Unauthorized driving, wetter-than-normal spring behind Inuvik-Tuktoyaktuk Highway closures

This spring's closures on the Inuvik-Tuktoyaktuk Highway are a result of unusually wet weather and drivers failing to respect road closures, according to engineers with the Northwest Territories Infrastructure Department.

Canada's newest Arctic highway faced intermittent closures this spring including for most of May due to muddy, slippery conditions. On Wednesday, the government held a briefing on the closures to explain why they happened.

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The region saw about 23 millimetres of rain in April about three times what engineers had expected, said Kevin McLeod, an assistant deputy minister with the Infrastructure Department.

That rain combined with the melting snow to create muddy conditions during the day, even though the top layer of the road froze again at night, he said.

Soft road, deep ruts

In response, the Infrastructure Department instituted half-day closures for two weeks. Drivers who did not respect those closures caused deep ruts, which made the road impassable to traffic, McLeod said.

"We did see folks who went around the barriers and drove on it when it was very soft," McLeod said. "Trucks could go through, but they were in up to their axles and they broke through the crust. Once that happens, the road is unrecoverable in terms of driving through without much effort."

When the road was open to traffic, it worked as designed, he said.

"When it was open and they were managing the traffic and folks were driving when the conditions were appropriate, it was functioning," McLeod said.

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The road opened with community ceremonies in Inuvik and Tuktoyaktuk last November. At the time, officials warned that the road still needed to be finished, but said it was "substantially complete."

But there were sections between kilometres 21 and 45 and kilometres 122 and 139, that weren't complete by that opening date. Gravel still needs to be put down and compacted at those areas later this summer, along with some final work with bridges and signs.

Engineer signed off on road opening

"Substantially complete" is a defined term the government had in its contract with the road's builders. It means the road is safe for public traffic and an independent engineer signed off on the decision to open the road, McLeod said.

"On Nov. 15 the road was frozen, it was hard, it was much safer than building an ice road. Our confidence level was extremely high," he said. "An independent engineer who's looking at it purely from a public safety point of view and [contractual] point of view said: 'You can open it.'"

The Inuvik-Tuktoyaktuk Highway reopened to light traffic Tuesday to protect the road from further damage. On Wednesday, the weight restriction was set at 64,000 kilograms.

The weight restriction will likely be in place until the end of June, though the government will allow some essential heavy loads through on a case-by-case basis.