WC142 MayJune 2025 - Magazine - Page 15
When operational, the Springbank O昀昀-Stream Reservoir Project (SR1) will
work in tandem with the Glenmore Reservoir and other 昀氀ood mitigation
infrastructure in and around Calgary.
While the Province took the helm as project owner and
operator through Alberta Transportation and Economic
Corridors, the city remained intricately involved because not only
is Calgary vulnerable to flooding but the new reservoir needs to
work lock-step with the municipally owned Glenmore Reservoir.
“We have to be able to throw the switches on both of those
structures and be able to optimize the flood mitigation capacity
for both,” Frigo explains.
Still, the two parties couldn’t go it alone. The project site lies
entirely within Rocky View County, which also experiences
flooding, and therefore needed to be actively engaged, as did
adjacent property owners. And, while the project site is not
on reserve lands, the project is on the traditional lands of the
Tsuut’ina Nation. The Tsuut’ina Nation formally objected to
the use of a dry dam and raised concerns about the likelihood of
flooding on their lands. “The concern was partly in relation to the
engineering of the project and partly about inherent and treaty
rights being respected,” says Terry Braun, general counsel for the
Tsuut’ina Nation. Following discussion and negotiations, and an
agreement to address the concerns, the Tsuu’ina Nation withdrew
the objections it had filed with the Impact Assessment Agency
of Canada. “We wanted to make sure that the environment was
protected and there wasn’t a negative impact to the plants, fish and
wildlife in the area,” Braun says. “It’s in everybody’s best interest
that action is taken to mitigate future flooding.”
With objections dropped and approvals in hand, the Province
provided the lion’s share of funding, the federal government
contributed $168.5 million, and the city supplied in-kind resources
such as research and engineering support as well as collaboration
on studies and joint investments in a flood forecasting platform
and monitoring systems. Shovels finally hit the ground peripherally
in 2019, and by 2022 construction was well underway. Work
WAT E R C A N A D A . N E T
included building water diversion structures
on the Elbow River, cutting a four-kilometre
channel into the bedrock to divert river
overflows into the reservoir, then building
the dam. “It’s an earthen structure, but the
earth materials had to be carefully engineered,
compacted, and placed to ensure they’ll be
stable and waterproof when the reservoir is in
operation,” says Calgary’s Frank Frigo.
Construction has been relatively
straightforward, though the project team
prepared for complex hydraulics, including
the need to manage materials that can float
or be carried by a river the size of the Elbow
but which can block diversion systems, by
building a smaller-scale model and using
three-dimensional modelling. “We see massive erosion when we
have these large floods, and the velocities are enough to move
trees and boulders,” Frigo says. “So one of the really important
aspects from a hydraulic engineering standpoint of designing
this infrastructure was to design it in a way that debris will either
be shunted through the structures or sequestered outside.”
While Springbank stands to mitigate flood risks significantly,
no single system is bulletproof. “We recognize that larger
events can occur, so a number of other resilience measures
have been layered on top,” Frigo says. These include expanding
the Glenmore reservoir, as well as non-structural pieces such
as modifying land-use regulations within areas deemed atrisk. “Springbank makes a significant improvement for many
communities and hundreds of thousands of Calgarians,” Frigo
says. “But there will always be a residual risk that needs to
be managed through emergency response, forecasting, land
use regulation, insurance, and other structural measures, and
things like flood barriers, pump stations, and drainage system
improvements.”
So, even when flooding does occur — and Frigo has little
doubt it will — there’s reduced risk of widespread evacuations,
service disruptions and extreme damage. “This investment
is coming to fruition at a time where Calgary has seen really
significant growth and intensification,” Frigo says. “Commercial,
residential, recreational spaces, even our environmental and
open space areas, are all valued that much higher because of the
degree of growth that we’ve seen regionally and within the city.
So, Springbank could never be more welcome as an important
component in singlehandedly reducing the flood exposure of
the City of Calgary by tens of millions of dollars per year which,
over the 110-year lifespan of the project, accrues to billions of
dollars of benefit.”
Water Canada requested an interview with Alberta
Transportation and Economic Corridors, but no one was
available to answer questions.
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