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'Living, moving, breathing' road to the Beaufort Sea will be under the microscope

'Living, moving, breathing' road to the Beaufort Sea will be under the microscope
From CBC - November 14, 2017

Building the road was only half the battle.

Keeping it in one piece with the freeze and thaw of its underlying permafrost, and in the face of the threat of global warming, will be a monumental task as well.

The Inuvik to Tuktoyaktuk highway will open this week. At 137 kilometres, it's not the longest unpaved road in the North, but with a price tag of just under $300 million, it may be one of the most expensive on a per kilometre basis.

It's also unique among road-building projects, explained Merven Gruben, vice-president of E. Gruben's Transport Ltd., one of the companies involved in building the road.

Construction was limited to winter months so tundra and underlying permafrost would not be damaged. But winter in the North has been getting shorter, or at least felt that wayduring the past four years of construction.

"Our biggest obstacle was the season was getting shorter,"Gruben said.

The highway cost $2.2 million per kilometreto build, and will cost another $12,000 to $15,000 per kilometre every year to maintain. That means at least $1.5 million in annual maintenance costs, or about $1 million more every year than it cost to build the annual winter ice road between the two communities.

'Living, moving, breathing' road

The high costs of building the road and maintaining it are not only because of the premium paid for any construction project in Northern Canada, but because the road is built on what is essentially a living terrain of streams, tundra and rock.

"It's a living, moving, breathing form of infrastructure," said Kevin McLeod, the assistant deputy minister of asset management for the Northwest Territories government.

"We are in a very complex environment in the North. It's a project that has never been undertaken anywhere else in the world."

Rick Hoos can attest to that. He's the principal consultant for Kiggiak EBA Consulting Ltd., a company involved in the environmental assessment, permitting andconstruction of the highway.

"It's located on permafrost," he said. "The top twometres of the terrain thaws in the summertime. One of the ways of dealing with that is to build a bermwhich is the roaddeep enough so that the ground below will remain frozen. The road itself acts as an insulator."

"The key to it is to have the road base deep enough so that the ground underneath the road base will not thaw in the summer time and that's the primary principle on which the road was built."

Researchers are monitoring the underlying cogency of that primary principle.

"I am involved in research to find possible solutions for expected deformations," said Marolo Alfaro, a professor of geotechnical engineering at the University of Manitoba.

His project is funded by the government of the Northwest Territories. Alfaro and his team are more than two years into a six-year study. They have been monitoring certain sections of the highway with sensors to get a better understanding of the stability of the embankments the road lays on.

The road was built with this kind of study in mind. Test sections were included during construction to gauge the effectiveness of different road reinforcement methods.

Alfaro said that after this spring thaw they recorded some movement but nothing catastrophic.

Heavy use intended

Not the only road built on permafrost

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