YELLOWKNIFE, N.W.T. – In the nether world of ice road trucking there are many contradictions and events that cannot be explained by the evidence of the senses: cracks in the road wide enough to swallow a hand are commonplace and not considered dangerous, for example.

Then again, the road can open up under the weight of the first truck in a convoy, allowing it to pass only to swallow the second or third. Pressure ridges can form instantly, buckling the ice into impassable vertical walls. Waves caused by coming off a portage too fast can carry the length of a lake, blowing out the ice at the next land crossing. A crack can turn from dry to wet, becoming dangerous as it deepens to allow lake water through the three or four foot ice road bed onto the surface of the road.

A warm day can make the ice “slippery.” The ice – and more specifically the road – is constantly changing. Temperature variations, traffic, snow cover, any number of circumstances, can make the road hazardous, even impassable.

On a good day, however, it hardens and more traffic and heavier loads can move.

There is no better evidence of this than on the Lupin Winter Road in the Northwest Territories. The Lupin Road stretches 643.6 km from Yellowknife to the Lupin Mine, just below the Arctic Circle.

The vast majority of the route is over water, large lakes requiring two or three hours to cross and smaller bodies needing only a few minutes.

But make no mistake, the entire road is ice – even the portages are cleared land that’s flooded.

Once a base layer has frozen, the process is repeated – think of the backyard rinks we all enjoyed as kids. Another layer is frozen on top again and again until the ice is about six inches thick.

These portages are impassable without ice as the muskeg and earth would become a quagmire after the first crossing were it not for protective layers.

When the thaw begins in March, it is the condition of the portages that signal the beginning of the road’s final days. Weight restrictions and traffic volume are lowered, but when the portages can no longer be iced, the road is done.

The Lupin road actually begins 43 miles outside of Yellowknife, at the end of a paved road known as the Ingraham Trail.

For Ben Rausch, a driver for Robinson Truck Lines, the road is the worst part of his journey north. It is a narrow, twisting road with steep ditches immediately abutting the pavement’s edge. The speed limit is 70 km/h, but there are many limited sight distances on hills and curves that hide slow moving four wheelers and Japanese tourist buses – always stopped trying to catch a glimpse of the Northern Lights.

Ben is happy to stop at the first portage onto Tibbitt Lake and crawl out onto the ice. He moves slowly down the slight grade to avoid launching a pressure wave beneath the ice and begins the gradual crawl northward to the first camp, Lockhart, 195 km north.

It will take him 10 hours of non-stop driving to reach the camp. He keeps a steady pace in order to maintain his place in the convoy. Truck sequence must remain constant from dispatch until checking in at a camp. The road is patrolled by private security people who have the power to suspend a driver from operation. They monitor speed, spacing, portages and general safety.

Drivers use VHF radios tuned to LAD ONE to announce they are approaching a portage. Northbound trucks always have the right of way and those heading south must wait until the portage is clear before starting in.

Drivers can even be disciplined for ratchet jawing on this channel since it is absolutely essential to communicate portage crossings without interference.

It requires discipline to work this road for the two- or three-month season but drivers are well rewarded. Many return year after year for the pay and the adventure.

Despite the obvious dangers, the slow speeds, constant white landscape and numbing cold, can make a driver believe his shift will never end. The camps are welcome relief from the monotony.

The food is well prepared, plentiful and free. At Lockhart the single telephone is always busy with drivers calling home to Newfoundland, P.E.I. or Saskatchewan, distant places made even more remote by the unforgiving sub-arctic just outside.

Perhaps the volume of freight this year, nearly 8,000 loads for Robinson Trucking alone, bespeaks the changes in store for the Northwest and the road itself. There is talk of the N.W.T. taking over the road. But perhaps the most ominous change is the impact of global warming.

Five years ago, the road opened in mid-January, according to Clinton Westgard, an owner/operator with Land Trans. There is no telling when the road will disappear this year but the seasons have been getting shorter at both ends, he insists.

According to Marvin Robinson, president of Robinson Truck lines, the typical season has been running about 62 days in recent years. He notes, “the ice has not been very good the past couple of years.”

This year the road opened Feb. 6, and 10 days later, trucks weighing 85 per cent of capacity were running north. How long the ice will bear full capacity loads, weighing as much as 56,800 kg, is anybody’s guess.

There is obviously a certain amount of guesswork involved in ice road construction and maintenance. Ice is a constantly changing substance and the evidence of the senses says very little about its ability to remain stable as loads move across it. It is always expanding and contracting even as long lines of iron pass over its surface.

For this reason, the ice is tested throughout the season, though holes drilled and subsurface interface radar scans from helicopter are used more frequently at the beginning and end of the season to ensure the reliability and weight bearing capacity of the road. Lightly loaded trucks are permitted at the beginning of the season to help develop the ice. As the ice reaches its full weight bearing capacity, heavier loads are permitted. Then, as the season nears its end, daytime traffic is curtailed in favor of night running when colder temperatures prevail. Indeed, many heavier loads and oversize freight move at night throughout the season.

Given these changing conditions, it is necessary to verify the frozen water’s ability to become and remain a highway. No one can look at the ice, or listen to it, or feel it, and say with certainty that it is safe.

Those who know the road say white ice is not as safe as blue. But the ability to survive by reading the frozen world’s fast changing conditions is a lost art. Nowadays, augers and radar do the soothsaying and a formula says when the ice has the maturity to allow safe passage.

P = 4h-squared, defines the thickness necessary; where P is allowable weight and h is thickness of ice. On a roadbed 121.92 cm, 59,458kg are allowed to pass.

Despite formulas and testing, the ice is often difficult to read. It may be quite thick enough at one test site and 30cm thick a few metres away.

Air bubbles may form. Sometimes the snow thrown to the roadside by plows can force the roadbed up into a crown high enough to create “live” or wet cracks. The snow banks themselves may harbor cracks invisible to maintenance workers or trucks straying off the road under whiteout conditions.

It is thought that the only death on the road in well over 12 years was caused by such a crack. Last December, a Snow Cat operator went through the ice in his 5000-lb vehicle. While most survive this ordeal – providing they get out of the vehicle before getting wet – the Cat operator was drenched instantly and did not survive.

Nothing is what it seems in the world of the ice road. The adrenaline of both fear and adventure is generally washed away by the bland water of boredom. But then the road suddenly opens up without warning and…

…Such is life for the men and women who leave the concrete highways to test themselves and fatten their paychecks on the Lupin Winter Road. n