Iqaluit
International
Airport
Thermosyphon system creates a barrier between a building’s
heat and permafrost, like “a big mattress floating on ice”
About 7,000 people live in Iqaluit and fewer than
36,000 in Nunavut, one of the world’s most remote
and sparsely settled regions. With more than
two million square kilometres of land and water
spread across three time zones, Nunavut is the largest of
Canada’s provinces and territories. No roads connect any
two of Nunavut’s municipalities or hamlets, and sea access
is limited to a small number of sailings between July and
October. Therefore, the Iqaluit International Airport is the
south’s gateway to Nunavut in the eastern Arctic, where
access by air is essential for necessities like fresh food and
emergency medical treatment. More than 1,500 medevac
flights leave for southern cities annually, and every year 10
to 20 wide-body intercontinental airplanes land in Iqaluit
for mechanical or medical emergencies, or to refuel.
Philippe Gesret was the project director for Bouygues
Building Canada Inc., which along with Stantec – the
Edmonton-based company provided full architectural,
engineering and interior design services – was part of the
Arctic Infrastructure Limited Partnership consortium
that built the new airport in partnership with the
Government of Nunavut. This was the first public-private
PROJECT SPOTLIGHT
design-build-finance-operate-maintain project of its kind
in North America. “It was a wonderful project – an amazing
project,” said Gesret, but one that came with more than a few
unique challenges.
Two new buildings – the air terminal building, about
10,000 square metres, and the central services building,
just under 5,000 square metres – as well as additions and
upgrades to facilities and runways, had to be constructed
while the existing airport remained fully operational. These
structures were built on permafrost, which consists of rock,
gravel, sand and organic matter bound together by ice.
Permafrost thawing, instability expected
to increase
Permafrost is found throughout Nunavut and is especially
common in wet or coastal areas, river valleys and low-lying
peaty ground. It can be as hard as rock when frozen, says
Gesret, but in Iqaluit, a metre of the surface now thaws for
about six weeks per year, and that depth – and the period of
thawing – are both expected to increase with global warming.
The natural seasonal thawing and freezing of the surface layer
commonly causes heaving and settling of slab-on-grade
By Barb Feldman
PHOTO: CÉLINE CLANET
PILING CANADA 49