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Geotechnical News • December 2018
GEOHAZARDS
• 2013: Canmore floods. Debris
floods in the Bow River valley in
Alberta caused millions of dollars
of damage and forced communi-
ties to consider the real hazards of
building on steep mountain creeks.
Building on work done for the
DNV, Canmore developed a steep
creek policy in 2016.
• 2014: Mount Polley tailings pond
breach. 24 million cubic meters
of water and mine tailings were
released to BC waterways in
Canada’s first tailings dam failure.
In addition to direct impacts, this
failure resulted in substantial scru-
tiny of the company, individual
engineers, and the regulation.
• 2016: Landslide generated pipeline
rupture into the North Saskatche-
wan River. Costing on the order of
100 million dollars, this landslide
resulted in dramatic increases in
regulatory oversite in the province
of Saskatchewan, and the bolster-
ing of pipeline integrity programs
for multiple companies, including
a movement towards quantitative
probability of (pipe) failure assess-
ments.
Geohazards 7
Over this period, Geohazards confer-
ences were held across the country,
at Edmonton, Quebec City, Kelowna
and Kingston. The papers presented
at each conference were notoriously
high caliber, and in their own way,
mark the progress of the state of the
art. Most recently, Geohazards 7 was
held in Canmore Alberta, home to the
debris floods of 2013, from the steep
mountain streams that surround local
communities in the Bow Valley. Like
previous conferences, Geohazards 7
was a good proxy for the state of the
art in Canada today. Below are some
of the papers that I recall. The pre-
senter’s name is supplied in case the
reader would like to follow up with
one of them specifically.
Following a retrospective showing
the evolution of landslide hazard and
risk assessment in Canada (Doug
Van Dine), the conference opened by
focussing on communities and com-
munity emergency response: building
flood resiliency through risk com-
munication (Sandy Davis), protecting
workers through field level hazard
assessment tools (Katleen Baker), and
lessons learned during steep creek
mitigations (Emily Moase). We were
introduced to community maps that
showed probability of hazard by return
period and to the challenges in design-
ing effective debris flow structures.
We looked at how LiDAR is chang-
ing the way we identify landslides in
eastern Canada, and how geotechni-
cal data can provide clues about their
sequence and activity state (Baolin
Wang). We were introduced to new
techniques (or testing of existing tech-
niques) for estimating retrogression
and runout hazards in sensitive clays
(Dominique Turmel, Suzanne LaC-
asse) that substantially move the sci-
ence forward. We were introduced to
a new type of landslide (or new to this
writer at least), the downward trans-
lational landslide, used to describe
the mechanism behind the St. Fabien
Landslide (F. Tremblay-Auger).
An up to the minute estimate of how
climate change is manifesting was
addressed in a keynote talk (Markus
Schnorbus). Canada is, in general,
experiencing an overall decrease in
snow and increase in rain, leading to
intensification of extreme storms (~5%
intensification/degree of warming)
with the top 1% of extremes seeing the
biggest impacts. The 1950’s 20-year
storm is now the 15-year storm.
A changing climate drives mate-
rial changes in geohazards and we
discussed some the changes related to
snow avalanche risk (Bruce Jamieson),
tools and mitigation to address snow
avalanches (Brian Gould, Michael
Laws, Alan Jones), glacier retreat and
landslides (Gio Roberti), and debris
flood prediction and characterization
(Matthias Jakob).
Canmore engineer Andy Esarte pro-
vided a compelling first-hand account
of the 2013 floods, a cautionary tale of
the danger of overlooking geohazards,
and the dramatic impact they have on
communities. This was followed by
several talks on risk and mitigation
of steep creeks (Félix Camiré, Kris
Holm, Cesar Oboni) and rocky slopes
(Renato Macciotta, Helene Hofmann,
Andrew Mitchell, Kristen Tappenden,
Gernot Stelzer, Jason Pellett, François
Noël).
Innovative use of technology was
demonstrated in a keynote that looked
Figure 3. The 2010 Saint Jude landslide in Quebec (photo by R. Couture).
