Contractors in Manitoba have developed unique methods for constructing and maintaining a winter road system.
Roadbuilding
Contractors in Manitoba have developed unique methods for constructing and maintaining a winter road system.
Typically, road construction begins to slow down during the winter and pick back up again in the summer.
However, the opposite is true for Manitoba’s winter road network, which is constructed in cold weather.
“There is quite a bit to building winter roads,” explained Ken Erickson of Sigfusson Northern, a Winnipeg-based heavy civil construction company.
“It’s not like the old days when the loads were lighter and delivered by cat train. Today, it’s a very methodical and unique procedure that we follow. Roads are inspected on a daily basis to insure safer travel. It’s never 100 per cent safe, when dealing with ice.”
A $9 million investment by the federal and provincial governments opened up the 2,200-kilometre winter road system to commercial trucks and other vehicles in early February.
The roadways allow access northern and remote communities.
The work was performed by 23 companies, including Sigfusson Northern, and created work for about 100 employees.
Construction and maintenance work is contracted out, primarily to local communities or First Nation joint-venture companies, which also creates local construction training opportunities.
With the first snow of winter, companies use lightweight equipment, such as snowmobiles, to pack the snow on both land and ice.
“The key is to get out there and get the roads packed each year and try to do improvements, such as smoothing the roads out,” said Erickson.
“We get the snow packed before the heavy frost. Once packed, the air comes out of the snow, so the frost will go down deeper into the ground and freezes the swamps. We also remove the snow off the ice so the frost will go down and build the ice faster.”
As the ground hardens, heavy graders and snowplows are used to scrape away excess snow, as well as keep the roadway covered with enough snow to remain reflective.
This work ensures that heat from the sun is not absorbed and the road remains frozen.
The system takes the path of least resistance, by following natural terrain features such as muskeg, lakes, rivers and creeks.
“With most of the winter roads we route the roads away from ice crossings and try to stay on swamps and land as much as possible,” he said.
When the ice can support snow removal equipment, the path is plowed clear, so the ice can form naturally.
On short ice crossings, such as across a river, the ice is cleared and flooded one or more times until it reaches the required thickness.
For long ice crossings, such as a lake, tree markers are placed to define the route, which is typically about 60 metres wide.
“River crossings usually require flooding, to meet the road standard load bearing capacity,” explained Erickson.
“Blue ice is the strongest ice, but beware of the cracks, especially running parallel to the ice road.
There will always be cracks because the ice has to give when it has weight on it.”
Ice crossings must be able to support loads of up to 36,500 kilograms, providing the speed of vehicles is kept to a maximum of 15 kilometres per hour and vehicles are spaced at least one kilometre apart.
The winter road system not only facilitates the movement of freight to northern and remote communities, but also provides the residents with temporary inter-community travel and access to the rest of the province.
Each year, about 2,500 shipments of staple items are moved to these areas by commercial trucks.
Northern communities are served by these roads during a brief period of about eight weeks from mid-January to early March.
However, the prevailing weather conditions can shorten or extend this period by as much as two weeks.
This year, the road system opened about one week ahead of last year.
Recent Comments
comments for this post are closed