A map from the Geological Survey of Canada showing the line of a possible seismic fault on Douglas Channel.
A tsunami hazard and a possible seismic fault have been identified in the Douglas Channel near Kitimat — the proposed site of the Enbridge Northern Gateway pipeline and at least three liquefied natural gas projects.
The information is included in a scientific paper by the Geological Survey of Canada and the Department of Fisheries and Oceans uncovered by Huffington Post B.C. blogger and journalist Robin Rowland. The study was part of a legal filing to the Joint Review Panel that’s assessing the proposal for a pipeline to carry bitumen from the Alberta oilsands to northern B.C.
The October 2012 report says two giant landslides in the Douglas Channel — perhaps 5,000 to 10,000 years ago — may have triggered major tsunamis, and that the slides were possibly caused by an earthquake on the fault line.
Scientists conclude that the slides appear to have left very steep slopes at or near the shoreline that could be susceptible to future failure events, reported Rowland on the Northwest Coast Energy News.
According to the study:
The fault must be considered a potential trigger for the submarine failure events... The triggers for the failures have not been defined; however, their proximity to a potentially active fault represents one potential source. The failures probably generated tsunamis during emplacement and conditions exist for similar failures and associated tsunamis to occur along this segment of Douglas Channel in the future.
Natural Resources Canada told Rowland scientists are currently using high-resolution scans of the Douglas Channel seafloor to create models of potential wave heights and speeds.
“Only through the development and application of this type of tsunami modelling will it be possible to gauge the level of hazard posed by the identified submarine slope failures to shore installations and infrastructure, or to devise ways to effectively mitigate the impacts of future such events,” the department said in a statement.
The federal government has offered to bring the scientists to the Joint Review Panel as witnesses during the final hearings.
Enbridge has stated it will carry out further geological survey during the detailed design phase for the terminal.
CLOCK IS TICKING TO 'BIG ONE'
While British Columbians have long been warned of “The Big One,” two studies released last month are pegging a megathrust earthquake as arriving sooner and causing more devastation than ever predicted.
The fault line closest to Kitimat is the Queen Charlotte Fault Zone, which has been called "Canada's San Andreas fault" and triggered an 8.1 magnitude quake in 1949. But the area with the most potential for a devastating quake is the Cascadia Fault which stretches from northern California to southern Vancouver Island.
A study based on 13 years of research concluded the clock is ticking on a major earthquake striking the Cascadia zone in the next 50 years.
The research, published in August by the U.S. Geological Survey, is the most comprehensive overview of the Cascadia zone, detailing 19 earthquakes — between magnitude 8.7 and 9.2 — in the last 10,000 years.
"By the year 2060, if we have not had an earthquake, we will have exceeded 85 percent of all the known intervals of earthquake recurrence in 10,000 years," said co-author Jay Patton. "The interval between earthquakes ranges from a few decades to thousands of years. But we already have exceeded about three-fourths of them."
A second study, published in the journal Geology, used fault-zone temperatures along the Pacific Coast to conclude that epicentres of potential earthquakes could happen up to 55 kilometres farther east than previous research. That means coastal cities such as Vancouver, Victoria and Seattle could suffer greater impact from The Big One.
For more on the Geological Survey findings, read Robin Rowland's blog on The Huffington Post B.C.