 cases were recorded with 59 now out of isolation

People skate on a lake in a city park in Montreal, Sunday, January 10, 2021. THE CANADIAN PRESS/Graham Hughes
The end of hugs: How COVID-19 has changed daily life a year after Canada’s 1st case

Today marks the one year anniversary of COVID-19 landing in Canada

Joyce Cooper (left) said she had to set an example for Tsilhqot’in communities by sharing her COVID-19 positive results. (Photo submitted)
Tsideldel off-reserve member documents experience of COVID-19

We should all be supporting one another and not judging each other, says Joyce Cooper

A health-care worker prepares a dose of the Pfizer-BioNTech COVID-19 vaccine at a UHN COVID-19 vaccine clinic January 7, 2021. THE CANADIAN PRESS/Nathan Denette
Employers might be able to require COVID-19 vaccination from employees: B.C. lawyer

‘An employer must make the case’ using expert science, explains lawyer David Mardiros

Nuxalk Public Health Nurse Sophie Mack is all smiles as she vaccinates her dad, hereditary chief James Mack Sr., with his first dose of the Moderna vaccine (photo submitted)
Cases drop as vaccine continues to roll out in Bella Coola

Seniors at Mountain View Lodge, Nuxalk elders, hospital staff and long-term care residents have all started to receive their vaccines so far

Dr. Penny Ballem, a former deputy health minister, discusses her role in leading B.C.’s COVID-19 vaccination program, at the B.C. legislature, Jan. 22, 2021. (B.C. government)
B.C. holds steady with 407 new COVID-19 cases Tuesday

14 deaths, no new outbreaks in the health care system

Worker at Swartz Bay terminal on Monday, January 20, 2020. (THE CANADIAN PRESS/Chad Hipolito)
Former BC Ferries employee alleges he was fired because of his race

Imraan Goondiwala has been granted a BC Human Rights Tribunal hearing

Rodney and Ekaterina Baker have been ticketed and charged under the Yukon’s Civil Emergency Measures Act for breaking isolation requirements in order to sneak into a vaccine clinic and receive Moderna vaccine doses in Beaver Creek. (Facebook/Submitted)
B.C. couple who travelled to Yukon for COVID vaccine ineligible for 2nd dose until summer

The province is ensuring those eligible to receive the vaccine get the second shot within 42 days

(File)
Mask dispute in court leaves Vancouver cop with broken leg

Man allegedly refused to put on a mask and resisted arrest

Cannabis bought in British Columbia (Ashley Wadhwani/Black Press Media)
Is it time to start thinking about greener ways to package cannabis?

Packaging suppliers are still figuring eco-friendly and affordable packaging options that fit the mandates of Cannabis Regulations

(Kraft Dinner/Twitter)
Kraft Dinner launches candy-flavoured mac and cheese just in time for Valentine’s Day

Sweet and cheesy treat will be here just in time for the cheesiest holiday of the year

SAR crews worked late into the night Tuesday to rescue an injured snowboarder in North Vancouver. (Facebook/North Shore Rescue)
Complicated, dangerous rescue saves man in avalanche near Cypress Mountain

North Shore SAR team braves considerable conditions to reach injured snowboarder

A Cessna 170 airplane similar to the one pictured above is reported to be missing off the waters between Victoria and Washington State. Twitter photo/USCG
UPDATE: No sign of small plane that went down in waters south of Vancouver Island

Searchers out on both sides of border between Victoria and Port Angeles

Most Read