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Researcher urges using piles to make Nunavik homes more stable

Housing development in Nunavik faces two challenges: thawing permafrost and a lack of gravel.

According to Laval University geography professor Michel Allard, a more sustainable way to move forward would be to use piles — steel or wooden beams driven into the ground to support a building’s foundation — rather than building on gravel beds.

He presented results of his research to Kativik Regional Government council at its meeting Tuesday.

With a team of graduate students at the university’s Northern Studies Centre, Allard analyzed how recently constructed buildings in Nunavik were already being damaged by thawing permafrost.

In Inukjuak, for example, they found crooked foundations in houses that were built between 2000 and 2010.

“Communities have been spreading over sensitive permafrost,” Allard said, and the thaw has caused the ground to shift and displace the foundations.

“Housing construction is made on flatlands in communities” where water tends to accumulate naturally, he said.

In most cases, the ground consists of ice and clay which is prone to deformation.

“The idea is to have foundation for the buildings that will last in adaptation to this risk created by climate change,” Allard said.

Meanwhile, with a shortage of gravel it is becoming increasingly difficult to find the resources needed to build the kind of foundations usually used in Nunavik.

According to KRG, the villages of Quaqtaq, Kangiqsujuaq, Salluit, Ivujivik, Puvirnituq, Umiujaq and Kuujjuaraapik all face a shortage of gravel or only have a distant and costly access to it.

Allard said that in many communities a single gravel pad for a home can cost more than $250,000.

He said there has been an overexploitation of gravel. Speaking to council, he showed two instances in Puvirnituq where a gravel pad was built on top of bedrock.

“The bedrock underneath is solid enough,” he said.

If done correctly, he said, building on bedrock would be as solid as building on a gravel pad.

Allard said he asked numerous homebuilders that build housing for Nunavimmiut or for staff what their estimated construction expenditures would be for the next decade. The total added up to more than $6.5 billion.

“Most constructors agree that gravel pads are not the adequate foundation anymore,” he said.

In addition to its high cost and the lack of available gravel, pads deform, there are compaction problems and they impact natural water drainage systems.

As an alternative, Allard suggested each community should have a drill and a crusher.

With these tools, he said, piles could be drilled into bedrock to provide stable foundations. That work could be done between April and June, providing a head start to the construction season.

By using bedrock as a primary foundation and gravel to put in place additional support only, the use of granular resources would be reduced by 53 per cent, Allard said.

The foundations would also be more stable and would stand up to thawing permafrost.

“The recommendation in our report is for the government to support the purchase of drills in the communities,” he said.

Allard said Nunavik organizations could purchase 14 drills for all the villages at a cost of about $710,000 per drill.

Cedric Gallant, Local Journalism Initiative Reporter, Nunatsiaq News