Q&A: Why did the Inuvik-Tuk highway close, and what’s next?
Officials overseeing the Inuvik-Tuk highway say the road is missing around $700,000 in gravel.
The contractor responsible for building the highway is rushing to add the remaining gravel over the next few weeks, which will help to cure four areas of the road that remain soft.
That gravel couldn’t be added in time last year, before the road opened, because work overran and freezing conditions set in.
The highway closed for much of May because areas became impassable as temperatures increased.
Kevin McLeod, assistant deputy minister at the Department of Infrastructure, says the closure can be blamed on a wetter-than-usual spring combined with people ignoring barriers, creating huge ruts in the road surface.
Here’s a full guide to what’s happening at the highway, as provided by territorial officials at a briefing on Wednesday.
Quotes from Kevin McLeod, Department of Infrastructure
Last year: building the road
McLeod gave an introductory overview of factors involved in building the Inuvik-Tuk highway, which cost $299 million – $200 million was provided by the federal government, and $99 million by the territorial government.
“Designers and permafrost engineers from around the world looked at this very carefully. We had all kinds of experts involved in the risks, the design, and what we had to do. Two northern contractors, one in Inuvik and one in Tuk, joined forced legally. All stakeholders met twice a year. Rumours were squashed, initiatives were picked up.
“Anything done in Canada is highly regulated. They all had full-time folks assigned to the project to be their eyes and ears on it and we worked well with those regulators.
“We built it around climate change and long-term predictions. There are over a hundred sensors in the road bed with more to come, and we’ve got some test sections in the road bed to deal with new ideas when it comes to permafrost.
Deciding to open the road
In November 2017, the territorial government decided the highway was sufficiently ready to be opened to the public, even though work had overrun and much gravel remained to be laid. Kevin McLeod discussed that decision, comparing it to a kitchen that is “generally good to go … except the hot water tap doesn’t work and there are some paint chips.”
“There might be some deficiencies and unfinished work, but the department feels that public traffic can go on the road and the engineer signed off. You go around with an independent engineer, you agree to what’s unfinished and what has been done but needs correction.
“On November 15 there was a deficiency list and there were some unfinished works – the contractor needed to do some surfacing gravel compaction in km 21-45 and km 122.8-138.9. But the road was frozen, it was hard, and it was much safer than building an ice road. Our confidence level was extremely high.
“The decision to open it, I think, was based on the engineering and the fact that it was done. If we didn’t open it, the ice road would have had to be opened up for $400,000 or $500,000, lots of effort, and folks would say that’s going to take another eight or nine weeks to get that going.
“It would have closed again at the end of March or beginning of April. People would say, ‘Well, why aren’t you opening up that road?’
“Generally [throughout the first six months] the road remained open. It was closed a couple of times due to blizzards but so was Highway 8 at the same time, for safety reasons.”
Closing the road in May 2018
The highway was closed intermittently in the spring, then faced a full closure for several weeks from May 12. McLeod discussed the decision to close the highway and the factors behind that, including people driving around barriers and leaving deep ruts in the surface. “In 40 years of delivering major projects, people continue to surprise me,” he added, ruefully.
“We identified three risk times: in the spring when the sun came up and heated the surface; freshet combined with the rain in late May or early June; and the late August timeframe when it is the warmest, because the sun has been absorbed and the permafrost is at its warmest.
“We started restricting traffic in the April 27 timeframe. That was the first time the sun was beating down on some areas that became soft. We used a method of travelling in the cooler parts of the day, with no traffic noon-midnight, which worked out really well until we had some folks not respect that who produced some deep ruts.
“The gravel surfacing on this particular area was only a couple of inches thick. Once that was broken through, you’re getting into a very soft, muddy area. We did see folks who drove around the barriers and got through, but they were likely up to their axles and they broke through the crust. Once that happens, the road is unrecoverable in terms of trying to drive on it without a lot of effort. We had to close the road.
“We said there was still going to be some work on it in the 2018 season. Those are all points we made to the public. But the fact we closed the road wasn’t a scenario [that had been expected].
“The road was closed on May 12 as those ruts got worse and filled with water. We opened the road again to light traffic on June 1.”
The work happening now
McLeod explained that the remaining work to finish the road is covered by $1 million the territory is holding back from the contractor, adding it will not cost the territorial government any additional cash. He also outlined what that work will entail.
“There are four sections that are soft and that it is critical to us to repair. They are working on it. One to three weeks is my guess in terms of how long it’s going to take to cultivate that area, to dry it out and put the gravel to the point where it can be compacted.
“We are continuing to repair soft sections and the contractor is working about 14 hours a day now, grading, dumping gravel, compacting, and re-grading again. We want to lift the restrictions as soon as we possibly can.
“If folks have a special need or some essential traffic that must go through, we have already done that twice. It is possible to go through under certain conditions.
“We have given the contractor till October 31 to get everything done that they need to get done. If they don’t, then it’s a discussion with the contractor. The contract has lots of clauses in it about what happens when things don’t get done. The owner has to make some decisions on invoking those contract clauses, and it would all depend on what is left undone.”
The road’s gravel surface
McLeod went into more detail about the work remaining to ensure the appropriate depth of gravel surface is in place across the entire highway.
“The sub-base, and base, of a road could be 14 ft or 15 ft thick in terms of the engineering of it, to make up the road and take the weight of the traffic that’s on it. The gravel surface should be thick enough that it distributes the weight properly. In some areas that could be 150mm, in others it could be 300mm.
“In the soft areas, the gravel surface is 50mm – which is a third of ideal.
“Our contract says the whole road will have 150mm of crushed and processed gravel. There was enough gravel in the area, it just wasn’t in the right spot because they ran out of time.
“But there’s more to it than just laying gravel. You have density tests where a technician walks the whole road and it has to meet our specifications. It needs to be compacted, watered, compacted again.
“It may take 36 hours to do a kilometre, and it involves about nine passes of the roller over a certain area.”
Why wasn’t this work completed last year?
McLeod explained that as the weather got colder, gravel at gravel pits – waiting to be laid onto the road surface – froze up, making it impossible to move or spread.
“The contractor was behind schedule. Freezing generally followed the normal course. It’s a long project. They just ran out of time.
“The project wasn’t significantly adrift at all. The road started freezing at the end of September so we knew that, at night time, the road bed was freezing and the gravel source was starting to freeze up. We had two months of [telling the contractor]: ‘You’re not going to get this done and here’s how to mitigate it.’
“We have an ideal construction window. If you miss that, you have to wait until it comes around again. If they had five more weeks of perfect weather [in fall 2017] they would have finished the road.”
Lessons learned
McLeod said he expects the highway to be “the most researched highway in the world, potentially,” given the level of scientific interest in its development. He also said the territory’s $1.7 million annual operations and maintenance budget for the highway “feels right” at this moment in time. McLeod ran through lessons the territory has learned so far.
“This was a new road in a new area that we had never been in before. We did see some snow accumulate in certain areas due to the topography and had 9 ft or 11 ft snowbanks, which are quite high. We need to manage that differently next year with some snow fences or other mechanical means to reduce snow on the side of the road.
“This year saw significantly more rain in the area, three times as much as we expected. That was beyond our planning. We are looking at additives in the gravel to assist with dust and water.
“All the other sections are performing completely as designed.
“In the springtime, North America does have a system of road bans to reduce weight so they don’t damage the chipseal or pavement. We do it on all our other highways, there’s no reason to think that we wouldn’t do it on this one – but it won’t be to the point where it’s closing. That is not where we want to go.”